US Patent 7977284 Non-estrogenic alkylphenol derivatives

A method of making phenol and alkylphenol ethoxylates non-estrogenic by inserting 1 mole of propylene oxide onto the phenolic group before proceeding with the addition of ethylene oxide or mixtures of ethylene and propylene oxide. The final phenolic products can be further reacted to form sulfates, sulfonates, phosphate esters, condensed alkylphenol alkoxylates and other derivatives of alkylphenol or phenol. Non-estrogenic phenol and alkylphenol alkoxylates and their derivatives have been found to be excellent salt tolerant, high temperature stable surfactants for oil recovery from subterranean reservoirs. These products are also useful in forming emulsions of heavy crude for transportation through pipelines.