Verwendung von mit alpha-Olefinepoxiden umgesetzten Ethylenoxid/Propylenoxid-Anlagerungsverbindungen des Glycerins oder Polyglycerins als Entschäumer

摘要

The invention concerns the use of glycerol or polyglycerol addition compounds of general formula (I)[R]x-(EO)n-(PO)n-(AO)p-H, in which [R]x stands for a glycerol or polyglycerol group and EO designates an ethylene oxide unit, PO designates a propylene oxide unit and AO designates a group of formula (II), in which R' designates a linear alkyl group with between 2 and 18 carbon atoms, x is a number between 1 and 6, n is a number between 5 and 60, m is a number between 30 and 300, and p is a number between 1 and 10. The compound of formula (I) is prepared by adding n mol EO and m Mol PO per mol of glycerol or polyglycerol in a first step. In a second step, p mol of a linear alpha-olefin epoxide with between 4 and 20 carbon atoms per mol of alkoxylated glycerol or polyglycerol is added. The substances are used as antifoaming agents in aqueous systems, for example in the food, paper, paint and dye-making industries.