Tensile Properties of Short-Glass-Fiber-And Short-Carbon-Fiber-Reinforced Polypropylene Composites

This study investigated the tensile properties of short-glass-fiber- and short-carbon-fiber-reinforced polypropylene composites produced by extrusion compounding and injection molding. It found that increasing fiber volume fraction decreased mean fiber length due to fiber breakage during processing. A relationship between fiber volume fraction and mean fiber length was established using an exponential function. The tensile strength and modulus of the composites...

This study investigated the tensile properties of short-glass-fiber- and short-carbon-fiber-reinforced polypropylene composites produced by extrusion compounding and injection molding. It found that increasing fiber volume fraction decreased mean fiber length due to fiber breakage during processing. A relationship between fiber volume fraction and mean fiber length was established using an exponential function. The tensile strength and modulus of the composites were analyzed using rule of mixtures equations, introducing fiber efficiency factors that decreased with fiber volume fraction. Carbon fibers had lower efficiency than glass fibers. Failure strain also decreased with fiber volume fraction and could be related to fiber length, volume fraction, and radius.