Ries ME, Klein PG, Brereton MG, Ward IM
Interdisciplinary Research Centre in Polymer Science and Technology, University of Leeds, Leeds LS2 9JT, U.K.
Macromolecules. 1998 Jul 28;31(15):4950-6. doi: 10.1021/ma971860b.
A range of low-molecular-weight linear poly(ethylene oxide) chains with LiCF3SO3 have been examined via the transverse proton NMR relaxation. From the measured relaxation functions it is shown that the chains obey Rouse dynamics. This analysis gives the molecular weight of a Rouse statistical subunit and the fundamental Rouse relaxation time. It was found that varying the temperature and salt concentration had no effect on the size of a Rouse statistical segment and therefore none on the conformation of the chains. The temperature dependence of the fundamental Rouse relaxation time was found to be well modeled by the Vogel-Tamman-Fulcher equation. The NMR-measured correlation times were then successfully used to predict the glass transition temperature as measured by DSC. The main conclusion of this paper is that under the addition of salt the ideal glass transition temperature T0 is found to remain constant or indeed to slightly decrease.
通过横向质子核磁共振弛豫研究了一系列带有LiCF3SO3的低分子量线性聚环氧乙烷链。从测量的弛豫函数可知，这些链符合劳厄动力学。该分析给出了劳厄统计亚基的分子量和基本劳厄弛豫时间。结果发现，改变温度和盐浓度对劳厄统计链段的大小没有影响，因此对链的构象也没有影响。发现基本劳厄弛豫时间的温度依赖性可以用Vogel-Tamman-Fulcher方程很好地模拟。然后，核磁共振测量的相关时间被成功用于预测差示扫描量热法测量的玻璃化转变温度。本文的主要结论是，在添加盐的情况下，理想玻璃化转变温度T0保持不变或实际上略有下降。
