Synthesis and characterization of novel nitrogen-phosphorus-containing poly(phthalazinone ether ketone)s

Abstract A series of novel polymers were synthesized by aromatic nucleophilic polycondensation of 2,2-Difluorobenzophenone (DFBP), with various ratios of 4-(4-hydroxyphenyl)phthalazin-1(2H)-one (HPPZ) to 10-(2,5-dihydroxyphenyl)-10-hydrogen-9-oxaze-0-phosphame-10-oxide (DHOPO). The chemical structures were identified by FTIR and 31P NMR. The results of TGA and DSC demonstrated an excellent thermal decomposition temperature, high Tg values, and high char yields. In addition, they displayed good solubility and can form uniform membranes in most common organic solvents. It may be ascribed to their synerfistic effect of the specially designed molecular structure stemming from nitrogen and phosphorus. These polymers should have potential applications in flame-retardant materials, composite materials, and insulating coatings.