INTERNATIONAL CONGRESS ited to hydrolysis culminating either in a Claisen type condensation or hydrogen bonding of the polyacrylic acid. Side group and main chain spacings of the various esters of polyacrylic acid and ganirna-carboxpimelic acid, ranging from methyl to 2-ethylhexyl, were made by x-ray. The side group spacing progresses uniformly from 7.6 A. for methyl aery late to 12.4 A. for η-butyl. The binding in the acids was found much stronger than in the esters examined. Hydrolysis of t h e methyl acrylate leads to an increase in side group spacings. Polyacrylic acid shows a marked change in structure when plasticized with water or alcohol, the hard, brittle acid be coming rubbery. X-ray pattern indicates that the strong hydrogen binding between side chains has been broken up by asso ciation with water or alcohol. Vulcaniza tion of polymethylacrylate showed an in terchain spacing increase and plasticization with methanol of a methyl acrylateacrylic acid copolymer produced an in creased spacing. This indicates that the vulcanization proceeds by controlled hy drolysis followed by hydrogen bonding. Such a mechanism should be sensitive to moisture, it was stated, in agreement with the fact that anhydrous sodium silicate will not affect vulcanization and the fact that cured polymers are affected by moist heat. Fresh Latex Solutions. G. F . Bloomfield, British Rubber Producers Research Association, England, offered a report on the production of solutions of rubber hy drocarbon in the latex of Hevea brasiliensis by allowing latex to flow from the tree directly into benzene or into a vistex solvent mixture. The hydrocarbons in such solutions were of high molecular weight, according to Dr. Bloomfield, with a broad distribution from several million to below 100,000. The major portion is in the higher range. Differences in molecular weight were found among the products of different trees and single trees varied over a period of time, according to Dr. Bloomfield, but no correlation w a s found between changes in molecular weight and periods of bio logical activity such as refoliation. In de termining the effect of stnicture, particu larly cross-linking, plasticity determina tions proved more satisfactory than in trinsic viscosity measurements. Microgel structure was indicated by hardness, the proportion being greater in the harder rubbers. By observing the proportion of microgel it was possible to define the area of a tree affected by tapping and this in dicated that tapping affected the latex over a greater area in a high yielding tree than in a low yielding one. It was ob served that when two tapping cuts are opened in the same tree, the latex drawn from the higher cut gives a much harder rubber than that from the lower. Also there was found more phosphorus and potassium and less magnesium in the lower cut latex.
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Low Temperature Linseed Oil Oxida tion. A novel method for the low tem perature oxidation of linseed oil up to the viscous oil stage was presented by F. T. Walker and T. Mackay, Michael Nairn and Co., Scotland. This, it was stated, combines advantages of both the scrim and mechanical processes and gives an appreciable increase in the rate of oxida tion. A packed column is used and the oil is fed in at the top while warm air is fed in at the foot, passing countercurrent to the oil flow. This provides exposure of a great deal of film surface and a rapid oxidation to a bodied oil. Further treat ment is needed to get a gelled product. Emulsion-Free Aqueous Polymerization. G. S. Whitby, M. D. Gross, J. R. Miller, and A. J. Gostanza, University of Akron, described studies of polymerizations in aqueous media in which no emulsifier was included. A variety of experiments in cluded the study of redox polymerization in water, without emulsifier, of a water-
soluble and a water-insoluble monomer. Copolymerization proceeded at a reason able rate and frequently formed a stable latex. Styrene and 5 or 1 0 % methacrylonitrile in water with a water-soluble persulfate-bisulfite redox pair was examined in detail: it was found that the rate of polymerization increased with the propor tion o f water-soluble monomer. Polymeri zation is initiated in the aqueous phase, it was reported, as it was shown that water-soluble retarders are more effective than oil-soluble, when added at the out set, b u t oil-soluble retarders are more ef fective at a stage where the free monomer has all entered into polymerization. Con trary to the action in an emulsion poly merization, it was observed, the watersoluble monomer enters into the polymer at a greater rate than does the waterinsoluble monomer; but even at the earliest stages at which it was practical to take samples, copolymerization had occurred.
