阅读说明：本技术 一种乙烯基聚醚大单体的合成方法 (Synthesis method of vinyl polyether macromonomer ) 是由 范士敏 牟中江 迟国福 李新全 于 2020-07-31 设计创作，主要内容包括：本发明公开了一种乙烯基聚醚大单体的合成方法,包括烷氧基聚醚大单体制备和乙烯基聚醚大单体制备,以烷基醇和环氧烷烃为原料,在催化剂作用下,在一定温度和压力条件下开环聚合,得到烷氧基聚醚大单体,向烷氧基聚醚大单体中加入阻聚剂,在一定温度和压力条件下,向烷氧基聚醚大单体中加入乙炔,反应结束后减压蒸馏出挥发性组分,得到乙烯基聚醚大单体。本发明一方面将催化剂全部转化为活性更高的聚醚醇钾/钠盐；另一方面通过开环聚合将烷基醇变为分子量更大和溶解性更好的烷氧基聚醚,促进催化剂在反应体系中完全溶解,更好的发挥均相催化的催化效率。(The invention discloses a method for synthesizing vinyl polyether macromonomer, which comprises the preparation of alkoxy polyether macromonomer and the preparation of vinyl polyether macromonomer, wherein alkyl alcohol and alkylene oxide are used as raw materials, ring opening polymerization is carried out under the action of a catalyst and under the condition of certain temperature and pressure to obtain alkoxy polyether macromonomer, polymerization inhibitor is added into the alkoxy polyether macromonomer, acetylene is added into the alkoxy polyether macromonomer under the condition of certain temperature and pressure, and volatile components are distilled out under reduced pressure after the reaction is finished to obtain the vinyl polyether macromonomer. On one hand, the catalyst is completely converted into polyether alcohol potassium/sodium salt with higher activity; on the other hand, alkyl alcohol is changed into alkoxy polyether with larger molecular weight and better solubility through ring-opening polymerization, so that the catalyst is promoted to be completely dissolved in a reaction system, and the catalytic efficiency of homogeneous catalysis is better exerted.)

1. A method for synthesizing vinyl polyether macromonomer is characterized by comprising the following steps:

(1) preparation of alkoxy polyether macromonomer:

taking alkyl alcohol and alkylene oxide as raw materials, and performing ring opening polymerization under certain temperature and pressure conditions under the action of a catalyst to obtain an alkoxy polyether macromonomer;

(2) preparation of vinyl polyether macromonomer:

adding a polymerization inhibitor into the alkoxy polyether macromonomer in the step (1), adding acetylene into the alkoxy polyether macromonomer under certain temperature and pressure conditions, and distilling out volatile components under reduced pressure of-0.1 MPa after the reaction is finished to obtain the vinyl polyether macromonomer.

2. The method of claim 1, wherein one of the alkoxy polyether macromonomer has the formula (1);

wherein R is¹The alkyl group with the number of carbon atoms of 1-10, such as methyl, ethyl, isopropyl, butyl, n-hexyl, cyclohexyl, isooctyl and the like; r²Is one of hydrogen and methyl; y is the number of ethylene oxide structural units and is an integer between 20 and 100; x is the number of structural units of propylene oxide and is an integer between 0 and 10, and the ratio of x/y is less than or equal to 0.1.

3. The method of claim 1, wherein the alkyl alcohol in step (1) comprises one of the alkyl alcohols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol monoisooctyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether.

4. The method of claim 1, wherein the alkylene oxide in step (1) comprises one or two of ethylene oxide and propylene oxide, and the reaction of the alkyl alcohol with the alkylene oxide in step (1) can be block polymerization or random polymerization.

5. The method of claim 1, wherein the catalyst in step (1) comprises one of sodium hydroxide, sodium metal, sodium hydride, sodium methoxide, potassium hydroxide, potassium methoxide, or potassium tert-butoxide, and the amount of the catalyst is 10-20% of the mass of the alkyl alcohol.

6. The method for synthesizing vinyl polyether macromonomer according to claim 1, wherein in step (1), the reaction temperature is 100-120 ℃ and the reaction pressure is less than or equal to 0.4 MPa.

7. The method of claim 2, wherein in the step (2), one of the vinyl polyether macromonomers has a structural formula shown in the following formula (2):

wherein R is¹The alkyl group with the number of carbon atoms of 1-10, such as methyl, ethyl, isopropyl, butyl, n-hexyl, cyclohexyl, isooctyl and the like; r²Is one of hydrogen and methyl; y is the number of ethylene oxide structural units and is an integer between 20 and 100; x is the number of structural units of propylene oxide and is an integer between 0 and 10, and the ratio of x/y is less than or equal to 0.1.

