Hybrid polymer matrix development using cashew nut shell liquid as an additive into epoxy resin

ABSTRACT The maximal exploitation of naturally existing resources for the synthesis of polymers can be an apparent choice when environmental and economic concerns are taken into account in enterprises producing new generations of hybrid polymers. Cashew Nut Shell Liquid (CNSL) is one of the most promising alternatives for incorporating it as an additive into epoxy resin due to the availability of similar functional groups in both CNSL and epoxy for an identical or even superior set of performance characteristics. A novel hybrid polymer cast (HPC) has been developed by mixing different weight percentages of epoxy and CNSL along with 2.5 wt.% of Al particles as reinforcement and amine-based hardener. The mechanical and thermal behaviors have been examined using Scanning Electron Microscope, Thermogravimetric analysis, Universal Testing Machine, and Fourier Transform Infrared Spectroscopy (FTIR). The availability of the functional groups of CNSL and epoxy has been confirmed using SEM-EDS and FTIR. Mechanical characterization of the HPC with 30 wt.% CNSL reveals higher flexural strength, strain rate, and impact strength than other HPCs. When adding Al particles, the brittle behavior decreases due to the enhancement of bonding. Thermal analysis of HPC with 40 wt.% of CNSL exhibits lower residual mass without affecting its thermal stability.