Abstract: The new petroleum breakers are obtained by reacting, at 90.degree. to 160.degree. C. and at a pH value of 6 to 9, (a) an addition product which has been obtained by reacting phenol with formaldehyde or acetaldehyde in a molar ratio of 1:1 to 3 at a temperature of 50.degree. to 80.degree. C., in the presence of an alkaline catalyst, with (b) a block polymer which contains nitrogen and which has been obtained by an addition reaction in which 10 to 80 moles of ethylene oxide and propylene oxide are added on, as a statistical average per nitrogen atom, the molar ratio of ethylene oxide to propylene oxide being 1:0.5 to 14, to ethylenediamine, propylenediamine, polyethylenepolyamines, polypropyleneamines or mixtures thereof, the ratio being 1 to 20 moles of (a) to 1 mole of (b). They are distinguished by a high degree of effectiveness when used for separating petroleum emulsions. Products which in some cases have an even greater effect are obtained if the reaction product of (a) and (b) is propoxylated.

Abstract: The new petroleum breakers are obtained by subjecting (a) an addition reaction product which has been obtained by reacting aliphatic aldehydes with phenol in a molar ratio of 1:1 to 3:1 at temperatures of 50.degree. to 80.degree. C. in the presence of an alkaline catalyst, to a condensation reaction at 80.degree. to 150.degree. C., after prior neutralization and, if appropriate, in the presence of inert solvents, with (b) a block polymer which has been prepared by reacting polypropylene glycols having molecular weights of 1,300 to 3,000 with 20 to 100% by weight of ethylene oxide in the presence of alkaline catalysts, in a ratio of 0.5 to 4 moles of (a) to 1 mole of (b), and removing the water of the reaction which is formed, and (c) adding on 10 to 400 g of propylene oxide, relative to 100 g of condensation product, or 10 to 200 g of ethylene oxide and propylene oxide in a ratio of 1:0.

Abstract: The new compounds consist essentially of ethylene oxide/propylene oxide block polymer units and oxyalkyleneated alkylphenol/aldehyde resin units, which are linked by methylene groups. They are prepared by reacting a block polymer of ethylene oxide and propylene oxide and an oxyalkyleneated alkylphenol/aldehyde resin with formaldehyde. The new compounds constitute especially advantageous breaking agents for petroleum.