Preparation of Bio-Based Polybenzoxazine/Pyrogallol/Polyhedral Oligomeric Silsesquioxane Nanocomposites: Low Dielectric Constant and Low Curing Temperature

In this work, a bio-based benzoxazine monomer (C-s) is synthesized from cardanol, stearylamine, and paraformaldehyde through solvent-free method. Pyrogallol is used as a curing catalyst for the ring-opening polymerization of benzoxazine. Differential scanning calorimeter (DSC) results reveal that doping with pyrogallol reduces the exothermic peak temperature ( T p ) of C-s from 256 to 174 °C. The polybenzoxazine/pyrogallol/polyhedral oligomeric silsesquioxane (PC-s/py/POSS) nanocomposites are prepared via thermal curing. The doping of aminopropyl isobutyl POSS (POSS-NH 2 ) can reduce the dielectric constant of polybenzoxazine. The dielectric constant of PC-s/py/POSS is 2.64 at 1 MHz when the doping amount of POSS-NH 2 is 10 wt%. The results of thermogravimetric analysis (TGA) and water absorption test indicate that the PC-s/py/POSS nanocomposites possess good thermal stability and water resistance. In summary, the PC-s/py/POSS nanocomposites with low curing temperature and low dielectric constant are expected to be applied to the low dielectric materials for microelectronic applications.