ACRYLIC ACID POLYMER, OBTAINING SOLUTION OF ACRYLIC ACID POLYMER AND ITS USE AS INHIBITOR OF DEPOSITS IN WATER SUPPLY SYSTEMS Russian patent published in 2022 - IPC C08F220/06 C08F2/38 C08F2/10 C08L33/02 C02F5/14 

FIELD: chemistry.

SUBSTANCE: invention relates to acrylic acid polymers (hereinafter – AAP), a solution of acrylic acid polymer, a method for their preparation, as well as to their use as inhibitors of deposits in water supply systems. Acrylic acid polymer obtained by polymerization of acrylic acid monomer in the presence of sodium hypophosphite and sodium phosphite is characterized by average molecular weight from 1000 to 15,000 g/mol, a polydispersity coefficient (K_n) of more than 2.5, wherein the amount of phosphorus inside a polymer chain is up to 75% of the total phosphorus content, the amount of phosphorus attached to ends of the polymer chain is up to 40% of the total phosphorus content. An aqueous solution is obtained by polymerization of acrylic acid in water as a solvent, peroxodisulfate as an initiator and in the presence of a mixture of sodium hypophosphite and sodium phosphite as a regulator. At the same time, the ratio of hypophosphite/sodium phosphite is 95:5. The method is implemented by pre-preparing a solution of 1/10 of the total weight of the regulator and subsequent simultaneous supplying reagent flows: initiator, 1/10 of the regulator and the regulator with acrylic acid at a temperature from 75 to 85°C. Flows are fed linearly, that is, without changing the speed during the entire supply time.

EFFECT: decrease in deposits of metal salts, in particular calcium salts in water supply systems, the value of which is expressed in an increase in the binding capacity of the AAP solution to calcium salt over 750 mg of CaCO₃/g.

48 cl, 1 tbl, 6 ex