Starch-grafted-polypropylene/kenaf fibers composites: Part 1: mechanical performances and viscoelastic behaviour

The mechanical performances and viscoelastic behaviour of starch-grafted-polypropylene/kenaf fibres composites were investigated on composites prepared by melt compounding and compression molding. In particular, the effects of various amounts (10,20 and 30 wt.%) of kenaf fibres having two different initial aspect ratios (L/D = 30 and 160) were analyzed. The processing-induced variation of fibre length was quantified by optical microscopy observations. Young modulus, stress at break, impact resistance and hardness values of starch-grafted-polypropylenes were remarkably improved by kenaf fibres. Moreover, creep tests have shown a noticeable enhancement of the creep stability of composites with fibres loading.