CN113817131B

CN113817131B - Polyurethane thickener with dispersing function and preparation method and application thereof

Info

Publication number: CN113817131B
Application number: CN202010569418.XA
Authority: CN
Inventors: 冯聪聪; 纪学顺
Original assignee: Wanhua Chemical Group Co Ltd
Current assignee: Wanhua Chemical Group Co Ltd
Priority date: 2020-06-20
Filing date: 2020-06-20
Publication date: 2022-07-12
Anticipated expiration: 2040-06-20
Also published as: CN113817131A

Abstract

The invention discloses a polyurethane type thickening agent with a dispersing function and a preparation method thereof. The polyacrylate-type polyurethane elastomer is obtained by synthesizing polyacrylate polymers and synthesized isocyanate-terminated high-molecular chain segment polymers, and adding polyhydroxy compounds for polymerization reaction. The thickening agent has higher system matching property and compatibility, and higher thickening efficiency, and can reduce the use of a dispersing agent.

Description

Polyurethane thickener with dispersing function and preparation method and application thereof

Technical Field

The invention relates to the field of preparation of high polymer materials, in particular to a polyurethane thickener with a dispersing function, and a preparation method and application thereof.

Background

With the gradual increase of the environmental protection requirements of people and the strict national requirements on environmental protection, the water-based paint system is widely applied at present. The water paint has the advantages of reducing environmental pollution, improving operation and construction environment, saving a large amount of organic solvent, and the like.

The water paint comprises four processes from preparation to film forming, such as manufacturing, storage, construction, leveling and film forming. The viscosity requirements of the coating system vary in different processes, for example during storage of the coating, the need to maintain a high low shear viscosity for long periods of time to prevent the dispersed particles from settling down due to gravity; moderate viscosity is desired in the construction process, so that smooth coating can be ensured, and a certain film forming thickness can be ensured to improve the covering power; the viscosity should be recovered in a short time after construction to facilitate leveling of the coating film, and the viscosity should be rapidly recovered to be high after leveling to prevent sagging. For aqueous coating systems, the viscosity can be adjusted by adjusting the concentration of other solid substances, but the range of adjustment is very limited, and additives are usually added to adjust the viscosity and rheological properties of the system under different shear conditions, and such additives are usually called rheological additives. In addition to providing the desired viscosity of the system, such adjuvants can sometimes improve the flow properties of the system, the dispersion of pigments and fillers in the system, the adhesion of the coating system, and the like.

The traditional thickener for aqueous systems is mainly water-soluble macromolecule, the molecular structure is completely hydrophilic, and the thickener does not contain hydrophobic structures, such as cellulose (HEC) and acrylic thickener (ASE), and the thickener achieves the purpose of thickening the aqueous phase by forming hydrogen bonds with water molecules in the system. The thickening agent can effectively improve the low shear viscosity of a system, but the viscosity is rapidly reduced when the shear is increased, and the defects of easy generation of splashing, insufficient coating, reduction of coating gloss and the like exist in the coating process.

The polyurethane thickener is a thickener developed in the 80 th 20 th century and is a water-soluble oligomer containing hydrophobic groups. The main structure of the thickening agent is a hydrophilic main component, the hydrophilic main component is a hydrophilic polymer chain, and the hydrophilic polymer chain and the hydrophobic group are connected together through covalent bonds to form the associative thickening agent. In aqueous systems, the hydrophilic portion of such thickeners ensures the dissolution or dispersion of the thickener molecules in water by forming hydrogen bonds with water; in an aqueous system, a hydrophobic part on the thickening agent is bridged to emulsion, solid particles and micelles which can form hydrophobic association in the aqueous system to form a spatial three-dimensional network structure, so that the thickening of the aqueous system is realized. Such thickeners can be classified as hydrophobic alkali swellable thickeners (HASE) and polyurethane associative thickeners (HEUR) and other types of associative thickeners. The aqueous system added with HEUR has more excellent leveling property, excellent film fullness and high film-forming gloss, thereby being widely applied.

CN101633718A discloses a comb-shaped polyurethane associative thickener, a preparation method and application thereof. In the patent, a chain extender containing a hydrophobic long chain is synthesized, and the hydrophobic chain segment is increased by introducing the chain extender into a thickener molecule, so that the thickening effect is improved. However, the synthesis process of the chain extender is complicated.

US2009/0124533 and US6020304 describe the use of thickeners obtained by condensation of polyalkylene glycols with isocyanate compounds having hydrophobic chain ends. US2009/012453 describes, among other things, the use of a thickener to which an isocyanate compound and a polyalkylene glycol product are added and which has a saturated, non-ethoxylated C14-C20 alkyl group at the chain end.

WO 2006/002813 describes polyurethane thickeners for various applications in aqueous media. These thickeners are prepared from a hydrophilic polyol having at least two hydroxyl groups, one or more hydrophobic compounds such as long chain alcohols and at least difunctional isocyanates. In this case, an excess of NCO groups is used. The catalyst used was 1, 8-diazabicyclo [5-4-0] undec-7-ene (DABCO).

