Synthesis of all aromatic poly(thioether-ketone)s, sulfur-containing high performance polymers with high solubility

Novel aromatic poly(thioether-ketone)s (PTEKs) bearing the 2,6-dimethyl-1,5 -naphthylene unit were synthesized by the polycondensation of aromatic diha loketones and aromatic dithiols in the presence of K2CO3 High molecular wei ght (Mn similar to 65 000, Mw similar to 350 000) PTEKs were obtained in qu antitative yields. The molecular weight and yield of PTEK obtained from dic hloroketone and dithiol were much higher than those of the corresponding po ly(ether-ketone) obtained from dichloroketone and biphenol. The use of the fluoroketone as a monomer did not increase the Mn of PTEK. The effect of re action conditions on the yield and the molecular weight of PTEKs was invest igated. The phase-transfer-catalysed polycondensation and the polycondensat ion using masked dithiol and dichloroketone were also investigated. The PTE Ks prepared have high solubility in ordinary organic solvents. Flexible, tr ansparent, and strong cast films were prepared. The PTEKs had high glass tr ansition temperatures (PTEK-1, 245 degreesC and PTEK-2, 215 degreesC) and 5 % weight loss temperatures (PTEK-1, 435 degreesC and PTEK-2, 436 degreesC).