8. The method for synthesizing vinyl polyether macromonomer according to claim 2, wherein a polymerization inhibitor is added before the alkoxy polyether macromonomer reacts with acetylene in step (2), the amount of the polymerization inhibitor is 0.001-0.005% of the mass of the alkoxy polyether macromonomer, and the polymerization inhibitor comprises one of hydroquinone, p-benzoquinone, phenothiazine, p-tert-butylcatechol, and the like.

9. The method for synthesizing vinyl polyether macromonomer according to claim 2, wherein in the step (2), the alkoxy polyether macromonomer is reacted with acetylene, the molar ratio of acetylene to the alkoxy polyether macromonomer is (1.1-2.0): 1, the reaction temperature is 170-200 ℃, the reaction pressure is 0.3-0.7 MPa, nitrogen is used as a way of increasing the pressure in the reaction kettle, and the reaction time of acetylene feeding is 10-24 h.

10. The method for synthesizing the vinyl polyether macromonomer according to claim 2, wherein the alkoxy polyether macromonomer reacts with acetylene in the step (2), the reaction is continued for 0.5h under heat preservation after the acetylene feeding is finished, the temperature is reduced to 50-70 ℃, volatile components are distilled out under reduced pressure, and brown yellow viscous liquid, namely the vinyl polyether macromonomer, is obtained.

Technical Field

The invention relates to a method for synthesizing vinyl polyether macromonomer, in particular to a method for synthesizing vinyl polyether macromonomer, belonging to the field of concrete admixture application.

Background

Concrete is widely applied to various fields as a building material and is formed by mixing cement, gravel aggregate, water and a concrete additive, wherein the concrete additive is an essential component in the concrete, can adjust and improve the working performance of the concrete material and plays a central role in the concrete production technology. The water reducing agent is a concrete admixture with the largest concrete dosage and the most extensive application, in particular to a third-generation high-performance polycarboxylic acid water reducing agent, has high water reducing rate and good slump retaining performance, is widely applied to the concrete industry, and accounts for more than 80 percent of the market share of the water reducing agent.

The polycarboxylate superplasticizer synthesized by polyether macromonomer taking methyl allyl alcohol and 3-methyl-3-butylene-1-alcohol as initiators is sensitive to the clay and stone powder content in sandstone aggregate, and along with the reduction of natural high-quality sandstone aggregate resources and the application of industrial waste residues and machine-made sandstone in commercial concrete, the application problems of large fluctuation of water reducing performance, poor slump loss resistance and the like of the polycarboxylate superplasticizer are more and more prominent. Research and development find that the polycarboxylic acid water reducing agent prepared by using hydroxyl-containing vinyl ether such as ethylene glycol vinyl ether, diethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether and the like as an initiator has certain advantages in the aspects of mud resistance, stone powder resistance and the like.

Lei Lei et al found that the polycarboxylic acid water reducing agent synthesized by using a polyether macromonomer prepared by using 4-hydroxybutyl vinyl ether as an initiator is superior to the polycarboxylic acid water reducing agent synthesized by allyl alcohol, methyl allyl alcohol and 3-methyl-3-butene-1-ol in the dispersing ability and clay tolerance of the water reducing agent, (Lei Lei, Johann plant.

In the Wenxiang et al, 4-hydroxybutyl vinyl polyoxyethylene ether is used as a polyether macromonomer, and a low-sensitivity polycarboxylate water reducer is synthesized, has low doping amount sensitivity, low temperature sensitivity and low water consumption sensitivity, and has a good application effect in machine-made sand and low-grade concrete (in the Wenxiang et al, the research and evaluation of the low-sensitivity polycarboxylate water reducer [ J ] novel building materials, 2019,46(11):30-32+ 54).

The performance research of the polycarboxylic acid water reducing agent shows that the hydroxyl-containing vinyl ether represented by 4-hydroxybutyl vinyl ether is used as an initiator, and the polycarboxylic acid water reducing agent has certain performance advantages on a polyether macromonomer obtained by ring-opening polymerization of ethylene oxide. At present, hydroxyl-containing vinyl ether is mainly synthesized by an acetylene method, acetylene, ethylene glycol, diethylene glycol, 1, 4-butanediol and the like are used as raw materials to perform catalytic addition reaction under certain pressure and temperature conditions, and after the reaction is finished, the raw materials are rectified, separated and purified to obtain the hydroxyl-containing monovinyl ether.

