Liu Xinyue, Qi Xiaojun, Guan Yupeng, He Yingying, Li Shuai, Liu Hongxia, Zhou Li, Wei Chun, Yu Chuanbai, Chen Yunhua
College of Material Science & Engineering, Guilin University of Technology, Guilin 541004, China.
College of Material Science & Engineering, Guilin University of Technology, Guilin 541004, China.
Carbohydr Polym. 2019 Nov 15;224:115202. doi: 10.1016/j.carbpol.2019.115202. Epub 2019 Aug 13.
We report here the development of transparent and strong polymer composites reinforced by unmodified cellulose nanofibrils (CNFs) with a Pickering emulsion gelation strategy. The CNFs entangle and firmly stabilize on the surface of emulsion droplets containing polymethyl methacrylate (PMMA) solution, leading to the gelation of the emulsions. CNFs/PMMA composites were generated via vacuum filtration and solvent washing of the gel and a subsequent two-step hot pressing. The composites contained a unique self-assembled two-tier hierarchy of CNFs networks and demonstrate promising transparency, tensile strength, flexibility, and an extremely low thermal expansion. Remarkably, these properties are highly tunable with varying the concentration of CNFs and the volume ratio of the water to oil phase. This work offers a facile route to realize the well dispersion of unmodified CNFs in hydrophobic polymer matrix and achieve high performance of polymeric materials reinforced by CNFs.
我们在此报告通过皮克林乳液凝胶策略开发的由未改性纤维素纳米纤维（CNF）增强的透明且坚固的聚合物复合材料。CNF在含有聚甲基丙烯酸甲酯（PMMA）溶液的乳液滴表面缠结并牢固稳定，导致乳液凝胶化。通过对凝胶进行真空过滤和溶剂洗涤以及随后的两步热压制备了CNF/PMMA复合材料。该复合材料包含独特的自组装双层CNF网络层次结构，并表现出良好的透明度、拉伸强度、柔韧性和极低的热膨胀率。值得注意的是，通过改变CNF的浓度以及水相和油相的体积比，这些性能具有高度可调性。这项工作提供了一条简便的途径，以实现未改性CNF在疏水性聚合物基体中的良好分散，并实现由CNF增强的聚合物材料的高性能。
