Synthesis and characterization of poly(aryl ether ether ketone ketone)/poly(aryl ether sulfone ether ketone ketone) containing bis(o-methyl) moiety

Poly(aryl ether ether ketone ketone) (PEEKK) is a kind important high-performance polymer due to its excellent thermal stability and other outstanding properties which is similar to PEEK and PEKK. However, the PEEKK's insolubility in common solutions and high melt point restrict its processing and applications. In this paper, a series of random copolymers composed of poly(aryl ether ether ketone ketone) (PEEKK)/poly(aryl ether sulfone ether ketone ketone) containing bis(o-metheyl) moiety (DM-PESEKK) were prepared by low temperature solution poly-condensation of 4,4′-bis(2,6-dimethylphenoxy)diphenylsulfone (o-M2DPODPS), 1,4-dipheoxyl-benzene (DPB) and terephthaloyl chloride (TPC) in 1,2-dichloroethane with the presence of AlCl3 and DMF. The copolymers were characterized by FT-IR, DSC, WAXD, TGA, etc. The results show that glass transition temperature increases greatly with the increasing of the ratio of o-M2DPODPS/DPB, while melting temperature and crystallinity of copolymers decrease. The solubility of the copolymers is improved greatly, while the copolymers still exhibit excellent thermostability.