Zhang Jibo et al [ research on continuous synthesis process of diethylene glycol vinyl ether [ J ], proceedings of Jilin chemical academy of Industrial science, 2012,29(3),20-23] use diethylene glycol and acetylene as raw materials, use fixed bed reactor and gas-liquid heterogeneous reaction process, synthesize diethylene glycol vinyl ether continuously, the yield is about 46%; meanwhile, the yield of the diethylene glycol divinyl ether byproduct is about 26%, and the total yield is about 72%.

Patent CN 102173982B reports a synthesis method of ethylene glycol vinyl ether and ethylene glycol divinyl ether. Acetylene and ethylene glycol are used as raw materials, firstly, ethylene glycol, potassium hydroxide and polyethylene glycol dimethyl ether are mixed to prepare a potassium alkoxide solution, then zinc oxide, triphenylphosphine and the like are added and uniformly mixed to serve as a base solution, a reaction kettle is heated to 80-200 ℃, acetylene is introduced, and after the reaction is finished, reduced pressure distillation is carried out to obtain ethylene glycol vinyl ether and ethylene glycol divinyl ether crude products.

Patent CN103394371A reports a synthesis method of 4-hydroxybutyl vinyl ether. Taking 1, 4-butanediol potassium alcoholate and 1, 4-butanediol as base solutions, controlling the reaction temperature to be 80-150 ℃, introducing acetylene for reaction, and after the reaction is finished, transferring the reaction product into a rectifying tower for rectification to obtain the 4-hydroxybutyl vinyl ether.

The acetylene process reported in the above documents and patents is currently an industrial process. Acetylene reacts with a diol monomer, but potassium hydroxide, potassium alkoxide and the like are used as a catalyst, the amount of the catalyst is generally 2 to 5 percent, the molecular weight of the diol monomer is small, and particularly for hydrophobic diol monomers, the compatibility between the catalyst and the diol monomer is not particularly good, so that the catalytic efficiency is reduced; on the other hand, the reaction product of acetylene and diol monomer is monovinyl ether and by-product divinyl ether, and further rectification, separation and purification are required. Because the boiling ranges of the hydroxyl-containing monovinyl ether and the hydroxyl-containing divinyl ether are not different greatly (generally between 5 and 10 ℃), the difference of the boiling ranges of the two components is further reduced under the condition of vacuum rectification, so that the rectification separation and purification time is long and the energy consumption is high. In addition, the research and development of gazel and the like find that the polyether macromonomer with the methyl-terminated end has high conversion rate and the prepared polycarboxylate water reducer has good water reducing rate and slump retaining performance (the preparation of the methoxy polyethylene glycol allyl-terminated polyether and the application thereof in the cement water reducer [ A ]; the national Special concrete technology and engineering application academy and the 2008 year concrete quality Special Committee annual meeting statement [ C ]: 2008 year).

Based on the method, the invention provides a method for directly preparing vinyl polyether macromonomer, avoids the problems of by-products and rectification and purification in the process of synthesizing hydroxyl-containing monovinyl ether, and has the advantages of obvious technical advancement, energy conservation, consumption reduction and the like.

Disclosure of Invention

The present invention has been made to solve the above problems, and an object of the present invention is to provide a method for synthesizing a vinyl polyether macromonomer.

The invention achieves the aim through the following technical scheme, and the synthesis method of the vinyl polyether macromonomer comprises the following steps:

(1) preparation of alkoxy polyether macromonomer:

taking alkyl alcohol and alkylene oxide as raw materials, and performing ring opening polymerization under certain temperature and pressure conditions under the action of a catalyst to obtain an alkoxy polyether macromonomer;

(2) preparation of vinyl polyether macromonomer:

adding a polymerization inhibitor into the alkoxy polyether macromonomer in the step (1), adding acetylene into the alkoxy polyether macromonomer under certain temperature and pressure conditions, and distilling out volatile components under reduced pressure after the reaction is finished to obtain the vinyl polyether macromonomer.

Preferably, one structural formula of the alkoxy polyether macromonomer is shown as the following formula (1);

wherein R is¹Is methyl, ethyl, isopropyl, butyl, n-hexyl, cyclohexyl, isooctyl and other carbon atoms1-10 alkyl groups; r²Is one of hydrogen and methyl; y is the number of ethylene oxide structural units and is an integer between 20 and 100; x is the number of structural units of propylene oxide and is an integer between 0 and 10, and the ratio of x/y is less than or equal to 0.1.

Preferably, the alkyl alcohol in step (1) includes one of alkyl alcohols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol monoisooctyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether.

