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Journal of the American Oil Chemists' Society | 1966

Polyester amides from linseed oil for protective coatings

L. E. Gast; Wilma J. Schneider; J. C. Cowan

The sodium alkoxide-catalyzed reaction of linseed oil or linseed methyl esters with diethanolamine produces almost exclusively linseed diethanolamides. Reaction conditions, e.g., temperature, amount of excess diethanolamine and mode of adding reactants, are reported. The best conditions for producing diethanolamide directly from linseed oil (1 mole) required adding oil to the sodium alkoxide in diethanolamine (6 moles) and heating at 110–115C for 35 min. The linseed diethanolamide isolated in 93–95% yield was an amber oil. Progress of the reaction, followed by thin-layer chromatography, showed only trace amounts of byproducts.Polyester amides were prepared by heating linseed diethanolamide in refluxing xylene with dibasic acids or anhydrides, e.g., azelaic, maleic, fumaric, phthalic, terephthalic, itaconic, brassylic and dimer acids. Molecular weight, viscosity and film properties (air-dried and baked) of the polyester amides were determined.


Journal of the American Oil Chemists' Society | 1977

Sperm oil replacements: Synthetic wax esters from selectively hydrogenated soybean and linseed oils

E. W. Bell; L. E. Gast; F. L. Thomas; R. E. Koos

Abstract and SummarySynthetic wax esters with properties similar to those of sperm whale oil have been prepared entirely from soybean and linseed oils. the synthesis required: (a) selective hydrogenation of the oils with copper-on-silica gel catalyst, (b) hydrogenolysis of fatty acids to fatty alcohols with copper-cadmiumchromium catalyst, and (c) esterification of hydrogenolysis products to yield predominantly long chain fatty esters which contained unsaturation in both the alcohol and acid moieties. Similarity of physical and chemical properties indicate that these wax esters are possible replacements for sperm oil. After sulfurization, the wax esters also have potential as extreme pressure lubricant additives.


Journal of the American Oil Chemists' Society | 1968

Polyesteramides from linseed oil for protective coatings low acid-value polymers

L. E. Gast; Wilma J. Schneider; J. C. Cowan

Linseed and soybean diethanolamides, from the sodium alkoxide-catalyzed reaction of the corresponding oil with diethanolamine, were used as diols to prepare a series of polyesteramides. The diols and dibasic acids or anhydrides were heated in refluxing xylene until the theoretical amount of water was collected in a trap. Low acid-value linseed polymers were prepared with 10, 20, and 30 mole percent excess diol over the dibasic acid, and the effect of the excess diol on molecular weight, viscosity, and film properties of the polymers was examined. Polyesteramides which contained 10 mole percent excess fatty diethanolamide were made with 11 dibasic acids or anhydrides. The polymers were brown-orange oils with Gardner viscosities of Z7 to >>Z10.Number-average molecular weights ranged from 2,200 to 5,200. Data on drying characteristics, hardness, and chemical resistance of films were obtained. The better polymers air-dried rapidly to give hard, glossy films (Sward rocker 20–60). Films baked at 190C for 10 min were softer than the corresponding air-dried films. Xylene resistance of soybean and linseed polymer films was generally excellent, and alkali resistance was moderate. Soybean films showed the better alkali resistance.


Journal of the American Oil Chemists' Society | 1969

Polyesteramides from linseed and soybean oils for protective coatings: Diisocyanate-modified polymers

L. E. Gast; Wilma J. Schneider; G. E. McManis; J. C. Cowan

New polymeric coating materials have been prepared by a triethylenediamine-catalyzed reaction of hydroxyl-terminated polyesteramides (HTPA) from soybean or linseed oils with diisocyanates. Eight dibasic acids or anhydrides were reacted with excess N,N-bis(2-hydroxyethyl) fatty amide to yield HTPA; those containing 10 mole per cent excess gave isocyanate-modified polymers with best overall film properties. Reactivity of four diisocyanates with a linseed-HTPA was measured by disappearance of the isocyanate band in the infrared. Depending on chemical composition, structure and curing conditions, films prepared from these polymers have a wide range of drying characteristics, hardness and chemical resistance. Drying times of linseed HTPA-urethane polymer films varied from 0.3 to 48 hr, hardness values (Sward) were from 4 to 70, alkali resistance ranged from 2 to 126 min and the hydrochloric acid and xylene resistances were good to excellent. Impact resistance exceeded 160 in.-lb for all films except two. The soybean-derived polymer films likewise exhibited a wide range of properties; they chiefly differed from linseed-derived films in having greater flexibility and improved alkali resistance.


