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Official Journal of the Japan Wood Research Society

Analysis of phenol-resorcinol-formaldehyde resins


A method based on high-performance liquid chromatography (HPLC) and proton magnetic resonance (PMR) spectroscopy for analyzing phenol-resorcinolformaldehyde (PRF) resins is reported. The equations that describe the number-averaged structures of PRF resins in terms of the PMR absorption intensities of acetylated resins have been derived on the basis of the work of Woodbrey et al. and Anderson et al. The P/R molar ratio of the resin calculated from the PMR intensities was in good agreement with the synthetic P/R molar ratio when correction was made for the loss of phenol evaporated during the drying process that preceded the acetylation. The number-averaged molecular weight (Mn) of the acetylated resin calculated from the PMR intensities agreed with the Mn determined by cryoscopy. Unreacted phenol and resorcinol could be determined by analyzing the water-soluble fraction of the resin by use of high-performance liquid chromatography.


  1. 1.

    Woodbrey JC, Higginbottom HP, Culbertson HM (1965) Proton magnetic resonance study on the structures of phenol-formaldehyde resins. J Polymer Sci A 3:1079–1106

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  2. 2.

    Anderson R, Haines AH, Stark BP (1972) Analysis of resorcinolphenol-formaldehyde resins by NMR spectroscopy. Angew Makromol Chem 26:171–176

    CAS  Article  Google Scholar 

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Correspondence to Mitsuo Higuchi.

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Datta, S.K., Higuchi, M. & Morita, M. Analysis of phenol-resorcinol-formaldehyde resins. J Wood Sci 45, 411–416 (1999).

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Key words

  • Phenol-resorcinol-formaldehyde resins
  • PMR spectroscopic analysis
  • Phenol/resorcinol molar ratio
  • Number-averaged molecular weight
  • Unreacted phenol