| 摘要 |
Process for the preparation of a block copolymer comprising a first polymer block of an anionically polymerizable monomer selected from the group consisting of monovinyl aromatic hydrocarbons, conjugated dienes and mixtures thereof, and a second polymer block of polydimethylsiloxane, said process comprising the steps of: (a) combining at a temperature of from -10 to 60 DEG C into one reaction mixture at least the anionically polymerizable monomer (s), an organoalkali metal initiator, hexamethylcyclotrisiloxane and a polar promoter, thus effecting polymerization of the anionically polymerizable monomer(s); (b) allowing the polymerization to proceed until the block polymerization of the anionically monomer(s) and the subsequent cross-over reaction between the living polymer chains and the hexamethylcyclotrisiloxane is complete; (c) raising the temperature to a temperature in the range of from 60 to 120 DEG C, thus effecting polymerization of hexamethylcyclotrisiloxane at the end of the living polymer block obtained in step (a); and (d) terminating the polymerization. |
