Phase separation, crystallization, and structure formation in immiscible polymer solutions
Phase separation, crystallization, and structure formation in immiscible polymer solutions
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不混溶聚合物溶液中的相分离、结晶和结构形成
DOI：
10.1002/app.1995.070571212
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发表时间：
1995
影响因子：
3
通讯作者：
W. Burghardt
中科院分区：
文献类型：
--
作者：
J. Zryd;W. Burghardt
相分离的形态和量热研究是在可结晶聚合物的不良溶剂溶液中进行的。在二苯醚和二苯甲烷溶液中研究了低支链含量的氢化聚丁二烯，其中平衡相图显示出聚合物的液-液相分离和结晶。重点放在使用低浓度热处理的样品制备方案上，预计两种相分离机制可能会影响所得的形态。使用斜坡冷却或等温结晶制备的样品表现出多孔结构，例如在膜材料中看到的那些，主要反映液相分离。然而，液体分层和结晶的不同动力学之间的相互作用提供了一种控制例如孔径大小的机制。斜坡冷却过程中的 DSC 研究表明存在与这些情况下预期存在的两个液相相关的两个离散结晶过程的证据。最后，高浓度样品显示出在单相聚合物溶液中球晶生长前沿诱导液相分离的形态学证据。 © 1995 约翰威利父子公司。
Morphological and calorimetric studies of phase separation have been carried out in solutions of a crystallizable polymer in poor solvents. Hydrogenated polybutadiene with low branch content was investigated in solutions with diphenyl ether and diphenyl methane, in which the equilibrium phase diagram exhibits both liquid–liquid phase separation and crystallization of the polymer. Emphasis is placed on sample preparation protocols using thermal treatments at low concentrations where it is anticipated that both phase separation mechanisms may influence the resulting morphology. Samples prepared using either ramp cooling or isothermal crystallization exhibit porous structures such as those seen in membrane materials, that predominantly reflect liquid phase separation. However, the interplay between the different kinetics of liquid demixing and crystallization provides a mechanism to control, for instance, pore size. DSC studies during ramp cooling showed evidence of two discrete crystallization processes associated with the two liquid phases expected to be present under these circumstances. Finally, high concentration samples showed morphological evidence of liquid phase separation induced at the growth front of spherulites in otherwise single-phase polymer solutions. © 1995 John Wiley & Sons, Inc.