1942: Chemistry

The war has, of course, been the dominating influence throughout 1942 in chemistry as in practically all activities. The requirements of the military establishment and lend-lease have brought profound changes and stimulated many important developments, but in many cases information concerning them cannot be published during the emergency. To a great extent the story of 1942 is concerned with the rapid development and utilization of products and processes.

The chemical industry has turned more and more to production for war needs, and this has necessitated great expansion of many units, as well as considerable readjustment. Concurrently a number of related industries have been converted from their normal activities to work that at first glance would seem not even related to their peacetime interests. Several of the large chemical companies have contracted with the Government for the erection and management of war plants, owned by the Government, where their skilled direction and personnel are proving invaluable.

The personnel problem arose early in the year and confronts the chemical industries even more than the colleges and universities. Trained and experienced chemists and chemical engineers are needed in war work in ever-increasing numbers, and when new plants now under construction come into operation, the need will be even more acute. To improve this situation some colleges and technical schools are speeding up their instruction, adding evening courses, even encouraging the enrollment of women.

One of the great differences between this war and World War I is where scarcities have appeared. Twenty-five years ago we lacked potash, nitrogen, dyes — all now available here in sufficient quantities. On the other hand, unexpected scarcities keep cropping up, often in places where only a few months ago there were surpluses, as in metals, rubber, plastics, silk.

The Alien Property Custodian in December announced that he had taken over some 50,000 enemy-owned patents, many of them covering such important chemicals as dyes, drugs, alloy steels, aluminum, and magnesium. These are to be licensed to United States manufacturers, and already a considerable number of applications have been received.

Early in 1942 many difficult problems were suddenly put to the chemists and chemical engineers of the country; the Japanese overrunning of the Far East removed our source of supply of essential strategic raw materials.

Rubber.

The rubber situation has undoubtedly been foremost in the public eye of late. Although during the past few years several types of synthetic rubber had been brought into commercial production on a small scale in the United States for specialty uses, they had had to compete with cheaper natural rubber. Our stockpile of natural rubber had been built up to a size the largest in our history, yet still far below the needs that developed.

Last spring and summer rubber chemists worked night and day, while over their heads raged the controversy of whether to use alcohol or petroleum for making butadiene, and which process should have precedence in making other types of synthetic rubber. The report of the Baruch Committee and the appointment of W. M. Jeffers as Rubber Administrator brought order out of what had approached chaos. As The New York Times said editorially, 'Unquestionably the very best formula for synthetic rubber is the one President Roosevelt has hit upon. It comprises Baruch, Compton, and Conant. The finest ingredient for producing any mixture is brains.'

The problem of supplying needed rubber was thrown squarely into the laps of the technical men, to be solved only by the production of 'synthetic rubber' in quantities heretofore hardly imagined. Our goal is now 877,000 tons annually, and if the program can be carried out it is expected that in September 1943 synthetic rubber will be manufactured in large enough amounts to offset the drain on the natural rubber stockpile.

In May two of the Government's new plants erected for synthetic rubber went into production. The making of butadiene, to be polymerized into rubber, from alcohol and from petroleum has gone forward faster than at one time seemed possible, but late in December it was reported that the program was lagging. Delays in finishing synthetic rubber plants are traceable to the demand for new aviation gasoline refineries, that require the same sort of equipment as the butadiene plants. There are bottlenecks in such equipment as heat exchangers, boilers, turbines, and electrical equipment, which must compete with army and navy demands.

In spite of the rush to get into production the types of synthetic rubber that we know how to make, research has gone forward in other directions, and Flexon, similar to butyl rubber, and Noropol, made from soybean and corn oils, are now being tested on a pilot-plant scale; and a rubberlike substance made from dairy by-products has been announced. The Houdry process for catalytic cracking to produce butadiene commercially from oil was announced in July, and a catalytic process of oil refining known as isoversion is expected materially to increase production of 100-octane gasoline and synthetic rubber.

A great deal of attention has been devoted to producing substitutes for rubber. At least three types of resins familiar as the interlayer in safety glass have been used in waterproofing fabrics. Formulations of ethylcellulose plastics have been developed to replace rubber in electrical tape, insulation, and coated fabrics. An elastic yarn from vinylite resins is said to be superior to rubber for military equipment because of resistance to sunlight, tropical heat, and humidity. Resistoflex, a rubber substitute compounded from polyvinyl alcohol, is used in gas and air lines on automatic machines for forming radio tubes, for tubing and hose, washers, and mechanical parts. Transflex tubing, used to secure continued effective insulation on aircraft flying at high altitudes, is transparent, flexible, and resistant to brittleness down to —50° C. Synthetic rubber thread has been made from Ameripol and put into parachutes, gas masks, respirators, etc.

The United States Department of Agriculture reported an economical process for making butylene glycol from farm crops, and has developed it to a pilot-plant scale. Useful as an antifreeze and in commercial solvents, it is also being studied as a possible link in the production of butadiene.

Auto tires made of 99.84 per cent synthetic rubber are now being tested on the highways of the country. Several plans have been advanced looking to the use of reclaimed rubber and also of such synthetics as Thiokol for tires for civilian use.

A new method of reclaiming used rubber, which is said to increase the capacity of certain existing equipment by 60 per cent, has been developed by the U. S. Rubber Co. The processing cycle is reduced from 16 to 9.5 hrs. and the quality of the finished reclaim is improved.

A mission has been sent to Russia to study synthetic rubber methods there.

Concurrently, investigations of guayule, the Russian dandelion, and other possible rubber-bearing plants have taken on new urgency and plantings have been made on a large scale. Efforts are being made, with gratifying success in spite of small tonnages, to secure as much natural rubber as possible from South and Central America, and recently an abandoned rubber plantation in Hawaii was reported as about to be tapped after years of neglect.

Medicinals and Pharmaceuticals.

Quinine was obtained largely from Java until the Japanese blitz, and its scarcity is especially serious when our armed forces are fighting in the malarial swamps and jungles of the Far East. Efforts are being made to get natural quinine from South and Central America, and three substitutes have been developed — totaquine, atabrine, and pamaquine naphthoate. Atabrine is now being produced in this country at the rate of half a billion tablets a year and promises to give excellent service.

Work has continued on the sulfa drugs, which worked almost a miracle after Pearl Harbor, bringing about absence of pus in wounds, mildness of postoperative reactions, and swift clean healing of wounds, even when contaminated with soil. Not a single massive infection was found ten days later, whereas in World War I infection killed 80 per cent of men with abdominal wounds. After Pearl Harbor not a single loss of arm or leg was necessary because of infection. These drugs have also been found helpful for such diverse ailments as the common cold, peritonitis, impetigo, subacute bacterial endocarditis, and skin infections.

Sulfanilylaminoguanidine, similar to sulfaguanidine, has been prepared and found useful in treating bacillary dysentery. A British scientist showed that sulfanilamide attacks bacteria by starving them. It resembles p-aminobenzoic acid, which some bacteria need for growth, but does not promote growth.

A new surgical dressing that is useful for burns and wounds has been made from a sulfa drug film that can be cut and rolled like a bandage.

Antibodies were formed artificially in the laboratory for the first time, by modification in shape and structure of large molecules of certain blood proteins, serum globulins, which takes place in the presence of disease germs or virus particles.

Experiments at Johns Hopkins hinted at the existence of a paternity chemical. Ability to become fathers was lost by human volunteers who lived on a diet lacking in arginine, one of the ten essential amino acids.

Curare, the deadliest of all poisons, was isolated in pure crystalline form, four times as powerful as curare extract.

Fluorescein injected into a vein is used to show under ultraviolet light how fast blood is flowing through the body and whether amputation is required.

Clotting globulin, the natural clotting constituent of blood, is separated in highly concentrated form from clear blood plasma and offers new hope for hemophiliacs and help in surgical treatments to prevent excessive bleeding.

Vitamins.

Discovery of the structure of biotin was announced by Vincent du Vigneaud and is expected to pave the way to the synthesis of this supervitamin. The empirical formula was established about two years ago.

Vitamin E is now being produced, starting with soybean, cottonseed, and corn oil. Recent advances include the production of pure crystalline vitamin A and its esters, crystalline alpha-tocopherol acetate, and gamma-tocopherol palmitate, and isolation of the new provitamin A, which has been named kitol and isolated from whale liver oil.

Riboflavin, vitamin B₂, was to be required in enriched flour beginning July 1, 1942, but the date had to be postponed to April 20, 1943, because sufficient vitamin was not available for the purpose. Concentrated riboflavin has been made from whey.

Persimmon leaves were found to be rich in vitamin C. This vitamin was reported helpful in hay fever and in staving off heat prostration. It seems to be drained from the body in perspiration, like salt, and can be supplied in tablets in a similar way. Color blindness was helped by vitamin A treatment. Germs that destroy pantothenic acid were suggested as being at the root of the gray hair problem. Synthetic vitamin K was suggested as a preventive of tooth decay.

Substitutes and Alternates.

A number of substitutes for rubber have already been mentioned. Many metals and structural materials have also become scarce, and the plastics that were first considered as replacements are feeling the pinch in their turn, as raw materials become unavailable while the demand continues to mount.

At the Second National Exposition of Chemical Industries, held in Chicago the last week of November, the exhibit of the American Chemical Society was devoted to 'Substitutes and Alternates,' many of them products of the other exhibitors.

Tin is one of the critical materials, especially now when canned foods are needed in ever larger quantities for the fighting forces and for Lend-Lease. Quick-freezing and dehydration are helping and new types of containers are being developed. A fiber container that can be made on the same machines used for fabricating metal containers promises to be excellent for dry products, drugs, spices, etc. Lead tubes for tooth paste have wax or resinous coatings to protect the contents. A lacquer substitute for tin coatings, made from lactic acid and vegetable oils, can be used with evaporated and condensed milk and cheese.

Half of the tin in a can can be saved by a new electroplating process, using a neutral instead of alkaline solution, which gives a thinner and more uniform coating. Lead bearings can be used in place of tin, and alloys with lead as base metal in Diesel engines and air compressors.

The electrolytic tin-plating industry is being expanded to take care of a large portion of United Nations' tinplate needs. A year ago there were only two continuous tin-plating lines capable of handling strip 30 in. wide at speeds above 300 ft. per minute. Now 14 new lines are in operation.

A new process for recovering tin from tin cans has been put into commercial operation after being tested for five years. Methods have been worked out for recovering about 24 lbs. of tin oxide and almost a ton of scrap steel from a ton of discarded cans.

