Quantitative carbon-13 solid-state nmr and FT-Raman spectroscopy in novolac resins

Abstract

A qualitative and quantitative study of the curing behaviour of a high-ortho novolac resin with paraformaldehyde under different conditions is reported. The extent of cure by means of the formaldehyde/phenol ratio, the degree of conversion, and the characterization of the final structure after curing are determined based on quantitative C-13 solid-state nuclear magnetic resonance with cross polarization and magic angle spinning. The T-1H relaxation time is measured as a probe to follow the evolution of cure. In conjunction Fourier transform-Raman spectroscopy is proposed as a qualitative tool to follow the degree of crosslinking in this high-ortho novolac. (C) 1998 Elsevier Science Ltd. All rights reserved.