Thermo-mechanical properties of epoxidized hemp oil-based bioresins and biocomposites

Novel epoxidized hemp oil-based biocomposites containing jute fibre reinforcement were produced at the Centre of Excellence in Engineered Fibre Composites (CEEFC) owing to the need to develop new types of biobased materials. Mechanical properties (tensile, flexural, Charpy impact and interlaminar shear), thermo-mechanical properties (glass transition temperature, storage modulus and crosslink density) and moisture-absorption properties (saturation moisture level and diffusion coefficient) were investigated and compared with samples containing commercially produced epoxidized soybean oil and a synthetic bisphenol A diglycidyl ether-based epoxy control, R246TX cured with a blend of triethylenetetramine and isophorone diamine. Scanning electron microscopy was also performed to investigate the fibre-matrix interface. Epoxidized hemp oil-based samples were found to have marginally superior mechanical, dynamic mechanical and similar water-absorption properties in comparison to samples made with epoxidized soybean oil bioresin; however, both sample types were limited to bioresin concentrations below 30%. Synthetic epoxy-based samples exhibited the highest mechanical, dynamic mechanical and lowest water-absorption properties of all investigated samples. This study has also determined that epoxidized hemp oil-based bioresins when applied to jute fibre-reinforced biocomposites can compete with commercially produced epoxidized soybean oil in biocomposite applications

Technology and development of self-reinforced polymer composites

In recent years there has been an increasing amount of interest, both commercially and scientifically, in the emerging field of "self-reinforced polymer composites". These materials, which are sometimes also referred to as "single polymer composites", or "all-polymer composites", were first conceived in the 1970s, and are now beginning to appear in a range of commercial products. While high mechanical performance polymer fibres or tapes are an obvious precursor for composite development, various different technologies have been developed to consolidate these into two- or three-dimensional structures. This paper presents a review of the various processing techniques that have been reported in the literature for the manufacture of self-reinforced polymer composites from fibres or tapes of different polymers, and so exploit the fibre or tape performance in a commercial material or product