Feedstock And Processing Effects On The Performance Of Natural Fiber Thermoset Composites

Natural fibre composites are seen as an attractive alternative to glass-fibre composites in a variety of applications due to their reduced cost, low density, and environmental benefits. Over the past decade, there has been significant research on the mechanical behaviour of various natural fibre systems, but there has been relatively few studies comparing the effect of feedstock and processing variables in the same experimental set. In this comprehensive study, the mechanical performance of various natural fibre thermoset composites is compared. The effect of fibre type, fibre processing and composite fabrication method were investigated. Mechanical testing results include tensile strength, tensile modulus, elongation and charpy impact. Results were compared to conventional glass-fibre composites as a baseline.Overall, the following conclusions were found. Random mat glass fibre composites were shown to have significantly higher strength, elongation and impact toughness relative to all natural fibre composites tested, while modulus values were more comparable. Compression molded (CM) laminates were found to perform better than those manufactured using hand lay-up (HL). This was predominantly due to better consolidation resulting in higher fibre volume fractions and lower air void content. The performance of resin transfer molded (RTM) versus compression molded (CM) laminates were found to depend on fibre type (glass versus natural). There was no appreciable differences in laminate properties between the different natural fibres samples tested (i.e. natural fibre type, length and non-woven mat manufacturing method did not show significant effects). This suggests that improvements in natural fibre processing and mat manufacturing methods will be required to achieve composites which perform as well as synthetic counterparts.