Effect of crystallization and liquid–liquid phase separation on phase‐separation kinetics in poly(ethylene‐co‐vinyl alcohol)/glycerol solution
Effect of crystallization and liquid–liquid phase separation on phase‐separation kinetics in poly(ethylene‐co‐vinyl alcohol)/glycerol solution
复制标题
结晶和液-液相分离对聚(乙烯-共-乙烯醇)/甘油溶液中相分离动力学的影响
DOI：
10.1002/polb.10361
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发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Douglas R. Lioyd
中科院分区：
文献类型：
--
作者：
Mengxiang Shang;H. Matsuyama;T. Maki;M. Teramoto;Douglas R. Lioyd
在光散射下检查了聚（乙烯-共-乙烯醇）（EVOH）-甘油的聚合物-稀释剂体系的液-液热致相分离。对于乙烯含量为38mol%的EVOH（EVOH38），观察到散射光强度的最大值，这表明通过旋节线分解（SD）发生了相分离。一般液-液相分离形成的结构的生长在SD中服从幂律标度关系。对于乙烯含量为32 mol%的EVOH（EVOH32），由于聚合物结晶导致液-液相分离。在这种情况下，结构生长表现出先形成结晶颗粒，然后由结晶引起的液-液相分离形成的液滴快速生长的特征行为。此外，在恒定冷却速率下通过光学显微镜测量通过相分离而生长的液滴。结晶后形成的相分离结构可以比正常液-液相分离形成的相分离结构生长得更快。
Liquid-liquid thermally induced phase separation of the polymer-diluent system of poly(ethylene-co-vinyl alcohol) (EVOH)-glycerol was examined under light scattering. For EVOH with an ethylene content of 38 mol % (EVOH38), maxima of the scattered light intensity were observed that indicated that phase separation occurred by the spinodal decomposition (SD). The growth of the structures formed by the general liquid-liquid phase separation obeyed a power-law scaling relationship in SD. For EVOH with an ethylene content of 32 mol % (EVOH32), the liquid-liquid phase separation resulted from the polymer crystallization. In this case, the structure growth showed the characteristic behavior in which the crystalline particles were initially formed, and then the droplets formed by the liquid-liquid phase separation induced by the crystallization grew rapidly. Furthermore, the growth of the droplet by the phase separation was followed by an optical microscope measurement at a constant cooling rate. The phase-separated structure formed after the crystallization can grow faster than that formed by the normal liquid-liquid phase separation.