Silver can replace tin in soft solders and in brazing alloys, and can be used in bearings for aircraft engines. Silver-lined containers are being considered for foodstuffs, chemicals, etc., as investigation indicates that pore-free deposits of silver 0.001 in. deep on deep drawing steel are readily obtainable, and on suitable base metals deposits as thin as 0.0001 in. are possible. It seems practicable to manufacture relatively low-cost silver-lined containers, such as barrels, drums, and the like. Silver can replace copper in bus bars, windings for transformers, and similar electrical apparatus. However, although there is a large stock of silver in the country, most of it is held by the Treasury and under existing laws can be released only in comparatively small quantities and for uses where the silver can be returned after the war.

Saran is a chemically resistant thermoplastic resin that as pipe and tubing offers almost unlimited possibilities in chemical processing plants. It is tough, durable, flexible, lightweight, and resistant to abrasion and corrosion.

Lead pipe and tank linings are replacing rubber in industrial operations. Lead gaskets and collapsible tubes are saving tin and aluminum. Leadfoil laminated wrappings are being widely used, and lead coatings save zinc, tin, cadmium, and nickel formerly used to protect iron and steel. Lead alloy couplings are used for copper and bronze on certain types of cement-asbestos pipe.

Zirconium oxide is replacing tin and antimony oxides in the ceramic industry, and zirconium and titanium products take the place of mica and steatite in the electrical field. Lignin and lignin plastics are used in place of phenolic plastics or metal. Paper tubes are now manufactured to precision tolerances on specially adapted heat die machines, and automatically wound spirally. Palladium alloys have been developed to save platinum, no longer allowed in jewelry.

Fused glass drops, just as good as formerly imported sapphire jewel bearings for electrical indicating instruments, are now being produced in quantity in this country. A radio panel can be made from a layer of spun-glass cloth sandwiched between fireproof plastic.

Thousands of hoarded pennies and nickels were turned in as the result of a recent drive instigated by the shortage of copper and nickel. A nickel-less 5-cent piece containing 56 per cent copper, 35 per cent silver, and 9 per cent manganese instead of the 75 per cent copper and 25 per cent nickel in the old 'nickel' is now in circulation. The manganese had to be added to reduce electrical conductivity to the level of the older coin, so it could be used in slot machines. The Treasury is ready to begin minting pennies and a new 3-cent piece of zinc-coated steel to save copper.

Molybdenum is used instead of tungsten in a tough alloy for cutting steel with steel. Stainless steel mobilized with silver alloys becomes more stainless and more workable.

Self-lubricating iron bearings, saturated with oil, used in place of bronze, save copper.

In a new process for chlorinating paper pulp, the method of application ensures a uniform mixture of chlorine and pulp and greater efficiency in the use of chlorine. Dresinate, a wetting and emulsifying agent, has been developed for use with alkaline metal cleaners, to replace some of the chlorinated solvents, now scarce because of chlorine shortage.

Nitroparaffins, made by treating propane with nitric acid, may bring a revolution in the paint industry. A cork substitute has been made from sugar cane, felted into boards and laminated with weather-resistant asphalts.

Wheat germ, suggested as a war diet substitute for cheese, beefsteak, etc., has been found as good or better than casein for maintaining growth.

New oils made from linseed and soybean are replacing tung oil in quick-drying paints. Peanuts and soybeans are becoming key United States crops and finding continual new applications. With coconut oil imports from the Philippines cut off, domestic sources of oil gain in importance.

New strains of sesame, important for its oil, have been obtained by treatment with colchicine. They produce approximately the same number of seeds, but 56 per cent larger.

The full-scale commercial production of a new synthetic quick-drying oil called Conjulin, made by isomerization from linseed and similar to tung oil, has been started.

Metals and Minerals.

The huge increase in armament for our mechanized army has brought steel and other metals to the scarce list.

The United States in 1942 produced more than a 1,000,000,000 lbs. of aluminum and next year expects to make 2,100,000,000 lbs., 63 per cent more than world production in 1938. A new aluminum industry is springing up near the Pacific coast. Recent developments have been a new lighter stronger alloy, a process for making forged aluminum cylinder heads for aircraft engines, new and improved methods of fabricating aluminum, new chemical and electrochemical finishes, as well as synthetic resin coatings, and new processes for using low-grade bauxite ore.

A new process recommended to the War Production Board makes it possible to include a substantial quantity of clay with low-grade bauxite ore in producing alumina.

A new ferrosilicon reduction process for production of magnesium from dolomite uses relatively simple equipment and the reaction proceeds smoothly and without hazard. Several companies are interested in putting it to work.

A welding process that will make possible all-magnesium airplanes has been perfected. Magnesium is being reclaimed by a new welding method, using helium.

The Bureau of Mines has done a great deal of investigation and exploration this year, swelling estimated mineral reserves of chromite, manganese, mercury, iron, tungsten, nickel, bauxite, and higher-grade alumina clays by more than 32,000,000 tons. Production of helium was increased more than 3 times over 1940. WPB authorized construction of 5 mills to produce flake graphite from American deposits. Topaz from South Carolina was found to provide a suitable substitute for Indian kyanite in refractories. A pilot plant is to conduct tests of a gas-reduction process for making zinc, and another to test methods of producing sponge iron, to provide low-carbon iron in place of scrap. Sponge chromium 99.8 per cent pure, should be valuable in the manufacture of special steels, brass, and bronze materials.

A new source of vanadium found in the phosphate ores of Idaho, is estimated at 6,000,000,000 tons, enough to make this country self-sufficient.

Experiments are now under way on a new steel made without chromium, that can be electrically welded into seamless tubing on available equipment.

Metallurgists have developed five new blended hardeners for steel, using boron and small amounts of aluminum, which are expected to ease the alloy steel shortage.

It has been found that iron can replace all nickel and a third of the copper in printing plates.

Miscellaneous Developments.

A very unusual ceremony took place in Chicago November 20, when Vladimir N. Ipatieff was honored on the occasion of his 75th birthday, which was also the golden jubilee of his career in chemistry and his golden wedding anniversary.

Synthetic cellobiose, the fundamental building block of cellulose, has been made. This will give scientists a better knowledge of how cellulose is put together and enable them to use it more effectively.

The synthesis of lactose was announced by C. S. Hudson of the United States Public Health Service. Its structure had been known for some time, but it had never been synthesized previously.

Synthetic p-cymene, useful as an intermediate in the manufacture of phenols, thymol, and menthol, was announced, and a plant to make it is under construction.

The need for nickel and cobalt for wires in certain types of vacuum tubes was eliminated by the development of an iron-glass seal. A series of glass compositions has been devised which can be used with iron and certain iron alloys, because the rate of expansion is very close to that of iron.

A porcelain glaze for insulators has increased the strength of porcelain more than 100 per cent, made manufacturing easier, and imparted better weather-resistance.

Plastic lenses for cameras and spectacles can be protected from scratches by a glass film a few thousandths of an inch thick.

Mass production of precision lenses for microscopes, projectors, and other optical instruments has been made possible by a scientifically controlled process of heat-treating optical glass.

Sandless glass containing compounds of tantalum, tungsten, and lanthanum with boric acid is now being made on a small scale. Used in aerial cameras with compound lenses, it gives better definition over a wider area with no loss of lens speed.

Microphotography now has its own journal, The Journal of Documentary Reproduction. A new type of safety microfilm is an ultra-fine-grain panchromatic negative film with a high inherent contrast and outstanding resolving power.

Electron microscopy, newest of research techniques, received a stimulus at the first formal meeting of its devotees in Chicago at the time of the Chemical Exposition. The National Conference of Electron Microscopy was organized there and officers elected. New instruments, smaller and more easily used than previous models, are now available.

Infrared rays are being used to dry textiles after dyeing and finishing processes. Dyes have been made directly from soft coal, instead of from coal tar.

New chemical products for crime detection include a developer for latent fingerprints, and a fuming apparatus for developing fingerprints on greasy surfaces and fabrics.

Improved synthetic camphor yield is seen in a recent patent that deals with new technique for increasing the yield of an important intermediate, bornyl chloride.

New applications of melamine resins are in buttons and in treatment of paper pulp to impart great wet strength to the sheet and increase resistance to folding.

Pliofilm is being used in airplane and similar industries to hurry fabrication of templates.

Celastic, a colloid-treated fabric, affords quick repairs and alterations for patterns of metal castings, speeding military production.

A new fumigant for grain and flour, chlorinated nitroethane, is highly penetrating and deadly to insects but harmless to humans.

Levulinic acid, formerly a laboratory curiosity, has been made from cornstarch and may find uses in industry and medicine.

New synthetic plant hormones have been prepared at the Boyce Thompson Institute from organic acids by addition of atom groups containing chlorine, bromine, and iodine. They cause formation of seedless fruits and induce profound changes in growth.

Bromelin, an enzyme from pineapples, is used to make tough meats tender.

Bubblfil is air trapped in a continuous stream of cellophane bubbles. It is buoyant as kapok and is used in air compartments of lifeboats and life rafts and in pontoons.

Foamglas, weighing 10 pounds per cubic foot, can be sawed and drilled, and is being made in commercial quantities. Because this glass will float, it is finding use in lifesaving devices of the Navy and Air Corps.

Aqualized paper fabric, a substitute for cloth and burlap, is made by interlocking and fastening individual fibers, giving inherent wet strength independent of coating or sizing.

Waxy starch from selected strains of corn and sorghum may replace imported tapioca in textiles, industry, and foods.

Smokeless powder is now being made from wood cellulose pulp as the result of a new process. It is estimated that the development will save the United States Government $20,000,000 in 1943 and will free Canada and Australia from dependence on cotton.

1941: Chemistry

General Survey.

Our best estimates indicate that during 1941, 1,008 American manufacturers expended about $117,500,000 for scientific research, and of the companies included 49 per cent provided a larger budget for investigation than in the preceding year and 43 per cent the same amount. Twenty representative manufacturers expended 2 per cent of gross income from sales of nondefense products for research and developmental activities. While all these manufacturers are not in the chemical industry, enough are to show the maintenance of the former trend to rely upon scientific activity for the production of new and improved products. A check on new products displayed at the biennial Chemical Exposition held in New York in December 1941, showed that new chemical compounds had been manufactured at the rate of 400 a year since the preceding exposition.

