摘要 |
Block copolymers are prepared by providing an initial anionically polymerizable monomer portion; anionically polymerizing the initial monomer portion to provide polymer chains with living ends, and contacting the polymer chains with m-bis(phenylethenyl)benzene (PEB), a coupling agent, to bring about substantial coupling. In preferred embodiments the polymer chain living ends are capped with an alpha -alkylstyrene or a ring-alkyl substituted alpha -alkylstyrene, wherein the alpha -alkyl groups contain between about 1 to about 20 carbon atoms, and the ring-alkyl groups have at least 2 carbon atoms. The coupling agents employed with the capped polymer chain living ends include PEB, p-dibromoxylene, terephthaloyl chloride, 1,4-dibromobutene; and the multifunctional epoxides, multifunctional isocyanates, multifunctional aziridines, multifunctional aldehydes, multifunctional ketones, multifunctional anhydrides, multifunctional esters, and polyhalides.
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