Ultra violet curing bio-fibre composites

Research was carried out to study the physical and mechanical properties of value added bio-fibre composites made by employing environmentally benevolent ultra violet (UV) curing technique. Standard mercury UV lamp was used for the investigation. Unsaturated polyester resin along with bisacylphosphine oxide was usedas polymer matrix. Rubberwood fibre (TMP fibres) residues, a waste and unutilized fibre from one of the medium density fibre board (MDF) plants, were used as the reinforcement fibres. Un-delignified TMP fibre mats could not be impregnated due to its high bulk factor. Improper cure of the composites was also expected due to the presences of lignin in the fibres. To overcome this problem and to enhance the interfacial adhesion between the matrix and fibre, anthraquinone-kraft (AQ-kraft) pulping known for its efficiency in the removal of lignin and for producing high strength fibre was adopted. Since the operating variables of pulping process control the ultimate strength of the fibre reinforcement, Response Surface Methodology (RSM) was employed to investigate the effect of the following pulping parameters (i) active alkali (ii) sulfidity (iii) temperature and (iv) time of cooking on the responses such as mechanical properties of composites, degree of cure and water absorption. The optimum conditions for AQ-kraft pulping are 17.0 % active alkali, 27.0 % sulfidity, 162°C pulping temperature and 95 minutes of pulping time. The mechanical properties of AQ-kraft pulped fibre composites showed properties superior to TMP fibre composites. This was due to better mechanical interlocking between the fibres and the grafted unsaturated polyester in AQ-kraft pulped fibre composites. Besides that, the gel content and resistance towards water were also better in AQ-kraft pulped fibre composites. Scanning electron microscopy (SEM) studies were carried out on both the type of fibre composites to confirm above findings. In references to the above studies similar type of research can be carried out on palm oil empty fruit bunches (EFB), which are available abundantly and unutilized.