Novel phosphorous–nitrogen containing poly(aryl ether ketone)s: synthesis, characterization, and thermal properties

Abstract

A series of high-molecular-weight poly(aryl ether ketone)s (PAEKs) with phosphorus and nitrogen on the side and main chains were synthesized by a nucleophilic substitution polycondensation of 1,2-dihydro-4-(4-hydroxyphenyl)-phthalazin-1(2H)-one (DHPZ) with 1,1′-bis(4-hydroxyphenyl)-metheylene-bispheny-1-oxophosphine oxide (DOPO-PhOH) and 4, 4′-difluorobenzophenone (DFBP) at various molar ratios. The structures of the PAEKs were characterized by means of Fourier transform infrared spectra, nuclear magnetic resonance spectroscopy (1H NMR, 31P NMR), and elemental analysis. All these polymers are amorphous and soluble in common organic solvents such as dimethylacetamide (DMAc), chloroform, and tetrahydrofuran (THF) at room temperature. The thermal stability and degradation behavior of the synthesized PAEKs were measured with thermal gravimetric analysis measurements. The influence of nitrogen and phosphorus containing monomer ratio on their thermal stability was investigated by adjusting the proportion of the DHPZ and DOPO-PhOH from 0/10 to 7/3. The glass transition temperatures (T g’s) of the polymers were obtained with differential scanning calorimeter measurements. All results suggest that these polymers have high glass transition temperatures and good thermal stabilities.