A nuclear magnetic resonance study of poly (aryl ether ether ketone)

Abstract

Amorphous and crystalline samples of poly(aryl ether ether ketone) have been studied in the solid state by both ¹³C high-resolution cross-polarization/magic-angle spinning (CP/MAS) nuclear magnetic resonance (n.m.r.) and wide-line ¹H n.m.r. The ¹³C spectrum was assigned using the dipolar dephased and variable-contact-time experiments. The CP/MAS spectrum of the amorphous sample displays much broader signals than does the crystalline sample. The ¹H wide-line spectra were measured at temperatures from 295 to 440 K. The ¹H spectra appeared as two superimposed signals having different spin-lattice relaxation times. At all temperatures below the glass transition, the lines of the crystalline spectra were wider and showed longer spin-lattice relaxation times than those of the amorphous spectra.