Polymeric peroxide, polymerization initiator and method for production of block copolymer

摘要

An ester type polymeric peroxide has a peroxide group of the formula (I): a group of the formula (I′) and a group of the formula (II) wherein X stands for one member selected from the group consisting of -CH₂-CH₂-, -C≡C- and continuously bound such that I and I′ occur randomly in alternation with II, having a (I) : (I′) molar ratio in the range of from 9 : 1 to 1 : 9 and the [(I) + (I′)] : (II) molar ratio in the range of from 6 : 4 to 4 : 6, and having an average molecular weight in the range of from 1,000 to 20,000, a polyerization initiator for vinyl type monomer comprising said ester type polymeric peroxide and method for the production of a block copolymer of vinyl type monomer by said polymerization initiator.