Copolymers suitable for reducing the formation of magnesium hydroxide containing scale

摘要

The invention relates to the use of a copolymer, which consists of at least 95% by weight, based on the total weight of the copolymer in its acid form, of a combination of polymerized units of acrylic acid and polymerized units of a C₁-C₃ alkyl acrylate, where the amount of polymerized units of the C₁-C₃ alkyl acrylate is in the range from 3 to 30% by weight, based on the total weight of the copolymer in its acid form, and where the copolymer in the form of its sodium salt has a weight average molecular weight Mw in the range from 500 to 4000 g/mol, as determined by gel permeation chromatography, for reducing the formation of magnesium hydroxide containing scale. The invention also relates to a method for reducing the formation of magnesium hydroxide containing scale in a water-treatment unit for processing Mg containing water, which comprises the addition of a copolymer as defined herein to the Mg containing water to be treated in the water-treatment unit.