Urakawa Osamu, Yasue Ayaka
Department of Macromolecular Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
Polymers (Basel). 2019 Jul 5;11(7):1153. doi: 10.3390/polym11071153.
We examined the composition and molecular weight dependence of the glass transition temperature in detail for two types of hydrogen bonding miscible blends: poly (2-vinyl pyridine)/poly (vinyl phenol) (2VPy/VPh) and poly (4-vinyl pyridine)/poly (vinyl phenol) (4VPy/VPh). Regarding the functional form of the glass transition temperature, , as a function of the weight fraction, we found a weak deviation from the Kwei equation for 2VPy/VPh blends. In contrast, such a deviation was not observed for the 4VPy/VPh blend. By relating the difference in the functional forms of between the two blend systems to the difference in hydrogen bonding ability, we proposed a modified version of the Kwei equation. As for the interaction parameter, in the Kwei equation, clear molecular weight dependence was observed for 2VPy/VPh blends: the lower the VPh molecular weight in the oligomer level, the higher the values, suggesting the higher hydrogen bonding formability near the polymer chain ends than the middle part of a polymer chain.
聚（2-乙烯基吡啶）/聚（乙烯基苯酚）（2VPy/VPh）和聚（4-乙烯基吡啶）/聚（乙烯基苯酚）（4VPy/VPh）的玻璃化转变温度的组成和分子量依赖性。关于玻璃化转变温度作为重量分数函数的函数形式，我们发现2VPy/VPh共混物与Kwei方程存在轻微偏差。相比之下，4VPy/VPh共混物未观察到这种偏差。通过将两种共混体系之间函数形式的差异与氢键能力的差异联系起来，我们提出了Kwei方程的修正版本。至于Kwei方程中的相互作用参数，在2VPy/VPh共混物中观察到明显的分子量依赖性：在低聚物水平下，VPh分子量越低，值越高，这表明聚合物链末端附近的氢键形成能力高于聚合物链中部。
