Mechanical research of carbon nanotubes/PMMA composite films

Abstract

Carbon nanotybes (CNTs) are one of the best candidates for reinforcing the next generation of high-performance nanocomposites owing to their excellent mechanical properties. In this study, CNTs were dispersed in poly-methymethacrylate (PMMA) gel to enhance Its mechanical strength. CNTs/PMMA composite films were fabricated using direct mixing and sonication. FTIR was utilized to observe the chemical structure and functional groups of the material components. The morphological feature and phase structure were observed via scanning electron microscope. A nanoindenter system was also applied to investigate the mechanical properties of composite films by a conventional method. CNTs were chemically treated by Immersing them In acidic solutions to ensure extensive dispersion in the surrounding matrix. Most of the CNTs were dispersed uniformly therein. The effective dispersion of CNTs improves the mechanical performance of the composite film, wheras the poor dispersion reduces the performance. The solvent, solubility and attractive intermolecular forces, such as hydrogen bonds and Van Der Waal forces affect the dispersion of the CNTs. The carbonyl group, which was found on the composite film, contributed to the formation of a covalent bond between PMMA and the CNTs. The mechanical interaction between CNTs and the polymer was very complex. It was also governed by the interface interaction. The mechanical properties of the composite films improved as the concentration of CNTs increased. ©2008 Society of Plastics Engineers.