The Technology of Phenol‐Formaldehyde Moulding Powders 1 ‐ Characterisation of Novolak Resins and Derived Moulding Powders

Abstract

This research programme has been concerned with the technology of phenol-formaldehyde resins and of moulding powders based on them. This paper reports the characterisation of the prepolymer (Novolak) and concentrates on the results obtained by gel permeation chromatography with an infrared detector. A variety of frequencies have been employed, corresponding to different components in the resin, and the best separation was obtained by monitoring the phenolic hydroxyl at 3400 cm−1. It has been concluded that both commercial Novolak and prepolymer extracted from moulding powder contain a substantial fraction of high molecular weight material.