Environmentally friendly natural fibre composites with Qld. based vegetable oils

Abstract

In modern times there has been a growing focus towards environmental awareness and sustainability which has entered the fibre composite industry. This attitude has seen an emergence in the occurrence of environmentally friendly, sustainable materials. Traditional synthetic composites are predominately constructed from petro-chemical based resins and synthetic fibres. These traditional petro-chemical based composites have benefited society in many different ways. Recently there has been increasing concerns over the finite nature and the unsustainably of these resources. A genuine concern is the increase of costs as the availability of the resource reduces. There is a requirement to find a sustainable replacement material for use in industry, and this is where natural fibre composites are being positioned. This project has compared natural fibre composites made from epoxidized vegetable oils and hemp fibres with traditional glass fibre composites through the investigation of mechanical and thermal properties. An understanding of the benefits of making the composites has been gained throughout this project. Traditional glass fibre composites were manufactured using the hand layup technique and the microstructure, thermal and mechanical properties were characterised through flexural tests, impact tests, DMA and microscopic analysis. Natural fibre composites were manufactured from different types of hemp fibre (short bleached and raw long)and different types and quantities of EVO using randomly orientated short hemp fibres and also unidirectional hand laid hemp fibres. The effects of fibre content and alkali treatment of the hemp fibre were analysed through mechanical, thermal and microscopic analysis. Natural fibre composites were compared with traditional glass fibre composites through mechanical, thermal and microscopic analysis. This study has confirmed the ability of natural fibres and plant-oil based resins as feasible resources from which to manufacture fibre composites. Improvements were realised through the use of alkali treatment of the fibres. In terms of cost and specific material properties, natural composites represent an alternative to traditional synthetic fibre composites in certain applications