Phenolic resins

摘要

This invention relates to a process for producing low molecular weight phenol-aldehyde resin which has predominantly 4 phenolic units in a chain and in which the phenolic ring has a substituent R which is an alkyl group and optionally contains methylol groups on either end of the chain, by reacting formaldehyde with p-alkyl phenol in the presence of ammonia as base in a liquid reaction medium. The resins can be used in producing demulsifiers.