AIR-ENTRAINING ADDITIVE AND METHOD OF OBTAINING THEREOF Russian patent published in 2015 - IPC C04B24/22 C04B103/30 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of obtaining and a composition of an air-entraining additive, applied in manufacturing monolith and assembled concrete and reinforced concrete products and constructions, as well as in the oil production industry in a composition of grouting cement materials. In the method of obtaining the air-entraining additive alkylarylsulphonates are obtained by polycondensation of alkylnaphthalenesulphonic acids with formaldehyde with further neutralisation of the reaction mass with sodium hydroxide, with the synthesis of alkylnaphthalenesulphonic acids being realised in the course of a combined alkylation-sulphonation process by a processing mixture of naphthalene and alcohol with a sulphonating agent in an interval of temperatures of 80-165°C with the following ratio of the reaction mass components, mol.%: naphthalene 100 and over 100: alcohol 80-200, sulphonating agent 110-150; polycondensation of alkylnaphthalenesulphonic acids with formaldehyde is carried out in an interval of temperatures of 90-130°C for 20-200 min with the following component ratio, mol.%: alkylnaphthalenesulphonic acids 100 and over 100: formaldehyde 40-80, until the air-entraining additive, representing a water solution with the weight part of dry substances of 5-32% is obtained, with the dry substances consisting of a neutralised mixture of products of polycondensation of alkylnaphthalenesulphonic acids and sodium sulphate with the following component ratio, wt %: neutralised mixture of products of polycondensation of alkylnaphthalenesulphonic acids 70-88, sodium sulphate 12-30. The air-entraining additive, obtained by the said method. The invention is developed in dependent claims of the invention formula.

EFFECT: provision of stable air-entraining into the concrete mixture and obtaining concrete with high frost-resistance.

4 cl, 2 tbl