STUDY ON TENSILE AND FLEXURAL PROPERTIES OF RECYCLED HIGH DENSITY POLYETHELENE/SAWDUST COMPOSITES

Plastic lumber is a wood plastic composite and usually made from recycled
material. It is composed of recycled High Density Polyethylene (r-HDPE) and
wood waste known as saw dust. The goal for this project is to evaluate the tensile
and flexural properties of r-HDPE/sawdust composites with various compositions.
The sawdust was ranging from 0 wt% to 50 wt%. Sawdust is commonly available
at furniture factories whereas r-HDPE was collected from milk and yoghurt bottles.
Twin-screw extruder and hot press compression moulding machines were used to
produce this polymer composite. Study of the mechanical properties of the loading
sawdust content showed that tensile strength of the composites is decreased with
increasing of sawdust content. The best tensile strength was achieved with I 0 wt %
of sawdust, which translated to reductions of 14.3% compared to pure r-HDPE.
For flexural strength and modulus, the performance is increased by increasing of
sawdust content. The maximum flexural strength and modulus were obtained with
40 wt% of sawdust content, which were 46.0% and 58.9% improvement. Scanning
electron microscopy (SEM) images of the fractured surfaces from tensile testing
had been done to investigate the interfacial bonding between sawdust and r-HDPE
matrix