Abstract
Furan-containing benzoxazine monomers, 3-furfuryl-3,4-dihydro-2H-l, 3benzoxazine (P-FBz) and bis(3-furfuryl-3,4-dihydro-2H-l,3-benzoxazinyl) isopropane (BPA-FBz), were prepared using furfurylamine as a raw material. The chemical structures of P-FBz and BPA-FBz were characterized with FTIR, 1 H NMR, elemental analysis, and mass spectrometry. Formation of furfurylamine Mannich bridge networks in the polymerizations of P-FBz and BPA-FBz increased the cross-linking densities and thermal stability of the resulting polybenzoxazines. P-FBz- and BPA-FBzbased polymers also exhibited high glass transition temperatures above 300°C, high char yields, and low flammability with limited oxygen index values of 31. The dielectric (D k = 3.21-3.39) and mechanical properties (high storage modulus of 3.03.9 GPa and low coefficient of thermal expansion of 37.7-45.4 ppm) of the P-FBzand BPA-FBz-based polymers were superior or comparable tp other polybenzoxazines. © 2005 Wiley Periodicals, Inc.