Research on synthetic condition of lignosulfonate modified polycarboxylate superplasticizer

Abstract

The invention relates to a research on a synthetic condition of a lignosulfonate modified polycarboxylate superplasticizer. The research on the synthetic condition of the lignosulfonate modified polycarboxylate superplasticizer is characterized by being prepared by performing condensation on lignosulfonate, polyethylene glycol monomethyl ether metacrylic acid ester, acrylic acid and methacrylic acid sodium sulfonate in a ratio of (9-15 percent): (1-5 percent): (5-30 percent): (1-5 percent). An operation method comprises the following steps: mixing lignosulfonate, polyethylene glycol monomethyl ether metacrylic acid ester, acrylic acid and methacrylic acid sodium sulfonate in the ratio to prepare an aqueous solution with certain mass percentage (the mass percentage of water is 70-90 percent); preparing a diacetyl peroxide initiator into an aqueous solution and slowly dropwise adding the two solutions into a three-mouth flask by using a constant pressure dropping funnel; performing reaction for 2-10 hours at the temperature of 60-120 DEG C after the dropping is completed; cooling the system to be at room temperature after the reaction is completed, and regulating pH of the system to be 8-12 by using a sodium hydroxide solution to obtain the lignosulfonate modified polycarboxylate superplasticizer.

Description

technical field [0001] The invention relates to research on synthesis conditions of a lignosulfonate-modified polycarboxylate water reducer, and belongs to the field of chemical preparations. Background of the invention [0002] At present, polycarboxylate water reducer is widely used because of its high water reducing rate, excellent slump retention and excellent reinforcement effect, and has been favored by the concrete engineering field. The main raw material of polycarboxylate water reducer comes from petroleum, the price is high, and it is not a renewable resource. Lignosulfonate is renewable and comes from waste water in the paper industry. It is cheap, but its water-reducing capacity is limited, and it cannot meet the requirements of high-performance concrete for water-reducing agents. Many researchers have physically compounded lignosulfonate and polycarboxylic acid, but the effect of the directly compounded water reducer is greatly affected by the season, the place...

AI Technical Summary

Problems solved by technology

Lignosulfonate is renewable and comes from waste water in the paper industry. It is cheap, but its water reducing capacity is limited and cannot meet the requirements of high performance concrete for water reducing agents.

Many researchers have physically compounded lignosulfonate and polycarboxylic acid, but the effect of the directly compounded water reducer is greatly affected by the season, the place of origin of the cement, and the variety of the blended material, and the water reducing performance is not satisfactory.

Few people have chemically modified these two water reducers