Studies on Twill Weave Carbon Incorporated Bio‐Based Epoxy Blended Polybenzoxazine Composite

Abstract In our current study bio‐based guiacol, thymol, triamine, and paraformaldehyde were used to synthesize benzoxazines. The molecular structures of benzoxazines were characterized by attenuated total reflectance‐FTIR, 1 HNMR, and 13 CNMR spectroscopic techniques. The synthesized benzoxazines were successfully polymerized to hyperbranched polybenzoxazine through thermal curing process which were confirmed through differential scanning calorimeter (DSC). Biobased phenol derived polybenzoxazines thermosets demonstrated a good thermal stability which was indicated by higher thermal degradation around 550‐575 °C. The obtained polybenzoxazines were drawn in to composite sheets by cross‐linking with epoxy resin (LY556) and reinforced with 15 wt% twill weave carbon fiber. The composite sheets of benzoxazine were tested on its wettability, mechanical property, and the dielectric nature. The contact angle measurement of polybenzoxazine based composite sheets confirmed the good hydrophobic properties in the range of 104°–108°. Composite with 2 wt% benzoxazine exhibited highest flexural stress of 3426 MPa and modulus of 43.5 GPa. The SEM image was recorded for the polybenzoxazine compoiste where th study reveals ehnaced interfacial adhesion between the polmer matrix and the resin.