Department of Polymer Science, School of Chemistry and Chemical Engineering, State Key Lab of Coordination Chemistry, Nanjing University, 210023 Nanjing, China.
J Phys Chem B. 2023 Feb 2;127(4):822-827. doi: 10.1021/acs.jpcb.2c07085. Epub 2023 Jan 22.
Semicrystalline polymer materials are commonly strong yet tough after processed through fiber spinning, film stretching (or blowing), and plastic molding (or foaming), which are fundamentally related with strain-induced crystallization. This paper provides a personal perspective on thermodynamics and kinetics aspects of strain-induced polymer crystallization, mainly based on the author's recent research experience. The thermodynamic studies include homopolymers, random copolymers, solution polymers, and blend polymers. The kinetic studies cover three sequential crystallization stages, i.e., crystal nucleation, crystal growth, and postgrowth. The thermodynamic driving forces join with the kinetic barriers to determine the crystal nucleation mechanisms and the structure evolution at the molecular level, which yield unique polymer crystal morphologies from lamellar crystals to shish-kebab crystals and eventually fibril crystals. The resulting semicrystalline structures were discussed with their implications for the mechanical properties of products. Some future studies were briefly proposed.
半结晶聚合物材料经过纤维纺丝、薄膜拉伸(或吹塑)和塑料成型(或发泡)等处理后通常具有高强度和韧性,这与应变诱导结晶密切相关。本文主要基于作者的最新研究经验,提供了一个关于应变诱导聚合物结晶热力学和动力学方面的个人视角。热力学研究包括均聚物、无规共聚物、溶液聚合物和共混聚合物。动力学研究涵盖了三个连续的结晶阶段,即成核、晶体生长和后生长。热力学驱动力与动力学障碍相结合,决定了晶体成核机制和分子水平上的结构演变,从而产生了从层状晶体到串晶再到纤维状晶体的独特聚合物晶体形态。所得到的半结晶结构及其对产品力学性能的影响进行了讨论。最后简要提出了一些未来的研究方向。