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In this paper, the kinetic method was used to study the polymerization of butadiene initiated by NdCl_3·3i-PrOH-AlEt_3 catalyst system, at-70, -30 and 0℃. Results obtained indicated that there are no both reactions of detectable transfer limiting molecular weight of polymers and irreversible termination with deactivation of propagation centers. It was found that polymers produced had narrow molecular weight distributions (MWD) and extremely high cis-1,4 content, and that the living chain had a very long lifetime. Block copolymers of butadiene and isoprene were prepared and characterized by means of GPC, ~(13)C NMR, and IR. It was fully proved that the polymerization of butadiene initiated by the rare earth catalyst under these conditions had a living polymerization nature.
In this paper, the kinetic method was used to study the polymerization of butadiene initiated by NdCl 3 · 3i-PrOH-AlEt 3 catalyst system, at-70, -30 and 0 ° C. Results obtained indicated that there are no two reactions of detectable transfer limiting molecular weight of polymers and irreversible termination with deactivation of propagation centers. It was found that polymers produced had narrow molecular weight distributions (MWD) and extremely high cis-1,4 content, and that the living chain had a very long lifetime. Block copolymers It was fully demonstrated that the polymerization of butadiene was initiated by the rare earth catalyst under these conditions had a living polymerization nature.