| 摘要 |
PURPOSE:To provide the titled copolymer derived from p-methylstyrene and a maleic anhydride derivative, having excellent heat resistance, and suitable as a material to improve the heat resistance of PVC, etc. as well as for the applications in the fields of electrical appliance, automobile, etc. CONSTITUTION:The objective copolymer composed of (A) the constituent unit of formula I (the contents of p-, m- and o-methyl units are >=80mol%, <=20mol% and <=1mol%, respectively) and (B) the constituent unit of formula II (R and R' are H, 1-6C alkyl, 6-10C aryl or halogen) is prepared preferably by (1) thermally polymerizing p-methylstyrene or a methylstyrene mixture containing >=80mol% of p-methylstyrene continuously adding maleic acid (derivative) to the system for a time corresponding to 50-90% of the whole polymerization time, and (2) carrying out the reaction for a time corresponding to 50-10% of the whole polymerization time. |