In a year such as 1941 it might be expected that few new products would emerge from the developmental stage because of the necessity of devoting such a large proportion of effort to production of already established lines. The demand on the chemical industry for products used as such in defense and for those contributing to other lines of manufacture has been great indeed, and the volume of goods required is difficult to comprehend. Now that the United States is at war, such statistics are necessarily withheld from publication. It may suffice to say that even the chemical manufacturers themselves find it difficult at times to realize that such quantities of materials as are ordered can actually be required. And yet, as the arsenal for the democracies, the United States may expect to be called upon for even greater quantities of essential materials in the days and months to come. It is surprising therefore that so many new things have made their appearance. More than that, it is well known that in many companies there have been put aside, in a practically finished state, new items ready for introduction when the war is over and when something useful and attractive may be required to stimulate a new peacetime demand, in addition to older products that can then be made available in large volume to satisfy a waiting market.

The Sulfa Drugs.

In the field of health, undoubtedly the continued development in the so-called sulfa drugs must rank high indeed. Having been so recently introduced, only five or six years ago, it is startling to learn that for the year a production of 740,000 pounds is expected. That seems an impossible quantity of any drug material until one learns that the estimated production of aspirin for 1941 was put at 5,300,000 pounds. Sulfadiazine, one of the newest of the group, is reported as useful in all of the diseases treated by previous sulfanilamide derivatives, especially diseases caused by B. hemolytic streptococcus, staphylococcus, pneumococcus, meningococcus, gonococcus, and B. coli. It possesses the advantage of much lower toxicity than other drugs of comparable potency and consequently may be used at more effective blood levels. Spreading sulfadiazine directly on burns has been found to be the most effective method of treating yet devised, and it is looked upon by some specialists as a treatment which may eliminate the need for skin grafting and plastic surgery.

Sulfaguanidine is reported to be effective in the treatment of various bacterial diseases of intestines, such as bacillary dysentery. It is absorbed in the blood stream only slightly and so may be given in high dosage to secure action on intestinal organisms without reaching toxic levels in the blood. On every hand one hears of remarkable cures effected through the use of some member of the sulfa drug family and changes in procedures made possible by their use. The use of the pure drugs as a powder or dust to prevent dangerous infections following abdominal operations is but one instance. It has also been predicted, based on scientific work, that the sulfa drugs may free the Americas from dependence on non-American sources of quinine.

Developments in Metals.

In the field of the metals, the big event of the year was the successful operation of the plant at Freeport, Texas, for the separation of metallic magnesium from sea water. In this operation lime is prepared from oyster shells and used to precipitate the magnesium as the hydroxide from the sea water. This is later converted to magnesium chloride by the simple process of adding crude hydrochloric acid and after proper treatment the magnesium chloride is fed to electrolytic cells where it is dissociated into the molten magnesium, with the liberation of the chlorine, which is recovered for re-use. The plant has been greatly enlarged during the year and further plans are being actively pursued as the new year opens, in order that ever-increasing quantities of this strategic metal may be produced to meet the requirements of war.

The magnesium development is interesting from many points of view, for it had its beginnings in the United States in the separation of the metal from the brines of northern Michigan, at a time when magnesium was not appreciated and found little if any market in this country. Patiently developed, the process has become of vital importance to the country and the metal once spurned by manufacturers is now in the greatest demand.

The year has also seen a remarkable expansion in the production of aluminum, by the process long ago developed by Hall and using the same raw materials, although of course there have been many improvements in the original method. During the year the Tennessee Valley Authority and research workers at Columbia University reported success with experiments looking to the separation of aluminum from clay. This is not a new problem; it has been undertaken by many previous workers. It has long been recognized that aluminum is one of the abundant elements in the earth's crust, and in some percentage is to be found in nearly all clays, but to separate it in a form suitable for electrolysis or other method of final separation from other elements has proved a most difficult job. And it still remains to be seen whether the newest processes prove successful.

There has been great activity in the metal fields, where pressure for increased supplies has been so great. Coatings like zinc and tin, ordinarily applied by hot dipping, were greatly reduced in thickness and consequently in the amount of metal required by electroplating. Especially in cases where the final protective coat was to be a synthetic resin, this was found satisfactory as well as economical.

Powder metallurgy received a considerable impetus, and the production of parts made by this newer method of compressing metal in powdered form into desired shapes, ran into some thousands of tons.

Silver, which has frequently been on the borderline between a precious and an industrial metal, found some new applications in the industrial field. It was found to be a satisfactory substitute for copper in electrical contacts, was used as an alloy with magnesium, as a substitute for chromium and nickel when plated over copper, and as a lining for some chemical equipment, thereby decreasing the requirements for stainless steel. A technical report made to the Government showed that from 2.5 to 5 pounds of metallic silver could replace as much as 40 pounds of tin in a type of solder. With tin becoming increasingly scarce and with an abundance of silver in the country, it was an entirely economic procedure.

Vitamins.

If interest centers on vitamins, then surely 1941 ranks high among the banner years. Some fifty industrial research laboratories have been engaged in the vitamin studies. The geneticists have undertaken to increase the vitamin contents of certain useful plants. Molecular distillation has made possible the preparation of concentrated vitamins from fish and other oils, and by chemical processes carotene has been isolated from dehydrated alfalfa leaf meal. A new member of the vitamin B complex, folic acid, was isolated, and nutritionists took the lead in adopting a program for the vitamin enrichment of foods, particularly flour. It became generally recognized that while in America a proper selection of foods would supply adequate vitamins, it was also true that in many instances a vitamin deficiency in the diet exists regardless of the economic level of the family, because of ill chosen diets. Capsules and a complete daily ration of all needed vitamins in other forms made their appearance, and in some areas vitamins were offered in somewhat unexpected forms, such as dried grass, which had been found to contain a large percentage of these important food factors. Frozen grass for chicken feed was one of the totally unexpected introductions. The synthesis of the vitamins continued and perhaps half of the recognized individuals in the vitamin series have now been prepared in this fashion.

One group of investigators reported the first success in achieving a marked darkening of previously gray hair and the growth of new natural colored hairs in 30 human beings by employing one of the newest members of the vitamin B group, p-aminobenzoic acid.

Synthetic Resins.

Vinylidene chloride, better known as Saran, and first used as a decided improvement on rattan because of its resistance to wear, its non-absorptive characteristics and its high tensile strength, was found superior to metal when extruded as small threads and used for fly screens. Later, the resin in the form of small tubes, which are used extensively in refrigerators, automobiles, and many other places where oil lines, air lines, and other connections for conveying small quantities of gases or fluids made its appearance. Coming at a time when copper tubing is almost nonexistent because of defense priorities, the innovation is particularly welcome.

Synthetic resins have been found useful in preventing the surface scaling of cement and for the elimination of plywood. Its utility has led to large-scale experiments for the replacement of thin metal, going as far as parts of automobile bodies and airplanes. Considerable progress has also been made in developing entirely new groups or families of resins, some of which exhibit surprising resistance to surface abrasion, something which has held back their use in the replacement of glass for special purposes, such as airplane windows and possibly windows in automobiles.

The scarcity of metals for nondefensive uses led many manufacturers to turn to some of the large number of synthetic resins and plastics for substitutes, and with considerable success. In many cases it is doubtful whether when peace comes again the manufacturer will return to metal for the manufacture of many parts which heretofore he has regarded as necessarily made of some one or the other of the metals.

A resin made from pine wood practically eliminates surface scale on concrete highways, which means the breaking off of from 1/16 to  inch of the road surface, thereby exposing the coarse aggregate to the deterioration caused by the rapid alternate freezing and thawing of the material.

Synthetic Rubber.

Turning to another field, progress in synthetic rubbers, or more correctly synthetic rubberlike plastics, has been rapid and important. Four plants, each of 10,000 tons annual capacity, were undertaken, only to be trebled in size before much more than past the blueprint stage. Two companies announced tires made wholly of reclaimed rubber, following several years of research, and interest was revived in the possibility of obtaining rubber from the guayule plant, which grows in semiarid regions. Notwithstanding these efforts, the demand for the defense uses of rubber grew to the point where serious dislocation of the American method of transportation must be faced in the near future.

The experiments conducted in the Soviet with koksagyz, a variety of dandelion, may become interesting in the rubber problem. The latex which it bears is said to be satisfactory. In 1940 an area ten times as large as in 1937 was devoted to this plant and some thousands of acres were being added in 1941. The plant can be utilized the first year.

Petroleum.

The oil industry gave an excellent account of itself in 1941, with all production records exceeded and new products made on a large scale. One hundred octane aviation gasoline was made in increasing quantities with at least a threefold increase a problem for the immediate future. For the first time trinitrotoluene, required in the manufacture of one of the most powerful explosives, was produced in large quantity from petroleum as a raw material, and here again the volume must be multiplied. The production of the principal raw materials for the manufacture of synthetic rubber was also a problem of the petroleum industry, which must meet a demand at least beyond any present calculations.

While the reserves of petroleum were determined as probably the greatest in our history, thanks to improved methods for locating new fields, for obtaining oil from wells, and the processing of crude, it was nevertheless reassuring to learn from work on coal hydrogenation that Pittsburgh bituminous coal could be made to yield two tons of oil from each three tons of coal so processed.

Among the progressive steps in the gasoline industry should be mentioned the use of small amounts of sulfur dioxide along with a reforming catalyst in the treatment of hydrocarbon distillates to increase their antiknock value.

Molecular distillation, such as is employed in the production of vitamin concentrates, has also been employed in the petroleum industry to separate constituents that have boiling points rather close together. The process makes possible the separation of naphthenic and paraffinic base oils with a much sharper line of demarcation.

Production of Chlorine.

Much attention has been given to chlorine because of its place in the defense program. The production capacity of the country is large indeed, but more and more chlorine has been in demand, which has directed interest to new methods for its manufacture and revived interest in some of the older non-power-requiring procedures. One research group proposed to produce chlorine by the interaction of sulfur with salt, which by their methods leads to the production of sulfur dioxide and chlorine, which must then be separated. One manufacturer, to assist in the situation, redesigned his process which used chlorine, so that he might substitute hydrochloric acid to be made by the old process of treating salt with sulfuric acid. Still other manufacturers have conducted independent research on the general problem of chlorine production without the use of power, no longer available in large quantities at the places where chlorine should be made for its most advantageous utilization.

The great demand for chlorine in other directions has made it necessary for the paper industry either to adapt natural shades to its uses or to improve efficiency of the chlorine used in bleaching. The latter has been accomplished in some instances by submitting the pulp to the bleaching action of the chlorine for a longer time than is customary, and in others by the addition of a hydrated sodium metasilicate. The addition of 1.5 per cent of the silicate based on the weight of the air-dried pulp, gave the same degree of whiteness with a 15 per cent saving in chlorine.

A new robot chemist that automatically and continuously measures the amount of chlorine required by city water supplies was perfected after more than ten years of experimentation. Formerly chlorine was added merely in proportion to the amount of water being used, and regulation was only possible by means of continual routine chlorine analysis.

