GB548212A - Improvements in or relating to the production of interpolymers of heat blended oil varnishes and polymerisable esters - Google Patents

Abstract

548,212. Vinyl resins. DU PONT DE NEMOURS & CO., E. I. March 28, 1941, No. 4183. Convention date, March 29, 1940. [Class 2 (iii)] Varnishes and coating compositions having reduced frosting tendencies are produced by the copolymerization of an oil varnish, obtained by heat blending a frosting drying oil, e.g. chinawood or oiticica oil, and a gum or resin, and an ester of an alpha-methylene open chain mono-carboxylic acid. Esters specified are methyl, ethyl, propyl, butyl, octyl, furfuryl, dodecyl, octadecyl, isobutyl, cyclohexyl, #- methoxyethyl, 2-nitropropyl, benzyl, 2-methyl- 2-nitropropyland #-cyanoethyl α-chloroacrylates α-phenylacrylates, acrylates or methacrylates. The varnish is obtained by blending the oil with 5 to 50 per cent. of a natural or synthetic gum or resin at 225-230‹C. The copolymerization is preferably carried out in the presence of a catalyst e.g. benzoyl peroxide and an inert solvent, e.g. toluene and xylene, the mixture being heated at 100-125‹C. for about three hours and the excess ester and solvent removed by distillation under vacuum. Other water polymerizable monomers, e.g. styrene, vinyl acetate, methyl vinyl ketone, vinyl chloride, maleic anhydride may be added. In examples (1) a chinawood oil-Amberol F-7 (an oil soluble rosin-modified phenol-formaldehyde resin) varnish is prepared by heating 1400 parts chinawood oil and 160 parts Amberol F-7 in an open vessel for 30 minutes to 225‹C. The products are mixed with 1200 parts methvl methacrylate, xylene, and benzoyl peroxide and heated for 2¢ hours at 98-106‹C. An enamel is prepar ed from the product by adding titanium dioxide, antimony oxide, and a mixture of cyclohexanone and toluene and grinding in a ball mill for 64 hours ; (2) the varnish is prepared by heating together rosin and chinawood oil to 225‹C. for 15 minutes.