Chain-end effect of living polymer in the coupling reactions for synthesis of block copolymers

Abstract

We have found that the yield in the coupling reaction of active polymer with silane coupling agent for the synthesis of block copolymers was effected by the reduction of the steric effect of the chain-end. Simply, the reduction of the reactivity of the living chain-end was less pronounced to reduce the coupling yield Thus, for the syntheses of block or starbranched copolymers via the coupling methodology, the reaction conditions such as a proper choice of the coupling agent and the steric effect of the chain-end should be carefully considered together.