聚合物溶液体系玻璃化转变温度与组成之间的关系

大量的文献报道了聚合物溶液体系中聚合物玻璃化转变温度(Tg)与组成之间的关系,这些理论公式大多是基于经典热力学理论,自由体积等理论得到的,这些结果在一些聚合物溶液体系中与实验结果是符合的.在一些聚合物-溶剂体系中,Tg与组成的关系之间出现了反常的"cusp"点,两个玻璃化温度等现象,部分理论值与预测值出现较大偏差,可以用自由体积理论和自聚集理论加以定性的解释.但是依然缺乏普遍的理论来解释和预测上面现象的发生,需要进一步完善和发展聚合物溶液体系中玻璃化转变温度与组成之间的关系.

The Relationship between Glass Transition Temperature and Composition in Polymer Solution Systems

Many literatures have reported the relationship between glass transition temperature and composition in polymer solutions.These equations are mostly based on classical thermodynamic theory,free volume theory,and the results derived from these equations are fit well in some polymer solution systems.In the curve of T_g vs.composition,anomalous "cusp" and double T_gs have been observed in some polymer-solvent systems,and these anomaly could be explained through free volume theory and self-concentration theory qualitatively,but the experimental results were quite different from the results derived from the equations,and these theories failed in some polymer solutions.So in order to account for and expect the occurrence of anomalous phenomena,general theories are needed to develop the relationship between T_g and composition and explain the "cusp".