C18-saturated cyclic acids from linseed oil: A structural study

The preparation of C₁₈-saturated cyclic acids from linseed oil by heat treatment in the presence of alkali, followed by hydrogenation and subsequent isolation of the cyclic fraction, gives rise to a series of at least 11 isomers as evidenced by GLC. Eight of these isomers have now been shown to be geometric pairs of positional isomers with the following general formula: {fx244-1} An unequivocal synthesis of isomers (x=0,1,2 and 3) indicates that the principal positional isomer (ca. 55%) of HCal is 9-(2′-n-propylcyclohexyl)-nonanoic acid. This isomer undoubtedly results from the cyclization of 10,12,14-octadecatrienoic acid present in the isomerized mixture. The predominance of this isomer is further substantiated by mass spectral analysis. The four positional isomers prepared constitute about 80% of the mixture as determined by gas-liquid chromatography. The four synthetic aromatic positional isomers show single peaks whereas their hydrogenated counterparts show two peaks. Thus each of the positional isomers of saturated cyclic acids is composed of two geometric isomers.     

Emulsifiers derived from linseed oil and their potential use in coatings

In the development of a stable linseed oil emulsion paint, a series of emulsifiers were prepared from linseed, oil and its fatty acids and alcohols: (a) linseed monoglycerides, (b) mono-and dilinseed fatty sorbitan esters and a mixed ester obtained by the transesterification of linseed oil with sorbitol, (c) polyoxyethylene ether adducts formed by reacting, ethylene oxide with these sorbitan esters, and (d) linseed polyoxyethylene ether made by ethoxylation of linseed alcohols. Another series of surfactants was prepared by esterifying a polyoxyethylene ether of sorbitol with various amounts of linseed fatty acids. Conditions of preparation and pertinent physical, and chemical properties of the emulsifiers are given. Some of these emulsifiers demonstrated filmforming properties. Combinations were formulated into linseed oil emulsion paints with and without zinc oxide. Paints containing zinc oxide have been relatively stable in viscosity for about 2 yr.     

Polyunsaturated fatty acid concentrates from borage and linseed oil fatty acids

A modified low-temperature solvent crystallization process was employed for the enrichment of polyunsaturated fatty acids (PUFA) in borage and linseed oil fatty acids. The effects of solvent, operation temperature, and solvent to free fatty acid (FFA) ratio on the concentration of PUFA were investigated. The best results were achieved when a mixture of 30% acetonitrile and 70% acetone was used as the solvent. With an operation temperature of −80°C and a solvent to FFA ratio of 30 mL/g, γ-linolenic acid (GLA) in FFA of saponified borage oil can be raised from 23.4 to 88.9% with a yield of 62.0%. At a yield of 24.9%, α-linolenic acid in linseed oil can be increased from 55.0 to 85.7%. The results of this work are comparable to the best results available in the literature.     

Production of linolenic acid from linseed oil

Linolenic acid of more than 95% purity was produced by liquid-liquid extraction of linseed oil fatty acids with wet furfural and hexane in a Podbielniak centrifugal extractor. The minimum ratio of furfural to linseed acids to obtain this purity was 10 to 1. There was no significant change in product purity for solvent ratios between 10 and 15, operating temperatures from 90° to 110°F., and furfural moisture contents between 1.0 and 2.8%. When the solvent ratio is reduced to 8 or the furfural moisture to 0.2%, purity decreases. Oxidation of linseed acids before extraction also results in decreased separation. An estimate based on pilotplant data indicates a “cost to make” (excluding administrative and selling expenses, profit, income taxes, and interest on investment) of 18.0 cents per pound of 97% linolenic acid for a process which includes hydrolyzing linseed oil, separating the fatty acids by liquid-liquid extraction, recovering solvents by distillation, and distilling the fatty acid products. Potential uses for linolenic acid are reviewed.     

Cyclic fatty acid yields from linseed oil

Increased yields of saturated cyclic fatty acids which are fluid at −50C have been obtained from linseed oil. Depending on reaction conditions, yields varied from 20–42 g of cyclic acids per 100 g of linseed oil. Solvent ratios of 6, 3, and 1.5∶1; catalyst concentrations of 10, 30, 60, and 100%; and reaction temps of 225, 275, 295, and 325C were evaluated. Ethylene glycol and diethylene glycol were compared as reaction solvents. In general, high solvent ratios favored high cyclic acid yields at the lower reaction temperature, but as the temperature increased the effect of solvent ratio decreased. Increasing the percentage excess of sodium hydroxide increased the cyclic acid yield. Diethylene glycol gave higher yields than ethylene glycol at comparable conditions. Presented at the AOCS meeting in Chicago, Ill., October, 1961. A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.     

