CN100523019C - Alkali thickening type rheological modifier and its preparing method - Google Patents

Abstract

The invention discloses an alkali-thickening rheology modifier, which is composed of unsaturated carboxylic acid containing carbon-carbon double bonds, macromonomers containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains, Agents, crosslinking agents, chain transfer agents, etc. are polymerized in organic solvents. Due to the introduction of reactive macromonomers containing long hydrocarbon chains and polyoxyethylene chains, the reaction in the polymerization process is stable, and the product is a loose powder that is easily dispersed in water. After neutralization with alkali, the viscosity can be rapidly increased to improve the rheology of the solution. Since the polymer of the present invention does not add other surfactants as dispersion stabilizers during the synthesis process, the polymer product will not be polluted by other surfactants, and will not be easily attacked by microorganisms. This rheology modifier can effectively increase the viscosity of water, polyol or polyol and water mixed solution at low shear rate at a very low concentration, endowing the solution with good shear thinning performance.

Description

Alkali thickening type rheology modifier and preparation method thereof

technical field

The invention relates to a rheology modifier and a preparation method thereof, in particular to a method for improving the rheological properties of water, polyalcohol and the mixed solution of polyalcohol and water, and can effectively improve its performance in low shear Alkali-thickening rheology modifier with viscosity at high speed and its preparation method.

Background technique

In order to change the rheological properties and viscosity of water, polyol and the mixed solution of polyol and water, it is often necessary to add a rheology modifier (customarily called a thickener) to the system. Among the commonly used rheology modifiers, natural products include guar gum, xanthan gum, etc.; synthetic products include polyacrylic acid and polyacrylamide. The following is a brief description of the alkali thickening type rheology modifier and its synthesis aspect disclosed in the patent literature at present:

US 6,433,061 discloses a chain transfer agent containing a hydrophobic chain, a steric stabilizer, and an allyl sucrose ether with a carbon-carbon double bond unsaturated carboxylic acid, dodecyl mercaptan, etc. as a crosslinking agent. Acrylates with long carbon chains are used as cross-linked polymers synthesized from hydrophobic monomers to increase the viscosity of aqueous solutions containing electrolytes. This patented technology uses allyl sucrose ether as a cross-linking agent to improve the thickening ability, but this cross-linking agent made of sucrose is vulnerable to bacterial attack in water, causing mildew and destroying product quality; in addition, this patented technology also Using steric surfactants as dispersion stabilizers, these surfactants will remain in subsequent products, which may limit the use of the final product.

CN 1424335 discloses a kind of preparation method of acrylate thickener. It uses monomers, emulsifiers, initiators, etc. commonly used in the synthesis of acrylate thickeners as raw materials, and is carried out in supercritical carbon dioxide. Due to the high reaction pressure, the safety risk of actual operation is increased.

CN 1415658 discloses a method for preparing an associative thickener containing fluorocarbon hydrophobic groups. This thickener is a polymer synthesized from acrylic or methacrylic acid, fluorinated acrylate or methacrylate, and a bifunctional crosslinking agent. Due to the high price of fluorinated acrylates, the cost of the polymer is high.

US 6437068 discloses a water-soluble or water-swellable polymer synthesized in t-butyl alcohol by acrylamido alkyl sulfonate, N-vinylamide monomer and crosslinking agent. US 6645476 discloses a polymer synthesized by acrylamido alkyl sulfonate and macromonomers containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains. Since the above two polymer monomers have been neutralized during the synthesis process, the resulting product can be directly thickened in water, which is not conducive to the uniform mixing of other materials in the system.

Contents of the invention

The object of the present invention is to provide an alkali-thickening rheology modifier capable of effectively improving the rheological properties and viscosity of water, polyol and the mixed solution of polyol and water and its preparation method. The rheology modifier can not only effectively improve the viscosity and shear thinning performance of water, polyol and the mixed solution of polyol and water at a low shear rate, but also increase the adhesion of the solution on an inclined surface. When used in oil-water mixed systems and liquid-solid mixed systems, it can also improve the stability of oil-water mixtures and increase the suspension stability of solids in solutions.

