Abstract
In this study, the effects of adding different coupling agents, e.g. maleic anhydride-grafted polyethylene (MAPE), silane (3-aminopropyltrimethoxy silane) (silane 1189) and isocyanate (hexamethylenediisocyanate) (HDI) on mechanical and morphological properties of composite samples of high density polyethylene/old corrugated container fibres (HDPE/OCC) were studied. The amounts of OCC fibre and coupling agents used were 30% and 2% of dry composite weight, respectively. Mixing of materials was carried out by a two-screw counter extruder and samples were prepared by injection moulding. In order to compare the results of the use of mixture coupling agents, their effects were studied independently, as well. Mechanical properties of prepared composite samples containing coupling agents were measured and the results were compared with those of pure high density polyethylene and those of composite samples without coupling agent. The measured mechanical properties showed that maximum values of tensile and flexural strengths and tensile and flexural modulus could only be obtained in composites containing a mixture of silane1189 and MAPE coupling agents. It was also observed that the Izod impact strength values of composites with coupling agents increased significantly.
SEM micrographs of failure surfaces of samples showed that the best homogeneity of composites and bonding between OCC fibres and polymer matrix were obtained for the sample containing 1 wt.% silane and 1 wt.% MAPE.