Interpolymerization products of aromatic vinyl compounds, glyceride oils, and oil-alkyds

In polymerizing a mixture of an aromatic vinyl compound and an oil-modified alkyd resin containing a radical of a higher fatty acid with a conjugated double bond, the tendency to gelatinize is greatly reduced by incorporating an animal or vegetable oil containing an unsaturated fatty acid radical. Specified vinyl compounds are styrene, a -methyl styrene and nuclear-halogenated styrenes. the alkyd resin may be prepared from glycol, glycerol, pentaerythritol, trimethylol ethane, trimethylol propane, mannitol, sorbitol or hexane-triol with phthalic, succinic, adipic or maleic acid, and the conjugated fatty acid radical may be derived from dehydrated castor oil or tung oil. The alkyd resin may also contain the radicals of monobasic higher fatty acids, e.g. palmitic, oleic and linoleic acids. Suitable animal and vegetable oils are olive, groundnut, palm, rape, cottonseed, poppyseed, soyabean, sardine, codliver, menhaden, pilchard, linseed, perilla, tung and oiticica oils. Polymerization is preferably effected in solution under reflux, suitable solvents being carbon tetrachloride, benzine, oil of turpentine, cyclohexanone, toluene, xylene, ethyl benzene and solvent naphtha. A peroxide catalyst, e.g. benzoyl peroxide, may be present. The products may be used in making air-drying varnishes.