Chemical epoxidation of a natural unsaturated epoxy seed oil fromVernonia galamensis and a look at epoxy oil markets

Since 1963, production of all epoxy esters has ranged from 60 to 150 million lb annually, a steady 7% of the 1 to 2 billion lb of annual plasticizer production. Growth rates in production averaged 4.3% for all plasticizers, 3.8% for all epoxy esters and 5.0% for epoxidized soybean oil (ESBO). ESBO accounted for 70–76% of total epoxy ester production (1963–1982). The natural liquid epoxy oil fromVernonia galamensis seed, with oxirane value (4.1%) and viscosity (100 cps) similar to some commercial epoxy fatty esters but with molecular weight similar to epoxidized vegetable oils, combines some of the properties of both commercial types. Chemical epoxidation ofVernonia oil raises the oxirane content to 8.2, intermediate between ESBO and epoxidized linseed oil (ELSO), while consuming less of the costly epoxidizing reagents. Epoxidation proceeds in stepwise fashion through partially epoxidized products, which are converted to final product. Since the major fatty components ofVernonia oil arecis-12,13-epoxy-9-octadecenoic (75%) and linoleic (13%) acids, further epoxidation produces fatty acids that are specifically epoxidized at the 9,10- and 12,13-positions, and the major product has 6 epoxy units per triglyceride molecule. The resulting mixture of products has compositional and physical properties distinctly different from commercial samples of ESBO and ELSO.     

Functionalization of soy fatty acid alkyl esters as bioplasticizers

The combination of various functional groups, such as epoxy, acetoxy, methoxy, thiirane, and aziridine, on the fatty acyl chain of soy fatty acid alkyl esters have been synthesized and evaluated as plasticizers in poly(vinyl chloride) (PVC) applications. Numerous synthetic procedures, such as epoxidation, methoxylation, acetylation, thiiration, and aziridination, were used for synthesizing multifunctional soy fatty acid alkyl esters. Epoxidized soybean oil fatty acid alkyl ester served as the key intermediate for functionalization. Partial or complete ring opening of the epoxide by reacting with methanol and the subsequent etherification or acetylation of the hydroxyl function produced epoxy, alkoxy, and acetoxy derivatives. The nucleophilic substitution of epoxide with sulfur by reacting with ammonium thiocyanate produced thiirane and epoxy thiiranes. Although the aziridine derivatives were synthesized by reacting unsaturated fatty acid alkyl esters with chloramine‐T, the compounds were fully characterized and their physical and analytical properties were determined. The high viscosity and darker color of aziridine and thiirane derivatives limit their usefulness, whereas the physical properties of the other derivatives were acceptable. The plasticizer evaluation of methoxy and acetoxy soy fatty acid esters (methyl and n‐butyl) demonstrated good compatibility with PVC, high efficiency (Shore hardness), and gelling properties were comparable to commercial plasticizer, di‐isoonyl phthalate. The abundant availability and cost‐effectiveness of starting materials and the readily adoptable chemical processes make the fatty acid ester derivatives viable bioplasticizers to replace the fossil fuel‐derived phthalates. J. VINYL ADDIT. TECHNOL., 23:93–105, 2017. © 2015 Society of Plastics Engineers     

Enzymatic epoxidation of soybean oil methyl esters in the presence of free fatty acids

Epoxides of soybean oil methyl esters (SMEs) are biodegradable, non‐toxic, and renewable epoxy plasticizers. The objective of the present work was to investigate the effects of free fatty acids on the enzymatic epoxidation of SMEs. The results showed that the epoxidation of SMEs depended on the type of the added free fatty acid. For saturated (≤C_18:0) and monounsaturated free fatty acids, the epoxy oxygen group content (EOC) of SMEs increased with increasing carbon chain length of free fatty acids; for branched‐chain unsaturated free fatty acids, the EOC of SMEs decreased in the presence of hydroxyl group (OH) and hydroperoxide (OOH) of free fatty acids; the EOC of SMEs decreased with increasing number of double bonds of free fatty acids. The maximum EOC and the initial epoxidization rate (V₀) linearly decreased with increasing peroxide value of SMEs. The highest EOC (6.87 ± 0.3%) of SMEs was obtained using behenic acid as reaction material, which was similar with that of stearic acid (EOC 6.75 ± 0.2%).     

