Instrumented Impact Testing of Kenaf Fiber Reinforced Polypropylene Composites: Effects of Temperature and Composition

An instrumented Izod test was used to investigate the effects of fiber content, coupling agent, and temperature on the impact performance of kenaf fiber reinforced polypropylene (PP). Composites containing 0—60% (by weight) kenaf fiber and 0 or 2% maleated polypropylene (MAPP) and PP/wood flour composites were tested at room temperature and between -50 ^° C and +50 ^° C. At room temperature, kenaf greatly reduced energy to maximum load (EML) in reversed notch tests but had little effect in notched tests. MAPP improved all test values. At —25 ^° C, PP specimens changed from ductile to brittle. Kenaf composites containing MAPP consistently yielded higher EML values than did both unfilled PP specimens and wood flour composites in notched impact tests, over the temperature range investigated. The EML values for kenaf composites were about half those for unfilled PP specimens in reversed notch tests at room temperature, but performance was similar at low temperatures.