Amide plasticizers from safflower and tall oil derived fatty acids

Fatty acids derived from a high oleic strain of safflower seeds are eminently suited for the preparation of compatible and efficient N,N-disubstituted fatty acid amide polyvinyl chloride plasticizers with low temperature properties in the adipate-azelate range. N,N-disubstituted amides of tall oil-derived acids, Westvaco Type 1480, give comparable plasticizing performance. Polyvinyl chloride compositions plasticized with the hexachlorocyclopentadiene adduct of N,N-dibutyloleamide show no soapy water extraction loss. So. Market. Nutr. Res. Div., ARS, USDA.     

Levels of polyunsaturated fatty acids in tissues from zinc-deficient rats fed a linseed oil diet

The effect of zinc deficiency on the levels of n−6 and n−3 polyunsaturated fatty acids (PUFA) in lipids from tissues of rats fed a diet containing linseed oil was investigated. Rats were fed either a control diet (25 mg Zn/kg) or a zinc-deficient diet (0.8 mg Zn/kg) for 10 d. To avoid energy and nutrient deficiency, 11.6 g of diet per day was administered by gastric tube. At the end of the experiment, rats fed the zinc-deficient diet had drastically reduced plasma zinc concentration and alkaline phosphatase activity consistent with severe zinc deficiency in these rats. Zinc-deficient rats had higher levels of n−3 PUFA, in particular eicosapentaenoic acid (EPA), and lower levels of n−6 PUFA, in particular linoleic acid, in liver and plasma phosphatidylcholine (PC) and in erythrocyte membrane total lipids than did control rats. By contrast, the levels of n−3 PUFA in PC from testes and heart, and in phosphatidylethanolamine (PE) from liver, testes and heart, were only slightly different between zinc-deficient and control rats. The study suggests that desaturation of α-linolenic acid is not inhibited by zinc deficiency, and that in zinc-deficient rats, n−3 PUFA preferentially incorporated into phospholipids at the expense of n−6 PUFA, especially EPA into PC. The study also shows that the effect of zinc deficiency on PUFA levels is different for PC and PE in rat tissues.     

Polyester amides from linseed oil for protective coatings

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. Presented at the AOCS Meeting, Chicago, October 1964. No. Utiliz. Res. Dev. Div., ARS, USDA.     

Super acid catalyzed dimerization of fatty acids derived from safflower oil and dehydrated castor oil

Dimerization of fatty acids derived from dehydrated castor oil and safflower oil was carried out on the recently described sulphate-treated zirconia catalyst and trifluoromethane sulphonic acid (triflic acid) under autogeneous pressure in the temperature range of 160–240 C. Triflic acid was observed to be highly active; however, the product obtained was deeply colored. Zirconia exhibited high activity for the reaction. The important features of this catalyst were the high selectivity for dimer (low yields of trimer) and no significant coloration of the products. The zirconia catalyst shows promise for industrial use.     

PMMA‐multigraft copolymers derived from linseed oil,soybean oil,and linoleic acid: Protein adsorption and bacterial adherence

Synthesis of Poly(methyl methacrylate), PMMA‐multigraft copolymers derived from linseed oil, soybean oil, and linoleic acid PMMA‐g‐polymeric oil/oily acid‐g‐poly(3‐hydroxy alkanoate) (PHA), and their protein adsorption and bacterial adherence have been described. Polymeric oil/oily acid peroxides [polymeric soybean oil peroxide (PSB), polymeric linseed oil peroxide (PLO), and polymeric linoleic acid peroxide (PLina)] initiated the copolymerization of MMA and unsaturated PHA‐soya to yield PMMA–PLO–PHA, PMMA–PSB–PHA, and PMMA–PLina–PHA multigraft copolymers. PMMA–PLina–PHA multigraft copolymers were completely soluble while PMMA–PSB–PHA and PMMA–PLO–PHA multigraft copolymers were partially crosslinked. Crosslinked parts of the PLO‐ and PSB‐multigraft copolymers were isolated by the sol gel analysis and characterized by swelling measurements in CHCl₃. Soluble part of the PLO‐ and PSB‐multigraft copolymers and completely soluble PLina‐multigraft copolymers were obtained and characterized by spectroscopic, thermal, gel permeation chromatography (GPC), and scanning electron microscopy (SEM) techniques. In the mechanical properties of the PHA–PLina–PMMA, the elongation at break is reduced up to ～ 9%, more or less preserving the high stress values at its break point (48%) when compared to PLina‐g‐PMMA. The solvent casting film surfaces were studied by means of adsorption of blood proteins and bacterial adhesion. Insertion of the PHA into the multigraft copolymers caused the dramatic increase in bacterial adhesion on the polymer surfaces. PHA insertion into the graft copolymers also increased the protein adsorption. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Functional analysis of gas chromatographic data for C-4 through C-18:2 fatty acids

