CN106279562A - A kind of synthesis technique of polycarboxylate water-reducer - Google Patents

Abstract

The synthesis process of the polycarboxylate water reducer of the present invention is characterized in that: P-Ti-Ni-Cr alloy is used to catalyze the decomposition of hydrogen peroxide to obtain the initiating oxygen atoms needed for the copolymerization reaction; chemical plating technology is used on the stirring paddle of the reactor Deposition forms a spongy P-Ti-Ni-Cr alloy coating with nano-scale micropores; synthesis process of polycarboxylate superplasticizer: preparation of liquid A; preparation of liquid B; in a reactor equipped with an electroless plating technology stirring paddle , add water, SPEG macromonomer with a molecular weight of 2400-2600; add liquid A and liquid B dropwise into the reactor; add sodium hydroxide and water into the reactor to obtain a polycarboxylate superplasticizer product. The synthesis process of the polycarboxylate superplasticizer of the present invention solves the problem of unstable polycarboxylate superplasticizer products produced at low and normal temperatures without using a reducing agent, has the characteristics of energy saving and environmental protection, and reduces production costs.

Description

A kind of synthetic technology of polycarboxylate water reducer

technical field

The invention relates to the technical field of chemical industry, belongs to a preparation method of a polycarboxylate water reducer, in particular to a synthesis process of a polycarboxylate water reducer.

Background technique

Water reducer is the most widely used admixture in cement concrete production. At present, polycarboxylate water reducer is the third generation of water reducer after wood calcium and naphthalene water reducer in the prior art in China. Traditionally used polycarboxylate superplasticizers are divided into three methods according to the starting temperature of production: low temperature (0-15°C), normal temperature (20-30°C), and high temperature (40-60°C). With the requirements of energy conservation and environmental protection, the production of polycarboxylate superplasticizers by high-temperature methods has become less and less. The main reason is that the production of polycarboxylate superplasticizers by high-temperature methods has problems such as large equipment investment, long production cycle, and high energy consumption. . The low-temperature production process produces polycarboxylate water-reducers using an oxidation-reduction system instead of peroxides in high-temperature processes to decompose at high temperatures to obtain the initiator oxygen atoms of the copolymerization reaction. The influence of seasonal changes in temperature The initial temperature of production varies greatly, resulting in unstable product quality; sulfites are used as reducing agents in production, and sodium sulfate is produced after reaction, resulting in the production of polycarboxylate superplasticizer products containing Sodium sulfate, resulting in reduced purity.

Contents of the invention

The present invention overcomes the above-mentioned defects, and aims to provide a synthesis process of polycarboxylate water reducer to solve the problem of unstable polycarboxylate water reducer produced at low temperature and normal temperature, to save energy and protect the environment, and to reduce production costs. .

A brief description of the synthesis process of the polycarboxylate water reducer of the present invention:

The synthesis process of the polycarboxylate water reducer of the present invention is characterized in that: P-Ti-Ni-Cr alloy is used to catalyze the decomposition of hydrogen peroxide to obtain the initiating oxygen atoms required for the copolymerization reaction; chemical plating technology is used on the stirring paddle of the reactor Deposition forms a spongy P-Ti-Ni-Cr alloy coating with nanoscale micropores;

Synthesis process of polycarboxylate superplasticizer:

(1) Preparation of liquid A: Mix 150-200 kg of acrylic acid, 4-15 kg of mercaptopropionic acid, and 50-100 kg of water to prepare liquid A;

(2) Preparation of liquid B: Mix 5-20 kg of hydrogen peroxide and 150-200 kg of water to prepare liquid B;

(3) Add 1,700 kg of water and 1,000 to 2,000 kg of SPEG macromonomer with a molecular weight of 2,400 to 2,600 in the reaction kettle equipped with the above-mentioned stirring paddle using electroless plating technology;

(4) Add liquid A and liquid B to the reaction kettle dropwise at a rate of 1.5 to 3 hours. First, add liquid B dropwise for 5 minutes before starting to add liquid A. After the addition of liquid A, continue Stir for 0.5 to 1 hour;

(5) Add 50kg of sodium hydroxide and 1100kg of water into the reaction kettle to prepare a polycarboxylate water reducer product.

