Stabilization of vinyl resins

摘要

Synthetic resin compositions based on vinyl polymers or copolymers are stabilized against degradation by both heat and light by the incorporation therein of a 1,4-dihydropyridine derivative represented by the general formula: <IMAGE> wherein R represents a straight or branched-chain saturated or unsaturated alkyl radical containing from 9 to 22 carbon atoms. The stabilizer can be present in an amount of from 0.01 to 0.5 percent by weight, based on the vinyl resin. The vinyl resin may be, for example, polyvinyl chloride, a vinyl chloride-vinyl acetate copolymer or a vinyl chloride-vinylidene chloride copolymer. The stabilized vinyl resins can be used in the manufacture of food packaging materials and containers and also of flooring tiles and recording discs. Some of the dihydropyridine derivatives are novel compounds.