CONFORMATIONAL CHARACTERISTICS OF POLY-ETHER-ETHER-KETONE AND POLY-ETHER-NITRILE

Conformational analyses of poly-ether-ether-ketone (PEEK), poly-ether- nitrile (PEN) and their related polymers were performed using a semi-e mpirical molecular orbital method with the Austin Model 1 Hamiltonian (AM1 method in MOPAC). The minimum energy conformations were in good a greement with those in crystal. structures of PEEK and PEN. The calcul ated characteristic ratios C-infinity of the unperturbed end-to-end di stance according to the rotational isomeric state theory were 3.93 for PEEK and 6.73 for PEN. Numbers of repeating units between adjacent en tanglements were also estimated.