Epoxy-acids triglycerides

Earls, J.D., White, J.E., Lopez, L.C. et al. (2007) Amine-cured co-epoxy fatty acid triglycerides fundamental structure-property relationships. Polymer, 48(3), 712-719. 

An epoxidized triglyceride oil was subjected to intercalation into an organically-modified clay, followed by acid-catalyzed curing of the epoxy-containing triglyceride, leading to the production of a new class of biodegradable-nanocomposites from inexpensive renewable resources. 

J. D. Earls, J. E. White, L. C. Lopez, Z. Lysenko, M. L. Dettloff and M. J. NuU, Amine-cured co-epoxy fatty acid triglycerides Fundamental structure-qjroperty relationships . Polymer, 2007,48,712-19. 

The fatty acid residues of ESO triglycerides are flexible, and steric hindrance has little or no effect on the reactivity of the epoxy groups. ESO rubbers with diamines are therefore characterized by a higher cross-link density and polarity. 

Fats and oils (triglycerides) from plants and animals are renewable sources of chemicals, but the amounts of the chemicals made from them are small compared with those made from petroleum and natural gas. This may change if biodiesel fuel (e.g., ethyl oleate) made by the alcoholysis of oils becomes common. Such esters may be useful as environmentally friendly solvents.50 Unsaturated oils, such as linseed oil, are the basis of oil-based paints, which cure by cross-linking through oxidation by air. Soaps are the potassium or sodium salts of the long-chain fatty acids obtained by the hydrolysis of the triglycerides. The dibasic dimer fatty acids obtained by the dimerization of oleic and linoleic acids (both Cig acids) are made into oligomeric fatty amides which are used to cure epoxy resins. The un-... 

Epoxidation of oleic and linoleic acid was readily achieved by treatment with the acetonitrile complex of hypofluorous acid (55). Phase-transfer-catalyzed biphasic epoxidation of unsaturated triglycerides was accomplished with ethylmethyldioxirane in 2-butanone (56). The enantioselective formation of an a,P-epoxy alcohol by reaction of methyl 13()S)-hydroperoxy-18 2(9Z,llfi) with titanium isopropoxide has been reported (57). An immobilized form of Candida antartica on acrylic resin (Novozyme 435) was used to catalyze the perhydrolysis and the interesterification of esters. Unsaturated alcohols were converted with an ester in the presence of hydrogen peroxide to esters of epoxidized alcohols (e.g., epoxystearylbutyrate) directly (58). Homoallyl ethers were obtained from olefinic fatty esters by the ethylaluminium-in-duced reactions with dimethyl acetals of formaldehyde, acetaldehyde, isobutyralde-hyde, and pivaldehyde (59). Reaction of 18 2(9Z, 12Z) with 50% BF3-methanol gave monomethoxy and dimethoxy derivatives (60). A bulky phosphite-modified rhodium catalyst was developed for the hydroformylation of methyl 18 1 (9Z)and 18 1(9 ), which furnished mixtures of formylstearate and diformylstearate (61). 

Vemonia oil, is a triglyceride of vernolic acid, an epoxy oleic acid. Vernonia oil is extracted from the seeds of Vemortia galamensis (or ironweed), a plant native to Eastern Africa. Vernonia seed contains atx>ut 40 to 42% oil of which 73 to 80% is vernolic acid. 

Acrylated oils can be obtained by converting the triglyceride double bonds into an epoxide. Afterwards, the epoxy groups are opened with acrylic acid to get hydroxy acrylated oils (74,77-79). 

In terms of chemical structure, few exceptions should be mentioned, since some fatty acids bear other types of functional groups, mainly epoxy rings and hydroxy moieties, triple bonds and ether functions [5], as discussed below. The fatty acid content in several common oils is given in Table 3.3 which, in addition, also provides the average number of DB per triglyceride unit. In the case of the more exotic castor, oiticica and tung oils, the main fatty acid residues are ricinoleic (87.5 per cent), licanic (74 per cent) of a-elaeostearic acids (84 per cent), respectively whose structures are provided in Scheme 3.2 below. 

Epoxy fatty acids also are found as components of triglycerides of the seed oils (Smith, 1970). This unusual fatty acid type is sporadically distributed in species of several taxo-nomically unrelated plant families. Z-12,13-Epoxyoleic acid (vemolic acid) (39) (Fig. 2.15) is biosynthesized from linoleic acid in the seeds of Xemnthemum anmum and Euphorbia lagascae (Hitchcock and Nichols, 1971). This compound and Z-9,10-epoxy stearate are synthesized by the introduction of oxygen from O2 across the double bonds of linoleic and oleic acids, respectively (Butt and Lamb, 1981 Morris, 1970). The biosynthesis of epoxy fatty acids is related to that of dihydroxy fatty acids, and epoxy fatty acids may serve as precursors for the latter type of compound. 

Vegetable Oils. Triglycerides form the principal component of most edible oils obtained from seeds and fruits small amoimts of free fatty acids and sterols occur also. As shown in Fig. 130, i, olive oil, a typical example, can be easily separated by adsorption TLC into these three fractions. Oils containing triglycerides of epoxy- and hydroxy-acids as well as those of the ordinary fatty acids show very characteristic... 

Vernolic (cz>12,13-epoxy-c/5 -9-octadecenoic) acid is an epoxy fatty acid which accumulates in the triglyceride of a few plant species such as Vemonia galamensis and Euphorbia lagascae. Vernolic acid has industrial applications such as in paints, plastic formulations, and protective coatings (1). 

By contrast, vernonia oil is a natural triglyceride that contains a bountiful supply of epoxy groups. It consists mainly of the triglyceride of 12, 13-epoxyoleic acid (Vernonia galamensis, native of Kenya, Africa, collected by Dr. R.E. Perdue, USDA) (18). 

Epoxy Plasticizer n (epoxides plasticizer) Any of a large family of plasticizers obtained by the epoxidation of vegetable oils or fatty acids. The two main types are (a) epoxidized unsaturated triglycerides, e.g., soybean oil and linseed oil and (b) epoxidized esters of unsaturated fatty acids e.g., oleic acid, or butyl-, octyl-, or decyl- esters. Most epoxy plasticizers have a heat-stabilizing effect and they are often used for stabilization in conjunction with other stabilizers. Epoxidized oils generally have good resistance to extrusion and migration and low volatility, but they cannot be used as sole plasticizers in unfilled vinyl compounds and hence are not considered to be primary plasticizers. Certain epoxidized soybean oils have been FDA-approved for food-contact use. 

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