Silane-modified MWCNT/PMMA composites – Preparation, electrical resistivity, thermal conductivity and thermal stability

Multiwalled carbon nanotubes (MWCNT) were modified using 3-isocyanato- propyltriethoxysilane (IPTES). Crosslinkable PMMA was prepared from MMA monomer and Vinyltriethoxysilane (VTES) (PMMA–VTES). The IPTES-modified MWCNT (Si-MWCNT) was mixed with the PMMA–VTES copolymer and crosslinked with catalyst to form Si-MWCNT/PMMA–VTES composites. The degree of condensation of tri-distribution structure of the Si-MWCNT/PMMA–VTES composites decreases as the Si-MWCNT content increases. The morphology of the Si-MWCNT/PMMA–VTES composites was analyzed by SEM and TEM. The MWCNTs were well dispersed in the PMMA–VTES matrix. Surface and volume electrical resistivity decreased as the MWCNT content increased. The thermal conductivity of the PMMA–VTES composites increased by 87.5% when 0.99 wt% Si-MWCNT content was added to neat PMMA–VTES. The thermal stability of the PMMA–VTES in nitrogen and air increased significantly even when a small quantity (0.5 wt%) of Si-MWCNT was added.