阅读说明：本技术 一种c4-6大单体混合合成聚羧酸高性能减水剂的方法 (C4-6Method for synthesizing polycarboxylic acid high-performance water reducing agent by mixing macromonomers ) 是由 徐大勇 曾锦涛 于 2021-03-12 设计创作，主要内容包括：本发明提供了一种C-(4-6)大单体混合合成聚羧酸高性能减水剂的方法,包括如下步骤：1)基础原料的制备：在反应容器一中加入大单体,水,还原剂和过氧化物,搅拌；2)A料的制备：在反应容器二加入六碳大单体和水,再加入小单体,搅拌均匀；3)B料的制备：在反应容器三加入链转移剂,还原剂和水,搅拌均匀；4)聚合反应：将反应容器一内温度控制在8-30℃范围内,向反应容器一内滴加A料和B料,A料滴加时间为140-160min,B料滴加时间为180-190min,反应温度控制在22-58℃；B料滴加完毕,保温60-70min,加入碱液,搅拌10-15min,得到混凝土高性能减水剂。(The invention provides a compound C 4‑6 The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following steps: 1) preparing a basic raw material: adding a macromonomer, water, a reducing agent and peroxide into a reaction container I, and stirring; 2) preparation of material A: adding a six-carbon macromonomer and water into the reaction container II, adding a small monomer, and uniformly stirring; 3) preparation of material B: adding a chain transfer agent, a reducing agent and water into the reaction container III, and uniformly stirring;4) polymerization reaction: controlling the temperature in the first reaction container within the range of 8-30 ℃, dropwise adding the material A and the material B into the first reaction container, wherein the dropwise adding time of the material A is 140-190 min, the dropwise adding time of the material B is 180-190min, and the reaction temperature is controlled at 22-58 ℃; and after the material B is dripped, preserving the heat for 60-70min, adding alkali liquor, and stirring for 10-15min to obtain the concrete high-performance water reducing agent.)

1. C_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers is characterized by comprising the following steps:

1) preparing a basic raw material: adding macromonomer TPEG or HPEG and water (deionized water or tap water) into the first reaction vessel, and stirring; adding a reducing agent and peroxide, and stirring for 10-15 minutes;

2) preparation of material A: adding six-carbon macromonomer (VPEG \ EPEG \ GPEG) and water into the reaction vessel II, stirring until the mixture is transparent, adding small monomer, and stirring uniformly for later use;

3) preparation of material B: adding a chain transfer agent, a reducing agent and water into the reaction vessel III, and uniformly stirring for later use;

4) polymerization reaction: controlling the temperature in the first reaction container within the range of 8-30 ℃, dropwise adding the material A and the material B into the first reaction container, wherein the dropwise adding time of the material A is 140-190 min, the dropwise adding time of the material B is 180-190min, and the reaction temperature is controlled at 22-58 ℃; and after the material B is dripped, preserving the heat for 60-70min, adding alkali liquor, and stirring for 10-15min to obtain the concrete high-performance water reducing agent.

2. According to the claimsC according to claim 1_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers is characterized in that the mass percentage of each component in the basic raw materials is as follows: 52.55-59.31% of macromonomer, 39.54-46.72% of water, 0.79-1.33% of reducing agent and 0.36-1.72% of peroxide.

3. C according to claim 1_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following components in percentage by mass in the material A: 18.02-51.28% of six-carbon macromonomer, 40.94-63.06% of water and 7.70-18.92% of small monomer.

4. C according to claim 1_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following components in percentage by mass in the material B: 0.1-1.04% of chain transfer agent, 0.5-1.46% of reducing agent and 97.66-9.4% of water.

5. C according to claim 1_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following raw materials in percentage by mass: the basic raw materials are as follows: 39.5% -60.43%; 19.58% -44.15% of the material A; 13.03% -19.82% of the material B; 1.13 to 2.39 percent of alkali liquor.

6. C according to claim 1_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the step of mixing the macromonomers, wherein the reducing agent is one or a combination of L-ascorbic acid, formaldehyde sodium hyposulfite and sodium metabisulfite.

