The effect of 3-hydroxyphenylboronic acid on thermal characteristics of polybenzoxazine based on phenol and 4-aminomethylbenzoate

In this study, a polybenzoxazine, (PPab) based on phenol and 4-aminomethyl benzoate and its composites containing various amounts of 3-hydroxyphenylboronic acid, (HB) were prepared by stepwise curing. It has been found that thermal properties of composites were improved as the amount of HB introduced was increased. The improvements in thermal characteristics were associated with condensation reactions of hydroxyl groups of polybenzoxazine and ester groups on the aniline linkages yielding a highly cross-linked structure. In addition, application of direct pyrolysis mass spectrometry, DP-MS, technique supplied information pointing out generation of a boroxine network by self-condensation reactions of B-OH groups.