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用扭辫仪(TBA)和线膨胀仪测定了一组规则的星形聚苯乙烯的玻璃化转变温度T_g和T_(ll)松弛。两种实验方法的结果表明:支链分子量相同的星形结构聚合物的T_g随着支化度增加而升高,但也发现星形聚苯乙烯的T_g却低于具有相同分子量的线形聚苯乙烯的T_g·液_1-液_2松弛温度T_(ll)和损耗峰的强度也依赖其支化度。与以二乙烯基苯为凝胶核的星形结构相比较,证实了后者的双T_g转变。
The glass transition temperatures T_g and T_ (11) relaxation of a set of regular star polystyrene were measured by TBA and linear dilatometer. The results of the two experimental methods show that the T_g of star-shaped polymers with the same molecular weight increases with the increase of the degree of branching, but it is also found that the T_g of the star-shaped polystyrene is lower than that of the linear polystyrene with the same molecular weight Ethylene T_g · liquid _1- liquid _2 relaxation temperature T_ (ll) and loss peak intensity also depends on its degree of branching. Compared with the star structure with divinylbenzene as the gel nucleus, the latter double T_g transition was confirmed.