7. C according to claim 1_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the step of synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers, wherein the peroxide is one or a combination of more of hydrogen peroxide, ammonium persulfate, potassium persulfate and sodium persulfate.

8. C according to claim 1_4-6Large sheetThe method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the monomers comprises the step of synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the monomers, wherein the small monomer is one or a plurality of combinations of acrylic acid, methacrylic acid, maleic acid and fumaric acid.

9. C according to claim 1_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the step of synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers, wherein the chain transfer agent is one or a combination of more of mercaptoethanol, mercaptoacetic acid, mercaptopropionic acid and mercaptoethylamine.

Technical Field

The invention relates to the technical field of water reducing agent production, and specifically relates to C_4-6A method for synthesizing a polycarboxylic acid high-performance water reducing agent by mixing macromonomers.

Background

The preparation process of the novel environment-friendly water reducing agent comprises the steps of firstly, preparing polyoxyethylene unsaturated carboxylic ester with polymer activity, namely polyether macromonomer, by using unsaturated monomers such as allyl alcohol, methyl allyl alcohol and isopentenol as initiators and catalyzing under an alkaline condition, and then, preparing the polycarboxylic water reducing agent by utilizing the prepared macromonomer to perform polymerization reaction. The polyether macromonomer accounts for more than 80% of the mass of the polycarboxylate superplasticizer dry agent, and is a crucial basic raw material of the polycarboxylate superplasticizer.

At present, five types of common polyether macromonomers include APEG (allyl polyoxyethylene ether), HPEG (methallyl alcohol polyoxyethylene ether), IPEG (isopentenyl polyoxyethylene ether), EPEG (ethylene glycol monovinyl polyethylene glycol ether) and VPEG (4-hydroxybutyl vinyl polyoxyethylene ether). Wherein VPEG is C₆A monomer.

Research shows that the free radical polymerization reaction is a nucleophilic addition reaction of free radicals (electron-rich groups), and the lower the electron cloud density of double bonds, the higher the reaction activity of the double bonds. However, double bond activity is affected by steric hindrance and the electron effect of the attached group, where methyl is the electron donating group, -O-, and ester is the electron withdrawing group. Based on the above, the reactivity of the polyether macromonomer is from high to low EPEG & gt VPEG & gt APEG & gt HPEG & gt IPEG, and the high reactivity means that the reaction conditions are not harsh (low-temperature polymerization can be carried out), and means that the control is not good. For example: the polymerization temperature of VPEG is generally 10-35 ℃ and experiments show that: under the condition of the same raw material proportion, the reaction temperature is different, and the fluidity index of the reaction dispersion performance is obviously changed. The following table 1 shows the fluidity of the polycarboxylic acid water reducer obtained by VPEG polymerization reaction at different reaction temperatures in the same raw material ratio.

TABLE 1 fluidity of VPEG polymerization products at the same raw material ratio and different reaction temperatures

Test No	Dropping initiation temperature	Maximum temperature	Degree of fluidity
				1	8	25	220
2	10	25	220
				3	15	30	210
4	20	35	185
				5	25	38	160
6	30	35	160

In the production process of the polycarboxylate water reducer, in order to ensure the dispersing performance of the polycarboxylate water reducer, chilled water is usually adopted for cooling to control the temperature, so that the energy consumption in the production process can be increased, and particularly in summer, the energy consumption is extremely high.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a C_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers adopts the six-carbon macromonomer and the four-carbon and/or five-carbon monomer to prepare the polycarboxylic acid high-performance water reducing agent, the method can be carried out under the normal temperature condition, and the produced polycarboxylic acid high-performance water reducing agent has good fluidity, high water reducing rate and low slump loss.