Glass.

Glass fiber, developed the last few years, took an important place as an insulating material, although previously it had been frequently used in such a role. By its application in place of other insulating materials, more than 60,000 pounds was saved in the case of a battleship and small motors were able to do the service of much larger ones. Glass cloth impregnated with suitable varnish has also been found useful in the electrical industry and the cloth itself was more extensively used in the new weaves and patterns for draperies, table covers, and the like.

A method of electric welding for the repair of glass was developed and was also used in manufacturing items from glass parts. Ultraviolet radiation for the sanitization of bottles was also employed. For the attachment of safety glass, made as is well known by the use of a layer of plastic between two sheets of glass, a variety was developed in which the plastic extends beyond the glass sheets, so that it can be attached to window frames.

Optical glass is now being made using tantalum, tungsten, and lanthanum which possesses greater light-bending properties than those heretofore made.

Milk.

Milk as a raw material continued to have its share of attention. The problem has been somewhat complicated by world conditions. For example, there has been a shortage of casein because of the inability to ship this industrial material from South America for use in paints, adhesives, and paper coating, while concurrently the demand for dried fat-free or skim milk has greatly increased, with renewed recognition of its food value. The United States committed itself to deliver a great quantity of dried separated milk to Britain, and in November the announcement was made that a new textile developed here from the protein of milk had been perfected, following some four years of research and experimentation. Being less costly than wool, yet having many of its characteristics, the new fabric would seem to offer some competition in the demand for fat-free milk, which, although at times it has been produced in excess in this country, is at present difficult to obtain in sufficient quantities for nonfood uses.

Plant Products.

In the first World War charcoal for gas masks was made from dense plant products such as coconut shell and peach pits, but a process was developed for making a suitable char from wood as well as from coal, thereby giving the United States independence in this field of defense.

A new plant came into production for the synthesis of phenol from benzene, with much improved efficiency as its particular claim to fame, and with a greatly increased demand for phenolic type synthetic resins, this plant is being considerably enlarged for increased production in 1942.

Development of Textiles.

In the past comparatively little attention has been paid to the improvement of natural fibers such as wool. Research announced during 1941 indicates that one of our best known natural fibers — wool — can be made much more resistant to moths, alkalies, enzymes, and bacteria through a chemical treatment. The resistance of wool to various stresses is due principally to its springlike molecular structure. The molecules of wool consist of chains connected by links at frequent intervals, and these cross links are easily destructible. They are believed to be responsible in part for the shrinkage and hardening of wool in laundering and the sensitivity of the fiber to alkalies, and it is thought that it is these cross links that are most attractive to moths. At any rate, the accomplishment has been to break these cross links and so react them with chemicals that the broken links rejoin in a form that is more stable and is chemically resistant. The modified wool is much more resistant to moths, alkalies, enzymes, and bacteria, retains its original stretch and insulation characteristics, and has a feel similar to that of untreated wool. It is also much more resistant to shrinkage. This work ranks among the first to be done on this important fiber. With wool numbered among the strategic materials, it comes at a time of special importance.

While naturally somewhat more expensive than untreated wool, this new stabilized fiber will surely win a market for many types of clothing and household fabrics. The most immediate use, however, promises to be in the industrial felts required in the manufacture of paper. These felts are inclined to deteriorate because of the chemicals used in the process and of bacterial action in the fiber which is almost continually moist.

Nylon, so frequently discussed, continues to attract attention because of its further applications in its various forms. It should be remembered that nylon is a generic name and that the polymer is used in many different forms. It was first introduced as a bristle, later as a filament for fabric thread, has been employed in sheets and as a laminating material and now promises to serve as a bearing in machines. These bearings are said to require no oil for lubrication, to offer less friction to rotating shafts, and to be capable of carrying heavier loads than the conventional bronze, babbitt metal, or brass bearings. Bearings have been made heretofore from other synthetic resins, but they required some type of lubrication, had to be reinforced, and had other disadvantages which nylon escapes.

Sulfamic Acid.

A few years ago the commercial production of sulfamic acid, which has long been merely a chemical museum curiosity, was announced, and since then steady progress has been made in its commercial utilization. It has now been learned that such objectionable plants as ragwood, so feared by hay fever victims, and poison ivy, can be exterminated simply by spraying them with solutions of this acid. Moreover, sulfamic acid is reported as useful in flame proofing of insulating materials, clothing, and cloth generally, and has a place as well in leather tanning.

Agriculture and Foods.

The fields of agriculture and foods have greatly benefited by the researches reported during 1941. The loss of iodine from iodized salt has been serious in livestock feed, but it has now been found that very finely powdered potassium iodide can be waterproofed by milling it with 10 per cent of its weight of either calcium or magnesium stearate. The product is twice as stable in the presence of salt and yet is entirely absorbable in the digestive tract.

The use of by-products from the canning of cranberries continues to attract attention. Ursolic acid is now being produced on a pilot plant scale, an oil from the cranberry seed, and a hard wax from cranberry skins. The sodium salt of ursolic acid has mulsifying properties.

The trend in food preparation is interesting, for with fewer than 2,000,000 births a year, infant feed manufacturers are turning their attention to older children, and we may soon see foods especially prepared for those of middle age and the aged. Already 402 different kinds of canned food are sold in the United States, 85 being vegetables, 64 soups, 55 fruits, 36 fish and other sea foods, 32 meats, 21 juices, and 109 specialties. The war has revived interest in dehydration, for not only is there an increased demand for concentrated foods to be shipped abroad by various means, including the air, but a need for rations for parachute and ski troops as well as for service men generally.

Efforts are being made to process vegetables whole and to conserve color as well as flavor. The quick-freezing industry has grown. It has been learned that the addition of urea to the basal ration of cows definitely increase milk production. Quick frozen preroasted beef is a newcomer from Argentina, and it is proposed that dry ice (solid carbon dioxide) may be useful in tenderizing beef, the idea being that the carbon dioxide will repress bacteria and mold-forming organisms, while the meat ages. Enzymes from various plants, including the Osage orange, are being used for meat tenderization.

Considerable success has attended the use of naphthalene acetic acid as a spray in 0.001 per cent concentration to prevent the drop of apples. Applied at harvest time, such a spray delays drop for from ten days to two weeks, thus permitting better color to develop, saving in packing costs, and prolonging the time during which picking can be carried on.

A chemical preservative permitting farmers to bed up hay under variable weather conditions has been produced in a form of phosphoric acid suitable for preserving feed crops such as alfalfa and timothy. (See also AGRICULTURE.)

Other Developments.

The search for insect lures continues, as it has been demonstrated that insects are guided by their chemical scents to their favorite luring odor. When filter paper was impregnated with the preferred chemical compound, insects proceeded to make a meal of it despite its lack of other resemblance to leaves and its obvious indigestibility.

Synthetic starch was made from glucose and it was said to be the first case on record of the production of starch by any means except the action of plants themselves. The total amount produced by the investigators so far is in the neighborhood of two ounces.

Thus we see in briefest outline something of the continual progress being made by the science of chemistry in its service to mankind. The samples given are nothing more than indications and the complete story is a very much longer one. It is encouraging, however, to find that even under conditions which have existed, the work has gone forward more quickly, if anything, than in ordinary times, and considerable satisfaction can be derived from the promise of continuing contributions in the future.

See also articles on METALLURGY; PHYSICS; PLASTICS.

1940: Chemistry

Chemistry, both pure and applied, can be proud of its progress during 1940. While in some fields the accomplishments may not be so spectacular as in other years, others rank well with previous achievements.

Sulfanilamide and Its Derivatives.

For most of us matters of health and self-preservation still come first, and so we turn again to the spectacular results which have been obtained with sulfanilamide, and which are now being achieved with its increasing number of derivatives. The public has heard much about sulfanilamide and is inclined to pass over that word in the news—but not so the chemist. So far, more than fifteen hundred derivatives have been made, in the effort to find something better for particular applications, and especially some form or derivative of the drug that will be less toxic and at the same time more efficient in overcoming some infection. Beginning with sulfanilamide, we had an effective drug against the streptococcus type of invasion; then came sulfapyridine, with which to combat all the types of pneumococcus, which cause pneumonia; then sulfathiazole, effective even against the dread staphylococcus. Now another derivative gives great promise because with it the alimentary tract can be sterilized without enough of the compound getting into the blood stream to cause complications; and it is believed promising in still other fields of medicine. Another new derivative is a compound involving nicotinic acid, and the advantage claimed for it is effectiveness in reduced dosages, thereby avoiding the depression of the central nervous system that may be an undesirable effect of sulfanilamide on some patients. Late in 1940 a camphorated derivative was perfected, and for it, too, less toxicity than with the original drug has been found. Because of its high potency the dosage required is less than in the administration of sulfanilamide itself, and it has been found particularly effective in the treatment of pneumonia. (See also BIOLOGICAL CHEMISTRY; MEDICINE.)

Calcium Compounds.

Calcium is one of the elements essential to the maintenance of our bodies and in recent years much work has been done on forms easily assimilated in our metabolism. To calcium gluconate, now well-established in therapeutics, new calcium compounds were added during 1940.

Vitamins.

Vitamins still continue to hold their place in the scientific and public interest. One of the discoveries of the past year was that the form of blindness known as keratitis, a disease in which the cornea of the eye is invaded by a superfluous number of blood vessels, followed by the formation of white opaque spots that blot out vision, is caused by the lack of vitamin B₂ or riboflavin. Even more important was the discovery that the administration of this vitamin would clear up the spots and restore vision. Further, if the vitamin is administered in the early or incipient stages, it was found, the disease can be prevented from developing.

For a long time physiologists have emphasized the fact that in refining foods to meet the demands of modern diets, desirable vitamins are frequently lost, not to be recovered. A century ago when everyone ate whole-wheat bread this difficulty did not exist. It seems important, therefore, that foods can today be fortified by the addition of riboflavin or vitamin B₂, now available in large quantities and at a price so reasonable that it can also be added to stock feeds. It is produced by a new method involving the fermentation of starches and sugars. In Great Britain, where the people insist upon white flour, deficient in vitamins, bread will now be fortified with vitamin B₁ and a little calcium salt. It will be recalled that this vitamin, thanks to research in the United States, is now commercially available in whatever quantity may be required. Thus we find vitamins becoming available through the grocery as well as through the pharmacy.

Another source of vitamins is at least interesting and may soon become commercial. It was reported that edible vitamins are to be found in grass and that 12 pounds of dried grass contain more vitamins than 340 pounds of fruits and vegetables. All that remains is to perfect a method for drying grass without damage to the vitamins, so that it can be offered in a powdered form suitable for incorporation in foods. We have here an inexhaustible cheap source of these vital food factors.

