A Novel Imidazole-Core-Based Benzoxazine and Its Blends for High-Performance Applications

In the present work, a novel imidazole-core-based bisphenol (IBP) was synthesized and characterized. The IBP and formaldehyde were reacted separately with aniline and N,N-dimethylaminopropylamine (DMAPA) under appropriate conditions to obtain benzoxazines, which were characterized for their molecular structure and thermal behavior using different analytical methods. Both types of benzoxazines, imidazole core aniline-based benzoxazines (IBPA-Bz) and imidazole core-DMAPA-based benzoxazines (IBPD-Bz), possess better glass temperatures (T-g) and higher char yield's than conventional, benzoxazines (bisphenol-F-based benzoxazine (BPFb) and bispheriol-A-based behzoxazine (BPAb)). However, the curing temperature (T-p) of B3PD-Bz is lower than that of IBPA-Bz. The blending of IBPA-Bz with conventional benzoxazines (BPAb and BPFb), improved their thermal stability to an appreciable extent. Furthemore, the addition of bismaleimide cross-linkers (4,4'-diaminodiphenylsulfone- and 4,4'-diaminodiphenylmethane-basectbistnaleitnides) to the blends of IBPA-Bz and conventional benzoxazines hnproved the thermal behavior according to their nature and concentration. Moreover, the selected blends of benzoxazines were incorporated With 10% loadings of catalysts (4-hydroxyphenylmaleimide, 4-aminopheriol, and 4-hydrOxyacetophenone), and it was observed that Tp was reduced without significant variation in the thermal behavior, i.e., a reduction of more than 36 degrees C was noticed for both conventional benzoxazines. On the basis of the data obtained from the different studies, it is concluded that the blends of IBPA-Bz and conventional benzoxazines can be used in the form of sealants, encapsulants, adhesives, and matrixes in the fields of microelectronic and automobile applications for better performance with enhanced longevity.