Hyperbranched polyurethane associated rheology modifier as well as preparation method and application thereof

Abstract

The invention provides a hyperbranched polyurethane associated rheology modifier as well as a preparation method and application thereof, and belongs to the technical field of coating assistants. Firstly, polyethylene glycol 6000 is used as a soft chain segment, excessive isophorone diisocyanate is used as a hard chain segment, 1, 4-butanediol is used as a hydrophilic micromolecule chain extender, triethanolamine is used as a chain extender, and a hyperbranched polyurethane associated rheology modifier is prepared; reacting under the catalytic action of dibutyltin dilaurate to generate an isocyanate-terminated prepolymer with a hydrophilic chain segment; then, carrying out branched chain extension by adopting second-generation hyperbranched polyol as a branched core, so as to obtain a hyperbranched intermediate; finally, the branched poly (1, 4-butanediol adipate) and pentaerythritol triacrylate are used as hydrophobic chain segments for end capping, and the hyperbranched polyurethane associated rheological modifier with excellent thickening capacity and rheological property is prepared.

Description

Technical Field

[0001] The invention belongs to the technical field of coating additives and relates to a hyperbranched polyurethane associative rheology modifier, a preparation method and application thereof. Background Art

[0002] Rheology modifiers are key functional additives for regulating the viscoelastic behavior of fluids. They change the rheological properties of the system through intermolecular forces or specific structural designs, and are widely used in polymer processing, oilfield chemistry, pharmaceutical carriers and other fields. Traditional rheology adjustment systems mostly rely on cellulose derivatives, acrylic acid or inorganic thixotropic agents, but these materials have significant defects: cellulose has poor electrolyte resistance and is easily degraded by microorganisms; acrylic acid is sensitive to pH and is prone to decomposition at high temperatures; inorganic thixotropic agents require high addition amounts and are prone to reduce the transparency of the system. The above defects seriously restrict its application stability under complex working conditions.

[0003] In recent years, polyurethane associative rheology modifiers have attracted attention due to their environmental friendliness and designability. Its molecular chain is usually composed of hydrophilic-hydrophobic blocks, and a dynamic physical cross-linked network is formed through the association of terminal hydrophobic groups to achieve shear-responsive viscosity regulation. However, traditional linear polyurethane thickeners have two major bottlenecks: first, the molecular chain ends contain only two hydrophobic end groups, and the association site is single, resulting in a sparse network structure and easy dissociation at high temperatures; second, when the proportion of rigid segments is too high, the flexibility of the molecular chain decreases, and it is difficult to quickly reconstruct the network at low shear rates, resulting in insufficient thixotropy. Existing technologies attempt to introduce branched structures to increase the density of association sites, but conventional methods (such as star branching) often lead to uneven distribution of functional groups due to uncontrollable branching degree, and the uniform length of the branch chain limits the formation of multi-scale networks.

[0004] Some studies use hyperbranched polyols as branching cores, but do not solve the problem of coordinated design of terminal hydrophobic groups and main chains. Therefore, developing a rheology modifier with high branching controllability, multi-dimensional association sites and dynamic responsiveness has become the key to breaking through the existing technical barriers. It is urgent to achieve precise rheological control in a wide shear range while ensuring system stability through molecular structure innovation. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention aims to provide a hyperbranched polyurethane associative rheology modifier, a preparation method and application thereof. The present invention uses polyethylene glycol 6000 as a soft segment, an excess of isophorone diisocyanate as a hard segment, 1,4-butanediol as a hydrophilic small molecule chain extender, and triethanolamine as a chain extender, and reacts under the catalytic action of dibutyltin dilaurate to generate an isocyanate-terminated prepolymer with a hydrophilic segment, and then uses a second-generation hyperbranched polyol as a branching core for branching chain extension to obtain a hyperbranched intermediate; finally, branched polyadipate-1,4-butanediol ester and pentaerythritol triacrylate are used as hydrophobic segments for end-capping to prepare a hyperbranched polyurethane associative rheology modifier with excellent thickening ability and rheological properties.