Foods.

Foods will always have the attention of scientists. There is such a supply of foods new either in form or substance that a Food of the Month Club has been formed, offering to supply new items each month which the subscriber can try on the family.

One of the most important developments in the past fifty years affecting lard was the discovery during 1940 that its oxidation can be prevented. All that is required is the addition of an exceedingly small quantity of gum guaiac derived from a tropical tree. This preserves the linoleic constituents of the lard, a health factor of considerable importance.

Then it has been found that a little calcium chloride will stiffen canned tomatoes, so that they retain their shape and are consequently more attractive. The pure food regulations offer no bar to this procedure.

The turkey crop is more important year by year, but turkeys have their troubles, too. One of these is perosis, the name for slipped tendons. But if one pound of manganese in the form of sulphate is added to one ton of mash used as a feed for turkeys that are penned, the trouble is prevented.

Rubber.

A real headline for 1940 has been the development of so-called synthetic rubbers in the United States, and new progress in the use of rubber. Strictly speaking, these new materials should be called 'elastomers' or by some other name to indicate that they are not true duplicates of natural rubber. The molecules are not identical. But apparently the term 'synthetic rubber' has come to stay. What has been accomplished in rubber during 1940, the culmination of research begun much earlier, is probably from the point of view of applied science the most important development of the past year.

Synthetic rubber had been produced before, notably methyl rubber in Germany 25 years ago. However, it was disappointing in performance during the World War. Also prior to 1940 we had neoprene, Thiokol, and Koroseal, all American products available on a commercial scale and used because they could perform services impossible to natural rubber. For example, these materials resist the action of petroleum and its products far better than natural rubber; although they cost from three to six times as much, they have been in demand. Buna in different varieties, developed in Germany, has had much publicity and about half the requirements of the Reich had been met by this synthetic prior to the outbreak of the present war. Sovprene is the name of a similar product developed in the Soviet.

The announcements and introduction of new synthetic rubbers in the United States during 1940 were enough to afford an excellent example for those who contend that when things are badly needed inventors will produce them. Three new synthetic rubbers of American origin made their bow, all manufactured from raw materials to be had within this country: Butyl rubber is one, Ameripol another, and Chemigum the third. They are all products of gases derived from petroleum.

This is further evidence that petroleum, so long used only to produce fuels and lubricants, has become almost as important as a raw material for the chemical industries. If the United States is to embark upon a program for the manufacture of enough chemical rubber to make us independent of crude rubber, perfectly enormous quantities of butadiene made from butane, derived from petroleum, are essential. Butadiene can also be made from alcohol, as has been done in Russia, but petroleum is a more economical source. In addition, the patent rights to manufacture Buna, also from butadene, are owned here.

One should not jump to the conclusion that synthetic rubber is soon to be available in great quantity. Some 1,700 tons were manufactured in 1939, and with greatly increased production costs will be lowered. Compare this quantity, however, with the 592,000 tons of crude rubber used in the same year and some idea is obtained of what is involved in producing even an important fraction of so large a total. Further, it would be unwise to proceed with the construction of necessary facilities without the experience that comes from erecting one such plant, thereby learning improvements and avoiding costly mistakes in those to follow. The synthesis of this type of material is most difficult, and that it should have been accomplished in so many different ways at a time when the product assumes unusual national importance is indeed remarkable.

A rubber product, Pliofilm, found a new job in 1940, being used in the packing industry to prevent weight shrinkage. First used as a wrapper for meat loaves, it is now applied by means of a packaging machine to a wider variety of meat products.

Rubber advanced further into the printing industry in 1940 in the form of rubber printing plates on a Webb press. The new plates are particularly suitable for printing on corrugated or uneven surfaces or for high-speed work. They also make possible a 25 per cent saving in ink and a reduction of as much as 66 per cent in the time required for make-ready.

Rubber has also been introduced in a new type of armor plate, in which a special rubber alternates with thin steel sheets. The resulting armor resists bullet penetration equivalent to solid steel armor plate of 20 per cent greater weight. Weight saving is of course desirable not only in airplane armament but on the sea as well, and new applications are not impossible.

Metals and Their Applications.

Metals continually offer new opportunities, and these are by no means neglected. The sea has long been recognized as an inexhaustible mine for many materials. The plant of the Ethyl-Dow Chemical Co. at Wilmington, N. C., during four years of operation treated water equivalent to one square mile 354 feet deep or 634,366,000,000 pounds of brine. The chemicals in this vast amount were sodium chloride, magnesium sulphate or Epsom salts, calcium chloride, potassium chloride, aluminum, strontium carbonate, iron, copper, iodine, silver, and gold. If they could have been recovered and sold at current prices, they would have been worth over $383,000,000. In most cases, however, the cost of recovery would have been greater than their worth. The gold, 0.2 ton, was worth $168,000, but it would have cost more than that to extract it. Magnesium metal has become important, and in 1940 a $15,000,000 plant was built in Texas, to mine the ocean for this lightest of metals. The demand by aircraft construction is one of the reasons. The company has been producing about 2,500 tons of magnesium per year from the brines of Michigan. That amount has now been doubled, but with the completion of the new plant 12,500 tons will be the yearly production in the United States.

A new process for the recovery of aluminum from clay, the largest resource of this metal, has been announced. We now depend on bauxite, the ore which has always supplied us. If clay can be used successfully, it will indeed be fortunate.

Cable sheathing produced to the extent of $10,000,000 annually is ordinarily lead hardened with antimony, one of the strategic materials coming mostly from China. It has now been learned that calcium will harden lead, and the result is superior to the antimony lead. A smaller percentage of calcium than antimony is needed and there is less tendency for the alloy to crack after long use in cables.

A new type of dustless and sliverless copper was perfected during 1940 to meet the need of the electrical industry for a metal free of the imperfections of ordinary copper. Ordinary copper is held responsible for the penetration of insulation and for a considerable percentage of failures caused by short circuits. The new copper approaches the malleability of gold, has greater ductility than ordinary copper, draws easier, and is a better conductor of electricity.

A new nail was offered last year, made from rust-resisting Monel metal. These nails are provided with a number of grooves that so increase their holding power in wood as to give better service than wood screws. They are particularly intended for marine work where their rust-resisting properties are highly valued.

A new magnetic alloy of cobalt, vanadium, and iron, that can be drawn and rolled, also made its bow. Polonium, one of the radioactive substances, was incorporated to advantage in the electrodes of spark plugs, and the element indium was produced in commercial quantities and found to play a very important part in bearings and on other surfaces subject to friction.

Petroleum.

Among the developments in the petroleum industry should be noted the increased production of aviation grade gasoline, the award of a contract for a plant to produce toluene for explosives from petroleum, and a patent for the production of high quality gasoline from paraffin wax. This last is accomplished by the action of heat of 850° to 1,000° F. and a catalyst such as an acid-treated clay of the type used for decolorizing lubricating oils. Distillation follows and the yield of high grade gasoline is about 40 per cent. The possibility of producing gasoline from vegetable products and from seaweed was the subject of a paper before the American Chemical Society. The carbohydrate materials—that is, products rich in starch or sugar—are heated under pressure with limestone. There is no idea that the farmer will in future produce his own gasoline, nor is it possible for fuel produced by this process to compete with the low cost of gasoline from crude oil. However, it is contended that fuel can be made cheaper by such a process than by the hydrogenation of coal, which is the German method and which requires expensive high-pressure equipment.

By feeding oxygen into the intake air, it has been found that the power of Diesel engines may be increased 55 per cent for the few minutes required to help the take-off of Diesel-equipped planes. This can be done without detonation or undue strain, and means that the weight of the engine can be reduced by one third.

The advantage of using 100 octane gasoline for ordinary motor cars and busses has been stressed and experiments show a 55 per cent increase in mileage per gallon over the 70 octane now in use at speeds of 20 miles an hour. At higher speeds the gain is as much as 40 per cent. If the cost of manufacturing high octane gasoline were twice that of ordinary fuel, the economy would still be in favor of the better gasoline. The airplane demand is such, however, that it may be some time before the ordinary motorist can take advantage of this economy.

Color.

It is interesting that a chance discovery has revealed the fact that color-blind men in airplanes are able to see through all types of camouflage so far developed. Also, color photographs taken from plane at night will penetrate camouflage that might hide military objectives from ordinary reconnaissance photography. (See also PHOTOGRAPHY.)

Plastics.

Plastics have continued to make an enviable record. Vinylidene chloride, trade-named Saran, has crude oil and salt brine as its parents. The product as first manufactured consists of so-called fibrous crystals in heterogeneous arrangement. At this stage the plastic has only ordinary properties and a tensile strength of about 8,000 pounds per square inch. However, when the fibrous crystals become oriented into linear patterns, the resin takes on remarkable properties. The strength is increased to 60,000 pounds per square inch, accompanied by great flexibility. The new resin has high chemical resistance and has already found its place in fishing tackle, as a binder for abrasive wheels, and in extruded threads which, woven, have been used as seat covers in some New York subway car equipment.

New applications of plastics include furniture, ladies' shoes, football helmets, and costume jewelry. Veneers of expensive and rare woods are used not only to mold various pieces of jewelry but to provide decorative finishes for vanity and cigarette cases, table tops, baggage, and even wall panels. Interior walls of a room may now be had in one piece; and a wood veneer laminated with one of the synthetic resins is now provided in pieces up to 8 x 20 feet into which it is only necessary to fit window and door frames. Joints, cracks, and other features unsatisfactory for finishing are absent, and one side is provided with a cloth surface to facilitate the type of preferred adornment.

The use of plastics in molding airplanes has received much attention and a 2,050-pound, low-wing monoplane trainer was built. This was composed of triple laminated spruce plywood, impregnated with phenol resin plastics. The parts were made in molds and then baked under pressure. Riveting and welding are eliminated in such construction, and if the process can be applied commercially and the airplanes prove satisfactory in use, the production rate will be 20 times faster than for metal aircraft. At least four aircraft companies and two research laboratories are working on this problem. (See also PLASTICS.)

Glass.

Much interest was aroused in 1939 in the possibility of increasing the transparency of glass by giving the surface a very thin coating. The first commercial application was in projection lenses, where the utmost light was desirable with colored movies. The difficulty with that development for show windows was the nonpermanent character of the film. This objection has been somewhat overcome by the most recent developments. Meanwhile a new method has been introduced in which, instead of treating the surface of the glass to form a thin film, the oxides in the glass surface are dissolved from a very thin layer. This has been found possible without damage to the surface polish, just so long as the solvent does not take out the silica. Telescopes, and photograph lenses are likely to be the first beneficiaries.