EP 0725097 describes polyurethane thickeners prepared by reacting polyethers produced by alkoxylation of alcohols or alkylphenols with polyisocyanates under the catalysis of DBTL, diazabicyclooctane or tin dioctoate, where the equivalent ratio of NCO to OH is from 0.9:1 to 1.2: 1. These thickeners have been proposed for use in low shear applications, such as in the flow of water-based latex paints.

EP1765900 describes thickeners for aqueous preparations based on nonionic water-dispersible or water-soluble polyurethanes having a special structure. The special structure of these polymers is achieved by allophanate bonds which are produced by the use of an excess of isocyanate, it being possible to use hydrophilic polyols having at least 2 OH groups, which may additionally contain ether groups.

The polyurethane thickener product described in the above patent can be applied to an aqueous system, but basically can only satisfy the thickening effect, but does not help to disperse the pigment and filler in the whole aqueous system, and does not contribute to the stability of the whole system. The polyurethane thickener with the dispersing function can simultaneously meet the functions of partial dispersion and thickening, has higher thickening efficiency, and ensures that the whole system has better uniformity, the stability of the product and the performance of a paint film, such as water resistance, are more prominent.

Disclosure of Invention

The invention aims to provide a novel polyurethane thickener with a dispersing function and a preparation method thereof aiming at the problems of the existing thickener material. The thickening agent has higher system matching property and compatibility, and higher thickening efficiency, and can reduce the use of a dispersing agent.

The invention optimizes the molecular structure of the polyurethane thickener, introduces the acrylate structure on the molecular main chain of the polyurethane thickener through chain extension and crosslinking, wherein the introduction of the acrylate structure can effectively disperse and adsorb pigments and fillers of a water-based system, increases the anchoring sites of the polyurethane thickener in the whole system, and ensures that the three-dimensional network structure of the whole thickening system is more compact and the matching property and the compatibility of the system are better. Meanwhile, the introduction of the acrylate structure can effectively reduce the use of the dispersing agent, reduce the micromolecule hydrophilic substances of the system and improve the water resistance and the scrubbing resistance of the system. In addition, the ideal viscosity can be obtained by adding a small amount of the product into a formula system.

In order to realize the purpose of the invention, the technical scheme of the invention is as follows:

a polyurethane thickener with a dispersing function, which comprises a polyurethane structure and an acrylate structure on a polymer main chain, and also comprises one or more single-functionality hydrophobic end capping structures on the main chain, wherein the structure of the thickener with the dispersing function is as follows:

wherein the content of the first and second substances,

R₁and R₂Identical or different, being a blocked alkyl radical, preferably said R₁And R₂Containing from 8 to 30 carbon atoms other than the carbon atom of the linking group, more preferably said R₁And R₂Containing from 12 to 26 carbon atoms in addition to the carbon atoms of the linking group,

a is the residue of a polyisocyanate,

b is a residue of a polyether polyol,

d is a residue containing a polyhydroxy compound,

e is an acrylic ester copolymer, and the acrylic ester copolymer,

n is an integer of 1 to 4,

m is any integer of 1 to 2,

y is any integer of 1 to 4,

z is any integer from 1 to 3.

R in the invention₁And R₂Corresponding compounds include, but are not limited to, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, 1-dodecylalcohol, 1-tetradecanol, 1-hexadecanol, 2-butyloctanol, 2-hexyldecanol, octadecanol, the isomeric icosaneAn alcohol. The end-capped hydrophobic structure can effectively control the molecular weight, can form a single end-capped end molecular chain on a main chain to increase, can form an association structure between a coating system and a hydrophobic structure on latex particles or pigments and fillers, participates in the establishment of a three-dimensional network structure of the system, and plays a vital role in improving the viscosity of the whole system.

The polyurethane-type thickener with the dispersing function comprises an acrylate structure on a polymer main chain, wherein the mass average molecular weight (including a carboxylic acid polyethylene glycol ester structure) of the acrylate structure is 2000-30000, preferably 4000-24000, and more preferably 6000-18000. Preferably, it is obtained by reacting monomers comprising:

a)17 wt% to 35 wt% of at least one carboxylic acid monomer including, but not limited to, acrylic acid, methacrylic acid, itaconic acid, fumaric acid, crotonic acid, aconitic acid, or maleic acid, or combinations thereof;

b)50 wt% to 75 wt% of at least one vinyl monomer including, but not limited to, styrene, methyl styrene, vinyl acetate, isobutylene, or combinations thereof;

c)3 wt% -16 wt% of at least one polyethylene glycol carboxylate, wherein the polyethylene glycol carboxylate comprises polyethylene glycol (meth) acrylate, polyethylene glycol itaconate, polyethylene glycol fumarate, polyethylene glycol crotonate, polyethylene glycol aconitate, or polyethylene glycol maleate, or a combination of the polyethylene glycol (meth) acrylate, the polyethylene glycol itaconate, the polyethylene glycol fumarate and the polyethylene glycol crotonate.

The acrylic ester structure of the polyurethane thickener with the dispersion function contains polar carboxylic acid monomers and nonpolar vinyl monomers, and the two monomers can effectively disperse and combine inorganic pigments and organic fillers respectively to ensure the establishment of a stable structure.