Some fatty esters as plasticizers and fungicides for natural rubber

The prepared n-fatty alcohols from petroleum sources are esterified with a dibasic acid series (malonic, succinic, glutaric and adipic) or phthalic anhydride, giving the corresponding C₁₂ fatty esters. The prepared C₁₂ fatty esters were formulated with natural rubber. The drying time, some mechanical properties and fungitoxicity of the prepared film samples were examined. The conventional dibutyl phthalate plasticizer was used for the purpose of comparison. The data obtained indicate that the prepared fatty esters can be used as plasticizers with antifungal activity for natural rubber. ©1997 SCI     

Vernolic acid esters as plasticizers for polyvinyl chloride

The methyl, propyl, butyl, isobutyl, hexyl, cyclohexyl, octyl, and 2-ethylhexyl esters of vernolic (epoxyoleic) acid, a naturally-occurring epoxy acid, were prepared and evaluated as plasticizers of polyvinyl chloride. All the esters showed good compatibility. The data indicated that they are excellent low temperature plasticizers having T_f temperatures below −50C. They also have the added advantage of greatly increasing the heat stability of the polyvinyl chloride and improving the light stability. The results are compared with DOP and other epoxy-containing plasticizers now being used commercially. These esters should not only be useful as primary plasticizers but also in combination with other plasticizers as plasticizer-stabilizers. Presented at the AOCS Meeting. Cineinnati, October 1965 E. Utiliz. Res. Dev. Div., ARS, USDA.     

Castor Epoxy Fatty Acid Alkyl Ester Estolides as Bioplasticizers for Poly(Vinyl Chloride)

Epoxy fatty acid alkyl ester estolides were synthesized from castor oil to be used as biobased plasticizers for poly(vinyl chloride) (PVC) as a safer replacement for phthalate plasticizers. Initially, castor oil was transesterified with methanol or n-butanol to quantitatively yield castor fatty acid alkyl esters. Acetylation of hydroxyl function with acetic anhydride led to the formation of estolide. The unsaturation was epoxidized, resulting in a bifunctional epoxy fatty acid alkyl ester estolide. The bioplasticizers were compounded with PVC and were evaluated for their functionality and compared with commercial phthalate plasticizer diisononyl phthalate (DINP) and nonphthalate 1,2-cyclohexanoic acid diisononyl ester (DINCH). The bioplasticizers showed excellent gelation, efficiency, and compatibility, as well as plastisol viscosity and thermal properties, comparable to or better than the plastisols prepared with commercial controls DINP and DINCH. The volatility of the methyl ester was inferior to the butyl ester. Both compounds showed low water resistance properties. Further evaluation of the butyl ester under tropical conditions of high temperature and humidity confirmed limited compatibility. This indicates that the castor epoxy fatty acid ester estolides would be better suited for applications that do not come in contact with water for prolonged periods, such as flooring, artificial leather, wiring, or wall coverings.     

Epoxidation of modified natural plasticizer obtained from rice fatty acids and application on polyvinylchloride films

In recent years, much research effort has been driven to develop alternative plasticizers for medical and commodity plastic materials. In this study, a modified natural plasticizer, synthesized by esterification of rice fatty acids, was modified by epoxidation with peroxy acid generated in situ. Two natural epoxidized plasticizers were obtained, using peracetic acid (NP‐Ac) and peroctanoic acid (NP‐Oc) as reagent. PVC films after addition of these natural epoxidized plasticizers presented fairly good incorporation and plasticizing performance, as demonstrated by results of mechanical properties, T_g values (as shown by DSC), optical microscopy, exudation, and migration tests, FTIR and X‐ray diffraction obtained for plasticized PVC films. NP‐Ac plasticizer presented enhanced plasticizing performance compared with NP‐Oc, probably due to a higher epoxidation degree obtained in the reaction with peracetic acid. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Reactions of conjugated fatty acids. V. Preparation and properties of diels-alder adducts and their esters fromtrans,trans-conjugated fatty acids derived from soybean oil

Summary Soybean fatty acids were conjugated with alkali, and the contained, conjugated dienoic acids were isomerized with iodine to thetrans,trans configuration. Adducts were prepared from thesetrans,trans-conjugated acids by condensation with maleic anhydride and acrylic acid. The adducts were isolated, purified, and converted to esters by using a variety of alcohols, including methyl, ethyl,n-propyl,n-butyl, and allyl alcohols. Esters made from saturated alcohols were converted into the corresponding epoxy derivatives. All of the esters (except allyl) and all of the epoxy esters were compatible with an equal weight of polyvinyl chloride and appeared to be primary plasticizers for this plastic. The epoxy esters were effective in inhibiting heat deterioration of polyvinyl chloride. Presented at fall meeting. American Oil Chemists' Society, September 23–26, 1956, Chicago, Ill.     

