PROCESS FOR MAKING A COUPLED BLOCK COPOLYMER COMPOSITION AND THE RESULTING COMPOSITION

摘要

This invention relates to a process far making a hydrogenated block copolymer, comprising the steps of: a) reacting a living lithium-terminated polymer having the formula P-Li, where P is a copolymer chain having at least one polymer block A composed of one or more mono alkenyl arenes having 8 to 18 carbon atoms and at least one polymer block B composed of one or more conjugated dienes having 4 to 12 carbon atoms, with an alkoxy silane coupling agent having the formula Si-(OR)4, where R is selected from, linear and branched alkyl radicals, and where the molar ratio of Si to Li is between 0.4 and 0.55, thereby forming a coupled block copolymer composition; b) optionally hydrogenating the coupled block copolymer composition; and c) recovering the resulting block copolymer composition. It also relates to the resulting composition containing low levels of uncoupled polymer and having a substantial linear character.