PURPOSE: To improve the heat stability, oxidation stability, etc., of a polyolefin resin, by adding a specified phenolic compound and a specified sulfur compound to the resin.
CONSTITUTION: A mixture is prepared by mixing (A) tetrakis-[methylene-3-(3- methyl-5-t-butyl-4-hydroxyphenyl)propionato]-methane with (B) a sulfur compound of formula I (wherein R1 is a 3W18C alkyl, and R2 and R3 are each H or a 1W 6C alkyl) in a weight ratio of A to B of 1:0.5W15. About 0.01W5pts.wt. resulting mixture is added to 100pts.wt. polyolefin resin (e.g., polypropylene resin) to obtain the purpose stabilized polyolefin resin composition. Component A is prepared by the esterification of pentaerythritol, and component B is prepared by the reaction of pentaerythritol with an aldehyde of formula II.
YAGO SHINICHI
TAKAHASHI YUUKOU