Journal of the American Oil Chemists' Society | 1963

Composition of methyl esters from heat-bodied linseed oils

L. E. Gast; Wilma J. Schneider; C. A. Forest; J. C. Cowan

Two heat-bodied linseed oils, with Gardner viscosities of 37 and 55 min, were saponified, converted to their methyl esters, and separated into 2 fractions with urea and methanol. Gas-liquid chromatography showed the adduct fraction, which comprised 38–41% of the total methyl esters, to contain: palmitic, stearic, oleic, “linoleic,” and trace amounts of “linolenic” acid. The nonadducting fraction (59–62%) of the total methyl esters was separated by molecular distillation at 140C/7 μ into a distillate and residue. The distillate amounted to 18–25% of the total methyl esters and had an iodine value (I.V.) of 142–145; its absorption at 232 mμ indicates 2.5–3.0% conjugated diene. Hydrogenation of this distillate gave a liquid product with an iodine number of 4 and a pour point of −50C. Gas chromatograms of the distillate and its hydrogenated derivative indicated at least 5–7 components. Comparison of these peaks with known fatty acid methyl esters indicates that the components of these fractions were either cyclic or branched esters. The nonadducting residue fraction was composed mainly of polymeric acids.


Journal of the American Oil Chemists' Society | 1964

A convenient laboratory method for preparingtrans, trans-9, 11-octadecadienoic acid

Wilma J. Schneider; L. E. Gast; H. M. Teeter

A convenient laboratory method to preparetrans,trans- 9,11-octadecadienoic acid (TTA) via a polyester intermediate is described. Ricinelaidic acid was heated at 235C under vacuum for 3-4 hr to form a polyester having a mol wt of 1,500-1,600. Pyrolysis of this polyester and simultane-ous distillation of the products gave crude dehy-drated acids. TTA was crystallized from a 95% ethanol solution of these acids, in a yield of 35%. Of the variables affecting pyrolysis, the mol wt of polyester had the greatest effect on yield of TTA.


Journal of the American Oil Chemists' Society | 1960

Reactions of unsaturated fatty alcohols. VII. Polymerization of vinyl ethers catalyzed by stannic and ferric chlorides

E. J. Dufek; R. A. Awl; L. E. Gast; J. C. Cowan; H. M. Teeter

SummaryVariables affecting the use of stannic chloride as a catalyst for initiating polymerization of conjugated and nonconjugated soybean vinyl ether were studied. Molecular weight of the polymers increased with an increase in catalyst and a decrease in initiation temperature, and it decreased when the amount of moisture in the solvent, the amount of free fatty alcohol in the monomer, or the ratio of solvent to monomer was increased. Aromatic and aliphatic hydrocarbon solvents were superior to halogenated solvents for conducting polymerizations. Similar results were obtained with nonconjugated monomers except that viscosities of the polymers were considerably lower than those of polymers of the same molecular weight obtained from conjugated monomer.To obtain polymers suitable for film-forming studies (4,000–6,000 molecular weight) polymerization is initiated preferably at 25°C. with 3 ml. of anhydrous toluene used per gram of monomer and 4.8 mmoles of stannic chloride per mole of monomer. Monomer purity should be at least 98%.Ferric chloride hexahydrate initiated polymerization at 25°, but polymerization was incomplete, and the polymers had relatively low molecular weights.