Plasticizing properties of esters of monohydric alcohols and tall oil fatty acids

Tall oil fatty acid esters prepared as intermediates in an epoxy ester plasticizer program were similarly evaluated as low-temp plasticizers in polyvinyl chloride resins. Performance characteristics as primary and secondary plasticizers in polyvinyl sheeting and extruded tapes were determined on esters from methyl to heptadecyl tallate. Results indicate that these materials impart low-temp properties which would make them of value as low-cost plasticizers in extruded and molded products where light and heat stability are not primary factors.     

Epoxidation ofLesquerella andLimnanthes (Meadowfoam) oils

Lesquerella gordonii (Gray) Wats andLimnanthes alba Benth. (Meadowfoam) are species being studied as new and alternative crops. Triglyceride oil from lesquerella contains 55–60% of the uncommon 14-hydroxy-cis-11-eicosenoic acid. Meadowfoam oil has 95% uncommon acids, includingca. 60%cis-5-eicosenoic acid. Both oils are predominantly unsaturated (3% saturated acids), and have similar iodine values (90–91), from which oxirane values of 5.7% are possible for the fully epoxidized oils. Each oil was epoxidized withm-chloro-peroxybenzoic acid, and oxirane values were 5.0% (lesquerella) and 5.2% (meadowfoam). The epoxy acid composition of each product was examined by gas chromatography of the methyl esters, which showed that epoxidizedL. gordonii oil contained 55% 11,12-epoxy-14-hydroxyeicosanoic acid, and epoxidized meadowfoam oil contained 63% 5,6-epoxyeicosanoic acid, as expected for normal complete epoxidation. Mass spectrometry of trimethylsilyloxy derivatives of polyols, prepared from the epoxidized esters, confirmed the identity of the epoxidation products and the straightforward nature of the epoxidation process. Synthesis and characterization of these interesting epoxy oils and derivatives are discussed.     

Secondary Plasticizers for Polyvinyl Chloride (PVC) Epoxidized Esters

Abstract

The synthesis of epoxy esters of 3-pentadecenyl phenol a low cost indigeneous raw material is described. These epoxy esters have further been evaluated as secondary plasticizers for PVC. Epoxidized 3-pentadecenyl-phenyl linoleate seems to be an attractive candidate as a secondary plasticizer amongst the epoxy esters evaluated.     

用可再生性原料合成环氧增塑剂的研究进展

综述了利用可再生性原料合成环氧中性油脂和环氧脂肪酸甲酯的研究现状及应用前景,介绍了化学法和酶法制备环氧增塑剂的反应原理,根据催化剂的不同,阐述了其合成方法的进展。突出了高效环保型催化剂——脂肪酶的应用。     

Analysis of hydroxylated fatty acids from plant oils

A novel process has been described recently for the preparation of hydroxylated fatty acids (HOFA) and HOFA methyl esters from plant oils. HOFA methyl esters prepared from conventional and alternative plant oils were characterized by various chromatographic methods (thin-layer chromatography, high-performance liquid chromatography, and gas chromatography) and gas chromatography-mass spectrometry as well as¹H and¹³C nuclear magnetic resonance spectroscopy. HOFA methyl esters obtained fromEuphorbia lathyris seed oil, low-erucic acid rapeseed oil, and sunflower oil contain as major constituents methylthreo-9,10-dihydroxy octadecanoate (derived from oleic acid) and methyl dihydroxy tetrahydrofuran octadecanoates, e.g., methyl 9,12-dihydroxy-10,13-epoxy octadecanoates and methyl 10,13-dihydroxy-9,12-epoxy octadecanoates (derived from linoleic acid). Other constituents detected in the products include methyl esters of saturated fatty acids (not epoxidized/derivatized) and traces of methyl esters of epoxy fatty acids (not hydrolyzed). The products that contain high levels of monomeric HOFA may find wide application in a variety of technical products.     

Synthesis and evaluation of some fatty esters as plasticizers and fungicides for poly(vinyl acetate) emulsion

n-Fatty alcohols (average molecular weight 187), prepared from n-paraffins, were treated with a series of dibasic acids such as malonic, succinic, glutaric, adipic and phthalic anhydride to give the corresponding fatty esters. The prepared fatty esters were formulated with poly(vinyl acetate) emulsion and used as films or textile coatings. Tests such as rate of drying, mechanical properties and resistance to micro-organisms were carried out. Samples of poly(vinyl acetate) plasticized with dibutyl phthalate were also prepared and evaluated for the purpose of comparison. The antifungal activity of these compounds was studied. The results obtained indicate that the prepared fatty esters can be used not only as plasticizers but also as fungicides and in some respects they are better than the conventional dibutyl phthalate plasticizer.     

