Investigation on Mechanical Properties of Bamboo-Plastic Composites by Alkali Treatment and Illustration via Scanning Electron Microscopy

The morphological properties, tensile and flexural strength of composite materials made of bamboo fibres and plastic were investigated. Bamboo-plastic composites (BPCs) were made from bamboo fibres, plastic, and urea formaldehyde (UF) resin to evaluate the effects on mechanical properties. Two different types of plastics, namely polypropylene (PP) and low-density polyethylene (LDPE) were used to make the composite fabrication. The bamboo fibres were extracted after soaking them in a sodium hydroxide (NaOH) for 2 days. UF was also used to improve the compatibility and adhesion between the fibres and the plastic. There are three parameters for the composition of bamboo fibres for the BPCs production, which are 30 wt%, 50 wt% and 70 wt%. The plastic, bamboo fibres and UF were mixed and poured into the mould. The samples were then hot-pressed to form a composite material. The preparations for the material tests were carried out in accordance with ASTM D638 for tensile strength testing and ASTM D790 for flexural strength testing. The result of the study shows that the composite material with 50 wt% bamboo fibre content has better mechanical properties. The highest tensile strength for the composite was 5.08 MPa for LBC 2 and 11.39 MPa for PBC 2. The highest flexural strength was found to be 45.96 MPa for LBC 2 and 127.18 MPa for PBC 2. It was found that PP has higher tensile and flexural strength compared to LDPE. Observation of morphological properties shows voids, fibre breakage and weak adhesion of fibre and plastic. This study has shown that the BPC composites of PP and bamboo fibres can be used as a potential raw material in the composite industry.