One‐ and two‐dimensional NMR study of resol phenol—formaldehyde prepolymer resins

Abstract

AbstractA one‐ and two‐dimensional NMR study was performed on three commercial resol phenol—formaldehyde (PF) prepolymer resins. 1H, 13C, CSCM and DQF COSY NMR spectral data, in acetone‐d6, were obtained on each resin and on PF model compounds: phenol, five methylolphenols, four diphenylmethanes, two formals, two dibenzyl ethers and two dibenzylamines. Gated‐decoupled 13C experiments, using 2,4,6‐trimethylphenol as internal standard, were used to quantitate the major components present in each of the three resins. The major chemical differences of the three resins were noted. A DQF COSY method was developed that allowed the qualitative identification of most of the major phenolic components present in each of the PF resins.