Salient: Victoria University Students' Paper. Vol. 29, No. 6. 1966.
Phenolic resins
Phenolic resins
The phenolics constitute one of the oldest resin groups. The basic make up is similar for the surface coating industry and the plastic industry. There are several New Zealand manufacturers of the surface coating type but the plastic type is mainly imported.
The phenolics are condensation products of a phenol and an aldehyde. Formaidehyde is by far the most reactive aldehyde and is almost exclusively used, as the paraformaldehyde, in commercial production. The phenol types used can be phenol. m-cresol. p-tertiary butyl phenol and a number of others. The nature of the final product is dependent of the types and ratios of the reacting ingredients.
In the paint or surfs coating industry the phenol resin so produced is [ unclear: furth] modified by heat reacting on tung oil. The varnish so [ unclear: duced] is used as water alkali resistant primers [ unclear: sealers] and interior varnishes. Their effectiveness is not to the standards of urethanes or expoxies but adequate for most purposes.
The surface coating [ unclear: che] can modify these varnishes controlling the [ unclear: polymeri] and by modifying the phenolic ratio.
With phenolic plastics manufacture enfalls covering the condensation [ unclear: pro] into a brittle low molecule weight compound which suitably pigmented over rollers.
This mix is then cooled the form of sheets and [ unclear: gro] into moulding powder.
During subsequent [ unclear: mould] enough heat is applied completely cross link phenol condensate into a insoluble and infusible [ unclear: duet].
As can be seen, the difference between a paint phenol resin and a plastic phenol is the absence of a modifying oil in the latter. Phenol plastic articles are hard, and strong. They have no heat resistance and are celient insulators. Uses include handles of cooking utensil irons etc, and wash machine agitators.