METHOD OF STABILIZING STYRENE RESIN COMPOSITION

PURPOSE:To obtain the titled compsn. having excellent thermal stability, by adding an organotin maleate compd., a metal salt of a specified satd. dicarboxylic acid and zeolite A to a styrene resin compsn. contg. a halogen- contg. compd. CONSTITUTION:100pts.wt. flame-retardant styrene resin (A) contg. a halogen compd. obtd. by blending 10-150pts.wt. halogen-contg. compd. (e.g., PVC) with 100pts.wt. styrene resin (e.g., PS) is blended with 0.01-10pts.wt. organotin maleate compd. (B) of formula I or II [wherein R is a (cyclo)alkyl, an alkenyl, an aralkyl or an alkoxyalkyl; R is an alkyl; A is O or a group of formula III; k is 0 or 1; and l is a number of 1-10], 0.01-5.0pts.wt. metal salt of a satd. dicarboxylic acid (C) of formula IV (wherein M and M' are each a monovalent metal atom; and n is a number of 1-18) and 0.01-10pts.wt. zeolite A (D) of formula V (wherein X is a number of 0-6) in a weight ratio of B:C:D of 10-60:80-10:10-30.