The purpose of the present invention is achieved by adopting the following technical solutions:

An alkali thickening type rheology modifier is characterized in that it comprises the following components polymerized in an organic solvent by weight ratio:

50-95 parts of unsaturated carboxylic acid containing carbon-carbon double bond

1-40 parts of macromonomers containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains

Initiator 0.1～2 parts

Cross-linking agent 0.01～5 parts

Chain transfer agent 0.05~4 parts

Wherein, the preferred range value of the above components is:

60-90 parts of unsaturated carboxylic acid containing carbon-carbon double bond,

5-30 parts of macromonomers containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains

Initiator 0.5～1 part

0.1-2 parts of cross-linking agent

Chain transfer agent 0.1~2 parts

Described organic solvent comprises: sherwood oil, solvent naphtha, ethyl acetate, butyl acetate, isobutyl acetate, toluene, xylene, benzene, cyclohexane, decahydronaphthalene, n-octane, isooctane, and these mixture of solvents.

The amount of the organic solvent used is 2 to 20 times the total weight of the monomers of the above components, usually more likely to be 3 to 10 times.

The unsaturated carboxylic acid containing carbon-carbon double bonds is composed of one or more monobasic or polybasic acids containing 3 to 13 carbon atoms.

These unsaturated carboxylic acids containing carbon-carbon double bonds include: acrylic acid, methacrylic acid, α-cyanoacrylic acid, crotonic acid, butenedioic acid, itaconic acid and the like. The carboxylic acid mentioned here also includes maleic anhydride and the like which can be hydrolyzed into carboxylic acid.

In particular, the unsaturated carboxylic acid containing carbon-carbon double bonds is preferably acrylic acid, methacrylic acid or a mixture of the two in any proportion.

The molecular structure of the macromonomer containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains is A-B-C, and the A, B, and C groups are connected by chemical bonds, wherein

The structure of the A group is:

R ₁ ——

R ₁ is a hydrocarbon chain containing 8 to 30 carbons.

The structure of the B group is:

m is 1~60

The structure of the C group is:

The structure formed by the reaction of monomers containing carbon-carbon double bonds and active groups with polyoxyethylene with a long carbon-hydrogen chain at one end, that is, unsaturated carboxylic acids containing carbon-carbon double bonds or their anhydrides and acid halides , ester, and the structure formed by the reaction of isocyanate containing carbon-carbon double bond and hydroxyl group at the end of polyoxyethylene.

in,

Monomers containing carbon-carbon double bonds and active groups are: (meth)acrylic acid, (meth)acryloyl halide, (meth)acrylic anhydride, maleic anhydride, (meth)methyl acrylate, (meth) Base) ethyl acrylate, butyl (meth)acrylate, isopropyl (meth)acrylate, etc. These monomers react with polyoxyethylene containing hydroxyl and long carbon hydrogen chains to form ester macromonomers.

Isocyanate monomers containing carbon-carbon double bonds are: 1, 1-dimethyl-3-isopropenylphenyl methyl isocyanate, methacrylic acid-2-isocyanate ethyl, etc., such monomers pass The isocyanate groups react with polyoxyethylene containing hydroxyl groups and long hydrocarbon chains to form macromonomers with a urethane-like chemical structure.

The initiator described in the present invention initiates the polymerization reaction by the free radical formed by decomposition, including: dilauroyl peroxide, tetracyl peroxydicarbonate, bis (2-ethylhexyl) peroxydicarbonate, azo Diisobutyronitrile, azobisisoheptanonitrile, dibenzoyl peroxide, 1,1-bis(tert-butylperoxy)cyclohexane, 2,2-bis(tert-butylperoxy)butane.

The chain transfer agent of the present invention contains groups that are easy to react with free radicals, including: carbon tetrachloride, carbon tetrabromide, isopropanol, n-butyl mercaptan, specific mercaptan, dodecyl mercaptan, Cetyl mercaptan, octadecyl mercaptan, etc. These chain transfer agents can not only regulate the molecular weight of the polymer, but also have a certain adjustment effect on the viscosity of the polymer after neutralization.

The crosslinking agent molecule of the present invention contains a plurality of vinyl groups, including: trimethylolpropane tri(meth)acrylate, ethylene glycol bis(meth)acrylate, diethylene glycol bis(meth)acrylate ) acrylate, polyethylene glycol bis(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, triallyl isocyanurate, divinylbenzene, three Methylolpropane diallyl ether, pentaerythritol allyl ether, etc. It is mainly used to improve the molecular structure of polymers and adjust molecular weight.

