Photoinduced polymerization of acrylates with polybenzoxazine macroinitiators for polyacrylate/polybenzoxazine networks

In this study, we synthesized benzophenone-based main chain polybenzoxazine (BP-PBz) as a type II macroinitiator and this initiator was used to synthesize acrylate-based polybenzoxazine copolymers. BP-PBz effectively initiated the polymerization of methyl methacrylate (MMA) and poly(ethylene glycol) diacrylate (PEGDA), resulting in either polybenzoxazine-grafted-poly(MMA) or crosslinked polybenzoxazine networks. Polymerizations of the formulations were performed upon photolysis at ca. 300 nm. The obtained polymers retained their oxazine functionality and subsequent thermal curing was applied successfully at relatively lower temperatures than conventional benzoxazines. The precursors are shown to have a dual curable character that could be beneficial for deep curing purposes. The synthesized polymers were characterized using various techniques, including nuclear magnetic resonance (NMR), Fourier-transform infrared (FT-IR), ultraviolet-visible (UV–Vis) spectroscopy, and thermogravimetric analysis (TGA), along with differential scanning calorimetry (DSC).