Abstract
This paper presents the effect of heat-treatment on mechanical properties of natural fiber reinforced plastics. First, in order to investigate the effect of oxygen during heat-treatment on tensile strength of natural fibers, Manila hemp fibers were heat-treated in air and Ar. As a result, in the case of heat-treatment in Ar, the tensile strength of Manila hemp fibers was able to resist at higher temperature than that in air. Next, tensile strength of heat-treated Manila hemp fiber reinforced plastics was examined. The results showed that the tensile strength of Manila hemp fiber reinforced plastics also decreased at the same temperature as shown in the Manila hemp fibers heat-treated in air, although Manila hemp fibers embedded in resin. This temperature dependence is derived from the remained oxygen in lumens.
