The Study of Multi-walled Carbon Nanotube Surface and Matrix Structure for Thermal Conductive Composite Material

Abstract

Two kinds of surface-modified MWCNT/Al2O3/ETDS composites, cured pad and uncured grease, were fabricated for high-thermal-conductivity materials application. MWCNTs were modified using aminoproplytriethoxysilane (APTES) and dodecylamine after acid treatment. The reaction mechanism of APTES and the surface structure of MWCNT was controlled using different reaction conditions. The effect of surface modification on the thermal conductivity was confirmed based on a 70 wt% Al2O3/ETDS composite. The thermal conductivity was found to be dependent on the composite type and surface structure of the modified MWCNTs; the amine-terminated MWCNTs showed the highest thermal conductivity among the pad type composites, while long carbon chain-terminated MWCNTs showed outstanding performance among the grease type composites. Moreover, the maximum processable MWCNT content was also influenced by the surface modification; structurally similar silanol grdups affected the molecular mobility of the ETDS resin and they had the highest MWCNT content under the same process conditions.