FATS A N D FATTY OILS, SOAPS, AND OTHER DETERGENTS
Fatty Acids Separated by Rubber Chromatography • Progress noted in identifying fatty acids in animal and vegetable fats and oils p y
RUBBER
chromatography
it is pos-
•*-' sible not only to separate saturated fatty acids in the C e to C24 range, but also to separate various C» acids including stearic, oleic, and linoleic, according to 11. A. Boekenoogen, Unilever Research Laboratory, Holland, who spoke at the opening session of the Section on Fats and Fatty Oils, Soaps, and Other Deter gents. Interference between saturated and un saturated acids is the principal limitation encountered in separating a mixture of fatty acids such as is found in a normal fat or oil. Because of the high ratio of rubber to fat ( 1 0 0 0 : 1 ) , the method is not practical for separating large amounts of material. Original chromatographic methods and partition chromatography using hydrophilic sorbents such as silica in the im mobile phase and less polar solvents in the mobile stage were not satisfactory for separating lipides. Dr. Boekenoogen de veloped a carrier composed of partially vulcanized rubber ground to a powder (particles 1 / 2 to 1 mm. in diameter) which can absorb nonpolar solvents to overcome this difficulty. His method not only separates fatty acids from triglycerides but also separates partial glycerides. In this liquid-liquid ex traction, the rubber may be considered as a solid liquid. In analyzing a fat, an ini-
CHEMICAL
tial separation is made to take out the saturated fatty acids and the amounts of each are determined. By then hydrogenating a sample of the original product, effecting a separation by rubber chroma tography, and determining the amounts of each present, the percentage of unsaturated constituents can be calculated.
^ Fatty A c i d Separation An entirely different approach to the separation of fatty acids -was reported by E. Marshall Meade, University of Man chester, England, w h o stated that urea can form stable complexes with long straight-chain compounds, including hydro carbons containing u p to 16 carbon atoms, fatty alcohols, and fatty acids. This property can be used to effect fairly complete separation of fatty acids of differing degrees of saturation and may be used to separate straight chains from branched chain compounds since the latter do not form stable complexes. Specific applications of this principle may be made in the case of such tonnage products as sperm oil and commercial butyl acetyl ricinoleate, a plasticizer. L. H . Dunlap, Armstrong Cork, con firmed the fact that formation of urea adducts of fatty acids allows partial sepa ration of the acids. More specifically, he noted, the separation follows predictable
AND ENGINEERING
NEWS
FATS AND FATTY OILS, SOAPS, A N D OTHER DETERGENTS
S. E . Wiberley, Rensselaer Polytechnic Institute, demonstrates his infrared absorption spectra equipment ratios, the ratios being more favorable for separating the saturated than the unsaturated acids. New Bacterial Compounds. N e w crystalline quaternary ammonium salts have been prepared from triethanolamine ethers, reported H. K. Sturm, Friedrich Steinfels, AG, Zurich, Switzerland. These compounds, in addition to showing potential uses as textile finishing agents, have very notable bactericidal properties and little toxicity. Dr. Sturm noted, for example, that most bacteria are killed within t w o minutes at dilutions of 1:1000. He feels that these salts show promise as surgical sterilizing agents and in the manufacture of disinfecting soaps. Diet-Essential Fats. Female rats, when raised and kept on a fat-deficient diet, do not reproduce or lactate normally, F. A. Kummerow, University of Illinois, reported. Total fat analysis, however, indicates that these animals are not deficient in fat per se, but in arachidonic acid. H e concluded that this acid is not synthesized in sufficient quantities in the body unless dietary sources of linoleic acid are available.
• Identification of Fatty Acids Progress in determining the composition of sperm oil by use of selective adsorption ( chromatography ) , fractional distillation, and ultraviolet absorption studies was reported by H. A. Schuette, University of Wisconsin. Sperm oil, h e stated, is known to consist of a complex mixture of high molecular weight saturated and unsaturated aliphatic alcohols, some hydrocarbons and other constituents. Among the components he has identified recently are squalene, cholesterol, and several polyunsaturated alcohols containing a 1:4 double bond system.
