The investigation of the performance of different type of polymer matrix and fiber reinforced hybrid composites

In this study, different types of polymer matrix and fiber reinforced hybrid composites with high mechanical properties were aimed to be produced. In hybrid composites, orthophthalic, isophthalic, terephthalic unsaturated polyester resin and bisphenol-A based vinylester resin were used as matrix. Chopped E-type glass fiber was used as reinforcement. Experimental studies consisted of 3 stages. In the first step, two layers of orthophthalic, isophthalic and terephthalic polyester resin with epoxy based vinylester resin were produced and their interface compatibility were examined by SEM images. In the second stage, hybrid mixtures of different types of resins were prepared in 10 different combinations to improve their individual properties. Physical and mechanical tests and thermal analyzes of the samples were performed. The cured plates were cured for 1 hour at 50 ºC, 80 ºC and 110 ºC for a total of 3 hours. In the last stage; 5% , 10% and 20% by weight of E type glass fiber reinforced hybrid composites were produced for the same prepared resin mixtures. Mechanical tests were carried out on these samples. When SEM images were examined, it was observed that sufficient homogeneous adhesion was achieved at the interfaces of samples. It was concluded that the peak exotherm temperature values obtained in hybrid mixtures were obtained between 180 °C to 190 °C and all the mixtures were cured adequately when evaluated together with Barcol hardness values. As a result of the analysis, the highest tensile strength of all hybrid resin mixtures prepared for the orthophthalic-terephthalic-vinylester (OTV) mixture; which was found to be 11,1% higher than vinylester raw resin. The highest bending and charpy impact strength for orthophthalic-isophthalic-vinylester (OIV) resin; which was found to be 4,3% higher than vinylester and 23,9% higher than the orthophthalic raw resin. When the matrix resin hybridization was strengthened with fiber reinforcement, it has been determined that as the fiber ratio is increased, the mechanical properties are increased and the highest mechanical properties are obtained at 20% fiber ratio. When the HDT and FT-IR analyzes of the mixtures were examined, it was concluded that the required molecular adherences and cross-network structure were obtained in the mixtures and polymerization was achieved.