CHARACTERIZATION OF THE CHAIN DYNAMICS OF PEEK BY CPMAS C-13 NMR

Dipolar rotational spin-echo, T1(C), T1ρ(C), and both direct and indirect T1ρ (H) relaxation experiments have been performed on partially crystalline poly(oxy-l,4-phenyleneoxy-l,4-phenylenecarbonyl-1,4-phenylene), commonly known as PEEK. The results of these experiments demonstrate that mainchain aromatic rings are dynamically active in only a relatively small part of the amorphous fraction. Most of the rings in both amorphous and crystalline regions are immobile. On average, the ether-ether rings in the amorphous regions of PEEK are slightly less mobile than the ether-ketone rings, presumably the result of interchain packing in the lattice. © 1990, American Chemical Society. All rights reserved.