Investigation of thermomechanical properties and matrix-filler interaction on polyimide/graphene oxide composites

We report, the preparation of nanocomposites having polyimide (PI) as matrix and graphene oxide (GO) as filler, analyses of matrixfiller interactions, and enhancements in thermomechanical properties of PI/GO as compared with pristine PI. The matrixfiller interactions were analyzed by H-1 NMR, X-ray photoelectron spectroscopy, and density functional theory calculations. The data suggested stronger matrixfiller interactions in PI/GO as compared with PI/G composites. The stronger matrixfiller interactions and homogeneous dispersion of fillers lead to a significant enhancement in mechanical properties in PI/GO nanocomposites. Thus, with just 1 wt% GO content, the modulus of PI/GO composite increased by similar to 106% as compared with pristine PI. Finally, thermal expansion coefficients of the nanocomposites are also investigated. A plausible hypothesis has been proposed in the text to explain the observed matrixfiller interactions and the subsequent property enhancements in nanocomposites. POLYM. ENG. SCI., 52:2530-2536, 2012. (C) 2012 Society of Plastics Engineers