A new glass has been devised for use with X-rays. It is laminated with the center of the sandwich a piece of glass high in lead oxide. Progress was also made in the manufacture of mirrors. Spray methods for applying the silvering solution were perfected, with higher quality and lower cost two of the results. The process is continuous, with no manual handling involved.

Pulp and Paper.

In the paper field the use of new species involving some change in the chemical processing of the pulpwood potentially added much to our resources. It was found that contrary to accepted ideas, white pine can be grown as rapidly in New England as loblolly and slash pine in the South. Improvement in bleaching pulp, using sodium chlorite, now available commercially, is expected to make the United States independent of Scandinavian wood pulp. This chemical compound, commonly called chlorite, has the unusual property of bleaching wood pulp, cotton, rayon, and other materials extremely white without weakening the fibers or causing the loss of other desirable properties.

Improvements in bleaching what is called sulphate pulp, now made in great quantities, make it possible to replace sulphite pulp in some papers. This again broadens the resources from which pulp satisfactory even for ledger papers may be made, and the strong sulphate pulp can compete with sulphite in the production with ground wood of newsprint. (See also PAPER AND PULP INDUSTRY.)

Containers.

The tin situation, as well as continued competition in the container industry, has led to further developments. Reports are that there is not more than a year's supply of tin in the country, and it may be some time before tin is refined here. Further steps have been taken in the use of plastics or synthetic resins to line cans of untinned iron which are generally decorated with aluminum paint, producing a can satisfactory for many purposes. New designs of glass bottles, in which a stronger glass is used, have made possible the competition of the bottle with the single-service fiber container and even with the can.

A container of Pliofilm and cellulose acetate has been introduced for food products. This is a light-weight transparent package held in a cardboard carton and presents advantages of its own as a single-service package.

Paints.

Progress continues in the field of protective coatings and methods for their application. The effort continues to produce paints of germicidal value, and it is known that a halogenated oil containing 4 per cent chlorine, when added to linseed oil for paint, possesses the highest germicidal value, but even this is not great. New paints were introduced for rooms with health lamps. Most paints reflect less than 10 per cent of the ultraviolet light from such lamps, but a new one was introduced that will reflect up to 72 per cent of these beneficial rays.

Most paints, lacquers, and the like are applied with the help of a vehicle. This, of course, introduces drying problems, which vary with the type of coating employed. More enamels are being used than formerly, such as on reflectors and even automobiles. Infrared rays, which are the heat rays of the spectrum, are now applied commercially, using old-style carbon filament lamps with gold-plated reflectors, so that an automobile may almost be said to proceed through a gold-lined tunnel as the finishing step in its decorated exterior. A new enamel called Ethomelt avoids the use of vehicles altogether and is applied hot.

Textiles.

Nylon made its commercial bow in May and the stock of women's hose that had been accumulated for the event was cleaned out of most stores in a few hours. Since then there has been difficulty in maintaining stocks. It is well to remember that the women of America use 50 million dozen pairs of silk hose annually, and that the nylon fiber available could account for somewhat less than 10 per cent of that number during 1940. However, new facilities for producing the fiber have been under way and a new plant is in process of erection, so that by the end of 1941 or early in 1942 five times the originally planned output of fiber will be made, some 16,000,000 pounds annually. And there will be represented in equipment for the manufacture of nylon fiber some $28,000,000. Notwithstanding this demand, a price reduction in nylon yarns was made in October, in conformity with the policy which exists in the chemical industry to reduce prices as rapidly as large-scale production makes it possible.

Improvements in nylon have been announced. It has been made tougher and stronger by a tempering process—more important in the case of bristles, films, and rods than of fibers used in hosiery. The tendency of the fiber to darken when subjected to heat and light has been overcome by a new process, and a derivative of the first material has been made resistant to long contact with acids and alkalies. Another advance has been to render nylon permanently waterproof, so that stockings made from it are splashproof. Open-toed shoes put added stress on stocking toes, and now the hosiery can be reinforced with nylon-covered elastic toes. The versatility of nylon is further demonstrated by its use in photographic film, where its great strength enables thinner film base to be made and with much longer service life. Wool-like fiber of nylon is made, and still other forms are possible. Vinylidene chloride, mentioned elsewhere, is also a fiber base, and a competitor named Fortezan is in the offing. The latter is said to be stronger and more elastic than the first truly synthetic fiber.

The fiber produced from the casein of skim milk, first publicized in Italy, and now made here, was used as a supplement up to a maximum of 10 per cent with rabbit fur to make high quality hats. This came at a time when the importation of rabbit fur was disturbed by the war. It is said that between one and two million pounds of such fiber will be required annually for hat making. It is interesting to add that material for a woman's dress requires casein from thirty quarts of milk. There has been further work on similar fibers from the protein in soybeans, and cloth containing 30 per cent of this fiber with 10 per cent of mohair and 60 per cent of wool has been made for upholstery in automobiles.

A new method for mercerizing cotton fabrics, so that the material has a high sheen and a soft feel and is practically shrinkproof is now utilized. Improvement in mothproofing is reported. The new process holds the proofing reagent chemically bonded to the wool and the fabric can be repeatedly laundered without losing its moth-resistant properties. Just as mothproofing agents are made a part of the fiber, a patent has been issued covering the precipitation of synthetic resins within a fiber of cellulose acetate yarn to increase its resiliency and render it substantially creaseless.

A carpet that glows in the dark has been developed for sleeping cars, theaters, and other partly illuminated places. Dyes that absorb invisible ultraviolet light and reflect it as visible light are the secret of this material. The dyes are used to treat the wool before the carpet is woven and the details of the pattern stand out strikingly. Special lamps fitted with filters allow only invisible ultraviolet rays of the light to pass. Concealed in the ceiling and walls, they are not seen by patrons. Greater safety and the elimination of shaded aisle lights are other advantages. (See also TEXTILES.)

Other Developments.

To the multitude of uses to which synthetic resins have been put, add water softening. So far this work has been done with water which is not very hard. The investigation of course continues, and perhaps some day we shall see sea water made useful in household and industry by some such process. Synthetic resins also are employed to add strength to paper, especially when it is wet. We think first of paper towels in this connection, but there are other applications and the paper that is strong when wet will display even additional strength when dry.

An innovation in ink has been the introduction of a solid ink, one that is applied without oil or other vehicle and sets up without striking through the paper when cold.

Whey is a by-product in the manufacture of cheese. It may now become a raw material for a new type of wine. Yeast and sugar are used with the whey and the result, a type of Sauterne, improves with aging in the wood and clarification is helped by a cold shock. The new whey wine can also be produced in sherry flavors and contains 15 per cent of alcohol by volume.

It has been proposed that to protect ships' hulls from rust and barnacles the hull be submerged in water containing magnesium and calcium salts in the proportions in which they are found in sea water. Electric current is then passed through the water, so that the hull becomes the negative electrode. This would cause a coating of calcium and magnesium to be deposited on the hull. These coating are said to prevent the corrosion of the underlying steel and to make it more difficult for barnacles and other growths to establish themselves.

Colchicine helped produce the first new flower ever created by the use of a chemical—a tetra marigold. The new plant, 2½ feet high, bears very deep orange flowers, much larger than the parent flowers. The chemical has also been shown to have a beneficial effect on such trees as aspens and larches, trebling their size in young plants. Bigger trees mean more wood and cellulose for industry.

Riboflavin made eggplant grow faster and larger, while synthetic vitamin has caused unusual gains in the growth of tobacco. Tests with vitamin B₁ failed to prove that vitamin to be as useful with plants as some had claimed.

A new explosive prepared from butadiene derived from petroleum and ozone, a special form of oxygen, was announced. Another innovation is the use of water in place of explosives in some coal mines. Tubes covered with metallic braid are inserted in drill holes filled with water, which is then compressed to expand the tubes. This expansion breaks the coal and the hazards of explosives are avoided, as is the danger of gases resulting from explosives. The tubes are good for 2,500 tons of coal before they break.

The above citations are only indicative. The story cannot be made complete, nor can we give full details to show just how important some of these accomplishments have been. The emphasis now is on problems important in national defense.

1939: Chemistry

Chemically speaking, the year 1939 was reasonably prolific as measured by new products and progress in general. The chemical companies maintained their position as consistent performers in the payment of dividends, reduction of prices, and enviable records as to wages and hours and minimum of labor difficulties.

Textiles and Fabrics.

Nylon.

Although announced as a discovery late in 1938, the synthetic resin nylon should be regarded as a product of 1939. It is an example of the work which is most typical in the chemical industry. The first of the truly synthetic fibers, nylon was developed as the result of fundamental research undertaken primarily to supply in the literature missing data with respect to the polymerization of organic chemicals. This work began about 1930 and on Dec. 15, 1939, the first commercial unit for the production of the fiber began operations at Seaford, Del. Those who have previously discussed the time factor in the earning of profits from investment in research have set seven years as the average interval. Here is a case of nine or ten years in a difficult field, with profits yet to be earned.

In the research on polymerization it was found that certain small molecules could be linked together to form molecules of comparatively great length. While removing molten samples of this compound from an experimental still, researchers noted that the molten mass could be drawn out in the form of a long fiber and that even after the fiber was cold it could be further drawn to several times its former length. Such a phenomenon had never before been observed, and the incident led to further research toward a practical goal, while the general study on the polymerization of organic chemicals continued. The result, after many experiments, is the polymer made principally from adipic acid and hexamethylenediamine to which the name 'nylon' was given.

The great strength of nylon, its elasticity, fineness of fiber, the ability to make it also in the form of bristles, sheets, etc., have attracted wide attention. It has been commercially available, first, as bristles for tooth and hair brushes, for fish leaders and lines, and for sewing thread. Fair quantities produced by the experimental plant in the form of fiber have found their way into hosiery and, more lately, underwear, so that many severe trials have been possible. The resistance of the thread to breakage and to attrition makes it unique and promises to provide for the first time a successful competitor for natural silk. Dyeing problems, at first difficult, have been overcome and it was announced that more than five hundred dyes were available, to give this new synthetic fiber such tints as market or fancy might demand.

Vinyon.

During the year another synthetic fiber made its appearance, named 'vinyon.' This depends upon the early vinyl resins as its raw material, and they in turn upon acetylene and chlorine. Vinyon is a thermoplastic, and at present its future seems to lie more in the field of industrial fibers than in that of wearing apparel. Its resistance to many alkalies and acids, in the strength commonly met in industrial plants, marks it as one of the most successful filter cloths yet devised. In a fused form on cotton fibers it has made possible the first successful cotton felt. Its use as a binding agent promises to make cotton felt the first real competitor of wool felt.

