高分子/单链高分子纳米粒子复合体系中的界面性质

高分子与纳米粒子复合是改善高分子材料性能的有效途径.近20年来关于高分子/纳米粒子复合物的研究引起了学术界广泛的兴趣.然而由于此类体系中的影响因素复杂,虽然学者们在相关材料性能的研究方面取得了重要进展,但是相关理论的发展却相对滞后,其中一个重要原因是实验上表征手段的缺失,导致对体系中纳米粒子与本体高分子链相互作用规律的认识(尤其是两者界面性质的认识)不够.本文总结和阐述了我们近几年利用分子动力学模拟技术研究高分子/单链高分子纳米粒子复合体系的主要结果,并围绕此类复合体系中的界面结构及动力学性质,讨论并总结了纳米粒子对本体高分子链的作用范围及影响规律,指出单链纳米粒子对熔体链的作用范围与纳米粒子的自身尺寸相当,而与熔体高分子链的分子量没有直接的关系.该结论将为纳米复合体系高分子理论的发展提供重要参考.

Interface Properties in Polymer/Single-chain Nanoparticle Composite

It is a practical method to control the property of polymer material by incorporating nanoparticles.Recently polymer/nanoparticle composites have drawn increasing attention in the polymer field.Although researchers have made apparent progresses in the property regulation of polymeric materials by incorporating nanoparticles,progress in the development of the corresponding theory is,however,greatly inhibited,due to the lack of proper characterization approach,especially on the interaction mechanism between various nanoparticles and matrix polymers mainly at their interface area.This mini review summarizes recent simulation results of our research group,especially on a polymer/nanoparticle composite system where nanoparticles are single-chain crosslinked polymer nanoparticles with the same chemical composition as matrix polymers.In particular,after a thorough discussion of the structure and dynamic properties at nanoparticle/polymer interface region,it is clear that the interface in this system,where nanoparticle and matrix polymer interact effectively,has approximately the same size as nanoparticle itself.This interface size has no dependence of matrix polymer chain length.We hope that this conclusion can be helpful for the further development of relevant theory for polymer/nanocomposite systems.