| 摘要 |
Living monolithio polymers are coupled by the action of certain novel coupling agents (e.g., nitrobenzene, sulfur, dimethyl terephthalate, acrylonitrile, maleic anhydride). For example, styrene is first polymerized in benzene with n-butyl lithium catalyst to form a styrene polymer block (S) followed by addition of butadiene to form a butadiene polymer block (B) copolymerized with the styrene block in the form of a living monolithio block copolymer SB(-) Li(+). Then a coupling agent, such as nitrobenzene, is added, forming coupled block copolymer SBCSB where C is a residue of the coupling agent. Coupling of three molecules of living polymer is possible with maleic anhydride, or of four molecules with dimethyl terephthalate.
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