The preparation method of the alkali thickening type rheology modifier that the present invention relates to comprises the following process steps:

A. Synthesis of macromonomers containing carbon-carbon double bonds, long hydrocarbon chains and polyoxyethylene chains

Add 0.1 mole of polyoxyethylene containing hydroxyl and long hydrocarbon chains to a three-necked flask equipped with a stirring device and a distillation device, replace with nitrogen 3 to 6 times, remove oxygen in the system, raise the temperature to 100~110°C, and depressurize Vacuumize for 30 minutes to remove the water in the system, then lower the temperature to 50-70°C. Remove the distillation device, install the reflux condenser and dropping funnel, then add 1 to 3 drops of catalyst and 0.005 to 0.03 grams of polymerization inhibitor, and add 1.0 to 1.1 moles of carbon-containing carbon bis The monomers with bonds and active groups are heated to 80°C, kept for 2 hours for reaction, cooled to room temperature, and discharged to obtain macromonomers.

The polymerization inhibitor can be selected from hydroquinone, p-hydroxyanisole, 2.6-di-tert-butyl p-cresol and the like.

The catalyst is selected from stannous diisooctoate, dibutyltin dilaurate and the like.

B. Synthesis of alkaline thickening rheology modifier

In a 250 ml three-necked flask equipped with a stirring device, a reflux condenser, a dropping funnel, and a nitrogen protection device, 100 ml of organic solvents were added according to the aforementioned weight ratio, and then 4 grams of the macromonomer obtained in step A, containing carbon 16 grams of unsaturated carboxylic acid with carbon double bond, 40 milliliters of remaining organic solvent, 0.1 gram of chain transfer agent, and 0.1 gram of crosslinking agent are mixed and dissolved evenly to make a mixed monomer solution, and then 20 milliliters of mixed monomer solution is added to a three-necked flask , purged with nitrogen for 5 minutes to exclude oxygen, and then began heating to reflux. When the system was refluxed, 0.2 g of initiator was added, and after about 2 to 3 minutes, the polymerization began to exotherm, and the system became turbid at the same time. 5 minutes after the start of the polymerization reaction, add the remaining amount of the mixed monomer solution dropwise from the dropping funnel, continue to reflux for 2 hours after the dropwise addition, then cool and suction filter, and dry the filter cake to obtain a white powder product.

The polymerization reaction temperature in the present invention is 40-110°C, usually more inclined to 50-90°C.

The molecular main chain of the alkali-thickening rheology modifier of the present invention is polymerized by (meth)acrylic acid and the carbon-carbon double bond structure of the macromonomer, and the side chain is composed of an alkyl alcohol polyoxyethylene chain. When the polymer is thickened after being neutralized with alkali in water, due to the electrostatic repulsion of the carboxyl groups on the main chain of the polymer, the main chain of the polymer stretches rapidly in water; at the same time, the hydrophobic chains on its branch chains associate with each other to form Physical crosslinking points that allow polymer solutions to exhibit high viscosity at low shear rates. At higher shear rates, the physical crosslinks formed by hydrophobic associations were destroyed, and the viscosity of the polymer solution showed a tendency to decrease rapidly. Therefore, in the case of very low dosage (less than 1%), the polymer can effectively increase the viscosity of water, polyol and water mixture, and can also improve the shear thinning properties of these solutions.

The advantages of the present invention are:

1. The present invention is formed by polymerization in a normal pressure environment, and the operation is simple and easy.

2. The present invention does not contain expensive fluorine-containing acrylate, so the cost of the polymer is reduced.

3. The polymer with special rheology synthesized by the present invention contains long hydrocarbon hydrophobic chains. In the solution containing the polymer, the viscosity or rheology of the system can be changed at any time by adjusting the pH value of the system.

4. Since the present invention introduces macromonomers containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains, the reaction in the polymerization process is stable, and the product is a loose powder that is easily dispersed in water. After neutralization by adding alkali, it can A rapid increase in viscosity improves the rheology of the solution.

5. The present invention does not add other surfactants as dispersion stabilizers during the polymer synthesis process, so the polymer product will not be polluted by other surfactants. Moreover, the rheology modifier can effectively increase the viscosity of water, polyol or the mixed solution of polyol and water at a low shear rate at a very low concentration, and endow the solution with good shear thinning performance.