The problem of finding a functional relationship between concentration and output data from GC has been considered for a series of fatty acids (FA). The concentrations used are relative values, i.e., the actual concentration of a FA divided by that for an internal standard. The GC output used is relative peak areas, i.e., the integrated chromatogram area of the FA divided by that for the internal standard. Five functions have been investigated, each in reasonable accord with the concept of relative response factors being constant for a homologous series of compounds. We conclude that one of the five, C_j = aA _j ^b , is clearly superior and recommend its use in agreement with a literature report for different compound types (5). In the equation above, “C” and “A” are the relative concentrations and areas, respectively, and “a” and “b” are fitting constants determined from the data by least-squares minimization. We found it was impossible to deal with a matrix of 10 acids and 9 concentrations in a manner that would reproduce the data within the experimental uncertainty (6%), and we concluded that an acid-by-acid analysis was preferable.     

Dilution polymerization of linseed oil

Summary An inert diluent, molecularly distilled mineral oil, when present in 90% concentration, permitted, in linseed oil, the polymerization of acyl groups in the absence of inter-glyceride reaction. Comparison of the data for the polymerization of linseed oil in 10, 20, and 100% concentrations showed a marked concentration dependence for the following: polymerization of acyl groups and glyceride molecules; change in specific refraction and the ratio of percentages by weight polymeric acyl groups to polymeric glyceride molecules. N.R.C. No. 3322. Part of this paper was presented at the Protective Coatings Section, Chemical Institute of Canada, Montreal, June, 1952.     

Stand reaction of linseed oil

Several theories have been proposed concerning the stand oil reaction but no precise reaction scheme has been described. In this work, the stand reaction of linseed oil was characterized in order to determine the nature of the products formed during this reaction. Using complementary analytical techniques (more especially NMR and mass spectrometry), the existence of two different reactions was demonstrated: the Diels–Alder addition between fatty acid chains and the addition of a methylene radical on double bonds, followed by combination or elimination reactions.     

Synthesis and characterization of low viscous and highly acrylated epoxidized methyl ester based green adhesives derived from linseed oil

Both epoxidized linseed oil and transesterified epoxidized linseed oil were acrylated to form UV curable bio-based oligomers. The synthesis was confirmed by FTIR and ¹H NMR and oxirane oxygen content (OOC). The OOC value of epoxidized linseed oil was determined to be 8.2 % which was reduced to 8.0 % after transesterification confirming the retaining of epoxy groups. The lower OOC of acrylated epoxidized linseed oil (AELO) (2.1 %) and acrylated epoxy methyl esters (AEME) (0.9 %) revealed successful acrylation. The degree of acrylation in AEME was higher (~ 90 %) than AELO (~ 77%) and most importantly, the viscosity of AEME was much lower than AELO revealing better processability for industrial use.     

过氧化氢一步法制备环氧亚麻油工艺

报道了亚麻油在以石油醚为溶剂、磷酸为催化剂的条件下,经甲酸、双氧水环氧化,一步合成增塑剂——环氧亚麻油的一种新方法。该法反应条件温和,操作方法简单,反应时间较短,而且产物各项指标均可达到增塑剂标准：环氧值＞7.8,碘值＜10,酸值＜0.5。     

Trans-free margarine from highly saturated soybean oil

Highly saturated (HS) soybean oil (SBO), which contained 23.3% palmitic acid (C_16:0) and 20.0% stearic acid (C_18:0), was interesterified at 70°C in preparation for the processing of a trans-free margarine. High-performance liquid chromatography analysis of the triacylglycerides and analysis of the sn-2 fatty acid composition showed no further change after 10 min of interesterification. The interesterified HS SBO had a slip melting point of 34.5°C, compared with 9.5°C in the non-interesterified HS SBO, and increased melting and crystallization temperatures were found using differential scanning calorimetry. Analysis of solid-fat content by nuclear magnetic resonance revealed the presence of only a small amount of solids above 33°C. A 50:50 blend of interesterified HS SBO and SBO with a typical fatty acid composition was used to make the margarine. Compared to commercial soft-tub margarine, the maximal peak force on the texture analyzer of this blended margarine was about 2.3 times greater, the hardness about 2.6 times greater, and adhesiveness about 1.5 times greater. There were small but statistically significant differences (α=0.05) in the sensory properties of spreadability, graininess, and waxiness between the commercial and blended margarines at 4.5°C and, except for graininess, at 11.5°C. These very small differences suggest a potential use for HS SBO in margarine products.