N,N-Bis(2-Acyloxyethyl) amides of long chain fatty acids as plasticizers

A series of N,N-bis-(2-acyloxyethyl) amides and a few related derivatives have been prepared wherein a long chain fatty acid or fatty acid mixture comprises 33 mole percent of the total acyl groups present: the other 66 mole percent being either a short chain aliphatic or aromatic acyl group. Both ordered and random diesteramides have been prepared. All have been tested as plasticizers for vinyl chloride copolymers. Some are acceptable as nitrile rubber softeners and cellulose acetate plasticizers. The ordered diesteramides give the best overall performance as plasticizers, but it is possible to achieve acceptable performance levels in semi-ordered diesteramides. Presented at the AOCS meeting in New Orleans, La., 1962. A laboratory of the So. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.     

Epoxidation of alkyl esters of 12,13-epoxyoleic acids and evaluation of the diepoxides as plasticizers for poly(vinyl chloride)

Methyl, propyl, butyl, isobutyl, hexyl, cyclohexyl, octyl and 2-ethylhexyl esters of 9,10:12,13-diepoxystearic acid were prepared by peracetic acid oxidation of the corresponding esters of 12,13-epoxyoleic acid. Using a 60 mole per cent excess of peracid at 30 C in chloroform as solvent, epoxidation was complete in 5 hr. A small aqueous phase was observed in the reaction mixture which decreases the amount of peracid available for reaction. This is due to the water and H₂O₂ present in the commercial peracetic acid used. Thin-layer and gas chromatographic analysis showed that the diepoxides formed as isomers. These did not react quantitatively with HBr by the Durbetaki method. Isomers of methyl and propyl diepoxy esters were separated by crystallization. The methyl (pure and mixed isomers), isobutyl, 2-ethylhexyl and octyl (all mixed isomers) diepoxy esters were evaluated as plasticizers of poly (vinyl chloride). Delta values showed that these esters have good compatibility. Results are compared with commercial epoxidized soybean oil control. These diepoxy esters show better low temperature properties and have higher migration and volatility values than the control. They are more efficient plasticizers than the control. The liquid isomer of the methyl ester, as well as the 2-ethylhexyl ester, should be useful as primary plasticizers and in combination with other plasticizers as plasticizer stabilizers. E. Utiliz. Res. Dev. Div., ARS, USDA.     

乌桕籽油制备环氧脂肪酸异辛酯的工艺

选用具有丰富不饱和键的乌桕籽油为原料,采用了水解、酯化、环氧化等一系列反应合成了环保型增塑剂环氧脂肪酸异辛酯。并通过正交试验研究了脂肪酸异辛酯的环氧化工艺,确定了合成最佳工艺为:每百克脂肪酸异辛酯,甲酸30.37g,双氧水131.49g,反应温度65℃,反应4h后环氧值可达5.71。通过红外确定了产物的构成并考察了拉伸、热稳定性等性能,结果表明环氧脂肪酸异辛酯较邻苯二甲酸二辛酯(DOP)具有更好的热稳定性和挥发迁移性。     

Minor components ofLesquerella fendleri seed oil

Routine analysis of fatty ester fractions ofLesquerella fendleri oil suggested the presence of epoxy compounds and other minor components. By a combination of open silica column and high performance liquid chromatography (HPLC) fractionations of the methyl esters prepared from the oil, these constitutents were isolated and then characterized by thin-layer chromatography-mass spectrometry (GC-MS—electron ionization, EI, and chemical ionization, CI) and nuclear magnetic resonance (NMR—¹H and¹³C). Three epoxy acids, 15,16-epoxy-9,12-octadecadienoic, 9,10-epoxy-12-octadecenoic and 9,10-epoxy-octadecanoic, were found. Hydroxy acids present included a C-22 homologue of lesquerolic acid (16-hydroxy-12-docosenoic acid) and 14,15-dihydroxy-tricosanoic acid. Other minor ocmponents included four sterols, brassicasterol, campesterol, β-sitosterol and stigmasterol, and a series of saturated and unsaturated fatty acids up to C30. Visiting postdoctoral scientist sponsored by the government of India.     

Recent advances in in-situ epoxidation reactions with resin catalysts

Summary Two new resin catalyst systems forin-situ epoxidation have been described. One technique features the continuous circulation of the reaction mixture through a fixed resin catalyst bed. The other, a simple, practical and economical process, employs expendable amounts of resin catalyst. Yields of 75–85% epoxy ester with very little residual unsaturation were readily obtained. Presented at the 29th fall meeting of the American Oil Chemists’ Society, October 10–12, 1955, Philadelphia, Pa.