Reinforced Polyester Hybrid Composites Research Articles

Elastic properties, notched strength and fracture criterion in untreated woven jute–glass fabric reinforced polyester hybrid composites

The elastic properties and notch sensitivity of untreated woven jute and jute–glass fabric reinforced polyester hybrid composites has been investigated analytically and experimentally. Elastic properties were predicted by using the rule of hybrid mixture and classical lamination theory (CLT). Analytical investigation on notch sensitivity was carried out by using well known point stress criterion (PSC) and modified PSC criterion. Experimentally, elastic properties and notch sensitivity were determined by conducting tension test on specimens. The objective of the investigation is to determine the extent of applicability of stress fracture criteria that were developed for synthetic fibre composites, to natural fibre and hybrid composites. The characteristic dimension of PSC criteria was found to increase slightly with the increase in the hole size for all the types of laminates considered. However, modified PSC model has resulted in excellent agreement between the experimental and predicted values. The effect of hybridization of glass fibre with jute fibre as well the effect of hole size on the notch sensitivity of the composites under consideration is discussed.

Studies on mechanical performance of biofibre/glass reinforced polyester hybrid composites

The degree of mechanical reinforcement that could be obtained by the introduction of glass fibres in biofibre (pineapple leaf fibre/sisal fibre) reinforced polyester composites has been assessed experimentally. Addition of relatively small amount of glass fibre to the pineapple leaf fibre and sisal fibre-reinforced polyester matrix enhanced the mechanical properties of the resulting hybrid composites. Different chemically modified sisal fibres have been used in addition to glass fibers as reinforcements in polyester matrix to enhance the mechanical properties of the resulting hybrid composites. The surface modification of sisal fibres such as alkali treatment produced optimum tensile and impact strengths, while cyanoethylation resulted in the maximum increase in flexural strength of the hybrid composites. It has been observed that water uptakes of hybrid composites are less than that of unhybridized composites. Scanning electron microscopic studies have been carried out to study the fibre-matrix adhesion.