Blends of 4,4′-diaminodiphenyl methane-based benzoxazine and polysulfone: morphologies and properties

Polysulfone (PSU) was used to modify 4,4′-diaminodiphenyl methane-based benzoxazine (BZ-m) through reaction-induced phase separation. The curing behaviors and kinetics were investigated using differential scanning calorimeter (DSC), and the results showed that the activation energies of PSU/BZ-m mixtures polymerization increased as the amount of PSU increased. Dynamic mechanical analysis (DMA), temperature-modulated differential scanning calorimeter (TMDSC) and scanning electron microscopy (SEM) were applied to study the phase structures of PSU/BZ-m blends. Four different morphologies were obtained by increasing the proportion of PSU in this work. These blends displayed different properties due to the different phase morphologies. The blend with bicontinuous phase structure exhibited excellent mechanical properties and thermal properties, and we believe that these blends can be applied as matrices for high-performance composites.