The acrylate structure of the polyurethane type thickener with the dispersing function adopts free radical polymerization in the polymerization process, the selected free radical type initiator comprises at least one of organic peroxide compounds, azo compounds, inorganic persulfate compounds and hydrogen peroxide, or optional compositions thereof, and preferably, the selected free radical type initiator comprises but is not limited to azobisisobutyronitrile, azobisisoheptonitrile, benzoyl peroxide, lauroyl peroxide, ammonium persulfate, sodium persulfate and hydrogen peroxide. Benzoyl peroxide is preferred as its free radical initiator in view of its polymerized monomer and product molecular weight herein. The amount of initiator is from 0.01 to 1% by weight, preferably from 0.1 to 0.5% by weight, based on the total amount of monomers.

The polyurethane thickener with the dispersing function, disclosed by the invention, has the advantages that a chain transfer agent is used for effectively controlling the molecular weight of an acrylate structure in the polymerization process, and the chain transfer agent is selected from one or a composition of octyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan, hexadecyl mercaptan, octadecyl mercaptan (ODM), isooctyl 3-mercaptopropionate (IMP), butyl 3-mercaptopropionate, 3-mercaptopropionic acid, butyl thioglycolate, isooctyl thioglycolate and dodecyl thioglycolate; n-dodecyl mercaptan is preferred herein as the chain transfer agent in the present invention. The chain transfer agent is used in an amount of 0.01 to 1% by weight, preferably 0.2 to 0.42% by weight, based on the total amount of monomers.

According to the polyurethane-type thickener with the dispersing function, the hydroxyl number of the polyhydroxy compound related to the polyhydroxy compound residue D is 3-5, and the preferred hydroxyl number is 3; the trihydroxy compound includes but is not limited to glycerol, butanetriol, 1,2, 5-pentanetriol, 1,2, 6-hexanetriol, or a combination of the glycerol, the butanetriol and the glycerol are preferred; the polyhydroxy compound mainly plays a role in crosslinking and chain extension, and can form a bridge between the polyurethane thickener and the acrylate structure.

In the present invention, the polyisocyanate related to the polyisocyanate residue a is a diisocyanate and/or triisocyanate, and preferably the polyisocyanate is an aliphatic diisocyanate.

For example, suitable isocyanates may be 1, 5-naphthalene diisocyanate, 4,4' -diphenylmethane diisocyanate (MDI), Xylylene Diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), 4,4' -diphenyldimethylmethane diisocyanate, 4, 4-bibenzyl diisocyanate, 1, 3-phenylene diisocyanate, 1, 4-phenylene diisocyanate, isomers of Toluene Diisocyanate (TDI), 1-methyl-2, 4-diisocyanatocyclohexane, 1, 6-diisocyanato-2, 2, 4-trimethylhexane, 1-isocyanatomethyl-S-isocyanato-1-trimethylcyclohexane, 4,4' -diisocyanatophenylperfluoroethane, tetramethoxybutane-1, 4-diisocyanate, butane-1, 4-diisocyanate, hexane-1, 6-diisocyanate (HDI), isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate, cyclohexane-1, 4-diisocyanate, ethylene diisocyanate, di-isocyanatoethyl phthalate.

In the invention, the diisocyanate is aliphatic diisocyanate and/or aromatic diisocyanate;

in some embodiments, the aliphatic diisocyanate group of the present invention may be, for example, 1, 4-butylene diisocyanate, 1, 12-dodecamethylene diisocyanate, 1, 10-decamethylene diisocyanate, 2-butyl-2-ethylpentamethylene diisocyanate, 2,4, 4-or 2,2, 4-trimethylhexamethylene diisocyanate, and hexamethylene diisocyanate (hexane-1, 6-diisocyanate, HDI). Also cycloaliphatic diisocyanates are isophorone diisocyanate (IPDI), 2-isocyanatopropylcyclohexyl isocyanate, 4-methylcyclohexane-1, 3-diisocyanate (H-TDI) and 1, 3-bis (isocyanatomethyl) cyclohexane. Furthermore, diisocyanates which are "saturated MDI", such as 4,4 '-methylenebis (cyclohexyl isocyanate) (also known as dicyclohexylmethane-4, 4' -diisocyanate) or 2, 4-methylenebis (cyclohexyl) diisocyanate, can also be present as radicals in the polyurethanes of the invention. The isocyanate plays a role in connection in the polymer, and different units can be grafted to a main chain to generate a common effect, so that the performance requirement of the invention is met.

Preferably, wherein the aliphatic diisocyanate is selected from one or more of 1, 6-Hexamethylene Diisocyanate (HDI), isophorone diisocyanate (IPDI) and dicyclohexylmethane diisocyanate (HMDI);

preferably, wherein the aromatic diisocyanate is selected from Toluene Diisocyanate (TDI) and/or 4, 4-diphenylmethane diisocyanate (MDI).

In the invention, the triisocyanate is one or more of 4,4' triphenylmethane triisocyanate, 2-isocyanatoethyl 2, 6-diisocyanatohexanoate and HDI tripolymer.

In the present invention, the polyether polyol related to the polyether polyol residue B is one or more of polyethylene glycol (PEG), polypropylene glycol (PPG), polyethylene glycol-polypropylene glycol (PEG-PPG) and polytetramethylene glycol, and preferably polyethylene glycol (PEG).

