聚对苯二甲酸乙二酯形态结构的光散射研究

在不同结晶条件下,聚对苯二甲酸乙二酯样品出现了三种不同的光散射图形(正常球晶、异常球晶和混合球晶散射图形)。并假定正常球晶的光轴方向与半径垂直;异常球晶的光轴方向与半径夹+45°角或-45°角;混合球晶则是正常球晶与异常球晶叠加的结果。基于这些假定,按照Clough的计算公式,用二维球晶模型分别对具有上述各种光轴取向的球晶进行了计算。结果表明,计算出的H_v、V_v散射图形与实验所得的散射图形符合得很好。偏光显微镜的观察结果也进一步证实了这些模型的假定。

SMALL ANGLE LIGHT SCATTERING STUDIES ON THE MORPHOLOGY OF POLYETHYLENE TEREPHTHALATE

Three types of light scattering patterns (normal, abnormal and mixed) have been found in PET samples under different conditions of crystallization. In the normal pattern the optical axis is in the direction perpendicular to radius, while in the abnormal one it is the angles of approximate 45° and -45° to the radius. The mixed one is assumed to be the superimosition of the normal and abnormal ones. Based on these assumptions, calculation with a two-dimensional spherulite model for these orientations of optical axes were made ac-cording t Clough's squations. It is shown that the calculated Hv and Vv scattering patterns are satisfactorily in agreement with the experimental ones. Observations with polarized micros-copy have confirmed the model suggested.