GB642039A - Improvements relating to mixed phthalate esters and compositions incorporating them - Google Patents

Abstract

A mixed phthalate ester prepared by esterification of a fatty acyl-glycol mono-ester having from 8-18 carbon atoms in the acyl group with a mono-alkyl acid phthalate having from 1-12 carbon atoms in the alkyl group, e.g. preferably a phthalate ester of the formula <FORM:0642039/IV (a)/1> where R is alkyl or alkenyl of 1-12 carbon atoms, R1 is alkyl or alkenyl of 7-17 carbon atoms and n is 1-10 (see Group IV (b)), is employed as a plasticizer for butyl methacrylate and other acrylates, polystyrene, vinyl resins including the acetate, chloride, acetal, butyral and chloride-acetate copolymer, butadiene-acrylonitrile, butadiene-styrene, modified alkyd resins, phenol- and urea-formaldehyde resins, cellulose esters such as the acetate, acetate-butyrate, and nitrate, ethyl or benzyl cellulose and other ethers. In the general formula, R may be, for example, methyl, isopropyl, 2-ethylhexyl or lauryl, whilst R1CO- may be caprylyl, oleyl, or linoleyl, for example. The preferred ester is that in which R is butyl, R1CO- is derived from the fatty acids obtained on hydrolysis of coconut oil, i.e. mainly lauric acid, and n is 3. The plasticizers are incorporated by any known method into the polymer or resin. In the examples: (5-12), the preferred ester (see preceding) is incorporated, by the use of a mutual solvent, into the following: polyvinyl acetate, chloride-acetate, butyral, and chloride; polystyrene; ethyl cellulose; and butyl methacrylate polymer; (13), polyvinyl acetate is plasticized with a phthalate of the above general formula in which R is 2-ethylhexyl, R1CO- is derived from coconut fatty acids, and n is 3.ALSO:A mixed phthalate ester is prepared by esterification of a fatty acyl-glycol mono-ester having from 8-18 carbon atoms in the acyl group with a mono-alkyl acid phthalate having from 1-12 carbon atoms in the alkyl group. In a preferred form of the invention, a mixed phthalate ester of the formula <FORM:0642039/IV (b)/1> where R is alkyl or alkenyl of 1-12 carbon atoms, R1 is alkyl or alkenyl of 7-17 carbon atoms and n is 1-10, is prepared by esterifying the product obtained from phthalic anhydride and an alkanol or alkenol ROH of 1-12 carbon atoms (i.e. an acid phthalate) with a monoesterified ethylene glycol or polyethylene glycol of formula HO(C2H4O)nCOR1, the latter being prepared from R1COOH and HO(C2H4O)nH. Specified acids of formula R1COOH include caprylic, oleic, stearic and linoleic, whilst examples of the alcohol ROH include methanol, isopropanol, 2-ethylhexanol, isobutanol and lauryl alcohol. The acid R1COOH may be that obtained on hydrolyzing a natural fat. In the examples: (1) monobutyl phthalate (obtained from n-butanol and phthalic anhydride) is refluxed in naphtha in the presence of sulphuric acid with triethylene glycol of which one hydroxy group has been esterified with coconut fatty acids; by-product water is removed azeotropically; (2) n-butanol in the process of example (1) is replaced by 2-ethylhexanol; (3) mono-2-ethylhexyl phthalate is esterified with mono-oleyl ethylene glycol; (4) monomethyl phthalate is esterified with nonaethylene glycol, one hydroxyl group of which is esterified with capric acid.ALSO:A mixed phthalate ester prepared (see Group IV (b)) by esterification of a fatty acyl-glycol mono-ester having from 8-18 carbon atoms in the acyl group with a mono-alkyl acid phthalate having from 1-12 carbon atoms in the alkyl group, e.g. preferably an ester: <FORM:0642039/V/1> where R is alkyl or alkenyl of 1-12 carbon atoms, R1 is alkyl or alkenyl of 7-17 carbon atoms, and n is 1-10, is used to plasticize rubbery butadiene polymers, e.g. of chlorobutadienes such as chloroprene, polysulphide rubbers, and chlorinated rubber. The preferred ester is that in which R is butyl, R1CO-is derived from the fatty acid (mainly lauric) obtained from coconut oil, and n is 3. The plasticizers are incorporated into the rubber by any known method.