摘要
本工作用差动扫描量热计(DSC)、动态粘弹仪(DMA)、密度梯度、激光小角散射仪(SALS)和光学解偏振仪研究了国产聚碳酸酯/聚对苯二甲酸乙二醇酯(PC/PET)共混物的相容性和结晶行为。DSC研究结果表明,共混物中在PET含量为60％以下时,只有一个玻璃化转变温度(T_g),说明共混物是完全相容的;在PET含量大于60％时,共混物呈现出两个玻璃化转变温度,并发生内移,说明共混物是部分相容的。用DMA测试也得到同一结果。共混物中PET的结晶动力学与一般结晶高聚物相似,等温结晶前期符合Avrami方程,等温结晶后期偏离Avrami方程。
The miscibility and crystallization behaviour of PC/PET blends , over the whole composition, have been studied by means of differential scanning calorimetry ( DSC ) , dynamic mechanical (DMA) , density measurements, small angle light scattering (SALS) and depolarized light insensity method. The result show that the miscibility of PC/PET blends dependent upon composition of blends. The glass transition temperature of PC/PET blends as a function of blends composition measured by DSC and DMA , the results are illustrated in figure 1-2 respectively, they are good agreement.Density data for the PC/PET blends molded at 270℃and 300℃ are summerized in figure 3. the highest molding temperatures resulted in slight increases in density, as expected from increased.miscibility. The greatest deviation from linearity is observed at high PC levels at which DSC and the dynamic mechanical results has indicated the best miscibility.Melt isothermal crystallization kinetics of PC/PET blends has been studied by JJY- 1 crystallization rate equipment. By depolerized light intensity results according to the Avrami equation in primary periods crystallization, however crystallization deviate from the Avrami equation in the secondary periods. The Avrami exponent and crystallization rate constant k-were determined. For PC/PET blends n=2.9~4.3, combined with the SALS results it is concluded that the crystallization is still spherulite in nature. The morphology of spherulite was confirmed by SALS. (Figure 6, The Hv, patterns of SALS for PC/PET blends) .
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
1991年第2期110-114,共5页
Polymer Materials Science & Engineering
关键词
聚碳酸酯
PET
共混物
相容性
结晶
polycarbonate, polyethylene terephthalate, blend, miscibility , crystallization behaviour.