Preferably, the alkylene oxide in step (1) includes one or two of ethylene oxide, propylene oxide and other alkylene oxides, and in the reaction of the alkyl alcohol and the alkylene oxide in step (1), the ethylene oxide and the propylene oxide may be block polymerization or random polymerization.

Preferably, the catalyst in step (1) comprises one of sodium hydroxide, metallic sodium, sodium hydride, sodium methoxide, potassium hydroxide, potassium methoxide or potassium tert-butoxide, and the amount of the catalyst is 10-20% of the mass of the alkyl alcohol.

Preferably, the reaction temperature in the step (1) is between 100 and 120 ℃, and the reaction pressure is less than or equal to 0.4 MPa.

Preferably, the vinyl polyether macromonomer in step (2), one of the structural formulas is represented by the following formula (2):

wherein R is¹The alkyl group with the number of carbon atoms of 1-10, such as methyl, ethyl, isopropyl, butyl, n-hexyl, cyclohexyl, isooctyl and the like; r²Is one of hydrogen and methyl; y is the number of ethylene oxide structural units and is an integer between 20 and 100; x is the number of structural units of propylene oxide and is an integer between 0 and 10, and the ratio of x/y is less than or equal to 0.1.

Preferably, a polymerization inhibitor is added before the alkoxy polyether macromonomer reacts with acetylene in the step (2), the dosage of the polymerization inhibitor is 0.001-0.005% of the mass of the alkoxy polyether macromonomer, and the polymerization inhibitor comprises one of hydroquinone, p-benzoquinone, phenothiazine, p-tert-butylcatechol and the like.

Preferably, in the step (2), the alkoxy polyether macromonomer is reacted with acetylene, the molar ratio of acetylene to the alkoxy polyether macromonomer is (1.1-2.0): 1, the reaction temperature is 170-200 ℃, the reaction pressure is 0.3-0.7 MPa, nitrogen is used as a mode for increasing the pressure in the reaction kettle, and the reaction time of acetylene feeding is 10-24 h.

Preferably, the alkoxy polyether macromonomer reacts with acetylene in the step (2), after the acetylene feeding is finished, the reaction is continued for 0.5 hour under heat preservation, the temperature is reduced to 50-70 ℃, volatile components are distilled out under reduced pressure, and a brown yellow viscous liquid, namely the vinyl polyether macromonomer, is obtained.

The invention has the beneficial effects that: the invention provides a preparation method of vinyl polyether macromonomer, which is simple in preparation method, strong in structure adjustability and less in by-product.

Specifically, the vinyl polyether macromonomer reported by the invention has the following advantages:

(1) according to the invention, through the ring-opening polymerization reaction of alkyl alcohol and ethylene oxide, on one hand, all the catalyst is converted into polyether alcohol potassium salt with higher activity; on the other hand, alkyl alcohol is changed into alkoxy polyether with larger molecular weight and better solubility through ring-opening polymerization, so that the catalyst is promoted to be completely dissolved in a reaction system, and the catalytic efficiency of homogeneous catalysis is better exerted.

(2) The vinyl polyether macromonomer is prepared by reacting the alkoxy polyether macromonomer with only one hydroxyl at the tail end with acetylene, so that the problems of reaction selectivity and rectification purification of a generated divinyl ether byproduct are solved, and the monovinyl ether macromonomer can be prepared more conveniently.

(3) One end of the vinyl polyether macromonomer is a vinyl double bond, and the other end of the vinyl polyether macromonomer is an alkoxy end capping; compared with the conventional williamson etherification reaction for polyether macromonomer end capping, the method disclosed by the invention has no etherification side reaction problems of chlorinated waste salt and chlorinated hydrocarbon.

Detailed Description

The present invention is described in detail below by way of examples, which are intended to be illustrative only and not to be construed as limiting the scope of the invention, and one skilled in the art will be able to make variations within the scope of the invention based on the disclosure herein, in reagents, catalysts and reaction process conditions. All equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

All chemical reagents in the invention are commercial industrial grade purity products, and the raw materials are measured in parts by mass.

The molecular weight of the alkoxy polyether macromonomer is tested by referring to a hydroxyl value method recommended in JC/T2033-2018 polyether for concrete admixture and derivatives thereof, and the effective content of the polyether macromonomer is tested by a high performance liquid test method reported in a reference document (Xiliana and the like, high performance liquid chromatography is used for measuring the mass fraction [ J ],2016,33(6) and 53-60) of polyethylene glycol in the polycarboxylic acid water reducer macromonomer).

