GB831828A - Process for preparing alkylated and aralkylated phenolic condensation products - Google Patents

Abstract

Alkyl or aralkyl phenolic compounds are obtained by reacting phenols with aryl substituted alkene hydrocarbons and/or tertiary olefins having 4-8 carbon atoms in the molecule in the presence of an acidic condensation catalyst and in the presence of tri-isobutylene as a diluent. The reaction may be effected at 70-80 DEG C. Specified phenols include phenol itself, p-octyl phenol, hydroquinone, resorcinol, catechol, pyrogallol, phenyl phenol, naphthols, hydroxy biphenyls, alkylidine bis-phenols. Specified aryl-substituted alkene hydrocarbons include styrene, alpha-methyl-p-methyl styrene, beta-methyl styrene, 2-methyl-allyl benzene, isopropenyl naphthalene, and 1-phenyl pentene. Specified tertiary olefins of 4-8 carbon atoms include isobutylene, iso-amylene, 2-methyl pentene-1, 2-methyl hexene-1, and di-isobutylene. The acidic catalyst may be boron trifluoride, sulphuric acid, phosphoric acid, a hydrocarbon sulphonic acid, a hydrogen halide, or an activated clay. The tri-isobutylene used as diluent may be used in a proportion of 50-200 parts by weight per 100 parts by weight of reactants. Products obtained by reacting 2,2-bis-(4-hydroxyphenyl)-propane with isobutylene or di-isobutylene and/or styrene and styrene hydrocarbons including alpha-methyl styrene, vinyl toluene, and ethyl styrene are specified. These products may be used as antioxidants, preservatives, and age resistors for organic materials, particularly petroleum products, and natural and synthetic rubbers. Preferably the reaction is carried out under a nitrogen atmosphere. In an example, an alkylated-aralkylated bis-phenol is obtained by heating under vacuum at 70-80 DEG C. a mixture of 2,2-bis-(4-hydroxyphenyl)-propane, styrene, isobutylene, acid-activated clay as catalyst, and tri-isobutylene as diluent, the isobutylene being added gradually to the mixture during the course of the reaction.