The synthesis process of the polycarboxylate superplasticizer of the present invention solves the problem of unstable polycarboxylate superplasticizer products produced at low and normal temperatures without using a reducing agent, has the characteristics of energy saving and environmental protection, and reduces production costs.

detailed description

The synthesis technique of the polycarboxylate water reducer of the present invention is realized in this way, and is described in detail below.

The present invention adopts P-Ti-Ni-Cr alloy to catalyze the decomposition of hydrogen peroxide to obtain the initiating oxygen atoms required for the copolymerization reaction; the process is slightly affected by temperature, and the production speed of oxygen atoms is close to that under the same hydrogen peroxide concentration and different temperature conditions;

The electroless plating technology is used to deposit the spongy P-Ti-Ni-Cr alloy coating with nano-scale micropores on the stirring paddle of the reactor. During the production process, the P-Ti-Ni-Cr alloy coating will not be damaged before a large area is damaged. Needs to be remade.

The synthetic technique of polycarboxylate water reducer of the present invention:

(1) Preparation of liquid A: Mix 150-200 kg of acrylic acid, 4-15 kg of mercaptopropionic acid, and 50-100 kg of water to prepare liquid A;

(2) Preparation of liquid B: Mix 5-20 kg of hydrogen peroxide and 150-200 kg of water to prepare liquid B;

(3) Add 1,700 kg of water and 1,000 to 2,000 kg of SPEG macromonomer with a molecular weight of 2,400 to 2,600 in the reaction kettle equipped with the above-mentioned stirring paddle using electroless plating technology;

(4) Add liquid A and liquid B to the reaction kettle dropwise at a rate of 1.5 to 3 hours. First, add liquid B dropwise for 5 minutes before starting to add liquid A. After the addition of liquid A, continue Keep warm for 0.5 to 1 hour;

(5) Add 50kg of sodium hydroxide and 1100kg of water into the reaction kettle to obtain polycarboxylate superplasticizer products. The products obtained are the same regardless of the initial temperature during the production process.

The invention is not affected by seasons, and the products obtained under the condition of the initial temperature of 0-40 DEG C are the same, the stability of the products is improved, no reducing agent needs to be added in the production, and the production cost is saved.

Embodiment one

The synthetic technique of preparing polycarboxylate water reducer of the present invention under low temperature conditions:

(1) At a temperature of 3°C, add 170g of water and 165g of SPEG macromonomer in turn into a four-neck flask equipped with an electroless plating technology stirring paddle, and stir until dissolved;

(2) Prepare liquid A with 20g of acrylic acid, 1.25g of mercaptopropionic acid, and 20g of water;

(3) Make liquid B with 2g hydrogen peroxide and 40g water;

(4) Add liquid A and liquid B dropwise to the four-neck flask at a rate of 3 hours. First add liquid B dropwise for 5 minutes, then start to add liquid A dropwise, and continue stirring after the addition of liquid A is completed. 1 hour;

(5) Add 5g of sodium hydroxide and 110g of water into a four-necked flask to prepare a polycarboxylate superplasticizer product.

Embodiment two

The synthetic technique of preparing the polycarboxylate water reducer of the present invention under normal temperature conditions:

(1) At a temperature of 30°C, add 170g of water and 165g of SPEG macromonomer in turn into a four-neck flask equipped with an electroless plating technology stirring paddle, and stir until dissolved;

(2) Prepare liquid A with 20g of acrylic acid, 1.25g of mercaptopropionic acid, and 20g of water;

(3) Make liquid B with 2g hydrogen peroxide and 40g water;

(4) Add liquid A and liquid B dropwise to the four-neck flask at a rate of 3 hours. First add liquid B dropwise for 5 minutes, then start to add liquid A dropwise, and continue stirring after the addition of liquid A is completed. 1 hour;

(5) Add 5g of sodium hydroxide and 110g of water into a four-necked flask to prepare a polycarboxylate superplasticizer product.

