A study of the thermomechanical properties of carbon fiber-polypropylene composites

Short fiber composites were produced using polypropylene as matrix and polyacrylonitrile (PAN)-based fibers or vapor grown carbon fibers (VGCF) as reinforcement. The strength, stiffness, and coefficient of thermal expansion (CTE) of the composites were measured. The VGCF-composites showed strength and CTE that are competitive with those of "conventional" PAN-fiber composites, but the stiffness was marginally lower. Micromechanical modeling of the PAN composite properties gives results consistent with the measurements. The models can be used to infer the apparent VGCF-properties from their composites.