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分析了一般的非等速率自缩合乙烯基聚合反应(SCVP)所生成的超支化聚合物体系的结构单元和支化度.详细计算了支化度随反应进程(A基团转化率x)、活性的A*和B*基团反应速率比(r)和活化剂/单体物质的量比(α)的变化关系.对任何指定的r和α组合,DB随x的增加而单调增加,对确定的x,当αx/(1+x~(1/2))时,DB随r的变化不再是单调的,有极大值,但无论怎样的r和α组合,最大的支化度都只有0.5.要想进一步提高产物的支化度,可以在反应终了时,在体系中再加入适当的其它单体,使活化基团全部反应掉,从而可使支化度达到2α/(1+α).
The structural unit and the degree of branching of the hyperbranched polymer system generated by the general non-uniform rate self-condensation of vinyl polymerization (SCVP) were analyzed.The degree of branching was calculated in detail with the progress of the reaction (A group conversion x) Activity A * and B * group reaction rate ratio (r) and activator / monomer mass ratio (α) changes for any combination of r and α, DB increases monotonically with the increase of x, For a given x, DB decreases monotonously with the increase of r when α x / DB changes with r is no longer monotonous, with maximum, but no matter what kind of combination of r and α, the maximum degree of branching is only 0.5. To further improve the degree of branching products can be at the end of the reaction, In the system and then add the appropriate other monomers, so that the activation group all reacted, so that the degree of branching can reach 2α / (1 + α).