Mechanical properties of high density polyethylene matrix composites reinforced with chitosan particles

Abstract

High Density Polyethylene (HDPE) matrix composites reinforced with chitosan particles were developed by compression moulding technique. Chitosan particles extracted from deep sea squid with 90% deacetylation, bulk density of 0.3 g/cm3 and particle size of 90 μm were used as reinforcement. HDPE and various weight fractions (2, 4, 6, 8 and 10 wt%) of chitosan particles were melt-compounded in a single screw laboratory extruder with rotational speed of 50 rpm and temperatures of 190–220 °C. The blends were then moulded into different test specimens using carver laboratory press at a temperature of 230 °C for 12 min under applied pressure of 0.2 kPa. The mechanical properties (flexural, tensile and impact) of the developed composites were studied. The results showed that there were improvements in the mechanical properties of the composites. The optimal values for the tensile strength and tensile modulus of the composites were observed at 2 wt% chitosan particles reinforcement with values of 23.14 MPa and 828.38 MPa respectively while that of flexural strength and flexural modulus were noticed at 4 wt% with values of 83.90 MPa and 1690 MPa respectively. The impact strength of the composites increased linearly from 2 to 10 wt% Chitosan particles reinforcement with an optimum value of 229.20 KJ/m2. The scanning electron microscope (SEM) examination of the composites revealed that there were homogeneous particles dispersion at lower weight fractions (2–6 wt%) while particles agglomerations were noticed on the SEM images at higher weight fractions (8–10 wt%).