In the present invention, the molecular weight of the polyether polyol is 2000-20000 dalton, preferably 4000-8000 dalton.

Another object of the present invention is to provide a method for preparing the polyurethane-based thickener having a dispersing function.

In the invention, the preparation method of the polyurethane type thickener with the dispersing function comprises the following steps:

a) adding carboxylic acid polyethylene glycol ester, carboxylic acid monomers and vinyl monomers into a solvent at 85-90 ℃ in a nitrogen environment, carrying out free radical polymerization, and obtaining a polyacrylate polymer after the reaction is completed;

b) carrying out polymerization reaction on polyether polyol, end-capped alkyl and polyisocyanate in the presence of a catalyst, preferably dehydrating the polyether polyol at the temperature of 100-120 ℃, cooling to 75-85 ℃, adding the end-capped alkyl into the polyether polyol, and uniformly mixing; under the nitrogen environment, adding a catalyst and polyisocyanate into the mixture, starting a polymerization reaction, and reacting for a certain time to obtain an isocyanate-terminated high-molecular chain polymer;

c) adding the monoacrylate polymer synthesized in the step a) into the isocyanate-terminated polymer chain segment polymer synthesized in the step b), adding a polyhydroxy compound, uniformly mixing, keeping the mixture in a nitrogen environment, heating to 75-85 ℃ to start a polymerization reaction, and obtaining the polyurethane thickener with the dispersing function after the reaction is complete.

The polyacrylate polymer synthesized in the step a) of the invention is free radical polymerization by a solvent method, the selection standard of the solvent is that no active hydrogen group capable of reacting with isocyanate group exists, and the solvent has a proper melting point and a proper boiling point, and the solvent comprises but is not limited to benzene, toluene, xylene, ethylbenzene, chloroform, acetone, butyl acetate or a plurality of combinations thereof; in view of environmental requirements, butyl acetate is preferred here in an amount of 58 to 60%, based on the polyacrylate polymer.

In the method, the using amount of the carboxylic acid polyethylene glycol ester in the step (a) is 3 to 16 weight percent, the using amount of the carboxylic acid monomer is 17 to 35 weight percent, and the using amount of the vinyl monomer is 50 to 75 weight percent; based on the total mass of the polyacrylate polymer.

In the process of the present invention, the polyether polyol in step (b) is used in an amount of 90 to 95.5% by weight, the blocked alkyl group is used in an amount of 0.7 to 1.6% by weight, and the polyisocyanate is used in an amount of 3.5 to 9% by weight, based on the total amount of the isocyanate group-blocked polymer segment.

In the process of the present invention, the amount of the polyacrylate polymer used in step (c) is from 20% by weight to 444.5% by weight, the amount of the synthetic isocyanate group-terminated polymer segment used is from 55.2% by weight to 77.6% by weight, and the amount of the polyol used is from 0.2% by weight to 0.4% by weight, based on the total amount of the resin copolymer (polyurethane-type thickener).

The isocyanate group-terminated polymer segment synthesized in step b) of the present invention can be prepared by various methods for preparing polyurethane resin, and the synthesis can be carried out in the absence of water, for example, azeotropic dehydration or vacuum heating dehydration can be used in some embodiments; during reaction, nitrogen is adopted for protection to prevent water vapor from entering. The synthesis can be carried out by a solution method or a bulk synthesis method. The invention preferably adopts a bulk method for synthesis.

In some embodiments, the reaction temperature in step a), step b) and step c) of the present invention is not strictly limited, and may be selected from 40 to 130 ℃, preferably from 50 to 120 ℃, and more preferably from 70 to 110 ℃, and the optimal reaction temperature may be selected to effectively reduce the formation of by-products and improve the quality of the product.

In some embodiments, the reaction times for step a), step b) and step c) of the present invention are 0.5 to 4 hours, 1 to 4 hours, and 3 to 8 hours, respectively.

In some embodiments, step a), step b) and step c) of the present invention require protection with an inert gas, which is nitrogen and/or helium, preferably nitrogen.

In addition, the preparation steps b) and c) of the polyurethane-type thickener with a dispersing function according to the present invention are carried out under the condition of a catalyst, wherein the catalyst is one or more of an organic metal catalyst and/or an amine catalyst. Wherein the organic metal catalyst is one or more of dibutyltin dilaurate, stannous octoate, bismuth decanoate, bismuth octoate and silver catalysts; the amine catalyst is triethylamine and/or 1, 4-diazabicyclo [2.2.2] octane. b) The dosage of the medium catalyst is 0.005-0.2 wt% of the total dosage of the polyisocyanate and the polyether polyol; c) the dosage of the medium catalyst is 0.001-0.1 wt% of the total amount of the polyacrylate polymer and the isocyanate group-terminated polymer chain segment polymer.

Still another object of the present invention is to provide a use of the polyurethane-type thickener having a dispersing function.

The application of the polyurethane thickening agent with the dispersing function is characterized in that the polyurethane thickening agent with the dispersing function is applied to the fields of building coatings, water-based industrial paints, textile synthetic leather and the like.