[0006] To achieve this object, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a method for preparing a hyperbranched polyurethane associative rheology modifier, the preparation method comprising: Step (I), adding polyethylene glycol 6000 into a reaction kettle, dehydrating the polyethylene glycol 6000, adding isophorone diisocyanate to the dehydrated polyethylene glycol 6000 in a nitrogen atmosphere, mixing, stirring and heating to obtain a reaction solution; adding 1,4-butanediol to the reaction solution, mixing, stirring and heating to obtain a first precursor solution; adding triethanolamine to the first precursor solution, mixing, stirring and heating to obtain a second precursor solution; adding dibutyltin dilaurate to the second precursor solution, mixing, stirring and heating to obtain a prepolymer terminated by an isocyanate group; Step (II), under a nitrogen atmosphere, trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed and heated to react to obtain a polyol intermediate; the polyol intermediate, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed and heated to react to obtain a hyperbranched polyol; the hyperbranched polyol, 1,4-butanediol and acetone are added to the prepolymer obtained in step (I), the mixture is stirred and heated to cause a branching reaction, and a hyperbranched intermediate is obtained after the reaction is completed; Step (III), adding branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol to the hyperbranched intermediate obtained in step (II), stirring and heating to cause a capping reaction, obtaining an intermediate product after the reaction is completed, cooling the intermediate product, and then adding a neutralizer solution to the intermediate product under high-speed stirring conditions for emulsification to obtain the hyperbranched polyurethane associative rheology modifier.

[0007] The invention uses polyethylene glycol 6000 as a soft segment, an excess of isophorone diisocyanate as a hard segment, and 1,4-butanediol as a hydrophilic small molecule chain extender, and reacts under the catalytic action of dibutyltin dilaurate to generate an isocyanate-terminated prepolymer with a hydrophilic segment, wherein the introduction of 1,4-butanediol can increase the proportion of hydrophilic functional groups in the hydrophilic segment, which is beneficial to improving the dispersibility of the rheology modifier in the aqueous emulsion; subsequently, the invention uses a second-generation hyperbranched polyol as a branched core, and the hyperbranched structure in the prepared hyperbranched polyol is controllable, and the number of hyperbranching iterations can be adjusted according to different ratios of raw materials, so as to provide more reaction functional groups for subsequent end-capping reactions, and utilize a large number of hydroxyl groups on the hyperbranched polyol to form a controllable hyperbranched structure. The reaction characteristics of the isocyanate group at the end of the prepolymer molecular chain are used to branch and extend the chain to obtain a hyperbranched intermediate. The introduction of hyperbranched polyols makes the branch structure more complicated. Finally, branched poly(1,4-butylene adipate) and pentaerythritol triacrylate are used as hydrophobic segments, and the hydroxyl groups at the ends of the branched poly(1,4-butylene adipate) and pentaerythritol triacrylate molecular chains are used to block the ends with the isocyanate groups at the ends of the hyperbranched intermediates to prepare a hyperbranched polyurethane associative rheology modifier. Due to the hydrophobic association between the hydrophobic segments of the rheology modifier, the macromolecular chains can form a more complete spatial network structure through cross-linking, which greatly improves the thickening ability and rheological properties of the rheology modifier for the aqueous emulsion system.

[0008] Compared with the straight-chain rheology modifier with hydrophobic functional group structures at both ends, the molecular side chain of the rheology modifier synthesized by the present invention carries more hydrophobic functional groups, and the two-point association is changed to multi-point association. Compared with the two-point association, the multi-point association can form a more dense and stable association network. The rheological test shows that the viscosity of the aqueous emulsion without the rheology modifier prepared by the present invention is very low. With the increase of shear rate, the viscosity of the aqueous emulsion changes little, and no obvious shear thinning phenomenon occurs; when the rheology modifier prepared by the present invention is added to the aqueous emulsion, the viscosity of the entire emulsion system increases rapidly, and the viscosity of the system decreases significantly with the increase of shear rate, showing obvious thixotropy.