Detailed ways

The synthesis of embodiment 1 macromonomer

Add 100 grams of behenyl alcohol polyoxyethylene ether (21) in a 250 ml three-neck flask equipped with a stirring device and a distillation device, replace it with nitrogen 4 times, remove the oxygen in the system, heat up to 100-110 degrees Celsius, reduce Press and evacuate for 30 minutes to get rid of the water in the system, and then lower the temperature to 65 degrees Celsius. Remove the distillation device, install a reflux condenser and a dropping funnel, then add 1 drop of dibutyltin dilaurate and 0.01 g of p-hydroxyanisole, and add 16.7 g of 1,1- Dimethyl-3-isopropenylphenyl methyl isocyanate, after the dropwise addition, the temperature is raised to 80 degrees Celsius, the temperature is lowered after 2 hours of heat preservation reaction, and the material is discharged to obtain the macromonomer.

Embodiment 2 Synthesis of alkali thickening type rheology modifier

Add 100 ml of benzene in a 250 ml three-neck flask equipped with a stirring device, a reflux condenser, a dropping funnel, and a nitrogen protection device, take 4 grams of the macromonomer of Example 1, and 16 grams of acrylic acid, 40 ml of benzene, and 0.1 g Octadecyl mercaptan and 0.1 g of divinylbenzene were mixed and dissolved evenly to make a mixed monomer solution, and 20 ml of the mixed monomer solution was added into a three-necked flask, purged with nitrogen for 5 minutes to exclude oxygen, and then heated to reflux. When the system was refluxing, 0.2 g of dibenzoyl peroxide was added, and after a few minutes, the polymerization started to exotherm, and the system became turbid at the same time. 5 minutes after the start of the polymerization reaction, add the mixed monomer solution dropwise, and the dropwise addition is completed in about 20 to 30 minutes. Continue to keep reflux for 2 hours after the dropwise addition, then cool and suction filter, and dry the filter cake to obtain 19.1 g of white powder.

Example 3 Viscosity of alkali thickening type rheology modifier in aqueous solution

Under stirring, disperse 0.4 grams of the white powder of Example 2 in 320 grams of deionized water, neutralize with triethanolamine at a stirring speed of 300 rpm, and stir well until the thickener forms a hydration in deionized water After gluing, adjust PH=7.5 with triethanolamine to make a solution with a concentration of 0.125%, and then measure the viscosity with the 2# rotor of BROOKFIELLV-DVIII viscometer. The viscosity measured at 25 degrees Celsius is: 6298 centipoise-0.3rpm, 2129 centipoise-3rpm, 665 centipoise-30rpm.

The synthesis of embodiment 4 macromonomer

Add 100 grams of behenyl alcohol polyoxyethylene ether (21) in a 250 ml three-neck flask equipped with a stirring device and a distillation device, replace it with nitrogen 4 times, remove the oxygen in the system, heat up to 100-110 degrees Celsius, reduce Press and evacuate for 30 minutes to get rid of the water in the system, and then lower the temperature to 70 degrees Celsius. Remove the distillation device, install a reflux condenser, and add in a dropping funnel, then add 0.01 g of p-hydroxyanisole, add 9.5 g of methacryloyl chloride dropwise from the dropping funnel under stirring, and heat up to 80 Celsius, heat preservation reaction for 2 hours, then cool down and discharge.

Embodiment 5 Synthesis of alkali thickening type rheology modifier

Add 100 milliliters of benzene in a 250 milliliter three-neck flask equipped with a stirring device, a reflux condenser, a dropping funnel, and a nitrogen protection device, get 4 grams of the macromonomer obtained in Implementation 4, and 16 grams of acrylic acid, 40 milliliters of benzene, 0.1 Mix and dissolve 0.1 g of octadecyl mercaptan and 0.1 g of divinylbenzene to make a mixed monomer solution, add 20 ml of the mixed monomer solution into a three-necked flask, purging with nitrogen for 5 minutes to remove oxygen, and then start heating to reflux . When the system was refluxing, 0.2 g of dibenzoyl peroxide was added, and after a few minutes, the polymerization started to exotherm, and the system became turbid at the same time. 5 minutes after the start of the polymerization reaction, add the mixed monomer solution dropwise, and the dropwise addition is completed in about 20 to 30 minutes. Continue to keep reflux for 2 hours after the dropwise addition, then cool and suction filter, and dry the filter cake to obtain 18.5 grams of white powder.

