Benzoxazines are bicyclic compounds formed by the ring fusion of a benzene ring with an oxazine.
Polybenzoxazines are a class of polymers formed by the reaction of phenols,
formaldehyde, and primary amines which on heating to ~200 °C (~400 °F) polymerise to produce polybenzoxazine networks. The resulting high molecular weight
thermoset polymer matrix composites are used where enhanced mechanical performance, flame and fire resistance compared to epoxy and phenolic resins is required. == Physical properties ==