阅读说明：本技术 一种超缓凝聚羧酸减水剂用酯类大单体的制备方法 (Preparation method of ester macromonomer for super-retarding polycarboxylate superplasticizer ) 是由 徐仕睿 刘勇 李鹏 刘威 左小青 柳新江 于 2019-09-25 设计创作，主要内容包括：本发明公开了一种超缓凝聚羧酸减水剂用酯类大单体的制备方法,包括如下步骤：①大单体的合成；②大单体的酯化封端。本发明具有如下优点：1、本发明采用新结构4-苯基-1-丁烯-4-醇为起始剂,通过特定环氧化物嵌段聚合,再进行酯化封端完成。2、用本发明制备的酯类大单体合成的聚羧酸减水剂,其分子支链上的单体结构中同时具有了高减水、保坍和超缓凝的功能,即在保持聚羧酸减水剂原有的功能外,同时具有了超缓凝功能。3、本发明所用原料易得,且均为普通化工产品。生产原料全部转化到最终产品中,生产工艺中无“三废”产生,是清洁绿色工艺。4、本发明所用的设备仅为常规反应釜和泵,无需高投资和高维护费用即可实现,提高了经济效益。(The invention discloses a preparation method of an ester macromonomer for a super-retarding polycarboxylate superplasticizer, which comprises the following steps: firstly, synthesizing a macromonomer; ② esterification end capping of macromonomer. The invention has the following advantages: 1. the invention adopts 4-phenyl-1-butylene-4-alcohol with a new structure as an initiator, and is completed by block polymerization of a specific epoxide and esterification end capping. 2. The polycarboxylate superplasticizer synthesized by the ester macromonomer prepared by the invention has the functions of high water reduction, slump loss resistance and super-retarding in the monomer structure on the molecular branch chain, namely, the polycarboxylate superplasticizer has the function of super-retarding while keeping the original function. 3. The raw materials used in the invention are easily available and are common chemical products. The production raw materials are all converted into the final product, and the production process does not generate three wastes, thereby being a clean and green process. 4. The equipment used by the invention is only a conventional reaction kettle and a pump, and can be realized without high investment and high maintenance cost, thereby improving the economic benefit.)

1. A preparation method of an ester macromonomer for a super-retarding polycarboxylate superplasticizer comprises the following steps:

synthesis of a macromonomer: adding 4-phenyl-1-butene-4-ol into a reaction kettle, and simultaneously adding a small amount of alkaline catalyst; after introducing high-purity nitrogen for replacement, keeping the initiation temperature in the reaction kettle at 110-; after the reaction is successfully initiated, increasing the reaction temperature T to 130-; continuously introducing ethylene oxide into the reaction kettle, curing for 1 hour after the feeding is finished, and degassing after curing to obtain a macromonomer;

② esterification end capping of macromonomer: keeping the temperature in the reaction kettle at 40-60 ℃, slowly adding a small amount of concentrated sulfuric acid catalyst into the macromonomer obtained in the step I under the stirring state, continuously dropwise adding phosphoric acid into the kettle for esterification reaction, heating to 85-105 ℃ after all dropwise adding is finished, continuously keeping the temperature for reaction for 20-60 minutes, cooling and discharging when the pH is 5.00-7.00 through a central control test, and obtaining the ester macromonomer product.

2. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1, which is characterized by comprising the following steps: the initiation dosage of the propylene oxide in the step I is not more than 20 percent of the total feeding dosage of the propylene oxide.

3. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1 or 2, characterized by comprising the following steps: the mass ratio of the propylene oxide to the ethylene oxide in the step I is 1: 3.0-9.0.

4. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1 or 2, characterized by comprising the following steps: the dosage of the alkaline catalyst in the step I is 0.03-0.20% of the total feeding amount.

5. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1 or 2, characterized by comprising the following steps: the mass ratio of the 4-phenyl-1-butylene-4-alcohol to the epoxide in the reaction in the step I is 1:2.38-9.14, and the molecular weight of the macromonomer product is 500-1500; the above epoxides include propylene oxide and ethylene oxide.

6. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1 or 2, characterized by comprising the following steps: the alkaline catalyst in the step I is alkali metal, alkali metal hydroxide, alkali metal hydride, alkaline earth metal hydroxide, alkali metal alkoxide, alkaline earth metal oxide, organic alkaline catalyst or two or more of the alkali metal, the alkali metal hydroxide, the alkali metal hydride, the alkaline earth metal hydroxide, the alkali metal alkoxide, the alkaline earth metal oxide and the organic alkaline catalyst; wherein the alkali metal is sodium and potassium; the alkali metal hydroxide is potassium hydroxide, sodium hydroxide or lithium hydroxide; the alkali metal hydrides are: sodium hydride, potassium hydride; the hydroxide of the alkaline earth metal is magnesium hydroxide and calcium hydroxide; alkali metal alkoxide is sodium methoxide, sodium ethoxide, potassium methoxide, or potassium glycerolate; the oxide of alkaline earth metal is magnesium oxide and calcium oxide; the organic base catalyst is ethanolamine, diethanolamine, triethanolamine, dimethylamine, trimethylamine, diethylamine and triethylamine.

7. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1 or 2, characterized by comprising the following steps: the amount of the propylene oxide introduced in the step I is 10 to 25 percent of the total feeding amount of the epoxide; the above amounts of propylene oxide include the initiating amount; the above epoxides include propylene oxide and ethylene oxide.

8. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1 or 2, characterized by comprising the following steps: secondly, the dosage of the concentrated sulfuric acid catalyst is 0.05 to 0.10 percent of the total mass of the raw materials; the molar ratio of the macromonomer to the phosphorus-containing acid is 1: 0.80-1.00.

9. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1 or 2, characterized by comprising the following steps: in the second step, the phosphoric acid is one or more mixed acids of phosphoric acid, metaphosphoric acid, phosphorous acid, hypophosphorous acid and pyrophosphoric acid.

10. The preparation method of the ester macromonomer for a super-retarding polycarboxylate superplasticizer according to claim 1 or 2, characterized by comprising the following steps: in the second step, the molecular weight of the final product ester macromonomer is 500-1600.

One, the technical field

The invention belongs to the technical field of synthesis of polycarboxylate superplasticizer monomers, and particularly relates to a preparation method of an ester macromonomer for a super-slow-coagulation polycarboxylate superplasticizer.

Second, background Art

The polycarboxylic acid high-performance water reducing agent is a third-generation high-performance water reducing agent, has the characteristics of low mixing amount, high water reducing rate, no segregation, high slump loss resistance and the like compared with the first two-generation water reducing agents, is a specified additive for high-speed rails, bridges, landmarks and important key projects in China, and meets another high-speed development opportunity. In large-scale bridge engineering, in order to improve the bearing capacity of a single pile, the length and the cross section of the pile are large, the volume of concrete needed to be poured into the single pile is large, the pouring time is long, especially in hot summer, the initial setting time of the concrete needs to be greatly prolonged, and in some summer, the initial setting time needs to be prolonged for more than ten hours or even more, so that the successful primary pouring can be ensured, and the concrete needs to be prepared by adopting a super-retarding polycarboxylic acid water reducing agent.

Heretofore, the preparation of the super-retarding polycarboxylate superplasticizer mainly adopts the following two ways: firstly, when a polycarboxylate water reducing agent or a pumping aid is compounded, a large amount of auxiliary agents with a retarding function are added to enable the compound to have a super retarding function, the process is physical mixing, and used raw materials such as gluconate, phosphate, lignosulfonate and the like are used; secondly, a basic raw material with a retarding structure, such as organic phosphonic acid, is added in the process of synthesizing the polycarboxylic acid water reducing agent. In the patent ZL201310177835, an unsaturated phosphonic acid copolymer is used for participating in polymerization reaction, so that a polycarboxylic acid water reducer has a super-retarding function; for example, CN201711289700.7, uses hydroxyethylidene diphosphonic acid and/or 2-hydroxyphosphonoacetic acid structure to participate in polymerization reaction.

The polycarboxylate superplasticizer macromonomer is a main raw material for synthesizing a polycarboxylate high-performance water reducer, and no polycarboxylate superplasticizer macromonomer optimizes a functional product integrating high water reducing performance and super-retarding performance through molecular structure design so far. The existing large monomer of the polycarboxylic acid water reducer is usually of an ether structure, unsaturated alcohol is used as an initiator, such as allyl alcohol and homologs thereof, isopentenol, unsaturated six-carbon alcohol ether and the like, and the large monomer is polymerized with epoxide to prepare the polycarboxylic acid water reducer, and the polycarboxylic acid water reducer prepared by using the large monomer polyether synthesized by the raw materials only has the functions of reducing water and preventing slump; and a small amount of acrylate macromonomer, which is an ester prepared only for introducing a double bond into polyethylene glycol monomethyl ether, has the same function as the ether structure.

Third, the invention

The invention aims to provide a preparation method of an ester macromonomer for a super-retarding polycarboxylate superplasticizer.