Embodiment 6 The viscosity of alkali thickening type rheology modifier in aqueous solution

Under stirring, disperse 0.4 g of the white powder of Example 5 in 100 g of deionized water, neutralize with triethanolamine at a stirring speed of 300 rpm, and stir well until the thickener forms a hydration in deionized water After gluing, adjust pH=7.5 with triethanolamine to make a solution with a concentration of 0.4%, and then measure the viscosity with the 3# rotor of BROOKFIELLV-DVIII viscometer. The viscosity measured at 25 degrees Celsius is: 127972 centipoise-0.3rpm, 16196 centipoise-3rpm, 2650 centipoise-30rpm.

Example 7 Viscosity of alkali-thickening rheology modifier in a mixture of ethylene glycol and aqueous solution

Under stirring, disperse 0.2 grams of the above-mentioned white powder in 50 grams of deionized water, then add 50 grams of ethylene glycol and stir evenly. After forming a gel in deionized water, adjust Ph=7.2 with triethanolamine to make a solution with a concentration of 0.2%, and then measure the viscosity with the 2# rotor of a BROOKFIEL LV-DVIII viscometer. Viscosity measured at 25 degrees Celsius: 6998 centipoise - 0.3rpm, 1709 centipoise - 3rpm, 503 centipoise - 30rpm

Embodiment 8 Synthesis of alkali thickening type rheology modifier

Add 30 ml of ethyl acetate and 70 ml of cyclohexane into a 250 ml three-neck flask equipped with a stirring device, a reflux condenser, a dropping funnel, and a nitrogen protection device. Get 4 grams of the macromonomer obtained in Implementation 1, mix and dissolve with 16 grams of acrylic acid, 12 milliliters of ethyl acetate, 28 milliliters of cyclohexane, 0.05 gram of octadecyl mercaptan, and 0.1 gram of divinylbenzene to prepare a mixed monomer solution. 0.1 gram of tetracyl peroxydicarbonate was mixed with 3 milliliters of ethyl acetate and 7 milliliters of cyclohexane to prepare an initiator solution. Add 20 ml of the mixed monomer solution into the three-necked flask, start stirring and purging with nitrogen for 5 minutes to exclude oxygen, and then start heating to 45 degrees Celsius. , add 0.3 g of tetracosyl peroxydicarbonate, after a few minutes, the polymerization starts to exotherm, and the system becomes turbid at the same time. 5 minutes after the start of the polymerization reaction, add the mixed monomer solution dropwise, and use a constant flow pump to add the initiator mixed solution dropwise. The mixed monomer solution will be added dropwise in about 20-30 minutes, and the initiator mixed solution will be added after a delay of 2-3 minutes. . After the dropwise addition was completed, the heat preservation reaction was continued for 2 hours, then cooled and suction filtered, and the filter cake was dried to obtain 17.5 grams of white powder.

Example 9 Viscosity of alkali thickening rheology modifier in aqueous solution

Under stirring, disperse 0.4 g of the white powder of Example 8 in 100 g of deionized water, neutralize with triethanolamine at a stirring speed of 300 rpm, and stir well until the thickener forms a hydration in deionized water After gluing, adjust pH=7.5 with triethanolamine to make a solution with a concentration of 0.4%, and then measure the viscosity with the 3# rotor of BROOKFIELLV-DVIII viscometer. The measured viscosity at 25 degrees Celsius is 81938 centipoise-0.3rpm, 13924 centipoise-3rpm, 2640 centipoise-30rpm.

Embodiment 10 Synthesis of alkali thickening type rheology modifier

Add 30 ml of butyl acetate and 70 ml of decahydronaphthalene into a 250 ml three-necked flask equipped with a stirring device, a reflux condenser, a dropping funnel, and a nitrogen protection device. Get 4 grams of the macromonomer obtained in Implementation 1, mix and dissolve with 16 grams of acrylic acid, 12 milliliters of butyl acetate, 28 milliliters of decahydronaphthalene, 0.05 gram of octadecyl mercaptan, and 0.1 gram of divinylbenzene to prepare a mixed monomer solution. 0.1 gram of 2,2-bis(tert-butylperoxy)butane was mixed with 3 milliliters of butyl acetate and 7 milliliters of decahydronaphthalene to prepare an initiator solution. Add 20 ml of the mixed monomer solution into the three-necked flask, start stirring and purging with nitrogen for 5 minutes to exclude oxygen, and then start heating to 100 degrees Celsius. , add 0.2 g of 2,2-bis(tert-butylperoxy)butane, after a few minutes, the polymerization starts to exotherm, and the system becomes turbid at the same time. 5 minutes after the polymerization reaction starts, add the mixed monomer solution dropwise, and use a constant flow pump to add the initiator mixed solution dropwise. The mixed monomer solution is added dropwise in about 20 to 30 minutes, and the initiator mixed solution is added after a delay of 2 to 3 minutes. . After the dropwise addition was completed, the reaction was continued for 2 hours with heat preservation, then cooled and suction filtered, and the filter cake was dried to obtain 16.5 grams of white powder.

