Rahul Kumar

Laminates made from carbon‐ and glass‐fiber‐reinforced polymers (FRP) possess excellent specific strength and stiffness, making them suitable for structural applications. However, the high cost of virgin carbon fibers has increased interest in using recycled or chopped carbon fibers (CCFs) recovered from waste CFRP. In the present study, both untreated and silane‐functionalized CCFs were incorporated into an epoxy matrix at loadings of 0.5, 1.0, and 1.5 wt%, and used to fabricate hybrid glass fiber‐reinforced polymer (GFRP) laminates. Silane‐treated CCFs improved laminate performance by enhancing compatibility between the CCF and the epoxy, promoting stress transfer at the interface, bridging and deflecting microcracks, and suppressing interlaminar delamination. At 0.5 wt% S‐CCF, reinforcement was effective due to relatively uniform dispersion, whereas higher CCF loadings could form CCF‐rich regions and local stress concentrations, reducing strength and toughness. The 0.5 wt% S‐CCF laminates showed the best performance. Compared with control GFRP, tensile strength, tensile modulus, and toughness increased by about 27%, 4%, and 39%, respectively, while flexural strength and short‐beam shear strength improved by 38% and 13%. These results demonstrate that surface‐modified recycled CCFs can enhance mechanical performance and delamination resistance in a sustainable and potentially cost‐effective manner.

The present state of the art of the bamboo fibres and their reinforcement in polymer matrices is concentrated on bamboo fibre reinforced thermoset and thermoplastic polymer composite material. The bamboo fibre is selected on the basis of sources of origin, growth rate, and availability as agricultural waste, excellent specific mechanical properties and application. An overview of the developments made in the area of bamboo fibre reinforced composites is presented in terms of their mechanical properties, manufacturing procedures and applications. Effect of Fibre orientation, its length, reinforcing concentration, dispersion, aspect ratio, selection and chemistry of matrix and surface modification of fibres on the characteristics of composite has been discussed in resilient manner. Several critical concerns and recommendations for further improvement of composite properties and future work related to bamboo fibres are deliberated. The present work satisfies the need for a short critical review, consolidating the highly utilized agriculture by-products originating from the stem part of the plant fibres.

Nowadays, the research and engineering attention stimulated towards development of environmentally gentle materials to satisfy the energy needs of the society through renewable resources. The growing cognizance in the production and consumption of renewable energy for civilization necessities has directed towards the growth in the wind energy utilization. The wind energy is a leading renewable and sustainable energy resource and key answer to the global energy problem. The rotor blades of wind turbines are its integral parts and traditional materials used for blade manufacturing are carbon or glass fibre reinforced polymer composites owing to their low density and high strength to stiffness ratio. But the non renewability and adverse environmental effect during their processing and disposal forced the researchers to look out for some biodegradable and light weight natural plant fibres for reinforcement in polymeric resin to produce required polymer composites. In the present work, application of bio filler based epoxy composite is proposed to be used as wind turbine rotor blades.