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.