中文摘要：

研究了ABg型超支化聚合反应中的环化效应,给出高分子代数生长的微分动力学方程,并通过环化反应的内在特征确定了环化反应与分子间反应的速率常数.进而利用Monte Carlo模拟方法得到了树状高分子和含环高分子的数量、环的尺寸分布以及高分子数均和重均分子量等,讨论了环化效应对聚合体系平均特征的影响.结果表明,环化效应取决于单体体积分数、溶剂效应和官能度之间的协同作用,其中单体的体积分数在环化反应中起着主导作用,而溶剂效应和官能度之间则相互竞争.

英文摘要：

The effect of cyclization on the average properties of hyperbranched polymers formed in the polymerization system of ABgtype was investigated by the method of Monte Carlo simulation. In the system of interest with cyclization,a set of differential kinetic equations based on the generation growth of polymers was given. The simulation is then performed by using the intermolecular and intramolecular reaction rates deduced from the principle of statistical mechanics. Specifically,the number of treelike and cyclic polymers,the number of loops,size distribution,the number- and weight-average molecular weights were given. Furthermore,the effect of cyclization on the average properties of polymers was discussed. It is shown that the volume fraction of monomers plays an important role in cyclization,which determines whether the influence of solvent quality and functionality is significant or not. As a result,the cyclization depends in essence on the cooperation of the above three factors. It is expected that the present study is helpful to design the related materials.