聚甲基苯乙烯侧基结构对特征比的影响

The Effect of Poly(α-methylstyrene) Chain with Side Group on Characteristic Ratio

在旋转异构态理论基础上,建立双侧基高分子链均方旋转半径的计算公式,由此得到聚甲基苯乙烯的均方旋转半径特征比与链长的关系,计算结果与实验数值十分一致。并研究了特征比与链内消旋比例的关系,因此可进一步研究考虑大侧基后链无规性的构象性质。

By the rotational isomeric state model and method, the mean-square of gyration < S^2 > for the disubstitutedpolymer chain is introduced, the characteristic ratio of < S^2 > vs. the degree of polymerization x for poly(α-methylstyrene)chain with two-side side group is calculated, which agrees with the experiment data. The ratio of < S^2 > against thepercentages of meso dyad W_m is also studied in this paper. The above methods can also be used to investigate theconfiguration-dependent properties for the atactic polymers with heavy side groups.