Triphenylphosphine oxide-based bismaleimide and poly(bismaleimide): Synthesis, characterization, and properties

A novel phosphorus-containing bismaleimide, 3,3 ' -bis(maleimidophenyl)-phe nylphosphine oxide (BMPPPO), was synthesized from triphenylphosphine oxide. This bismaleimide exhibited good solubility in common organic solvents, su ch as methylethylketone, methylisobutylketone, dichloromethane, chloroform, tetrahydrofuran, acetone, methanol, ethanol, and hot toluene. A low meltin g point (T-m = 148 degreesC), a relatively low polymerization temperature ( T-p = 214 degreesC), and a wide processing window (T-p - T-m = 66 degreesC) were also obtained for BMPPPO. This implies better processing capability. Ln contrast to most known phosphorus-containing polymers, the incorporation of BMPPPO into poly(bismaleimide) enhanced the polymer glass-transition te mperature. Thermal stability at temperatures over 550 degreesC and char yie lds in the high-temperature region over 700 degreesC were also improved. As a result, the flame-retardant properties of the poly(bismaleimide)s were i mproved. (C) 2001 John Wiley & Sons. Inc. J Polym Sci A: Polym m Chem 39: 1 716-1725, 2001.