Yin Xinyi, Li Qiang, Wang Haishui, Yang Wengang, Zhou Xi, Zhang Han, Lyu Weibang
School of Chemistry and Chemical Engineering, South China University of Technology Guangzhou 510641 China.
Innovation Center for Advanced Nanocomposites, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences Suzhou 215123 China
RSC Adv. 2021 Jul 7;11(39):23892-23900. doi: 10.1039/d1ra03711k. eCollection 2021 Jul 6.
Various preforms of carbon nanotubes (CNTs), such as fibers, yarns, or buckypapers (BP), have been developed over the last few years in order to fabricate advanced nanocomposites containing a high volume fraction of the reinforcing phase. However, a homogeneous dispersion and an even isolation of CNTs during the fabrication process of many preforms such as BP is often challenging, while the poor interaction between CNTs and the matrix also limits the final performance of the nanocomposites. Herein, a new route to overcome these two challenges simultaneously has been demonstrated based on an active dispersant (noted as Py-PEI) developed through the quaternization reaction of pyrene derivatives (Py-Br) and polyethylenimine (PEI). The existence of pyrene groups leads to the formation of π-π stacking with CNTs, successfully hindering the re-aggregation of dispersed CNTs. Meanwhile, the amine groups of Py-PEI can establish covalent bonds with epoxy, leading to an enhanced load transfer efficiency between CNTs and epoxy in the composites. Systematic characterization of both fabricated BP and BP-reinforced nanocomposites have been performed, with significantly enhanced CNT dispersion stability in water together with improved mechanical performance of the as-obtained BP/epoxy nanocomposites. This study provides a new strategy in fabricating high performance nanocomposites with the ease of nanofiller dispersion and enhanced reinforcing efficiency.
在过去几年中，人们开发了各种碳纳米管（CNT）预制件，如纤维、纱线或巴基纸（BP），以制造含有高体积分数增强相的先进纳米复合材料。然而，在许多预制件（如BP）的制造过程中，碳纳米管的均匀分散和均匀隔离往往具有挑战性，而碳纳米管与基体之间的不良相互作用也限制了纳米复合材料的最终性能。在此，基于通过芘衍生物（Py-Br）与聚乙烯亚胺（PEI）的季铵化反应开发的活性分散剂（记为Py-PEI），展示了一种同时克服这两个挑战的新途径。芘基团的存在导致与碳纳米管形成π-π堆积，成功地阻碍了分散的碳纳米管的重新聚集。同时，Py-PEI的胺基可以与环氧树脂建立共价键，从而提高复合材料中碳纳米管与环氧树脂之间的载荷传递效率。对制备的BP和BP增强纳米复合材料进行了系统表征，碳纳米管在水中的分散稳定性显著提高，同时所获得的BP/环氧树脂纳米复合材料的力学性能也得到改善。本研究为制备具有易于纳米填料分散和增强增强效率的高性能纳米复合材料提供了一种新策略。
