【摘要】 本文研究了聚甲基丙烯酸甲酯（PMAA）的立构规整性与T₈的关系,结果表明立构单元分布和含量均对T₈有显著影响。应用前文导出的理论关系,进一步处理了T₈和构象参数实验数据,用这种简单方法计算得的无扰尺寸温度系数和实验值一致。由此推论,不同立构PMMA链的T₈之差反映了它们局部择优链构象的不同。更多还原

【Abstract】 The glass transition temperature (Tg) and unperturbed demensions of PMMAs with Bernoulli distribution of stereoregular diads were measured. It was found that T, of PMMA depends not only on their tacticity but also on the distfibution type of the diads. Therefore, the linearized equation representing the dependence of Tg on the content of iso-, syndic- and heterotriads can only be used for the PMMA with the same type of stereodiads distribution.The theoretical relationship proposed in our previous papei; was applied to analyse the data of Tg and unperturbed dimension for PMMAs having various tacticities. The temperature coefficients, dlno2/dT, calculated by this method show a good agreement with the experimental ones-更多还原