FIELD: technological processes.
SUBSTANCE: invention relates to a process for the preparation of alkyl hydroxyalkyl cellulose and the use of such alkyl hydroxyalkyl cellulose for the preparation of mortars and other systems based on cement. Process for the production of alkyl hydroxyalkyl cellulose includes: a) mixing an alkaline solution containing an alkali metal hydroxide with a cellulose and an alkyl halide at a temperature of at least 10 °C, to obtain a first reaction mixture containing alkaline cellulose, water and an alkyl halide; b) setting the temperature of the first reaction mixture to be 50 to 110 °C, resulting in the reaction of a portion of the alkyl halide with alkali cellulose, and preparing a second reaction mixture containing alkyl cellulose and unreacted alkyl halide, where the second reaction mixture is maintained at a temperature in the range of from 50 to 110 °C; c) adding alkylene oxide to the second reaction mixture obtained in step b) to obtain a third reaction mixture; d) setting the temperature of the third reaction mixture so that it is in the range of from 80 to 110 °C, and reacting at least a portion of the alkyl cellulose: i) with at least a portion of the alkylene oxide, and ii) with at least part of the unreacted alkyl halide, and thus the production of the fourth reaction mixture; and e) recovering the alkyl hydroxyalkyl cellulose from the fourth reaction mixture.
EFFECT: method is proposed for the preparation of alkyl hydroxyalkyl celluloses, as well as dry solution mixtures containing encapsulated calcium chloride used to prepare mortars, intended for use in construction with the use of such mortars in cold weather conditions.
12 cl, 3 dwg, 28 tbl