Journal of the American Oil Chemists' Society | 1968

Free radical addition of hydrogen sulfide and thiols to linseed oil and methyl oleate

A. W. Schwab; L. E. Gast; J. C. Cowan

Free radical additions of hydrogen sulfide, ethanedithiol, and 1,6-hexanedithiol have been made to methyl oleate and linseed oil with ultraviolet radiation. Reactions were carried out in dichloromethane at −70C and in benzene at 25C. With the dithiols, a new dibasic ester has been prepared from methyl oleate in which bridging is accomplished through a dithiol moiety. Hydrogen sulfide has been added to linseed oil in suitable solvents at both −70C and 25C. It appears that zero-order kinetics control the additions at both temperatures. Infrared data show a linear relationship between mercapto absorption and the amount of sulfur incorporated. Nuclear magnetic resonance (NMR) spectra demonstrate a decrease in olefinic protons with an increase in sulfur content. Fair agreement on the extent of reaction exists between data from NMR, sulfur content, and infrared analyses. Hydrogen sulfide-treated linseed oil films air-dry slowly at room temperature; at 250C for 1 hr under a CO2 atmosphere these oils cure to brown films with Sward Rocker values of 24 to 32 and pencil hardness values of five to greater than six. Pencil hardness and alkali resistance increased with sulfur content. The film from the 4.2% sulfur sample resisted alkali at room temperature for 24 hr.


Journal of the American Oil Chemists' Society | 1973

Hydrogen Sulfide Adducts of Methyl Oleate and Linoleate

A. W. Schwab; W. K. Rohwedder; L. W. Tjarks; L. E. Gast

Sulfur compounds derived from photochemical addition of hydrogen sulfide to methyl oleate and linoleate were separated by preparative gas chromatography. The major compounds were investigated by NMR, mass and IR spectroscopy and by elemental analysis. The primary product of the methyl oleate reaction was methyl 9(10)-mercaptostearate. Gas chromatograms of the product from methyl linoleate showed four principal peaks. From mass spectra and NMR data, we identified methyl 9-(2-pentyl-1-thiolan-5-yl)nonanoate, methyl 8-(2-hexyl-1-thiolan-5-yl)octanoate and methyl 9-(3-hexyl-1,2-dithiolan-5-yl)nonanoate. Evidence for the formation of methyl mercapto-octadecenoates and methyl dimercaptostearates was also obtained.


Journal of the American Oil Chemists' Society | 1958

Reactions of unsaturated fatty alcohols. V. Preparation and properties of some copolymers of unsaturated fatty vinyl ethers with lower alkyl vinyl ethers

L. E. Gast; Wilma J. Schneider; J. L. O’Donnell; J. C. Cowan; H. M. Teeter

SummarySoybean vinyl ethers derived from soybean alcohols were copolymerized with lower alkyl vinyl ethers,e.g., ethyl, butyl, isobutyl, 2-chloroethyl, 2-methoxyethyl, and 2-ethylhexyl, in methylene chloride at −30°C., using boron trifluoride etherate catalyst. Molecular weights ranging from 2,000 to 4,000 were obtained on these copolymers by cryoscopic measurements in cyclohexane. An analytical method, using infrared spectroscopy, was employed to determine the composition of the copolymers.The properties of each alkyl-soybean vinyl ether copolymer were studied at three molar compositions,e.g., 3∶1, 1∶1, and 1∶3. The products were water-white to amber viscous liquids and were soluble in aromatic, chlorinated, and gasoline type of solvents.Copolymers films were prepared under conditions that were shown to produce extensive degradation of some homopolymer films in order to magnify small differences in properties. These films were hard, wrinkle-free, and resistant to most common solvents, also were 20 to 500 times more resistant to 5% aqueous alkali than soybean vinyl ether polymer prepared under the same conditions.Copolymer films were baked on silver chloride plates and examined in the infrared. Oxidative degradation of the C−O−C ether linkage was observed in all copolymer films; however the 2-chloroethyl-soybean copolymer series was least susceptible to this degradation.

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J. C. Cowan

United States Department of Agriculture

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H. M. Teeter

United States Department of Agriculture

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Wilma J. Schneider

United States Department of Agriculture

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A. W. Schwab

United States Department of Agriculture

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E. W. Bell

United States Department of Agriculture

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W. K. Rohwedder

United States Department of Agriculture

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E. J. Dufek

United States Department of Agriculture

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J. L. O’Donnell

United States Department of Agriculture

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John L. ODonnell

United States Department of Agriculture

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R. E. Koos

United States Department of Agriculture

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