Author(s)

HIDEAKI KATOGI, KENICHI TAKEMURA

Abstract

This study investigated the flexural properties of unidirectional flax sliver reinforced polylactic acid by molding pressure and chitosan fiber addition. As a molding condition, the range of molding pressures was 1 MPa to 5 MPa. Molding was done using vacuum compression molding. The amount of added chitosan fiber was 5 wt.%. The chitosan fiber was applied to the flax sliver surface. After chitosan fiber addition, the flax sliver surface was observed using scanning electron microscopy (SEM). Static three-point flexural tests of the green composite were conducted at room temperature. As a result, the flexural strength and modulus of green composite increased with increased molding pressure. The flexural strength and the modulus of chitosan fiber with added green composite greatly decreased compared with those of green composite with no added chitosan fiber when the molding pressure was 5 MPa. SEM observations revealed many chitosan fibers on the flax sliver surface. The flexural properties of green composites were affected because matrix penetration among the flax fibers readily occurred at molding pressures. However, the flexural properties of the green composite with added chitosan fiber at a molding pressure of 5 MPa was lower than that of the green composite with no added chitosan fiber at a molding pressure of 5 MPa because matrix penetration between flax fibers was probably prevented by the chitosan fiber addition.

Keywords

chitosan fiber, green composite, flax sliver, flexural property, molding pressure, polylactic acid