Study on Direct Reactive Compatibilization of HDPE/Wood-Flour Composites

Reactive compatibilization between high-density polyethylene(HDPE) and wood-flour was achieved via direct reactive extrusion of maleic anhydride(MAH), initiator, HDPE and wood-flour. Impact rupture surface of the composites was observed by scanning electron microscope(SEM), and its load deformation temperature(HDT) and mechanical properties were tested. Effect of MAH dosage, initiator activity and extrusion temperature on the reactive compatibilization was analysed. The result indicated that the anchoring strength of interface in the composites was obviously strengthened and its HDT, tensile strength, flexural strength, notched impact strength and elongation at break were distinctly improved due to the addition of MAH and dicumyl peroxide(DCP). When the composites were extruded at 180°C, the peak values of its HDT, tensile strength, flexural strength, elongation at break and notched impact strength respectively were 79°C, 34Mpa, 36Mpa, 30% and 10KJ.m-2, which respectively increased by 10°C, 62%, 33%, 200% and 150% than that of the composites without reactive compatibilization, and when the composites were extruded at 200°C, the peak values of its HDT, tensile strength, flexural strength, elongation at break and notched impact strength respectively were 78°C, 34Mpa, 36Mpa, 24% and 8KJ.m-2, which respectively increased by 12°C, 55%, 33%, 200% and 100% than that of the composites without reactive compatibilization. In the case of DCP and MAH as compatibilizer, there was an optimum dosage of MAH. The optimum dosage was shifted forward as extrusion temperature increased.