GB774807A - Improvements in or relating to polyester resin compositions - Google Patents

Abstract

An unsaturated polyester and an aromatic monomer of the formula <FORM:0774807/IV(a)/1> wherein R is hydrogen or a C1 to C6 alkyl radical, R1 is halogen or a C1 to C6 alkyl radical and n is 0 to 4, are copolymerized in the presence of the order of 0.001 per cent of a wax compatible with the monomer but incompatible with the copolymer. The polyesters may be derived from maleic, fumaric, aconitic, mesaconic, citraconic, ethyl maleic, pyrocinchonic, xeronic, itaconic, "Carbic" (Registered Trade Mark), chloro-maleic and bromo-maleic acids, or mixtures, with or without specified saturated polycarboxylic acids and with conventional polyhydric alcohols. The monomer may be styrene; o-, m- or p-methyl- or -ethyl-vinyl benzene; o-, m- or p-chloro- or -bromo-styrene, p-iodostyrene, 2,5- or 3,5-dichlorostyrene, 2,4- or 2,5-dimethylstyrene, or 2,4,5-trimethylstyrene, or mixtures thereof. Waxes specified are paraffin, montan, ozokerite, ceresin, cannauba, candelilla, beeswax, sugar cane wax, lecithin, glycol stearate, stearic acid, polyglycol ester ("Flexowax") and glycol ester ("Acrawax"). Polymerization catalysts applicable are benzoyl, cyclohexanone, lauroyl, o,o1-dichlorobenzoyl, o,o1-dibromobenzoyl, acetone and methyl ethyl ketone peroxides, and t.-butyl and cumene hydroperoxides, optionally in conjunction with driers such as cobalt, cerium and lanthanum naphthenates. Premature polymerization may be prevented with inhibitors such as hydroquinone, t.-butyl catechol, 3-phenyl catechol, quaternary ammonium salts and t.-amine salts. Optional additives are fillers, such as silica, china clay, glass fibres and abrasives, and reinforcing material such as glass cloth or mat. The resins are useful as coatings on wood, paper, cloth, cork, plastics, ceramics, glass and metal, said coating comprising a film of wax on the surface and a decreasing concentration of wax in the polymer mass according to the distance from the surface. The wax film may be buffed off to give a hard resinous surface. The process may be used in the production of boats, automobile bodies, tanks, aircraft parts and sandpaper. Specification 735,488 is referred to.