[0009] The present invention adopts a process route of first branching and chain extension followed by hydrophobic end-capping to prepare a rheology modifier with a hyperbranched structure. If a process route of first hydrophobic end-capping and then branching and chain extension is adopted, a star-shaped structure is obtained. Compared with the star-shaped structure, the hyperbranched structure rheology modifier prepared by the present invention has better thickening ability and thixotropic properties. This is because the hydrophilic segments of the rheology modifier and the water in the emulsion system undergo hydrogen bond coupling, which slows down the fluidity of the water. The presence of the hydrophilic segments provides a guarantee for the viscosity stability and chemical stability of the rheology modifier, and the hydrophobic segments at the ends of the polymer form micelles or are adsorbed on different micelle particles or latex particles in the emulsion system, so that the rheology modifier molecules form bridges between the particles. Due to the rheology modifier of the hyperbranched structure The agent has a large number of hydrophobic end groups, each of which can be associated with the particles in the emulsion system to eventually form an intertwined three-dimensional network structure, which is denser and more stable than the network structure that can be formed by the rheology modifier with a star structure. The network structure formed by the association of the rheology modifier with a hyperbranched structure is interconnected and entangled. Under the shearing action of external force, it can greatly hinder the movement of particles along the direction of the external force, reduce the mobility of water and the flow rate of particles, thereby significantly increasing the viscosity of the emulsion system and playing a significant thickening role. In addition, this network structure formed by the association of hyperbranched structures greatly increases the fluid dynamic radius of the emulsion system. When the shear rate is low, the shear effect is not enough to destroy the network structure formed in the emulsion system, and the network structure remains intact. The water in the emulsion system fills the network structure, which significantly reduces the free water in the emulsion system and increases the viscosity. As the shear rate increases, excessive shear force causes gaps in the weak areas of the network structure, which is partially destroyed. As the shear continues, a larger range of structural damage is triggered. Therefore, the water in the network structure is released, and the emulsion system exhibits obvious shear thinning. As the shear force disappears, the network structure can gradually recover, and the viscosity of the emulsion system increases again, ultimately achieving the effect of maintaining a low viscosity of the emulsion at high shear and a high viscosity of the emulsion at low shear, reflecting the excellent thixotropic properties of the rheology modifier.

[0010] In the selection of polyethylene glycol molecular weight, the present invention particularly prefers polyethylene glycol 6000. Compared with commonly used polyethylene glycol 2000, polyethylene glycol 4000, polyethylene glycol 8000 and polyethylene glycol 10000, the present invention adopts polyethylene glycol 6000 as the soft segment of the polyurethane prepolymer, and the synthesized rheology modifier has better thickening effect. This is because the polyurethane prepolymer molecule is composed of soft segments and hard segments alternately embedded in the molecular skeleton, and the soft segment is determined by the molecular weight of polyethylene glycol. When the ratio of the soft segment to the hard segment is moderate, the thickening effect of the finally synthesized rheology modifier is best. When the molecular weight of polyethylene glycol is too small, such as polyethylene glycol 2000 and polyethylene glycol 4000, the hard segment occupies a large proportion in the molecular skeleton, resulting in reduced hydrophilicity of the synthesized rheology modifier, poor solubility in the emulsion system, and reduced thickening effect; when the molecular weight of polyethylene glycol is too large, such as polyethylene glycol 8000 and polyethylene glycol 10000, the soft segment occupies a large proportion in the molecular skeleton, and the hydrophilicity of the hydrophilic segment occupies a dominant position, breaking the association and disassociation balance of the rheology modifier in the emulsion system, resulting in difficulty in disassociation, which is directly manifested as the rheology modifier molecules entangled with each other into clusters and unable to be evenly dispersed in the emulsion system, resulting in a decrease in the thickening ability of the rheology modifier.

