Synthesis of phenol-urea-formaldehyde cocondensed resins from UF-concentrate and phenol

Abstract

A new synthetic method to obtain phenol-urea-formaldehyde cocondensed resins was developed by reacting phenol with "UF-concentrate", which is a kind of urea-formaldehyde (UF) resin prepared with a high molar ratio of formaldehyde to urea (F/U) such as above 2.5. The products were analyzed with ¹³C-NMR spectroscopy and gel permeation chromatography. The ratio of cocondensation and the amount of phenol incorporated into cocondensed resins were found to increase, when the UF-concentrates were prepared under alkaline conditions. It was also found that resol-type cocondensed resins can be synthesized by alkaline treatments of the cocondensed resins which were once prepared under acidic conditions.

Keywords

Phenol, urea, formaldehyde, cocondensed resins, resol, C-13 NMR, structure, GPC

Citation

Tomita, Bunchiro; Ohyama, Mashiko; Hse, Chung-Yun. 1994. Synthesis of phenol-urea-formaldehyde cocondensed resins from UF-concentrate and phenol. Holzforschung 48(6):522-526