Faculty of Physics, Warsaw University of Technology, Koszykowa 75, 00-662, Warsaw, Poland.
Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141, 02-507, Warsaw, Poland.
Sci Rep. 2022 Nov 9;12(1):19038. doi: 10.1038/s41598-022-23735-3.
Insufficient homogeneity is one of the pressing problems in nanocomposites' production as it largely impairs the properties of materials with relatively high filler concentration. Within this work, it is demonstrated how selected mixing techniques (magnetic mixer stirring, calendaring and microfluidization) affect filler distribution in poly(dimethylsiloxane)-graphene based nanocomposites and, consequently, their properties. The differences were assessed via imaging and thermal techniques, i.a. Raman spectroscopy, differential scanning calorimetry and thermogravimetry. As microfluidization proved to provide the best homogenization, it was used to prepare nanocomposites of different filler concentration, whose structural and thermal properties were investigated. The results show that the concentration of graphene significantly affects polymer chain mobility, grain sizes, defect density and cross-linking level. Both factors considered in this work considerably influence thermal stability and other features which are crucial for application in electronics, EMI shielding, thermal interface materials etc.
在纳米复合材料的生产中，不均匀性是一个紧迫的问题，因为它会极大地损害具有相对高填充浓度的材料的性能。在这项工作中，展示了如何选择混合技术（磁搅拌混合、压延和微流化）影响基于聚二甲基硅氧烷-石墨烯的纳米复合材料中的填料分布，从而影响其性能。通过成像和热技术，例如拉曼光谱、差示扫描量热法和热重分析，评估了差异。由于微流化被证明提供了最佳的均化效果，因此使用它来制备不同填充浓度的纳米复合材料，研究了它们的结构和热性能。结果表明，石墨烯的浓度显著影响聚合物链的迁移率、晶粒尺寸、缺陷密度和交联水平。本工作中考虑的这两个因素对热稳定性和其他在电子、电磁干扰屏蔽、热界面材料等应用中至关重要的特性有很大影响。
