Comparison of Carbon Nanofibers and Activated Carbon on Carbon Dioxide Foaming of Polystyrene

Carbon nanofibers (CNFs) and activated carbon (AC) are two forms of carbon with different shape and surface properties. These two carbon materials were used as additive/nucleation agents in the polystyrene extrusion foaming process. Carbon dioxide (CO2) was used as the blowing agent. Both additives showed better properties than talc in thermal insulation foams based on foam density, thermal conductivity, IR transmission, thermal stability, and compressive modulus. Overall, CNFs are better than AC due to the unique foam structure ('pseudo-bimodal' foam structure) of PS+ CNFs foams observed in this study.