Biobased dual-cure thiol-ene benzoxazine resins for high-performance polymer dielectrics

In the present study, two magnolol based main chain benzoxazine polymers (MCBPs) are designed, synthesized and formulated into thiol-ene resins to develop high-performance polymer dielectrics. Initially, thermoset films, Mag-M-4SH-80 Mag-E-4SH-80, obtained respectively using click chemistry. Being post cured via progressive temperature stage, Mag-M/E-4SH-80 performs complete ring opening polymerization forms dual-cure polybenzoxazine (PBZ) products with excellent thermal mechanical performances such as a high Tg of 236 °C flexure modulus 2.5 GPa. Moreover, thiol component resin introduces numerous dipoles resultant networks, resulting in promising dielectric at both room elevated temperature. For instance, film demonstrates superior energy density (Ue) 7.0 J/cm3@25 °C, which is among top reported thermosets having same efficiency, Mag-M-4SH-150 reveals Ue 1.1 J/cm3@150 significantly higher than values great number commercial heat resistant polymers. Herein, our findings not only expand library but also their potentials flexible dielectrics for storage first time, thus advance functionality capability materials modern electronics.