摘要
通过计算机模拟和实验系统研究了两亲性嵌段高分子的相态结构及其自组装行为。研究结果表明两亲性嵌段高分子体系在热力学上存在许多的亚稳态。这决定了其自组装结构和过程依赖体系的初始条件、退火速率、以及外场的作用等。比如,两亲性ABA三嵌段聚合物在选择性溶剂中通过自组装所形成囊泡的动力学过程依赖体系的退火速率。慢速退火条件下囊泡的形成是通过亲水链段分别向聚集体的表面和中心扩散形成的,而在快速退后条件下囊泡的形成是通过膜的弯曲和封口形成的。此外,还发现均匀流场中所形成囊泡的均匀性明显好于非均匀流场中的,而且剪切速率越高囊泡尺寸越小、形貌越均匀。另一方面,环状组装体在低搅拌速率下通过棒状胶束的头尾相接形成的,而在高速搅拌下通过囊泡的破裂形成的。
Phase structure of amphiphilic block copolymer and its self-assembly behavior have been studied by both computer simulation and experiment. The results show that the many metastalbe states exist in the system. This determines that the self-assembly of amphiphilic block copolymers and its pathway depends on initial condition, annealing rare and external fields. As examples, some typical results are introduced.
引文