The technical scheme of the invention is as follows: c_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following steps:

1) preparing a basic raw material: adding macromonomer TPEG or HPEG and water (deionized water or tap water) into the first reaction vessel, and stirring; adding a reducing agent and peroxide, and stirring for 10-15 minutes;

2) preparation of material A: adding six-carbon macromonomer (VPEG \ EPEG \ GPEG) and water into the reaction vessel II, stirring until the mixture is transparent, adding small monomer, and stirring uniformly for later use;

3) preparation of material B: adding a chain transfer agent, a reducing agent and water into the reaction vessel III, and uniformly stirring for later use;

4) polymerization reaction: controlling the temperature in the first reaction container within the range of 8-30 ℃, dropwise adding the material A and the material B into the first reaction container, wherein the dropwise adding time of the material A is 140-190 min, the dropwise adding time of the material B is 180-190min, and the reaction temperature is controlled at 22-58 ℃; and after the material B is dripped, preserving the heat for 60-70min, adding alkali liquor, and stirring for 10-15min to obtain the concrete high-performance water reducing agent.

In the basic raw material, the mass percentage of each component is as follows: 52.55-59.31% of macromonomer, 39.54-46.72% of water, 0.79-1.33% of reducing agent and 0.36-1.72% of peroxide;

in the material A, the mass percentage of each component is as follows: 18.02-51.28% of six-carbon macromonomer, 40.94-63.06% of water and 7.70-18.92% of small monomer;

in the material B, the mass percentage of each component is as follows: 0.1-1.04% of chain transfer agent, 0.5-1.46% of reducing agent and 97.66-9.4% of water.

The synthesized polycarboxylic acid high-performance water reducer comprises the following raw materials in percentage by mass: the basic raw materials are as follows: 39.5% -60.43%; 19.58% -44.15% of the material A; 13.03% -19.82% of the material B; 1.13 to 2.39 percent of alkali liquor.

The reducing agent is one or the combination of a plurality of L-ascorbic acid, formaldehyde sodium hyposulfite and sodium pyrosulfite.

The peroxide is one or a combination of more of hydrogen peroxide, ammonium persulfate, potassium persulfate and sodium persulfate.

The small monomer is one or a plurality of combinations of acrylic acid, methacrylic acid, maleic acid and fumaric acid.

The chain transfer agent is one or a combination of several of mercaptoethanol, mercaptoacetic acid, mercaptopropionic acid and mercaptoethylamine.

The invention has the beneficial effects that: the polycarboxylic acid high-performance water reducing agent prepared by the invention can react under the condition of normal temperature, and the produced polycarboxylic acid high-performance water reducing agent has the advantages of good fluidity, high water reducing rate, low slump loss, qualified compressive strength and high content.

Detailed Description

In order to make the object, technical solution and technical effect of the present invention more apparent, the present invention will be further described with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example one C_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following steps:

1) adding the macromonomer HPEG-3000150 g and 100g of water into a first reaction vessel, and stirring; adding 2g of L-ascorbic acid and 0.9g of ammonium persulfate, and stirring for 10-15 minutes;

2) preparation of material A: adding six-carbon macromonomer VPEG-300050 g and 100g of water into a second reaction vessel, stirring until the mixture is transparent, adding 22g of acrylic acid, and stirring uniformly for later use;

3) preparation of material B: adding 0.17g of mercapto propanol serving as a chain transfer agent, 0.3g of L-ascorbic acid serving as a reducing agent and 65g of water into a reaction vessel III, and uniformly stirring for later use;

4) polymerization reaction: controlling the temperature in the first reaction container within the range of 8-30 ℃, dropwise adding the material A and the material B into the first reaction container, wherein the dropwise adding time of the material A is 140-190 min, the dropwise adding time of the material B is 180-190min, and the reaction temperature is controlled at 22-58 ℃; and after the material B is dripped, preserving the heat for 60-70min, adding NaOH with the mass concentration of 32%, and stirring for 10-15min to obtain the concrete high-performance water reducing agent.

