Synthesis of a novel benzoxazine‐containing benzoxazole structure and its high performance thermoset

A novel benzoxazine containing benzoxazole structures (Boz‐BOA) was synthesized and its thermoset P(Boz‐BOA)] was prepared. For comparison, another benzoxazine‐based 4,4′‐diamine diphenyl methane (Boz‐MDA) was also synthesized using a simplified procedure. The structure of Boz‐BOA and Boz‐MDA was confirmed by Fourier transform infrared (FTIR) and ¹H‐NMR. Using FTIR and differential scanning calorimetric scans method, the curing behavior of Boz‐BOA was probed, and the structure of P(Boz‐BOA) was addressed, which was similar to that of P(Boz‐MDA). Data of dynamic mechanical analysis showed that P(Boz‐BOA) exhibited a better modulus retention at high temperature than P(Boz‐MDA), which was attributed to benzoxazole structure restricting the mobility of chains, even at high temperature. P(Boz‐BOA) also exhibited high glass transition temperature (T_g), excellent thermal stability, and low coefficient of thermal expansion value at wide temperature range. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012