The invention has the positive effects that:

the polyurethane thickener with the dispersing function introduces an acrylate structure on the molecular main chain of the polyurethane thickener through chain extension and crosslinking, wherein the introduction of the acrylate structure can effectively generate an adsorption effect on pigment fillers (titanium dioxide, heavy calcium, kaolin and other pigment fillers) of a water-based system and control and disperse the pigment fillers, so that the anchoring sites of the polyurethane thickener in the whole system are increased. Meanwhile, the polyurethane thickener with the dispersing function has higher thickening efficiency in an aqueous system, can effectively reduce the use of a dispersing agent, reduce micromolecule hydrophilic substances of the system, and improve the water resistance and the scrubbing resistance of the system.

Description of the drawings:FIG. 1 is a GPC chart of the polyacrylate polymer prepared in example 1.

Detailed Description

In order to better practice the invention, the following examples are given for further illustration, but the examples are not intended to limit the invention.

GPC measurement Instrument model e2695-2414RID, Vott.

The products polyurethane thickener B1 and polyurethane thickener B2 were selected for comparison on the market and compared with the products made in the following examples in different coating formulations.

Wherein the selected polyurethane thickener B1 is of DOW chemistry

RM-8W and B1 are traditional straight-chain thickeners which are mainly polymerized by polyethylene glycol, polyisocyanate and blocked alkyl chain. The product has high market acceptance, and the main parameters are as follows:

appearance of the product	Turbid liquid
		Chemical type	Nonionic polyurethanes
Density of	1.044g/cm³
		Viscosity of the solution	3000cp
Non-volatile substance	21.5％
		Solvent(s)	Water (W)

Wherein the selected polyurethane thickener B2 is Coatex chemical

830W, B2 is a traditional comb-type thickener, which is mainly polymerized by polyethylene glycol, polyisocyanate and blocked alkyl chain. The product has high market acceptance, and the main parameters are as follows:

appearance of the product	White viscous liquid (20 ℃ C.)
		Chemical type	Nonionic aqueous polyurethanes
Density of	1.06g/cm³
		Viscosity of the solution	6000cp
Non-volatile matter	30％
		pH value	6.5±1

The main monomer information is as follows:

example 1

The polyurethane thickener C1 with a dispersing function is prepared, and the synthesis formula comprises the following components:

TABLE 1

The polyurethane thickener with the dispersing function, which is synthesized by adopting the formula, comprises the following steps:

1) under nitrogen atmosphere, adding 53.4g of butyl acetate into a 500ml flask, starting stirring and heating to 90 ℃, weighing 20g of butyl acetate, 1.8g of acrylic acid polyethylene glycol-11, 11.78g of acrylic acid, 35.35g of styrene, 0.098g of BPO and 0.15g of dodecyl mercaptan in a dropping bottle, uniformly mixing, dropping liquid in the dropping bottle into the flask for polymerization within 2 hours, keeping the temperature for 2 hours after dropping, cooling to normal temperature for later use, and testing the polyacrylate polymer (the mass average molecular weight of which is 14677 through GPC test) obtained by the reaction, wherein the GPC spectrogram of the polyacrylate polymer is shown in figure 1;

2) adding 100g polyethylene glycol 6000(PEG6000) into 500ml three-neck flask equipped with electromagnetic stirring and nitrogen inlet, and removing water at negative pressure (pressure less than 100Pa) at 110 deg.C for 2 hr;

3) cooling to 80 ℃, introducing nitrogen into the three-neck flask to relieve pressure, adding 0.788g of tetracosanol into the three-neck flask, and mechanically stirring until the mixture is uniformly stirred;

4) under the protection of nitrogen, 0.2g of 8108R and 4.11g of HDI are added into a three-neck flask to start polymerization reaction for 2 hours, and after the full reaction is completed, the temperature is reduced to 60-65 ℃ for standby application, so as to obtain the isocyanate-terminated high-molecular chain polymer;

5) adding the polyacrylate polymer obtained by the reaction in the step 1) into the isocyanate-terminated high-molecular chain segment polymer obtained by the reaction in the step 4), adding 0.31g of glycerol and 0.1g of 8108R catalyst, starting to stir and mix uniformly, heating to 85 ℃, reacting for 5 hours to ensure that the reaction is complete, and cooling to 65 ℃ for later use to obtain the polyurethane thickener resin with the dispersing function.

6) 286.3g of deionized water with the temperature of 65 ℃ is added into the polymer obtained by the reaction of 5) for dispersion for 2.5 hours, and the temperature is reduced to the normal temperature, so that the polyurethane thickener C1 with the dispersion function is obtained.

Wherein n is 1, m is 1, y is 4, and z is 3.

Example 2

The polyurethane thickener C2 with the dispersing function is prepared, and the synthesis formula comprises the following components:

TABLE 2

The procedure of example 2 was the same as in example 1 and no further details were given here, giving a polyacrylate polymer having a mass average molecular weight of 17762 by GPC measurement, giving a polyurethane thickener C2 with dispersing function according to this formulation,

wherein n is 4, m is 1, y is 1, and z is 2.

Example 3

The polyurethane thickener C3 with the dispersing function is prepared, and the synthesis formula comprises the following components:

TABLE 3

The procedure of example 3 was the same as in example 1 and no further details were given here, giving a polyacrylate polymer having a mass average molecular weight of 15478 by GPC measurement, giving a polyurethane thickener C3 having a dispersing function according to this formulation,

wherein n is 2, m is 2, y is 3, and z is 1.

