Rice husk-derived porous carbon/silica particles as green filler for electronic package application

Bio-based porous carbon/silica particles (denoted as RH-carbon/silica) were successfully prepared from agricultural waste rice husk by using acid-hydrothermal treatment and pyrolysis under nitrogen condition. As green filler, the cure behavior, thermal-mechanical properties, and thermal conductivity of the epoxy-carbon/silica biocomposites at different filler contents (5, 9, 17, 29 wt %) were characterized. Because of superior surface properties (surface area, porosity, and silica segment) and high content of carbon component in the RH-carbon/silica, the characteristics of the biocomposites were significantly improved with the increase of the filler content. At 29 wt % of filler content, the epoxy biocomposites exhibit lower curing temperature (148 °C), lower CTE (42 ppm/°C), higher T_g (123 °C), higher storage modulus (4059 MPa), and higher effective thermal conductivity (0.29 W/mK). In brief, the RH-carbon/silica particles that can serve not only as reinforcing agent but also as thermal transport medium used in epoxy composite, is a green and high-performance filler for this purpose.