GB1006602A - Improvements in and relating to the production of resins - Google Patents

Abstract

A method of making drying oil modified alkyd resins comprises subjecting a drying oil to acidolysis with a polybasic acid, and reacting the acidolysis product with a polyol and a vinylidene compound. The acidolysis product may be reacted first with the vinyl compound and then with the polyol, or may be reacted simultaneously with the vinyl compound and polyol. When the polybasic acid comprises o-phthalic acid the acidolysis product is preferably treated first with a substantial portion of the polyol, and then with the remainder of the polyol and the vinyl compound. The drying oil may be linseed, soya or dehydrated castor oil. The polybasic acid may be a phthalic acid or phthalic anhydride, optionally with up to 10% of fumaric or maleic acid. The polyol may be glycerol, pentaerythritol or trimethylol propane. Specified vinyl idene compounds are styrene, vinyl toluene, acrylic and methacrylic esters such as methyl methacrylate, and mixtures of vinyl toluene with acrylonitrile. Reaction with the polyol and vinyl compound may be effected under reflux using e.g. styrene or an inert solvent such as xylene as entrainment solvent. Reaction with the vinyl compound may be effected in the presence of initiators, e.g. benzoyl peroxide and di-t.-butyl peroxide, and chain transfer agents, such as mercaptans and dipentene. Examples describe the preparation of reaction products from linseed oil, isophthalic acid and vinyl toluene with (I) pentaerythritol and (II) glycerol; and a mixture of soya bean oil and dehydrated castor oil with phthalic anhydride and glycerol and (III) styrene and (IV) styrene and acrylonitrile, and with (V) isophthalic acid, glycerol and methyl methacrylate.