BLOCK POLYMERS CONTAINING ESTER GROUPS AS ANTI-FOAMING AGENTS FOR AQUEOUS SYSTEMS

摘要

A foaming regulator, which can universally be used in aqueous systems with a foaming tendency, has a good spontaneous effect in small quantities and maintains its effect for a long time, can be tailored in such a way that it is effective even at low temperatures and nevertheless develops its effect over a wide temperature range, can be produced in the form of a pourable foam regulating agent and, when added to ready-made washing and cleaning agents, is active over a wide temperature range, facilitates even coverage in the dye and paint industry and makes possible uniform colouring in paper coating without adversely affecting the surface, is a block polyester consisting of hydrophobic segments A and hydrophilic segments B, in which segment A is the acid radical of a mixture of 50 to 100 wt % of unsaturated epoxidised, open-ringed with alcohol carboxylic acids and/or carboxylic acid esters and up to 50 wt % of saturated aliphatic carboxylic acids and/or carboxylic acid esters, in relation to the mixture, and segment B is a polyethylene glycol radical. Such a polymer may be used as such or in the form of a granular, pourable foam regulator containing 0.5 to 30 wt % of the block polyester adsorbed onto 70 to 99.5 wt % of a granular, phosphate-free and water soluble or water dispersible vehicle.