Example 4

The polyurethane thickener C4 with the dispersing function is prepared, and the synthesis formula comprises the following components:

TABLE 4

The procedure of example 4 was the same as in example 1 and no further details were given here, giving a polyacrylate polymer having a mass average molecular weight of 14967 by GPC measurement, giving a polyurethane thickener C4 with dispersing function according to this formulation,

wherein n is 1, m is 1, y is 2, and z is 2.

Example 5

The polyurethane thickener C5 with the dispersing function is prepared, and the synthesis formula comprises the following components:

TABLE 5

The procedure of example 5 was the same as in example 1 and no further details were given here, giving a polyacrylate polymer having a mass average molecular weight of 16359 by GPC measurement, giving a polyurethane thickener C5 having a dispersing function according to this formulation,

wherein n is 2, m is 1, y is 2, and z is 2.

The following examples 6 to 8 are comparative examples using the above thickener having a dispersing function and commercially available thickeners B1 and B2. The items and methods to be tested are as follows:

1) adding the same amount of thickener into the system, and inspecting the KU viscosity of the system;

2) gloss testing: carrying out three parallel tests at an angle of 60 degrees by using a gloss meter, and taking an average value;

4) the storage stability is that the prepared finished paint is put into a 50 ℃ oven and is placed for 14 days, and the performance of the finished paint is inspected; and (3) judging standard: the storage stability was good at 5 points, not good at 1 point;

5) and (3) testing the activation period: mixing the component A and the component B at the room temperature of 25 ℃ and the humidity of 50 percent, adding water to dilute the mixture to the construction viscosity, and tracking the viscosity change of the mixture.

6) And (3) weather resistance test: keeping the temperature in an UVB-313nm aging box at 60 ℃, illuminating for 4 hours by adopting the light intensity of 0.68w/m2, taking out a paint film and then condensing for 4 hours at 50 ℃; alternately circulating the two solutions until 1000 hours, and inspecting the performance of the paint film; and (3) judging standard: the weather resistance is good by 5 minutes, and the weather resistance is bad by 1 minute;

7) and (3) testing water resistance: preparing a film with the thickness of 20 microns on a polished tinplate with the humidity of 50% at the room temperature of 25 ℃, putting the tinplate containing a paint film into water for 7 days, and observing the foaming condition of the foamed paint film; and (4) judging standard: the water resistance is good for 5 minutes, and the water resistance is poor for 1 minute;

8) and (3) baking varnish drying process: film preparation, namely drying the surface of a paint film for 20 minutes at room temperature, then putting the paint film into an oven at 80 ℃ for baking for 5 to 10 minutes, then heating to 140 ℃ for baking for 30 minutes, and finishing drying;

9) two-component drying process: preparing a film, drying the surface of the paint film for 20 minutes at room temperature, baking the paint film in an oven at 80 ℃ for 30 minutes, and curing the paint film for 24 hours at room temperature to test the performance;

10) scrub resistance test: manufacturing a plate according to the national standard GB/T9266-aid 2009, and testing by adopting a BGD 526 architectural coating scrub-resistant instrument;

11) and (3) testing the contrast ratio: manufacturing a board according to the national standard GB/T23981-2009, and testing by adopting a C84-III reflectivity instrument;

12) thin fly viscosity: the viscosity (25 + -1 ℃) at 750rpm was measured using a thin-fledged viscometer model CA2000 +;

13) and (3) testing the anti-adhesion property: coating a film on the cloth, baking the cloth in an oven at 160 ℃ for 1 minute, taking the cloth out at room temperature (25 +/-1 ℃) overnight, and measuring and sensing the hand-sticking effect by hands the next day, wherein the hand-sticking effect is 5 minutes and the hand-sticking effect is 1 minute;

14) and (3) testing the slip property: coating a film on the cloth, putting the cloth into a 160 ℃ oven to bake for 1 minute, taking the cloth out at room temperature (25 +/-1 ℃) for one night, and measuring and sensing the smooth effect of the cloth by hands the next day, wherein the smooth effect is 5 minutes, and the rough effect is 1 minute;

15) flexibility test: coating a film on the cloth, putting the cloth into a 160 ℃ oven to bake for 1 minute, taking the cloth out at room temperature (25 +/-1 ℃) overnight, and measuring and sensing the soft effect of the cloth by hands the next day, wherein the soft effect is 5 minutes and the hard effect is 1 minute;

16) and (3) testing washing fastness: coating a film on the cloth, baking the cloth in an oven at 160 ℃ for 1 minute, taking the cloth out at room temperature (25 +/-1 ℃) overnight, washing the cloth with a washing machine the next day, observing the coating effect after the washing is finished, wherein the retention is more, preferably 5 minutes, and the retention is less, preferably 1 minute.

In the application examples, the raw materials and manufacturer specifications used are as follows:

example 6

The building coating is a branch of the largest amount of the water-based coating market, the maturity is high, and the application types of the thickening agent are more. This application example shows the application of the polyurethane thickeners C1, C2, C3, C4 and C5 with dispersing function synthesized in examples 1 to 5 of the present invention in building coating and comparison with commercial products.