VOLUME
Aluminum mono and di soaps are distinct chemical compounds, according to infrared absorption spectra studies by Stephen E. Wiberley, Rensselaer Polytechnic Institute. The mono soaps have bonded hydroxyl groups, a n d the di soaps free hydroxyl groups. Tri soaps do not exist, the so-called tri soaps consisting of di soaps plus loosely combined fatty acids. In attempts to develop theories of fatty acid formation, C. Y. Hopkins, National Research Council, Ottawa, O n t , has studied one o f the least known common fatty acids, ?i-eicoseenoic acid, C20H38O2. Of several fish and vegetable oils studied, only jojoba oil contains any substantial amount of this acid. He h a s noted this oil is unsaturated in the 11:12 position. Soiling Fibers. Soil particles deposit preferentially on other particles rather than by uniform deposition at all points, according to studies on white cotton fabrics by Irving Reich, Foster D. Snell, Inc. This suggests that for these cloths removal of soil was mainly by detachment of complete aggregates rather than by re' versai of the original flocculation process. Tall Oil Uses. Tall oil, a mixture of fatty and rosin acids and higher alcohols, is finding increasing acceptance in industry and is being used in the manufacture of paints a n d varnishes, soaps and sanitizing chemicals, and in castings (as a core oil), reported C. B. F. Young, National Southern Products. Trîis acceptance is due not only to desirable quality but to plentiful supplies at stable prices. Soap Viscosities. The linear reduction of viscosity o f aqueous polysoap solutions on addition o f hydrocarbon indicates that these soap molecule coils are contracted by the solubilizate, according to Ulrich P. Strauss, Rutgers University. When the solubility limit of the hydrocarbon is reached, further hydrocarbon addition does not further reduce viscosity. These results agree with vapor pressure method observations. This phenomenon therefore furnishes a n e w method for measuring solubilization of hydrocarbons by poly soaps. Fat Recovery. The expense and incomplete recovery in the solvent extraction method, a n d the inefficiency of superheated steam in recovering fat in filter press decoloring agents, l e d A. Vassilievsky, Montgeron, S. O., France, to develop an autoclave method. He reported that by using a sodium chloride-sodium carbonate electrolyte i n an autoclave operating at three to five atmospheres, he effected complete recovery. In Dr. Vassilievsky's absence Miss P . R. E. Lewkowitsch of London translated and presented an abstract of the report. Foams. Important physical properties of foams s u c h as drainage rates and ultimate solubilities are determined largely by the nature a n d amount of surface active material concentrated in the film surfaces. In order t o obtain such data, Cheves Walling, Lever Bros., has developed a relatively simple apparatus by which he
2 9, N O . 3 9 » S E P T E M B E R
2 4, 1 9 5 1
can collect determined amounts of foam and measure directly the foam stability. Rosin Acid Determination. J. M. Vizern, Vizern and Guillot Laboratory, Marseilles, France, reported that laboratory experiments comparing the sulfuric acid catalyst method of determining rosin acid content of soaps with the naphthalene-j3-sulfonic acid catalyst method (McNicoll method) proves that both give equally accurate results. In both methods, a corrective factor compensating for the incomplete esterification of the fatty acid is necessary as well as the assigning of an arbitrary mean value for the molecular weight of rosin acids. Equilibrium Studies. An exponential formula relating the solubilities of some polar organic compounds such as primary alcohols and methyl ketones in waterglyceride solutions has been developed by B. A. Lindenberg, Paris, France, according to his paper, translated and presented by Miss P. R. E. Lewkowitsch of London. French Technical Publications. To make more readily available the postwar scientific research and technical documents of French scientists and technicians working in official, private, and industrial laboratories, the French fat industry established the Federation Nationale d e l'Industrie des Corps Gras. G. Wolff, Paris, France, reported the creation of two technical institutes: t h e Institut de Recherche des Huiles de Palm et Oleagineaux ( I R H O ) , which is concerned primarily with tropical oil crops, and the Institut de Corps Gras, established in 1943 to improve methods used in t h e French fat industry. IRHO published a monthly scientific and technical review, Oleagineaux, in collaboration with ITERG. ITERG also publishes a private review of French and foreign technical developments, v/hich is circulated to federation members. H . A. Boekenoogen, Unilever Research Laboratory, Holland, explains details of his rubber chromatography separation
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