Ethyl Cellulose Rayon.

Ethyl cellulose rayon, is a new textile fiber, more resistant to alkalies than many others. This is advantageous in laundering. Ethyl cellulose and also methyl cellulose, made this year for the first time in America, also have a wide range of application, particularly in the manufacture of paper, cosmetics, and food products as well as a finishing material for other textiles. So used it assists in improving the effect of dyes and improves the resistance of other fibers to alkali.

Rubber as Filtration Material.

Another interesting material for filtration is that made with rubber, utilizing its well established advantages of durability and chemical resistance. One material thus produced contains specific numbers and sizes of pores throughout its area. Another is a porous membrane having an extremely large number of minute openings. Obviously various combinations of pore sizes, numbers per square inch, gauges, and rubber compounds permit a flexibility in manufacture to meet the widely differing operating conditions in industry.

Processing of Textiles.

Advances were made in the processing of textiles to make them more moisture-repellant and to protect them from stains without interfering with the porous nature of fabrics. This is important in preserving proper ventilation for the body. Fabrics treated resist spotting by mud, ink, and ordinary liquids, causing stains, besides retaining longer their original freshness and are more subject to satisfactory cleaning. The use of synthetic resins in textile finishing to produce more creaseless fabrics also was extended.

Printing of Textiles.

Improved printing of textiles and new coloring of paper stock was obtained by colloidized dyes. This is one of the examples of the spreading use of the colloid mill in the chemical industry. Formerly ordinary grinding methods were used. Now it is possible to prepare water-insoluble lakes and vat dyes in such a fine state of subdivision that when added to water colloidal solutions result. In another type of printing, lacquers have long been used; but they were deficient principally in fastness to washing and in crocking. Pigmented synthetic resins, emulsified in water, have been prepared for this work. They are applied to the cloth on a standard printing machine and permanently fixed by a short cure. This method eliminates certain steps in processing, makes possible the absorption of the dye immediately after printing, and the use of very fine line engravings. Low costs combined with excellent fastness to light, washing, and crocking are obtainable.

Synthetic Resins for Miscellaneous Uses.

In addition to the synthetic resins so far mentioned, reference should be made to special resins developed for bonding mineral and glass wool, and others for brake linings. Further, an oil-soluble styrene resin for air-drying paints was introduced and further developments occurred in the use of certain resins for mounting biological and other specimens for permanent preservation. These resins are clear and colorless. The effect is pleasing and from all appearances the preservation will be perfect.

Improvements in dentures through the use of acrylic resins, and the appearance of Methyl methacrylate (trade name, Lucite) in forms to convey light to points desired by surgeons and dentists should be added to the list. The property possessed by these resins of conveying light without regard to the number of turns or angles from one end of a rod to the other makes them particularly valuable for this, not to mention the ease with which they can be sterilized. Large letters were fashioned from such resins for signs at the world's fairs and they began to be used for all sorts of decorative purposes, including toilet articles. (See also PLASTICS.)

Experiments went forward in the use of laminated plastics for the rapid production of airplane wings and fuselage of aircraft, and new plastics were produced from bagasse by hydrolysis in the presence of aniline and from waste lignin, present in the sulfite liquors of the paper industry. These appeared particularly interesting because of their very low cost and could be used in quantity where color is not a controlling factor. These resins are dark shades or black. (See also PLASTICS.)

Glass Products.

Fiberglas.

During 1939 Fiberglas made notable strides, particularly in the use of color for some of the fibers. Highly decorative materials in soft shades of blue and ecru made their appearance. Besides winning a market as electrical insulation, the lighter weight cloths of glass began to find acceptance on the part of hotel and restaurant owners because not only are the patterns attractive, but the material remains unaffected by fruit juices which stain, and cigarettes which burn, ordinary table linen. We have so far seen no record of lives saved by the use of glass sheets for those who insist on smoking in bed, but the possibility remains. Draperies of the material have made their appearance; and to mark the first birthday of the organization, a limited number of Fiberglas neckties, which look very well when tied, were distributed.

Fiberglas cloth has also entered the field of filtration. Its resistance to many of the fluids to be filtered makes it desirable; and to maintain the size of the pores the cloth is sintered.

All-Glass Pump.

Glass found another unique use in the form of an all-glass pump. Such equipment is particularly desirable in the chemical industry. It is resistant to nearly all corrosive chemicals; the transparent parts facilitate close inspection; and the pump is just as efficient as those made of other materials.

Shrunk Glass.

A new type of glass came on the market. Known as 'shrunk glass,' it is prepared by first dissolving out a large percentage by an acid treatment, after which the glass is subjected to a second heating, during which it shrinks to nearly half its first dimensions. The resulting ware is comparable to fused silica in its physical properties and offers a less expensive material for a great many industrial uses.

High-Test Safety Glass.

The new high-test safety glass has received much attention. It resulted from the cooperative effort of five large manufacturers and claims distinction because of the synthetic resin used in holding the two plates of glass together. This resin is highly elastic and retains a satisfactory degree of this elasticity even at low temperatures, something which has not been attained heretofore. This property greatly increases the safety factor at ordinary temperatures since the resin absorbs a considerable portion of the force of any blow and is essential for safety at low temperatures, because other resins become almost as brittle as glass when very cold and hence afford no protection whatever.

Glareless Glass.

Glass without glare is most welcome for store windows and other places where protection with non-reflection at the same time is desirable. At the beginning of 1939 two groups independently announced having found how to use very thin films to prevent reflection and thus render glass invisible. Very thin films are produced by depositing single layers of molecules, each layer with a thickness of about 0.0000001 inch until a thickness equivalent to one-quarter wave length of visible light has been built up. This means 42 molecular layers and the thickness is 0.000004 inch. During 1939 the technique of producing these very thin films was improved, but the process is not yet commercial and the films cannot be handled. So far, such layers of molecules have been used as gages for measuring thickness. To prevent the reflection of light by the glass, the film preferably has a refractive index value which is the square root of the refractive index of the glass.

Improvements in Gasoline.

Developments of new refining processes to increase the production of high-octane gasolines for military and commercial aviation were announced. Six plants in the United States now have an annual capacity of some 37,000,000 gallons, with other plants being planned or under consideration, making a total capacity of 125,000,000 gallons. The present consumption of aviation gasoline is about 20,000,000 gallons annually, but with the new processes in operation a potential productive capacity of 6,000,000,000 gallons of aviation gasoline is predicted. One of these new fuels is neohexane, produced under a pressure as high as 5,000 pounds to the square inch and at a temperature of about 950° F.

The growing use of tetracthyllead as an antiknock reagent led to a new plant at Baton Rouge, La., the second in the United States, and this is in process of substantial enlargement. During the year new cracking processes were announced. Greater flexibility is claimed for them, thereby making it possible to produce fuels or lubricants more nearly according to specifications, with somewhat higher yields than have heretofore been possible.

Advances in Metallurgy.

Some notable advances have been made in the field of metals and metallurgy. A process was developed for the use of low-grade manganese ores such as those available in Cuba, and the same process is useful with ores in the United States. We now import some 90 per cent of the manganese used in the manufacture of steel and a supply near home is essential. The new process makes importation much less important than it has been.

Tungsten ores were found in Coahuila, Mexico, and are refined at Eagle Pass, Texas. The Bureau of Mines, Department of the Interior, undertook an extensive investigation of domestic deposits of strategic minerals, following the outbreak of the European War. Minerals constitute the most important section of the remaining list of strategic materials, which from time to time is shortened through the application of the results of research.

A new alloy called Kennametal was introduced. It is composed of tungsten, titanium, and carbon and finds its principal application as a cutting tool. Several patents were issued as the result of research undertaken to improve the corrosion-resistance of stainless steel to sea water. Silver in small amounts is the added metal.

There have been advances in the use of carbon blocks for the lining of tanks and other equipment and for the formation of other pieces of equipment, either from this inert material or using it as a lining. Clad metals have made progress because they offer the advantage of the strength, weight, and low cost of some such material as steel, combined with the corrosion-resistance afforded by the relatively thin veneer of a suitable alloy which is an integral part of the unit. Thin sheets of stainless steel are now cemented by a special process to a mineral backing such as a thin section of concrete, producing what is called steel lumber. There is also a new form of filter, using, in place of filter cloths, piano wire properly spaced and held taut in but one direction.

Synthetic Vitamins.

The family of synthetic vitamins continued to grow. Vitamin K was the latest of these to emerge from the laboratories of American chemists. The first successful synthetic was reported in July, and now five forms of vitamin K have been synthesized. The material is valuable for its anti-hemorrhagic properties, though unfortunately it appears to be without effect in cases of hemophilia. The steady progress in the synthesis of members of the vitamin family is noteworthy when we remember how recently vitamins were little short of being an enigma. While their effects were known in some instances, their identity long remained obscure; and the research by which their structural formulas were established prior to synthesis, followed by the synthesis itself, affords examples of some of the best research that has been done in modern times.

Vitamin D has been produced from ergosterol of corn oil, and cholesterol of wool fat has been found to be a source of the same vitamin. A patent was issued on crystalline insulin. Gelatin was found to relieve fatigue and greatly increase energy.

Medicinal Agents.

The century has seen developed and introduced a number of amazing remedies and reagents for the use of the physician. Few, if any, have been so important as sulfanilamide and related compounds. Of these suleadyridine, found so efficacious in combating the many forms of pneumonia, including those for which there have been no serums, deserves special mention. Of the several hundred compounds that have been produced in the past three years, only a relatively small number have proved to be more effective than sulfanilamide, but the research goes on. It has been predicted that in the near future we may expect the discovery of the architectural designs of molecules which will be capable of annihilating all disease-causing bacteria. There are still lacking data enabling a satisfactory correlation between structure of the sulfanilamides and their effectiveness, but with the number of highly trained men active in this field and the results that have been obtained, there is reason to expect ultimate success.

During the year a new series of metathetical organic reactions produced catalytically was described. These approach perfection in efficiency because there is no loss through the formation of by-products or wastes which are ordinarily unavoidable in organic chemical reactions.

In the borderland between chemistry and medicine several important announcements were made. Certain sex hormones were synthesized, as was threonine, one of the proteins essential to life. Judging from the cost of the first synthesized material, it would cost $900 a pound to produce.

Management of Clinical Laboratories.