Building interior wall formula: 44% PVC

TABLE 6

Description of the drawings: the self-made C1-C5 has less dispersant for dispersing the functional thickener.

In this formulation, comparative examples synthesized polyurethane thickeners C1-C5 with dispersing function and commercially available products B1, B2, the following Table results were obtained:

TABLE 7

Test items	B1	B2	C1	C2	C3	C4	C5
								KU viscosity	101	103	106	109	110	112	116
Scrub resistance	4	3	5	5	5	5	5
								Water resistance	3	4	5	5	5	5	5
Storage stability	3	4	4	5	5	5	5
								Contrast ratio	0.95	0.94	0.95	0.96	0.96	0.96	0.97

As can be seen from Table 7, the polyurethane thickener with dispersing function of this invention has good thickening efficiency in PVC 44% building interior wall formulation without adversely affecting scrub resistance, water resistance, storage stability and contrast ratio.

Example 7

In a water-based two-component system, the paint has the performance similar to that of an oil-based paint and is environment-friendly, so the paint is developed quickly in recent years and is also an important application direction of water-based paint industrial paint. This application example demonstrates the use of the polyurethane thickeners with dispersing function of the present invention in a two-component system and comparison with commercially available products. Before construction, the formula needs to be mixed with A and B, 10-15% of water is added for boiling and diluting to the construction viscosity.

The formula of the two components is as follows:

TABLE 8

Description of the elements: the self-made C1-C5 has less dispersant for the thickener with the dispersing function.

In this formulation, comparative examples were synthesized with polyurethane thickeners C1-C5 and with commercial products B1, B2 having the following table results:

TABLE 9

Test items	B1	B2	C1	C2	C3	C4	C5
								KU viscosity	77	79	85	83	87	88	92
Gloss of	79	81	83	84	83	83	85
								Water resistance	4	4	5	5	5	5	5
Storage stability	3	4	4	4	4	5	5
								Period of activation	>4h	>4h	>4h	>4h	>4h	>4h	>4h
Weather resistance	5	5	5	5	5	5	5

As can be seen from Table 9, the polyurethane thickeners having dispersing function of the invention have good thickening efficiency in the dispersion baking varnish without adversely affecting gloss, transparency, storage stability and high temperature stability.

Example 8

In recent years, the textile printing direction puts more strict requirements on environmental protection, so that the water-based textile printing coating is rapidly developed. This application example shows the comparison of the use of the polyurethane thickeners with dispersing function according to the invention with the commercial products B1, B2 in the textile printing direction.

Watch 10

TABLE 11

As can be seen from Table 11, the polyurethane thickener having a dispersing function of the present invention has a good thickening efficiency in this textile printing coating and is excellent in releasing property, slipping property, storage stability, softness and washing fastness.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, simplifications, substitutions and equivalents which do not depart from the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A polyurethane thickener with a dispersing function is characterized in that a polymer main chain of the thickener comprises a polyurethane structure and an acrylate structure at the same time, and the main chain also comprises one or more monofunctional hydrophobic end-capping structures, wherein the thickener with the dispersing function has the following structure:

wherein the content of the first and second substances,

R₁and R₂Identical or different, are end-capped alkyl groups,

a is the residue of a polyisocyanate,

b is a residue of a polyether polyol,

d is a residue containing polyhydroxy compound, the polyhydroxy compound is one or more of glycerol, butanetriol, 1,2, 5-pentanetriol and 1,2, 6-hexanetriol,

e is an acrylic ester copolymer, and the acrylic ester copolymer,

n is an integer of 1 to 4,

m is any integer of 1 to 2,

y is any integer of 1 to 4,

z is any integer from 1 to 3.

2. The polyurethane-type thickener having a dispersing function as claimed in claim 1, wherein R is₁And R₂Containing from 8 to 30 carbon atoms in addition to the carbon atoms of the linking group.

3. The polyurethane-type thickener having a dispersing function as claimed in claim 1, wherein R is₁And R₂Containing from 12 to 26 carbon atoms in addition to the carbon atoms of the linking group.

4. The polyurethane-type thickener having a dispersing function as claimed in claim 1, wherein the mass average molecular weight of the acrylate structure contained in the polymer main chain is 2000-30000, which is obtained by reacting monomers comprising:

a) at least one carboxylic acid monomer

b) At least one vinyl monomer

c) At least one carboxylic acid polyethylene glycol ester.

5. The polyurethane-based thickener having a dispersing function as claimed in claim 4, wherein the mass average molecular weight of the acrylate structure contained in the polymer backbone is 4000-24000, and the carboxylic acid monomer is selected from acrylic acid, methacrylic acid, itaconic acid, fumaric acid, crotonic acid, aconitic acid, or maleic acid, or a combination thereof; the vinyl monomer is selected from styrene, methyl styrene, vinyl acetate, isobutene or a combination of a plurality of the styrene, the methyl styrene, the vinyl acetate and the isobutene; the carboxylic acid polyethylene glycol ester is selected from polyethylene glycol (methyl) acrylate, polyethylene glycol itaconate, polyethylene glycol fumarate, polyethylene glycol crotonate, polyethylene glycol aconitate, or polyethylene glycol maleate, or a combination of the polyethylene glycol esters.

