CHEMICALS FROM FATS AND OILS The cheapest commercially available source of nitrogen is ammonia, and the primary reaction product of ammonia with fatty acid is, of course, the ammonium soap. Subjected to heat, this intermediate will lose a mole of water to form the long-chain unsubstituted alkyl amide. These have been used as antiblocking agents, as wax additives, as antitacking agents, as water-repellents, and as suds stabilizers. Reaction with formaldehyde gives the methylol derivative or the methylene bis diamide, useful for many of the same things as the amide, but more so as a wax substitute per se. In the cosmetic industry, they are excellent detergent and foam boosters and stabilizers for soaps and synthetic detergents. They are quite compat- ible with them and act, in addition, as thickening and clarifying agents. Stearamide, which is soluble in mineral oil, is an additive in some hair creams, helps stabilize cosmetic emulsions, and eases re-emulsification if drying out has occurred. The amides operate best in o/w emulsions, but in the presence of traces of fatty acid will reverse and give good w/o emulsions. The amides function also, it is claimed, as hydrolysis retarders for aluminum-chloride-containing products a decrease in undesirable acidic by-products will result. And, finally, the alkyl amides have been found to be better solubilizers for indelible lipstick dyes than castor oil, tetrahydrofurfuryl alcohol, or butyl stearate. The N-substituted amides, from fatty acids and ethanolamine or diethanolamine for example, have certain additional functions in cosmetic preparations. The ethanolamide of stearic acid acts as a pearly opacifier in liquid cream shampoos. It is a strong, acid-stable, self-emulsifier and a corrosion inhibitor. The di- ethanolamides are emulsifiers and viscosity increasers in shampoos, help dispel calcium soap sludges, and are foam stabilizers and hair conditioners. The unsubstituted amides, upon further subjection to high temperature, over a catalyst, lose another mole of water to give the nitriles. These have been used as plasticizers, water repellents, and lubricants, but their main function is as intermediates in amine preparation. Catalytic reduction of the nitriles will, depending upon reaction condi- tions, give the primary or the symmetrical secondary amine, a versatile se- ries of compounds in terms of application or as intermediates in further chemical synthesis. The primary amines, or their organic or inorganic salts are very valuable flotation agents, the first large, successful, develop- mental use for these compounds and still a big outlet for the amines. They have seen use, too, as emulsifying agents, insecticides, rubber vulcanizing agents, etc. The secondary amines are valuable mainly as intermediates in quaternary ammonium salt formation, but uses, per se, are developing. Their organic or inorganic salts, in addition, have the interesting property of hydrocarbon solubility, which opens up additional avenues of approach from a use standpoint. Chemically, the amines undergo a varied and valuable series of teac-

94 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS tions. They will, for example, react with acrylonitrile. This, upon cata- lytic hydrogenation gives what we call a Duomeen, a versatile dibasic amine containing a primary and secondary amine grouping. As such, or in the form of its salts, these compounds are finding wide use as asphalt additives, corrosion inhibitors, oil recovery agents, etc. The amines can be reacted, too, to give the amino burytic acid derivative, a zwitterion type of compound capable of forming inner salts and of reacting with acid or base that is, it contains an amino and a carboxyl group in the same molecule. As the sodium salt, this compound has interesting emulsification and de- tergency properties. The amines will also react with phosgene to give the isocyanates, useful as toxicants with metallic salts, such as silver, mercury, or copper chloride, to give the corresponding amine complexes and double salts, used as mold inhibitors and rubber accelerators with formic acid and formaldehyde to give the dimethyl tertiary amines, in- termediates in quaternary formation with thiourea hydrochloride to give the guanidine derivative, a rubber accelerator and with carbon disul- fide to give thioureas and dithiocarbamates. All of these, and more, are practical compounds, all preparable and all in or beyond the develop- mental stage. Alkylation of the amines, with methyl chloride for example, gives the corresponding quaternary ammonium compounds, which completes the picture of the basic nitrogen containing fatty acid derivatives. These compounds have been and are being extensively investigated. They are, of course, potent germicides, excellent cationic emulsifiers for w/o emulsion, and, in the case of those derived from the secondary amines, are hydro- carbon soluble. They have found outlets in the antibiotic field, as corro- sion inhibitors, as bactericides, as antistatic agents, as cloth softeners, and as grease substitutes. They are, of course, incompatible with the an- ionics, soaps, and with some proteinaceous material, and their function as active components in cosmetic preparations is necessarily limited. They are excellent hair conditioners and softeners, as after-rinses of course, to avoid inactivation by soaps. Perhaps the Duomeen diquaternary will function more effectively here. Again, quaternaries, if compatible, may perhaps replace aromatics as preservative agents in some cosmetic prepa- rations perhaps, too, they would have some deodorant action, because of their bactericidal activity. They have been tried, also, as antidandruff agents a 4 per cent solution of Arquad 18 applied to the hair a few minutes before rinsing has shown evidence of success. And, finally, they have been incorporated in permanent waving solutions and give a desir- able opaqueness here too. The last class of derivatives that I should like to mention is the non- ionics, the condensation products of ethylene oxide and active hydrogen, specifically the acids, amines, and amides. These are becoming very prom-