[0011] The hydrophilic segments of appropriate length can increase the water solubility of thickener molecules, improve the dispersion uniformity and stability of rheology modifiers in the emulsion system, and ultimately achieve the purpose of thickening. However, the thickening effect of rheology modifiers on aqueous emulsions is not only related to the length of the hydrophilic segments in the molecular structure, but also to the hydrophobic segments. The hydrophobic segments are in full contact with water molecules in the emulsion system, and the hydrophobic association effect is enhanced. The rheology modifier molecules in the emulsion system are intertwined and associated to form a network structure. Only when the hydrophobic segments at the end have appropriate length and shape can the rheology modifier molecules be associated and connected to form a perfect, dense and stable network structure that can effectively lock in moisture, thereby giving full play to its thickening ability. The present invention uses branched poly(1,4-butylene adipate) as a first end-capping agent and pentaerythritol triacrylate as a second end-capping agent to end-cap a hyperbranched intermediate, and obtains a rheology modifier having an ideal shape and length of a terminal hydrophobic segment through a grafting reaction between the hydroxyl groups on the first end-capping agent and the second end-capping agent and the isocyanate group at the end of the hyperbranched intermediate molecular chain. The first end-capping agent has a sufficient segment length and a sufficient number of branches, and can form micelles in an emulsion system to associate to form a perfect, dense and stable network structure, thereby significantly improving the thickening ability of the rheology modifier. In addition, the highly branched hydrophobic segment makes the molecular chains of the rheology modifier less entangled and not easy to crystallize, so that the coating can be endowed with a certain film-forming property. If unbranched poly(1,4-butylene adipate) is used, the hydrophobic association of the hydrophobic end groups is weakened due to the short hydrophobic segments and the small number of branches, and isolated hydrophobic association points are easily formed. The network structure formed by the staggered association between the association points is relatively simple, and a dense and stable association network structure cannot be formed, resulting in poor thickening effect. The present invention adds a second end-capping agent, pentaerythritol triacrylate, on the basis of the end-capping of branched poly(1,4-butylene adipate), wherein one end of the molecular chain of pentaerythritol triacrylate has a hydroxyl group and the other end has a double bond, and the hydroxyl group in the molecular structure of pentaerythritol triacrylate reacts with the isocyanate group in the hyperbranched intermediate, so that the end of the molecular chain of the hyperbranched intermediate has a double bond, thereby obtaining the ability to polymerize under ultraviolet light, so as to obtain a rheology modifier with photocuring ability.

[0012] As a preferred technical solution of the present invention, in step (I), the specific operation steps of the dehydration treatment of polyethylene glycol 6000 are as follows: The polyethylene glycol 6000 is heated to a melting temperature until the polyethylene glycol 6000 becomes liquid, and then the liquid polyethylene glycol 6000 is further heated to a dehydration temperature, and the reactor is evacuated until the vacuum degree in the reactor reaches the dehydration pressure, and the dehydration is maintained to complete the dehydration process.

[0013] In some optional examples, the melting temperature of the polyethylene glycol 6000 is 60-70°C, for example, it can be 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C or 70°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0014] In some optional examples, the dehydration temperature of the polyethylene glycol 6000 is 110-120°C, for example, it can be 110°C, 111°C, 112°C, 113°C, 114°C, 115°C, 116°C, 117°C, 118°C, 119°C or 120°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0015] In some optional examples, the dehydration pressure in the reactor is 0.08~0.09MPa, for example, it can be 0.08MPa, 0.081MPa, 0.082MPa, 0.083MPa, 0.084MPa, 0.085MPa, 0.086MPa, 0.087MPa, 0.088MPa, 0.089MPa or 0.09MPa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] In some optional examples, the dehydration treatment time is 3 to 5 hours, for example, it can be 3.0 hours, 3.2 hours, 3.4 hours, 3.6 hours, 3.8 hours, 4.0 hours, 4.2 hours, 4.4 hours, 4.6 hours, 4.8 hours or 5.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0017] As a preferred technical solution of the present invention, in step (I), the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate is 1:(1.8-2.3), for example, it can be 1:1.8, 1:1.85, 1:1.9, 1:1.95, 1:2.0, 1:2.05, 1:2.1, 1:2.15, 1:2.2, 1:2.25 or 1:2.3, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0018] The present invention particularly limits the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate to 1:(1.8-2.3). When the amount of polyethylene glycol 6000 is too much, the proportion of soft segments in the synthesized polyurethane prepolymer is relatively high, and the hydrophilicity is relatively strong, resulting in that the finally obtained rheology modifier has too high solubility in the emulsion system, and the hydrophobic segments cannot form micelles in the emulsion system, and also cannot associate to form a network structure, so that the thickening effect of the rheology modifier is deteriorated; when the amount of isophorone diisocyanate is too much, the proportion of hard segments in the synthesized polyurethane prepolymer is relatively high, and the hydrophobicity is relatively strong, resulting in that the finally obtained rheology modifier has too low solubility in the emulsion system, and even is difficult to dissolve in water, and finally the thickening effect is deteriorated. Therefore, only when the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate is within the numerical range specified in the present invention, can the soft segment and the hard segment in the synthesized polyurethane prepolymer reach a suitable ratio, so that the hydrophilic and hydrophobic effects of the rheology modifier are balanced, while having both thickening ability and water solubility.