6. The polyurethane-type thickener having a dispersing function as claimed in claim 5, wherein the mass average molecular weight of the acrylate structure contained in the polymer main chain is 6000-.

7. The polyurethane-type thickener having a dispersing function as claimed in claim 4, wherein the amount of said monomer is: a)17 to 35 wt% of at least one carboxylic acid monomer,

b) 50-75 wt% of at least one vinyl monomer

c)3 to 16 weight percent of at least one carboxylic acid polyethylene glycol ester.

8. The polyurethane-type thickener having a dispersing function as claimed in any of claims 1 to 7, wherein the compound corresponding to the terminal alkyl group is selected from the group consisting of dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, 1-dodecylalcohol, 1-tetradecanol, 1-hexadecanol, tetracosanol, hexacosanol, 2-butyloctanol, 2-hexyldecanol, octadecanol and the isomeric eicosanol.

9. The polyurethane-type thickener having a dispersing function as claimed in any of claims 1 to 7, wherein the polyisocyanate to which the polyisocyanate residue A relates is a diisocyanate and/or triisocyanate,

and/or the diisocyanate is aliphatic diisocyanate and/or aromatic diisocyanate;

and/or the triisocyanate is one or more of 4,4' triphenylmethane triisocyanate, 2-isocyanatoethyl 2, 6-diisocyanatohexanoate, and HDI trimer.

10. The polyurethane-based thickener having a dispersing function as claimed in claim 9, wherein the polyisocyanate is an aliphatic diisocyanate.

11. The polyurethane-type thickener having a dispersing function as claimed in claim 10, wherein the aliphatic diisocyanate is one or more selected from the group consisting of 1, 6-hexamethylene diisocyanate, isophorone diisocyanate and dicyclohexylmethane diisocyanate; the aromatic diisocyanate is selected from toluene diisocyanate and/or 4, 4-diphenylmethane diisocyanate.

12. The polyurethane-based thickener having a dispersing function as claimed in any one of claims 1 to 7, wherein the polyether polyol to which the polyether polyol residue B relates is one or more of polyethylene glycol, polypropylene glycol, polyethylene-polypropylene glycol and polybutylene glycol;

and/or the polyether polyol has a molecular weight of 2000-.

13. The polyurethane-type thickener having a dispersing function as claimed in claim 12, wherein the polyether polyol to which the polyether polyol residue B relates is polyethylene glycol; and/or the polyether polyol has a molecular weight of 4000-.

14. A method for preparing the polyurethane-type thickener having a dispersing function according to any one of claims 1 to 7, comprising the steps of:

a) adding carboxylic acid polyethylene glycol ester, a carboxylic acid monomer and a vinyl monomer into a solvent, and carrying out free radical polymerization to obtain a polyacrylate polymer;

b) carrying out polymerization reaction on polyether polyol, end-capped alkyl and polyisocyanate in the presence of a catalyst, adding the end-capped alkyl into the polyether polyol, and uniformly mixing; under the nitrogen environment, adding a catalyst and polyisocyanate into the mixture to carry out polymerization reaction to obtain an isocyanate group-terminated high-molecular chain segment polymer;

c) adding the polyacrylate polymer synthesized in the step a) into the isocyanate-terminated high-molecular chain segment polymer synthesized in the step b), adding a polyhydroxy compound, uniformly mixing, and carrying out polymerization reaction under a nitrogen environment to obtain the polyurethane-type thickening agent with the dispersing function.

15. The method according to claim 14, wherein the polyether polyol is subjected to dehydration treatment in step b).

16. The method according to claim 14, wherein the amount of the carboxylic acid polyglycol ester in the step (a) is 3 wt% to 16 wt%, the amount of the carboxylic acid monomer is 17 wt% to 35 wt%, and the amount of the vinyl monomer is 50 wt% to 75 wt%, based on the total mass of the polyacrylate polymer; and/or the solvent is a solvent without active H, and comprises one or more of benzene, toluene, xylene, ethylbenzene, chloroform, acetone and butyl acetate.

17. The method of claim 16, wherein the solvent is butyl acetate.

18. The method of claim 14, wherein the polyether polyol in step (b) is used in an amount of 90 wt% to 95.5 wt%, the blocked alkyl group is used in an amount of 0.7 wt% to 1.6 wt%, and the polyisocyanate is used in an amount of 3.5 wt% to 9 wt%, based on the isocyanate-terminated polymer segment.

19. The method of claim 14, wherein the polyacrylate polymer is used in the amount of 22 wt% to 44.5 wt%, the synthetic isocyanate-terminated polymer having a high molecular chain segment is used in the amount of 55.2 wt% to 77.6 wt%, and the polyol is used in the amount of 0.2 wt% to 0.4 wt%, based on the total amount of the resin copolymer in step (c).

20. Use of the polyurethane-based thickener having a dispersing function according to any one of claims 1 to 13 or the polyurethane-based thickener having a dispersing function prepared by the preparation method according to any one of claims 14 to 19 in the fields of architectural coatings, aqueous industrial paints, textile synthetic leather.