In order to achieve the purpose, the invention adopts the technical scheme that: the method comprises the following steps:

synthesis of a macromonomer: adding 4-phenyl-1-butene-4-ol into a reaction kettle, and simultaneously adding a small amount of alkaline catalyst; after introducing high-purity nitrogen for replacement, keeping the initiation temperature in the reaction kettle at 110-; after the reaction is successfully initiated, increasing the reaction temperature T to 130-; continuously introducing ethylene oxide into the reaction kettle, curing for 1 hour after the feeding is finished, and degassing after curing to obtain a macromonomer;

② esterification end capping of macromonomer: keeping the temperature in the reaction kettle at 40-60 ℃, slowly adding a small amount of concentrated sulfuric acid catalyst into the macromonomer obtained in the step I under the stirring state, continuously dropwise adding phosphoric acid into the kettle for esterification reaction, heating to 85-105 ℃ after all dropwise adding is finished, continuously carrying out heat preservation reaction for 20-60 minutes, cooling and discharging when the pH is 5.00-7.00 through a central control test, and obtaining the ester macromonomer product.

The initiation dosage of the propylene oxide in the step I is not more than 20 percent of the total feeding dosage of the propylene oxide.

The mass ratio of the propylene oxide to the ethylene oxide in the step (i) is 1:3.0-9.0, preferably 1: 4.0-5.6.

The dosage of the alkaline catalyst in the step I is 0.03-0.20% of the total feeding amount, and preferably 0.05-0.11% of the total feeding amount.

The mass ratio of the 4-phenyl-1-butene-4-ol to the epoxide in the reaction in the step (i) is 1:2.38-9.14, the molecular weight of the macromonomer product is 500-1500, and the mass ratio of the 4-phenyl-1-butene-4-ol to the epoxide is preferably 1: 4.74-7.11; the molecular weight of the macromonomer product is 850-; the above epoxides include propylene oxide and ethylene oxide.

The alkaline catalyst in the step I is alkali metal, alkali metal hydroxide, alkali metal hydride, alkaline earth metal hydroxide, alkali metal alkoxide, alkaline earth metal oxide, organic alkaline catalyst or two or more of the alkali metal, the alkali metal hydroxide, the alkali metal hydride, the alkaline earth metal hydroxide and the organic alkaline catalyst; wherein the alkali metal is sodium and potassium; the alkali metal hydroxide is potassium hydroxide, sodium hydroxide or lithium hydroxide; the alkali metal hydrides are: sodium hydride, potassium hydride; the hydroxide of the alkaline earth metal is magnesium hydroxide and calcium hydroxide; alkali metal alkoxide is sodium methoxide, sodium ethoxide, potassium methoxide, or potassium glycerolate; the alkaline earth metal oxide is magnesium oxide and calcium oxide; the organic base catalyst is ethanolamine, diethanolamine, triethanolamine, dimethylamine, trimethylamine, diethylamine and triethylamine.

The amount of the propylene oxide introduced in the step I is 10 to 25 percent of the total feeding amount of the epoxide; the above amounts of propylene oxide include the initiating amount; the above epoxides include propylene oxide and ethylene oxide.

Secondly, the dosage of the concentrated sulfuric acid catalyst is 0.05 to 0.10 percent of the total mass of the raw materials; the molar ratio of macromonomer to phosphorus-containing acid is 1:0.80 to 1.00, preferably 1:0.95 to 1.00.

In the second step, the phosphoric acid is one or more mixed acids of phosphoric acid, metaphosphoric acid, phosphorous acid, hypophosphorous acid and pyrophosphoric acid.

In the step (II), the molecular weight of the final product ester macromonomer is 500-1600, and the preferred molecular weight is 900-1250.

The invention has the following advantages:

1. the invention adopts 4-phenyl-1-butylene-4-alcohol with a new structure as an initiator, and is completed by block polymerization of a specific epoxide and esterification and end capping. The ester macromonomer prepared by the method and the polycarboxylic acid water reducing agent further prepared by the ester macromonomer have excellent application performance, and are the core technology of the invention.

2. The polycarboxylate superplasticizer synthesized by the ester macromonomer prepared by the invention has the functions of high water reduction, slump retention and super-retarding in a monomer structure on a molecular branch chain, namely, the polycarboxylate superplasticizer has the function of super-retarding while keeping the original function of the polycarboxylate superplasticizer, so that the application of the super-retarding polycarboxylate superplasticizer in the field of concrete is promoted more widely, and the polycarboxylate superplasticizer is particularly applied more widely in specific engineering.

3. The raw materials used in the invention are easily available and are common chemical products. The production raw materials are all converted into the final product, and the production process does not generate three wastes, thereby being a clean and green process.

4. The equipment used by the invention is only a conventional reaction kettle and a pump, and can be realized without high investment and high maintenance cost, thereby improving the economic benefit.

Fourth, detailed description of the invention