Example two A_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following steps:

1) adding 70g of water and 70g of macromonomer HPEG-2400100 into the first reaction vessel, and stirring; adding 1.5g of L-ascorbic acid and 3g of hydrogen peroxide, and stirring for 10-15 minutes;

2) preparation of material A: adding 80g of water and VPEG-3000100 g of six-carbon macromonomer into a second reaction vessel, stirring until the mixture is transparent, adding 15g of methacrylic acid, and stirring uniformly for later use;

3) preparation of material B: adding 0.17g of mercaptoacetic acid serving as a chain transfer agent, 0.5g of L-ascorbic acid serving as a reducing agent and 66g of water into a reaction container III, and uniformly stirring for later use;

4) polymerization reaction: controlling the temperature in the first reaction container within the range of 8-30 ℃, dropwise adding the material A and the material B into the first reaction container, wherein the dropwise adding time of the material A is 140-190 min, the dropwise adding time of the material B is 180-190min, and the reaction temperature is controlled at 22-58 ℃; and after the material B is dripped, preserving the heat for 60-70min, adding NaOH with the mass concentration of 32%, and stirring for 10-15min to obtain the concrete high-performance water reducing agent.

Example three one C_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following steps:

1) adding 70g of macromonomer TPEG-3000120 g and water into a first reaction vessel, and stirring; adding 3g of sodium formaldehyde sulfoxylate and 2g of sodium persulfate, and stirring for 10-15 minutes;

2) preparation of material A: adding 70g of water and 70g of six-carbon macromonomer VPEG-300080 g into a second reaction vessel, stirring until the mixture is transparent, adding 21g of methacrylic acid, and stirring uniformly for later use;

3) preparation of material B: adding 0.1g of mercaptoethylamine serving as a chain transfer agent, 0.5g of sodium bisulfite formaldehyde serving as a reducing agent and 100g of water into a reaction vessel III, and uniformly stirring for later use;

4) polymerization reaction: controlling the temperature in the first reaction container within the range of 8-30 ℃, dropwise adding the material A and the material B into the first reaction container, wherein the dropwise adding time of the material A is 140-190 min, the dropwise adding time of the material B is 180-190min, and the reaction temperature is controlled at 22-58 ℃; and after the material B is dripped, preserving the heat for 60-70min, adding NaOH with the mass concentration of 32%, and stirring for 10-15min to obtain the concrete high-performance water reducing agent.

Example four one C_4-6The method for synthesizing the polycarboxylic acid high-performance water reducing agent by mixing the macromonomers comprises the following steps:

1) adding 160g of macromonomer TPEG-2400180 g and water into a first reaction vessel, and stirring; adding 0.5g of sodium metabisulfite and 2g of potassium persulfate, and stirring for 10-15 minutes;

2) preparation of material A: adding 70g of water and 70g of six-carbon macromonomer VPEG-300020 g into a second reaction vessel, stirring until the mixture is transparent, adding 21g of methacrylic acid, and stirring uniformly for later use;

3) preparation of material B: adding 0.9g of mercaptopropionic acid serving as a chain transfer agent, 1.5g of sodium formaldehyde bisulfite serving as a reducing agent and 100g of water into a reaction vessel III, and uniformly stirring for later use;

4) polymerization reaction: controlling the temperature in the first reaction container within the range of 8-30 ℃, dropwise adding the material A and the material B into the first reaction container, wherein the dropwise adding time of the material A is 140-190 min, the dropwise adding time of the material B is 180-190min, and the reaction temperature is controlled at 22-58 ℃; and after the material B is dripped, preserving the heat for 60-70min, adding NaOH with the mass concentration of 32%, and stirring for 10-15min to obtain the concrete high-performance water reducing agent.

In order to detect and verify the performance of the polycarboxylic acid high-performance water reducing agent synthesized by mixing the C4-6 macromonomer, the performance is detected according to GB/T8077-2012 concrete admixture homogeneity detection method and GB8076-2008 concrete admixture. The results are shown in table 1 below, where the fluidity is measured: W/C is 0.29; folding and fixing mixing amount: 0.1 percent; and (3) concrete performance detection: the folded solid content is 0.18 percent.

Table 1 results of performance tests on polycarboxylic acid high-performance water reducing agent prepared in example 1

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the present invention pertains, the architecture form can be flexible and varied without departing from the concept of the present invention, and a series of products can be derived. But rather a number of simple derivations or substitutions are made which are to be considered as falling within the scope of the invention as defined by the appended claims.