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The prime importance of this work is that to compare the influence of hygrothermal analysis on the physical properties of different variant of interpenetrating polymer network (IPN) blend reinforced with E-Glass/Carbon and combination of both (hybrid) fibers. In this study, combinations of epoxy (EP)/polyurethane (PU), vinyl ester (VER)/polyurethane (PU), and epoxy (EP)/vinyl ester (VER) have been taken as the matrix material (IPN) to reinforce the glass, carbon, and combination of both fibers. Moreover, prepared specimens are subjected with boiling water immersion test by maintaining the temperature of 45°C, 55°C, and 65°C in order to thoroughly understand the influence of moisture absorption and temperature in their physical attribution as per ASTM standards. Besides, to better understand the thermal stability and compatibility, thermal-gravimetric (TGA) analysis and burn-off test were conducted as well. During this study, it was found that, combination of VER/PU possesses the high moisture absorption resistance amongst all variants (0.725% for 45°C, 0.854% for 55°C, 1.234 for 65°C). Similarly, epoxy/vinyl ester reinforced glass fiber IPN laminate (EVG) has shown notable TGA value as 418.6°C, as well burn-off test also shown that hybrid IPN composites have better wettability (less void presence) than all other laminates (EPGC-0.9%, VPGC-0.89%, EVGC-0.92%). Further, losses of physical strengths have been noticed on all specimens upon subjection on hygrothermal environment irrespective of IPN blend and fiber constituents.

In this work, various proportionate (0%, 1%, 3% 5% & 7%) of titanium di-oxide nano-filler was utilized as particulate matter along with the sisal/jute fiber reinforcement, in the view to increase the physical properties of the composite materials. Beside, as matrix material the mixture of Epoxy (E) and Polyurethane (PE) was chosen with the proportionate of 70 and 30 wt.% respectively, in order to extract the specific qualities of both the matrices to achieve the interpenetrating polymer networks (IPNs). Moreover, to exactly find out the thermo-mechanical characteristics of the sisal/jute fiber reinforced IPN composites, tests like thermo-gravimetric analysis (TGA), tensile, flexural, Impact, short beam strength and water absorption tests were carried out as per standards. It was found that, incorporation of 5% of TiO 2 , increases the mechanical properties such as tensile, flexural, impact and short beam strength. Similarly, incorporation of TiO 2 into IPN matrix enhances the thermal stability and water absorption resistance. All the obtained values of various filler weight % of TiO 2 were compared with each other against with and without particulate incorporated IPN laminate in the purpose of using the same in construction industries.

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In high speed machining, performance is generally influenced by the dynamic behaviour of the machine tool structures. The machine tool structure is required to be rigid in order to remove the undesirable vibration and to improve the work piece quality. The most conventional material used in machine tool structure is cast iron which has both stiffness and dynamic characteristics to perform at varying speeds. The objective of this work is to improve damping capacity of vertical machining centre column. The damping capacity of column can be increased further by using passive damping method of ball packing. Damping capacity is a crucial factor which makes the dissipation of vibration happens at faster rate. As compared with cast iron established studies shows that epoxy granite a composite material improves damping capacity. Epoxy granite though could be a good choice for improving the machine tool performance at high speeds but is poor in static stiffness compared to cast iron. In this investigation it was observed that, the static stiffness of epoxy granite composite vertical machining centre column could be increased by using steel reinforcements. The final results reveal that, steel balls with epoxy granite provide faster dissipation time of 15ms at 70% packing ratio as compared to glass balls that showed dissipation time of 35ms. Also it was seen that, the steel balls offer the better damping capacity at optimum packing ratio of 50% mainly due to its specific gravity and mass of the balls.