Example 11 Viscosity of alkali thickening rheology modifier in aqueous solution

Under stirring, disperse 0.5 g of the white powder of Example 10 in 100 g of deionized water, neutralize with triethanolamine at a stirring speed of 300 rpm, and stir well until the thickener forms a condensate in deionized water After gluing, adjust pH=7.5 with triethanolamine to make a solution with a concentration of 0.5%, and then measure the viscosity with the 3# rotor of BROOKFIELLV-DVIII viscometer. The viscosity measured at 25 degrees Celsius is: 52846 centipoise-0.3rpm, 8942 centipoise-3rpm, 1782 centipoise-30rpm.

Claims (8)

1. An alkali thickening type rheology modifier is characterized in that it is formed by polymerizing the following components in an organic solvent according to the weight ratio: 50-95 parts of unsaturated carboxylic acid containing carbon-carbon double bond 1-40 parts of macromonomers containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains Initiator 0.1～2 parts Cross-linking agent 0.01～5 parts Chain transfer agent 0.05~4 parts Among them, the organic solvents are: petroleum ether, solvent naphtha, ethyl acetate, butyl acetate, isobutyl acetate, toluene, xylene, benzene, cyclohexane, decahydronaphthalene, n-octane, isooctane or a mixture of these solvents mixture, the amount of the organic solvent is 2 to 20 times the total weight of the component monomers; The molecular structure of macromonomers containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains is A-B-C, and the A, B, and C groups are connected by chemical bonds. The structure of the A group is: R ₁ — R ₁ is a hydrocarbon chain containing 8 to 30 carbons; The structure of the B group is:

m is 1-60; The structure of the C group is: A structure formed by the reaction of unsaturated carboxylic acids containing carbon-carbon double bonds or their anhydrides, acid halides, esters, or isocyanates containing carbon-carbon double bonds with hydroxyl groups at the end of polyoxyethylene. 2. An alkali-thickening rheology modifier as claimed in claim 1, characterized in that it is formed by polymerizing the following components in an organic solvent according to the weight ratio: 60-90 parts of unsaturated carboxylic acid containing carbon-carbon double bond, 5-30 parts of macromonomers containing carbon-carbon double bonds, long carbon-hydrogen chains and polyoxyethylene chains Initiator 0.5～1 part 0.1-2 parts of cross-linking agent 0.1-2 parts of chain transfer agent. 3. An alkali-thickening rheology modifier as claimed in claim 1 or 2, characterized in that the unsaturated carboxylic acid containing carbon-carbon double bonds is composed of one or more than one acrylic acid, methyl Acrylic acid, alpha-cyanoacrylic acid, crotonic acid, butenedioic acid or itaconic acid. 4. An alkali-thickening rheology modifier as claimed in claim 3, characterized in that the unsaturated carboxylic acid containing carbon-carbon double bonds is acrylic acid, methacrylic acid or a mixture of the two in any proportion . 5. An alkali thickening rheology modifier as claimed in claim 1, characterized in that said unsaturated carboxylic acids containing carbon-carbon double bonds or their anhydrides, acid halides, and esters are: (methyl ) acrylic acid, (meth)acryloyl halide, (meth)acrylic anhydride, maleic anhydride, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate or (meth) Isopropyl Acrylate. 6. An alkali-thickening rheology modifier as claimed in claim 1, characterized in that the isocyanate monomer containing carbon-carbon double bonds is: 1, 1-dimethyl-3-isopropenyl Methyl phenyl isocyanate or ethyl 2-isocyanate methacrylate. 7. An alkali thickening rheology modifier as claimed in claim 1 or 2, characterized in that the crosslinking agent is selected from trimethylolpropane tri(meth)acrylate, ethylene glycol bis (meth)acrylate, diethylene glycol bis(meth)acrylate, polyethylene glycol bis(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, tri Allyl isocyanurate, divinylbenzene, trimethylolpropane diallyl ether or pentaerythritol polyallyl ether. 8. An alkali-thickening rheology modifier as claimed in claim 1 or 2, characterized in that the polymerization reaction temperature is 40-110°C.