New thermosetting resin from bisphenol A-based benzoxazine and bisoxazoline

Bisphenol A-based benzoxazine was prepared from bisphenol A, formaline, and aniline. Curing reaction of bisphenol A-based benzoxazine with bisoxazoline and the properties of the cured resin were investigated. Consequently, using triphenylphosphite as a catalyst, for the first time the ring-opening reaction of benzoxazine ring occurred at 170°C, and then the phenolic hydroxyl group generated by the ring-opening reaction of the benzoxazine ring reacted with the oxazoline ring at 200°C. The melt viscosity of the molding compound was kept 0.1–1 Pa · s at 140°C even after 1.5 h, and increased rapidly at 180°C. It was realized that the molding compound showed good flowability below 140°C, curing reaction proceeded above 180°C rapidly. The cured resin from bisphenol A-based benzoxazine and bisoxazoline showed good heat resistance, water resistance, electrical insulation, and mechanical properties, compared with the cured resin from bisphenol A-type novolac and bisoxazoline.