【摘要】 采用溶液铸膜法制备3μm～30μm的双酚A聚碳酸酯(BAPC)薄膜。在25℃、丙酮气相压力分别为25.0kPa、26.5kPa或28.0kPa下诱导BAPC结晶。实验结果表明:当丙酮气相压力高于25kPa时,BAPC结晶,且DSC测试谱呈现熔融双峰。随着诱导结晶时间的延长,或诱导压力的增大,晶体逐渐完善,晶粒的平均尺寸增大,结晶度也增大。广角X射线衍射结果证实丙酮气相诱导BAPC结晶得到的晶体是单斜晶系结构。当诱导结晶时间分别为1h和56h时,生成平均尺寸分别约为2μm和16μm的球晶。更多还原

【Abstract】 The influence of the induced time, the pressure of acetone vapor at 25 ℃ on the crystallization behaviors of various thickness films of bisphenol-A polycarbonate (BAPC) samples was investigated by DSC. The melting endothermic peak shifts to higher temperature and becomes sharper with the induced time increasing. The depression in low temperature melting peak is most likely due to the poor and defect crystal structure with smaller crystal size. The effects of the induced time and the pressure of acetone vapor on lamellas thickness and crystallinity of samples were discussed. The wide-angle X-ray diffraction (WAXD) measurement of average crystal dimensions normal to (020) and crystallinity were calculated for the samples, and the crystallinity measured by WAXD is in agreement with that by DSC. By means of polarized optical microscopy (POM), morphology of the samples for various induced time was observed. The nucleation process of crystallization occurres at the initial stage of vapor-induced crystallization. As the time increased from 1 to 56 h, developed spherulites with dimension from 2 μm to 16 μm was observed.更多还原