Co-operative diffusion of semi-dilute solutions, concentrated solutions and swollen networks for polystyrene in dibutylphthalate
Co-operative diffusion of semi-dilute solutions, concentrated solutions and swollen networks for polystyrene in dibutylphthalate
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聚苯乙烯在邻苯二甲酸二丁酯中的半稀溶液、浓溶液和膨胀网络的协同扩散
DOI：
10.1016/0032-3861(83)90179-9
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发表时间：
1983
期刊：
影响因子：
4.6
通讯作者：
T. King
中科院分区：
文献类型：
--
作者：
S. Candau;I. Butler;T. King
用光子相关光谱法测定了分子量为11万~ 3.6× 10.6的聚苯乙烯溶液在直链邻苯二甲酸二丁酯中的扩散常数与聚合物体积分数和温度的关系。在半稀释范围内，协同扩散常数c随着聚合物体积分数Φ的增加比理论预测的要小得多，除了在高温下（T大于或等于100°c），它遵循边际溶剂特征的Φ 12定律。这种效应可以描述为摩擦系数的增强，这也可以通过体积分数随温度升高而降低的dc来证明。在膨胀网络中也观察到同样的效应，但在膨胀平衡条件下，这种效应会大大减弱。
The diffusion constant of solutions of polystyrenes of molecular weight ranging from 110 000 to 3.6× 10 6 in straight-chain-dibutylphthalate has been measured by photon correlation spectroscopy as a function of polymer volume fraction and temperature. In the semi-dilute range the co-operative diffusion constant D c exhibits a much smaller increase with the polymer volume fraction Φ than theoretically predicted, except at high temperatures (T⩾ 100° C) where it follows a Φ 1 2 law characteristic of a marginal solvent. This effect can be described to an enhancement of the friction factor, which is also demonstrated by a decrease in D c occurring at a volume fraction which increases with temperature. The same effect is observed in swollen networks but it is strongly reduced for swelling equilibrium conditions.