Nie Yijing, Gu Zhouzhou, Zhou Qiang, Wei Ya, Hao Tongfan, Liu Yong, Liu Rongjuan, Zhou Zhiping
Institute of Polymer Materials, School of Materials Science and Engineering, Jiangsu University , 301 Xuefu Road, Zhenjiang 212013, China.
J Phys Chem B. 2017 Jul 13;121(27):6685-6690. doi: 10.1021/acs.jpcb.7b02861. Epub 2017 Jun 29.
Nowadays, it is a research hotspot to realize the controllability of polymer crystal structure in polymer nanocomposites. However, polymer crystals induced by two-dimensional filler always exhibit random orientation, which somewhat limit the improvement of physical properties of polymer materials. In the current paper, dynamic Monte Carlo simulations were performed to explore the methods preparing crystals with uniform orientation. Heterogeneous nucleation of deformed polymer loops grafted on two-dimensional filler can induce the appearance of a special nanohybrid shish-kebab (NHSK) structure, in which the two-dimensional filler acts as "shish" and induces the formation of crystals with uniform orientation. The grafted deformed chains are first heterogeneously nucleated on filler surface, and then free chains participate in crystallization, resulting in the formation of the NHSK structure. The NHSK structure can only be formed in the systems with high interfacial interactions at high temperatures or moderate interfacial interactions at moderate temperatures or low interfacial interactions at low temperatures. The method proposed here can be used to achieve the controllability of polymer crystal orientation in experiments.
如今，实现聚合物纳米复合材料中聚合物晶体结构的可控性是一个研究热点。然而，二维填料诱导的聚合物晶体总是呈现随机取向，这在一定程度上限制了聚合物材料物理性能的提高。在本文中，进行了动态蒙特卡罗模拟以探索制备具有均匀取向晶体的方法。接枝在二维填料上的变形聚合物链的异相成核可以诱导一种特殊的纳米杂化串晶（NHSK）结构的出现，其中二维填料充当“串”并诱导形成具有均匀取向的晶体。接枝的变形链首先在填料表面异相成核，然后自由链参与结晶，从而形成NHSK结构。NHSK结构只能在高温下具有高界面相互作用、中等温度下具有中等界面相互作用或低温下具有低界面相互作用的体系中形成。这里提出的方法可用于在实验中实现聚合物晶体取向的可控性。
