FIELD: organic chemistry. SUBSTANCE: alkyl phenol having 4-12 carbon atoms in alkyl chain is condensed with side product of isoprene production having high boiling point or with 4,4-dimehyldioxane, molar ratio of components being 1;05-2 respectively. Thus prepared product is affected by oxyethylation till content of oxyethyl groups in desired product is 30-70 mass Mentioned above isoprene is prepared of isobutylene and formaldehyde. EFFECT: improves efficiency of the method. 2 cl, 4 tbl