[0019] In some optional examples, the heating temperature of the polyethylene glycol 6000 and isophorone diisocyanate is 80-90°C, for example, it can be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C or 90°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] In some optional examples, the heating time of polyethylene glycol 6000 and isophorone diisocyanate is 2 to 3 hours, for example, it can be 2.0 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours or 3.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0021] In some optional examples, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of 1,4-butanediol is 1:(0.04~0.05), for example, it can be 1:0.04, 1:0.0414, 1:0.0424, 1:0.0434, 1:0.0444, 1:0.0454, 1:0.0464, 1:0.0474, 1:0.0484, 1:0.0494 or 1:0.05, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0022] The present invention particularly limits the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass ratio of 1,4-butanediol to 1:(0.04-0.05). With the increase of the amount of 1,4-butanediol, the thickening effect of the finally synthesized rheology modifier shows a trend of first increasing and then decreasing. This is because, the greater the amount of 1,4-butanediol used, the higher the content of hydrophilic functional groups in the polyurethane prepolymer, the stronger its hydrophilicity and the higher its water solubility, which can promote the rheology modifier to be better dispersed in the emulsion system, and help to improve the thickening ability of the rheology modifier.

[0023] However, when the amount of 1,4-butanediol exceeds the upper limit of the range defined in the present invention, the hydrophilicity of the synthesized polyurethane prepolymer is too strong, resulting in the final rheology modifier having excessive solubility in the emulsion system, and the association between the hydrophobic segments of the rheology modifier is hindered, making it impossible to form micelles in the emulsion system, and also impossible to associate to form a complete and dense network structure, which makes the thickening effect of the rheology modifier worse.

[0024] In addition, 1,4-butanediol as a hydrophilic chain extender can change the molecular weight of the hydrophilic segment in the polyurethane prepolymer. When the amount of 1,4-butanediol used exceeds the upper limit of the range defined in the present invention, the molecular weight of the hydrophilic segment in the synthesized polyurethane prepolymer will be too large, which is not conducive to the dispersion of isophorone diisocyanate in the reaction system, resulting in local gelation in the polymerization reaction between polyethylene glycol 6000 and isophorone diisocyanate, reducing the controllability of the reaction, and the relative molecular mass of the synthesized polyurethane prepolymer is greatly different from the theoretical value, and the relative molecular mass distribution becomes wider, which ultimately leads to a reduction in the thickening effect of the rheology modifier.

