Positronium Annihilation Lifetime and Dynamic Mechanical Studies of γ-Relaxation in BPA-PC and TMBPA-PC Plasticized by TOP
Positronium Annihilation Lifetime and Dynamic Mechanical Studies of γ-Relaxation in BPA-PC and TMBPA-PC Plasticized by TOP
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TOP 增塑的 BPA-PC 和 TMBPA-PC 中的正电子湮灭寿命和 γ 弛豫动态力学研究
DOI：
10.1021/ma980203w
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发表时间：
1999
期刊：
影响因子：
5.5
通讯作者：
A. Rizos
中科院分区：
文献类型：
--
作者：
C. Xiao;J. Wu;L. Yang;A. Yee;L. Xie;D. Gidley;K. Ngai;A. Rizos
采用正电子湮灭寿命谱（PALS）研究了以磷酸三（2-乙基己基）磷酸（TOP）为稀释剂分子的玻璃状BPA-PC和TMBPA-PC的结构和动力学性质。结果表明，对于BPA-PC/TOP共混物，在TOP添加量不超过10 wt %时，总孔体积分数不敏感，但随着TOP浓度的增加，总孔体积分数有所增加。然而，在TMBPA-PC/TOP共混物中，观察到不同的趋势。当TOP浓度达到15%时，总孔洞体积分数单调下降，之后从15%到20%略有增加。动态力学松弛也被用于监测共混物的动力学。这部分工作的动机是耦合模型的预测（在实验测量之前），即添加TOP对BPA-PC和TMBPA-PC的γ-弛豫时间有相反的影响。事实上，通过恒频动态力学测量发现，当γ-弛豫…
Positronium annihilation lifetime spectroscopy (PALS) was employed to study the structure and dynamic properties of glassy BPA-PC and TMBPA-PC containing tris(2-ethylhexyl) phosphate (TOP) as diluent molecules. For BPA-PC/TOP blends, the results showed that the total hole volume fraction is insensitive to the addition of TOP up to 10 wt % but increases at higher TOP concentration. However, in the case of TMBPA-PC/TOP blends, a different trend was observed. The total hole volume fraction decreases monotonically with TOP concentration up to 15% and thereafter increases slightly from 15 to 20%. Dynamic mechanical relaxation was also used to monitor the dynamics of the blends. This part of the work was motivated by a prediction of the coupling model (made before the experimental measurement was carried out) that addition of TOP should have opposite effects on the γ-relaxation times of BPA-PC and TMBPA-PC. Indeed, it was found by dynamic mechanical measurement at constant frequency that, while the γ-relaxation...