Abstract: This paper studied the mechanical properties of the Kosteletzkya virginica bast fiber reinforced polypropylene composites. The influence of fiber content on the tensile and flexural properties was studied and compared with those reinforced with ramie fiber composites. It showed that with increasing Kosteletzkya virginica bast fiber content, the tensile strength and modulus increased, and the bending strength and modulus was first increased and then decreased with the maximum at 40 % fiber content. When the fiber content was 30 %, the mechanical properties of Kosteletzkya virginica bast fiber reinforced composites were inferior to those reinforced with ramie fiber, except for the tensile modulus.

Key words: polypropylene, Kosteletzkya virginica bast fiber, fiber content, composite