High performance thermosets from a curable Diels-Alder polymer possessing benzoxazine groups in the main chain

Abstract

A high-molecular-weight polymer (PBz) possessing reactive benzoxazine groups in the main chain was prepared through the Diels-Alder reaction using bis(3-furfuryl-3,4-dihydro-2H-1,3-benzoxazinyl)isopropane (BPA-FBz) and bismaleimide (BMI) as monomers. The chemical structure of PBz is characterized with FTIR and 1H NMR. The polymer PBz was further thermally reacted with a high performance polymer (PBz-R) through the ring-opening addition reaction of benzoxazine groups and the addition reaction of maleimide groups. PBz-R exhibit a high glass transition temperature of 242 °C, good thermal stability, high flame retardancy, high mechanical strength, and great flexibility. Another crosslinked polymer (PBz-BR) curing from the mixture of BPA-FBz and BMI was also prepared. The properties of PBz-BR are also attractive but, however, not as good as what observed with PBz-R. © 2008 Wiley Periodicals, Inc.