The polycarboxylate water-reducers obtained in the above-mentioned examples 1 and 2 were tested by laboratory tests, and the water-reducing rate and slump were basically the same over time.

The synthesis process of the polycarboxylate superplasticizer of the present invention greatly reduces the influence of the initial temperature on the final performance of the product during production, and solves the problem of producing polycarboxylate superplasticizer products at low temperature and normal temperature without using a reducing agent. Stable problem, with the characteristics of energy saving and environmental protection, which reduces the production cost.

Claims (3)

1. A synthesis technique of polycarboxylate water reducer, characterized in that: adopt P-Ti-Ni-Cr alloy to catalytically decompose hydrogen peroxide, obtain the initiating oxygen atom needed for copolymerization; adopt electroless plating technology to stir in reactor A spongy P-Ti-Ni-Cr alloy coating with nanoscale pores is deposited on the paddle; Synthesis process of polycarboxylate superplasticizer: (1) Preparation of liquid A: Mix 150-200 kg of acrylic acid, 4-15 kg of mercaptopropionic acid, and 50-100 kg of water to prepare liquid A; (2) Preparation of liquid B: Mix 5-20 kg of hydrogen peroxide and 150-200 kg of water to prepare liquid B; (3) Add 1,700 kg of water and 1,000 to 2,000 kg of SPEG macromonomer with a molecular weight of 2,400 to 2,600 in the reaction kettle equipped with the above-mentioned stirring paddle using electroless plating technology; (4) Add liquid A and liquid B to the reaction kettle dropwise at a rate of 1.5 to 3 hours. First, add liquid B dropwise for 5 minutes before starting to add liquid A. After the addition of liquid A, continue Stir for 0.5 to 1 hour; (5) Add 50kg of sodium hydroxide and 1100kg of water into the reaction kettle to prepare a polycarboxylate water reducer product. 2. The synthesis process of polycarboxylate water reducer according to claim 1, characterized in that: the synthesis process of polycarboxylate water reducer is prepared under low temperature conditions: (1) At a temperature of 3°C, add 170g of water and 165g of SPEG macromonomer in turn into a four-neck flask equipped with an electroless plating technology stirring paddle, and stir until dissolved; (2) Prepare liquid A with 20g of acrylic acid, 1.25g of mercaptopropionic acid, and 20g of water; (3) Make liquid B with 2g hydrogen peroxide and 40g water; (4) Add liquid A and liquid B dropwise to the four-neck flask at a rate of 3 hours. First add liquid B dropwise for 5 minutes, then start to add liquid A dropwise, and continue stirring after the addition of liquid A is completed. 1 hour; (5) Add 5g of sodium hydroxide and 110g of water into a four-necked flask to prepare a polycarboxylate superplasticizer product. 3. The synthesis process of polycarboxylate water reducer according to claim 1, characterized in that: the synthesis process of polycarboxylate water reducer is prepared under normal temperature conditions: (1) At a temperature of 30°C, add 170g of water and 165g of SPEG macromonomer in turn into a four-neck flask equipped with an electroless plating technology stirring paddle, and stir until dissolved; (2) Prepare liquid A with 20g of acrylic acid, 1.25g of mercaptopropionic acid, and 20g of water; (3) Make liquid B with 2g hydrogen peroxide and 40g water; (4) Add liquid A and liquid B dropwise to the four-neck flask at a rate of 3 hours. First add liquid B dropwise for 5 minutes, then start to add liquid A dropwise, and continue stirring after the addition of liquid A is completed. 1 hour; (5) Add 5g of sodium hydroxide and 110g of water into a four-necked flask to prepare a polycarboxylate superplasticizer product.