Process for the preparation of a block copolymer composition

Abstract

This invention relates to a process for preparing a block copolymer composition, wherein it comprises following successive steps: a step in which a vinyl aromatic monomer is polymerized in a reactor in the presence of an inert hydrocarbon solvent and organolithium initiator until depletion of the monomer to generate a living polymer; a step in which a conjugated diene monomer is added to the above polymer to synthesize a living diblock copolymer; a step in which a portion of polymerization terminator is added to partially inactivate the living diblock copolymer; steps in which a conjugated diene monomer and aromatic vinyl monomer are sequentially added to generate a mixture of living triblock copolymer and inactivated diblock copolymer; a step in which a polymerization terminator is added to complete the reaction. This invention has advantages of providing easy, wide-range and fine control of block copolymer compositions in a reactor via well-controlled termination reactions during the sequential block copolymerization.

Dependencies are inferred from the claim text.