正电子湮没技术研究双酚-A聚碳酸酯薄膜的结晶行为

发布时间：2018-02-07 09:21

本文关键词： 聚碳酸酯结晶正电子湮没自由体积　出处：《武汉大学学报(理学版)》2017年06期 　论文类型：期刊论文

【摘要】：双酚-A聚碳酸酯的半刚性结构使其热结晶速率慢且结晶度低.在有机溶剂丙酮的蒸汽氛围下,聚碳酸酯会以较快的速率完成结晶过程.本文采用X射线衍射(XRD)和正电子湮没寿命谱(PALS)研究了丙酮蒸汽诱导聚碳酸酯薄膜结晶行为和微结构转变.随着丙酮蒸汽作用时间增长,XRD图谱显示27.3°处的衍射峰有"出现-消失-出现"现象,而PALS结果则显示正-电子偶素(o-Ps)寿命是增大趋势,o-Ps强度是先增大后减少.研究结果分析认为,双酚-A聚碳酸酯薄膜经丙酮蒸汽作用发生"结晶-重结晶"现象;重结晶引起了平均自由体积孔洞尺寸继续增大,而自由体积浓度却进一步增大.
[Abstract]:Semi rigid structure of bisphenol -A polycarbonate makes its thermal slow crystallization rate and crystallinity is low. In steam atmosphere organic solvent acetone, polycarbonate will complete the crystallization process at a faster rate. This paper uses X ray diffraction (XRD) and positron annihilation spectroscopy (PALS) of acetone vapor induced crystallization of the films and polycarbonate the micro structure change. With acetone steam time increases, XRD showed that the diffraction peak of 27.3 degrees at the emergence of the "lost -" phenomenon, while PALS showed positive positronium (o-Ps) life is increased, the strength of o-Ps is increased first and then decreased. The results of analysis, bisphenol -A polycarbonate the effect of acetone vapor film "crystallization and recrystallization phenomenon; recrystallization caused by the average free volume hole size continues to increase, while the free volume concentration is further increased.

【作者单位】：武汉大学物理科学与技术学院;武汉大学湖北省核固体物理重点实验室;
【基金】：国家自然科学基金资助项目(11375132,2042015kf0190)
【分类号】：O633.14;TB383.2

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