Patent ID: 6482946
Filing Date: 2002-11-19
Classification: C07D,C08G

Abstract:
A method to make a high char yield polybenzoxazine comprising,forming a mixture having (i) a benzoxazine compound of the formula â€ƒwhere R4 is (a) a divalent radical that is aliphatic, aromatic or combination thereof that contains from 1 to 35 carbon atoms with up to 5 atoms selected from oxygen, nitrogen, sulfur, phosphorous, halogen or combinations thereof; (b) a single bond or (c) S, S2, SO, SO2, O or CO and R5 is H, unsubstituted alkyl having one to 24 carbon atoms, an unsubstituted aryl having 6 to 24 carbon atoms, or R5 has a formula selected from the group consisting of: â€ƒwhere R1 is H, OH or an unsubstituted alkyl of 1 to 6 carbons; (ii) a furan compound selected from the group consisting of furan, furfural, furoin, furfuryl alcohol, furil, dimethyl 3,4-furandicarboxylate, a furan having a formula selected from the group consisting of, â€ƒwhere X is and a furan having the formula, â€ƒwhere R6 is a single bond or a 1 to 5 carbon alkylene; (iii) a benzoxazine-furan compound having a formula of, â€ƒwhere R3 is a single bond or an alkylene having one to 6 carbon atoms and R7 is H or unsubstituted alkyl having from 1-6 carbon atoms; or (iv) combinations thereof, such that the mixture has a furan ring to benzoxazine ring ratio of about 0.001 to about 10 and heating the mixture for a sufficient time to form the polybenzoxazine.