[0025] In some optional examples, the heating temperature of the reaction solution and 1,4-butanediol is 70-80°C, for example, 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C or 80°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0026] In some optional examples, the heating time of the reaction solution and 1,4-butanediol is 4 to 5 hours, for example, 4.0 hours, 4.1 hours, 4.2 hours, 4.3 hours, 4.4 hours, 4.5 hours, 4.6 hours, 4.7 hours, 4.8 hours, 4.9 hours or 5.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0027] In some optional examples, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass ratio of triethanolamine is 1:(0.1~0.15), for example, it can be 1:0.1, 1:0.105, 1:0.11, 1:0.115, 1:0.12, 1:0.125, 1:0.13, 1:0.135, 1:0.14, 1:0.145 or 1:0.15, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0028] In some optional examples, the heating temperature of the first precursor solution and triethanolamine is 50-60°C, for example, it can be 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C or 60°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0029] In some optional examples, the heating time of the first precursor solution and triethanolamine is 4 to 5 hours, for example, it can be 4.0 hours, 4.1 hours, 4.2 hours, 4.3 hours, 4.4 hours, 4.5 hours, 4.6 hours, 4.7 hours, 4.8 hours, 4.9 hours or 5.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0030] In some optional examples, before adding dibutyltin dilaurate to the second precursor solution, an organic solvent is added to the second precursor solution to adjust the viscosity of the second precursor solution to 90~100mPa·s, for example, it can be 90mPa·s, 91mPa·s, 92mPa·s, 93mPa·s, 94mPa·s, 95mPa·s, 96mPa·s, 97mPa·s, 98mPa·s, 99mPa·s or 100mPa·s, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0031] In some optional examples, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass ratio of dibutyltin dilaurate is 100:(0.03~0.04), for example, it can be 100:0.03, 100:0.031, 100:0.032, 100:0.033, 100:0.034, 100:0.035, 100:0.036, 100:0.037, 100:0.038, 100:0.039 or 100:0.04, but is not limited to the listed values, and other unlisted values ​​within the numerical range are equally applicable.

[0032] In some optional examples, the heating temperature of the second precursor solution and dibutyltin dilaurate is 60-70°C, for example, it can be 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C or 70°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0033] In some optional examples, the mixing time of the second precursor solution and dibutyltin dilaurate is 4 to 5 hours, for example, it can be 4.0 hours, 4.1 hours, 4.2 hours, 4.3 hours, 4.4 hours, 4.5 hours, 4.6 hours, 4.7 hours, 4.8 hours, 4.9 hours or 5.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0034] As a preferred technical solution of the present invention, in step (II), when preparing the polyol intermediate, the molar ratio of trimethylolpropane to 2,2-dimethylolpropionic acid is 1:(3-3.2), for example, it can be 1:3.0, 1:3.02, 1:3.04, 1:3.06, 1:3.08, 1:3.1, 1:3.12, 1:3.14, 1:3.16, 1:3.18 or 1:3.2, but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0035] In some optional examples, when preparing the polyol intermediate, the mass ratio of p-toluenesulfonic acid to 2,2-dihydroxymethylpropionic acid is (0.008~0.012):1, for example, it can be 0.008:1, 0.0085:1, 0.009:1, 0.0095:1, 0.01:1, 0.0105:1, 0.011:1, 0.0115:1 or 0.012:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0036] In some optional examples, the reaction temperature of trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid is 140-150°C, for example, it can be 140°C, 141°C, 142°C, 143°C, 144°C, 145°C, 146°C, 147°C, 148°C, 149°C or 150°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0037] In some optional examples, when the acid value of the reaction product obtained by the reaction of trimethylolpropane, 2,2-dihydroxymethylpropionic acid and p-toluenesulfonic acid is ≤20 mgKOH / g, the reaction is stopped to obtain the polyol intermediate, for example, it can be 10 mgKOH / g, 11 mgKOH / g, 12 mgKOH / g, 13 mgKOH / g, 14 mgKOH / g, 15 mgKOH / g, 16 mgKOH / g, 17 mgKOH / g, 18 mgKOH / g, 19 mgKOH / g or 20 mgKOH / g, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0038] The more carboxyl content the reaction system has, the greater the acid value is. The change in acid value indicates the degree of esterification reaction. As the first generation of hyperbranched polyols, the polyol intermediate undergoes esterification reaction with dimethylolpropane and dimethylolpropionic acid during its synthesis. The acid value decreases with increasing reaction time. In the first 30 minutes or so, the acid value of the reaction system decreases very rapidly, and then the acid value decrease trend slows down. After 90 minutes, the acid value of the reaction system changes slowly. After 5 hours, the acid value of the reaction system is less than or equal to 20 mgKOH / g and tends to be stable, and the reaction is considered to be completed.

