Structure, thermal, hydrophobic, and dielectric properties of Bermuda grass ash bio-silica, SBA-15, and rGO-reinforced bisphenol-BA-based polybenzoxazine composites

The present work deals with the development of bisphenol-BA based benzoxazines and to study their behavior toward utilization for thermal, high-dielectric, low-dielectric, and anti-corrosion applications. A new type of bifunctional benzoxazine resins were synthesized using bisphenol-BA with different types of amines and characterized using FTIR, H-1-NMR spectra, DSC, and TGA techniques. In the present study, thermally stable bisphenol-BA with trifluoromethylaniline benzoxazine (BBA-tfma) and bisphenol-BA with furfurylamine benzoxazine (BBA-ffa) were selected as matrices for the preparation of composites with SBA-15, bio-silica (from Bermuda grass) and reduced graphene oxide. The results indicated that the poly(BBA-tfma) with 5 wt% SBA-15 composites and poly(BBA-ffa) with 10 wt% bio-silica composites showed the lowest dielectric constant value of 1.71 and 1.87, respectively. While in contrast, the 5 wt% of reduced graphene oxide (rGO) reinforced poly(BBA-tfma) exhibits highest value of dielectric constant (k = 8.49). Results from corrosion studies ascertain that the bisphenol-BA with aminoethoxyethanol benzoxazine, that is, poly(BBA-aee) possess better mild steel corrosion protection behavior than that of other benzoxazines. Data resulting from different studies indicate that the bisphenol-BA-based benzoxazines and their composites can be effectively used for different industrial applications.