a novel process is disclosed for the polymerization of phenols , e . g ., xylenols , and recovery of polyphenylene ethers from the polymerization mixture . the method is based on the use of hot methylene chloride as a reaction solvent , elevated oxygen pressure and separation of the polyphenylene ether as a solid complex with methylene chloride upon cooling . also a feature is the recycle and recovery of methylene chloride .