The year saw open discussion of the very important point as to whether clinical laboratories, the work of which is vital to the diagnostician, must be managed by members of the medical profession, with well-trained chemists declared to be ineligible for such service. The question is still highly controversial. But in the attempts to settle it a public service is being rendered because most of the tests now made to help determine a patient's condition and to indicate a program of treatment are carried out by technicians believed by many to be without that degree of chemical training which should be possessed by one undertaking work of such vital importance. Plans were perfected during the year for the improvement of conditions, largely by an effort to determine the exact training needed and how best to marshal available forces under really competent leadership to carry out this work.

Pulp and Paper.

Several important trends in the pulp and paper industry are to be noted. The steady improvement in the color of white sulfate, or bleached kraft as it is sometimes called, has brought its use into fine papers, replacing sulfite, more and more of which is going into esterification as in the manufacture of rayon. The expansion of kraft or the sulfate pulp papers in the South has been rapid and has created a growing demand for salt cake, formerly a by-product of the nitric acid industry when Chilean nitrate was treated with sulfuric acid to produce it. We now derive our nitric acid from the oxidation of synthetic ammonia. Much of our salt cake has been imported of late from Germany. But under conditions prevailing the latter part of 1939, it became possible to exploit natural resources of sodium sulfate, theretofore at a disadvantage because of freight rates; and the practice of recovering sodium sulfate from the viscose industry spread. The excess soda in the viscose sirup produces sodium sulfate in the acid setting bath and has now become an important source for this chemical compound. Meanwhile one of the alkali manufacturers perfected a method for making a synthetic salt cake from soda ash and sulphur. While this is not a true sodium sulfate, it is its equivalent in the sulfate pulp process.

Industrially speaking, it is well to know that the long-discussed paper mill at Lufkin, Texas, designed to produce newsprint from Southern woods, was put under construction with operations scheduled to begin late in 1939 or early in 1940. This comes at a time when much thought is being given to the pulp situation.

New Applications and Processes.

One of the gas companies operating in a great metropolis announced the chemical elaboration of water gas by-products and erected a plant for the production of a series of chemical compounds. One of the rubber companies seeking improved and less expensive methods for making molds in which tire casings and similar materials are cured, developed a new electroforming process for depositing iron and building up these molds to the desired pattern, weight, and strength. The process is applicable to much of the work in forming and casting art objects, including such fine detailed work as the reproduction of photographs.

A method has been perfected for the production of absorptive charcoal from pecan shells, and patents were issued during the year covering the manufacture of an absorptive type of charcoal suitable for gas masks. The effort, of course, is to free the United States from depending upon coconut shells as a raw material for that type of charcoal required in gas masks.

A development of growing interest is that of the use of dehydrated castor oil as a drying oil in paints and varnishes. The United States has used annually large quantities of Chinawood oil for this purpose. With the war in the Far East importation of sufficient quantities of tung oil has been difficult. The groves of tung trees, many thousands of acres in extent, in the South have begun to bear and the oil has been shipped in tank car lots. However, the total percentage available is small. Now comes the development of dehydrated castor oil, it having been found that when dehydrated a state of unsaturation is created and this oil becomes useful by itself or when mixed with tung oil in the paint and varnish industry. Most of the castor oil is imported from South America but the possibilities of establishing another crop in the United States are interesting, if indeed not bright. The castor bean plant is perennial in certain South American countries but so far as determined is an annual in the United States. This difference is considerable when interpreted in terms of costs.

Considerable advances have been made in the deodorization of vegetable oils.

Using vanillin, now made from waste sulfite liquor, a new chemical was prepared, trade-named Santo-mask, which when added to paints, varnishes, and enamels overcomes objectionable odor and irritating fumes. These are especially evident in interior painting; the new material neutralizes these odors, leaving no distinctive odor of its own.

A new chemical fire extinguisher uses gas under pressure to force easily decomposed solid sodium bicarbonate through a hose or pipe and a nozzle. Either one of two sources of pressure is used — liquid carbon dioxide in portable hand extinguishers, and compressed nitrogen in permanent installations. The bicarbonate is treated to prevent caking and to make it more easily decomposed by the fire. A stream of gas and powder is directed at the fire and the advantages include freedom from freezing, the avoidance of noxious fumes and water damage, and the permanence of the charge as compared with the ordinary acid-actuated extinguishers. The device can be used to replace water sprinkler systems.

Silicosis Preventive.

A discovery of importance was that a film of hydrated oxide of aluminum can be used to cover quartz particles and thereby prevent silicosis. If the aluminum powder is present to the extent of about one per cent by weight of quartz dust in the air, silicosis is completely prevented. In the lungs the aluminum forms a surface film which prevents toxic effects because the aluminum is insoluble.

Improvements in Curing of Tobacco.

Improvements in the curing of tobacco were announced. By using an air-conditioning system, so much time is saved that the capacity of the barns is doubled. And by determining the temperature and humidity conditions required for the best results, the art can be reduced to a science with a saving in labor and fuel; and limits beyond which the quality of tobacco deteriorates set up to prevent losses.

Foods.

There have been evolved improved and suitable dyes, as well as a method of application, for the coloring of oranges which, though ripe are pale in color, thus reducing consumer demand. Special dyes have in the past been produced and approved by the Food and Drug Administration as food colorers. These two, however, are the only new food colorers which have been admitted to the list for many years.

A new container for foods made its appearance in the form of a very thin rubber sack in which cuts of meat or whole quarters may be placed. Upon the application of vacuum this cover shrinks to an exact fit, thereby preventing evaporation, freezer burn, and other losses in the case of meats.

Another valuable process made its debut in 1939. Its purpose is to improve the grade of meat, and it is based upon maintaining a storage temperature that permits the growth of enzymes at the same time sterile conditions are maintained by the use of carbon dioxide and ultraviolet. The result is destruction or tendering of the connective tissue and a rise in the grade of the meat.

Other New Developments.

Development of the method for producing a thin flexible film of bentonite clay without binder proceeded with a view to producing a mica substitute applicable in some industries. An optical glass with the highest index of refraction and the lowest dispersion ever obtained was perfected during 1939. A new family of chemical compounds appeared in the nitroparaffins. These are produced by the nitration of some of the paraffin hydrocarbons and produce materials valuable as solvents, useful in the preventing as well as in the promotion of gelation, as in rubber latex and similar uses. It was also announced that natural gas could be nitrated, offering the possibility of certain kinds of explosives.

Silica aerogels made their commercial appearance and were offered as improved insulating materials, as bodying agents and antitacks of inks, lacquers, and varnishes, and to be used generally where bulk without material increase in weight is sought. Compounds to prevent the oxidation of soap and its rancidity or discoloration were also offered.

Cordura rayon, previously used in heavy tires for buses and trucks, was introduced in casings for passenger cars, offering new competition to cotton cords. A new process for black electroplating became available under the name of Moly-black. The deposited metal is composed of molybdenum and nickel. It is jet black, very hard, and has such throwing power that good plating is obtained even in deeply recessed places. Mysterious explosions of gasoline storage tanks in England gave rise to investigations; scientists reported that bacteria capable of fermenting kerosene into explosive gases were the probable cause.

Wetting agents found new applications in dentifrices, shampoos, and textile and laundering industries.

The experiment of growing melons with special alcoholic flavors, procured by introducing liqueurs and wine into their stems, was conducted successfully but to the disappointment of the grower, for while certain flavors were produced, there was no kick.

Organization Changes in the Industry.

The Dow Chemical Co. purchased the Great Western Electrochemical Co. The Bakelite Corp., pioneer in the field of synthetic resins, was merged with the Union Carbide & Carbon Corp. The International Agricultural Corp. announced the material expansion of its subsidiary, the Union Potash & Chemical Co., so that increased production of potash from American sources might go forward without delay. A new generator for the production of carbon dioxide in excess of 98 per cent purity as against the 30 to 35 per cent derived from ordinary kilns, was erected to produce the gas for dry ice. There were steady advances in pumps, high-pressure valves, automatic equipment for control of plants, recorders, and similar equipment. It is important to note that the four regional laboratories authorized for the Department of Agriculture for the purpose of promoting investigations of the non-food uses of agricultural products got under way so far as structure and organization of staff were concerned.

Progress in Chemicals since World War.

Twenty-five years ago there was much concern because imports of many technical and fine chemicals were stopped, and industry suffered from the ensuing shortage. It is a tribute to chemical progress in the United States that with war again raging in Europe we find a very different condition. The whole world was awakened to the value of applied science, particularly chemistry, by the World War; and the United States in particular began to develop chemical industry, with a view to making it more self-sufficient. The result is that in 1939 there were abundantly available dyes of the highest quality, many of them of American origin; medicinals and pharmaceuticals to meet the nation's requirements; satisfactory lines of synthetic perfumes and flavors; photographic chemicals; and other well-known products of the synthetic organic chemical industry. Within three months of Sept. 1, 108 technical and chemically pure chemicals previously imported were made in the United States to meet requirements; and in practically all instances whether or not such materials are regularly manufactured has been a question of economics, and not of scientific or technical knowledge.

Similarly in the last few years methods for recovering iodine from brines and bitterns occurring domestically have been perfected. Synthetic camphor has been produced in quantities adequate for all demands, with turpentine used as the raw material; not only has a technical grade been produced for the chemical industry, but a U.S.P. grade for pharmacy and medicine as well. A plant has been erected for the production on a large scale of urea of remarkable purity. This is important in fertilizers, as well as a raw material for the manufacture of one great class of resins, not to mention smaller quantities found useful in medicine. The curtailment of importations is also reflected in increased activity in the manufacture of potassium chlorate required particularly by the match industry and expansion of plants producing salts of potassium for agricultural purposes.

Honors and Awards.

Among the honors of the year in the field of chemistry, the following may be noted. The Nobel Prize was awarded to Adolph Butenandt of Berlin and Leopold Ruzicka of Zurich for their work on sex hormones, but under the laws of Germany Butenandt was unable to accept. The Perkin Medal for outstanding work in industrial chemistry in the United States was awarded to Walter S. Landis; the Schoellkopf Medal to C. F. Vaughn; the William H. Nichols Medal to J. H. Hildebrand; the Willard Gibbs Medal to D. D. Van Slyke; the Chemical Industry Medal to R. E. Wilson; the Borden Award to L. S. Palmer; the Eli Lilly and Company Award to George Wald; the Edward Goodrich Acheson Medal to Francis C. Frary; and the Herty Medal to Frank K. Cameron. The Standard Oil Development Corp, was given the Chemical and Metallurgical Engineering Award for achievement in chemical engineering. See also BIOLOGICAL CHEMISTRY; HORTICULTURE.