A method for synthesizing vinyl polyether macromonomer comprises the following steps:

(1) preparation of alkoxy polyether macromonomer:

taking alkyl alcohol and alkylene oxide as raw materials, and performing ring opening polymerization under certain temperature and pressure conditions under the action of a catalyst to obtain an alkoxy polyether macromonomer;

(2) preparation of vinyl polyether macromonomer:

adding a polymerization inhibitor into the alkoxy polyether macromonomer in the step (1), adding acetylene into the alkoxy polyether macromonomer under certain temperature and pressure conditions, and distilling out volatile components under reduced pressure after the reaction is finished to obtain the vinyl polyether macromonomer.

In the reaction of the alkyl alcohol and the alkylene oxide in the step (1), on one hand, the molecular weight and the mass ratio of the alkyl alcohol are improved through ring-opening polymerization, the mass ratio of the catalyst is reduced, and the solubility of the catalyst is improved; on the other hand, the catalyst is converted into alcohol potassium salt of polyether macromonomer with higher activity by ring-opening polymerization.

In the reaction of the alkoxy polyether macromonomer and acetylene in the step (2), because the alkoxy polyether macromonomer only has one terminal hydroxyl group, only monovinyl ether and a small amount of cyclic acetal byproducts can be generated in the reaction process of the alkoxy polyether macromonomer and acetylene, and the reaction is basically free of bi-vinyl ether byproducts, so that the acetylene consumption with high economic value is saved, the separation of the monovinyl ether and the byproducts is easier to realize, and the energy-saving effect is obvious.

One structural formula of the alkoxy polyether macromonomer is shown as the following formula (1);

wherein R is¹The alkyl group with the number of carbon atoms of 1-10, such as methyl, ethyl, isopropyl, butyl, n-hexyl, cyclohexyl, isooctyl and the like; r²Is one of hydrogen and methyl; y is the number of ethylene oxide structural units and is an integer between 20 and 100; x is the number of structural units of propylene oxide and is an integer between 0 and 10, and the ratio of x/y is less than or equal to 0.1.

The alkyl alcohol in the step (1) comprises one of alkyl alcohols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol monoisooctyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether and diethylene glycol monobutyl ether.

The alkylene oxide in the step (1) comprises one or two of ethylene oxide, propylene oxide and other alkylene oxides, and in the reaction of the alkyl alcohol and the alkylene oxide in the step (1), the ethylene oxide and the propylene oxide can be block polymerization or random polymerization.

The catalyst in the step (1) comprises one of sodium hydroxide, metal sodium, sodium hydride, sodium methoxide, potassium hydroxide, potassium methoxide or potassium tert-butoxide and the like, and the dosage of the catalyst is 10-20% of the mass of the alkyl alcohol.

In the step (1), the reaction temperature is 100-120 ℃, and the reaction pressure is less than or equal to 0.4 MPa.

The vinyl polyether macromonomer in the step (2), wherein one structural formula is shown as the following formula (2):

wherein R is¹The alkyl group with the number of carbon atoms of 1-10, such as methyl, ethyl, isopropyl, butyl, n-hexyl, cyclohexyl, isooctyl and the like; r²Is one of hydrogen and methyl; y is the number of ethylene oxide structural units and is an integer between 20 and 100; x is the number of structural units of propylene oxide and is an integer between 0 and 10, and the ratio of x/y is less than or equal to 0.1.

And (3) adding a polymerization inhibitor before the alkoxy polyether macromonomer reacts with acetylene in the step (2), wherein the dosage of the polymerization inhibitor is 0.001-0.005% of the mass of the alkoxy polyether macromonomer, and the polymerization inhibitor comprises one of hydroquinone, p-benzoquinone, phenothiazine, p-tert-butylcatechol and the like.

And (3) reacting the alkoxy polyether macromonomer with acetylene in the step (2), wherein the molar ratio of acetylene to the alkoxy polyether macromonomer is (1.1-2.0): 1, the reaction temperature is 170-200 ℃, the reaction pressure is 0.3-0.7 MPa, nitrogen is used as a mode for increasing the pressure in the reaction kettle, and the acetylene feeding reaction time is 10-24 h.

And (3) reacting the alkoxy polyether macromonomer with acetylene in the step (2), continuing to perform heat preservation reaction for 0.5h after the acetylene feeding is finished, cooling to 50-70 ℃, and performing reduced pressure distillation to obtain a volatile component to obtain a brown yellow viscous liquid, namely the vinyl polyether macromonomer.