[0039] In some optional examples, when preparing the hyperbranched polyol, the molar ratio of the polyol intermediate to 2,2-dimethylolpropionic acid is 1:(6~6.2), for example, it can be 1:6.0, 1:6.02, 1:6.04, 1:6.06, 1:6.08, 1:6.1, 1:6.12, 1:6.14, 1:6.16, 1:6.18 or 1:6.2, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0040] In some optional examples, when preparing the hyperbranched polyol, the mass ratio of p-toluenesulfonic acid to 2,2-dimethylolpropionic acid is (0.008~0.012):1, for example, it can be 0.008:1, 0.0085:1, 0.009:1, 0.0095:1, 0.01:1, 0.0105:1, 0.011:1, 0.0115:1 or 0.012:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0041] In some optional examples, the reaction temperature of the polyol intermediate, 2,2-dihydroxymethylpropionic acid and p-toluenesulfonic acid is 140-150°C, for example, it can be 140°C, 141°C, 142°C, 143°C, 144°C, 145°C, 146°C, 147°C, 148°C, 149°C or 150°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0042] In some optional examples, when the acid value of the reaction product obtained by the reaction of the polyol intermediate, 2,2-dihydroxymethylpropionic acid and p-toluenesulfonic acid is ≤20 mgKOH / g, the reaction is stopped to obtain the hyperbranched polyol, for example, it can be 10 mgKOH / g, 11 mgKOH / g, 12 mgKOH / g, 13 mgKOH / g, 14 mgKOH / g, 15 mgKOH / g, 16 mgKOH / g, 17 mgKOH / g, 18 mgKOH / g, 19 mgKOH / g or 20 mgKOH / g, but it is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0043] As a preferred technical solution of the present invention, in step (II), the mass ratio of the prepolymer, hyperbranched polyol, 1,4-butanediol and acetone is 100:(8-12):(0.7-0.8):(15-20), for example, it can be 100:8:0.7:15, 100:8.5:0.71:15.5, 100:9:0.72:16, 100:9.5:0.73:16.5 , 100:10:0.74:17, 100:10.5:0.75:17.5, 100:11:0.76:18, 100:11.5:0.77:18.5, 100:12:0.78:19, 100:11:0.79:19.5 or 100:12:0.8:20, but are not limited to the listed values, other unlisted values ​​within the numerical range are also applicable.

[0044] The higher the branching degree of the rheology modifier, the more complex the branching structure, and the more complete network structure can be formed, which greatly improves the thickening effect of the rheology modifier. To this end, the present invention introduces a hyperbranched polyol into a polyurethane prepolymer, uses the hyperbranched polyol as a branching core, and contains a large number of hydroxyl groups on its molecular chain that can be used as grafting points. 1,4-butanediol is used as a small molecule chain extender, and acetone is used as a reaction system solvent. The isocyanate groups at the ends of the prepolymer molecular chains undergo a grafting reaction with the hydroxyl groups on the hyperbranched polyol, so that a large number of prepolymers are grafted onto the hyperbranched polyol molecules, and finally a hyperbranched intermediate containing a large number of branched structures is obtained, the hydrophobic association between the branches is strengthened, and the macromolecular chains can form a more complete spatial network structure through cross-linking, which greatly improves the thickening effect of the rheology modifier.

[0045] The present invention particularly defines the mass ratio of prepolymer, hyperbranched polyol, 1,4-butanediol and acetone as 100:(8-12):(0.7-0.8):(15-20). With the increase of the amount of hyperbranched polyol, the thickening effect of the finally synthesized rheology modifier shows a trend of first increasing and then decreasing. When the amount of hyperbranched polyol increases, the number of branched cores increases, the hydrophobic association effect is strengthened, and the thickening effect is improved. However, when the amount of hyperbranched polyol exceeds the upper limit of the range defined by the present invention, there is not enough prepolymer to be grafted therewith. The excess ungrafted hyperbranched polyol contains a large number of hydrophilic hydroxyl functional groups, which leads to a significant increase in the hydrophilicity of the finally synthesized rheology modifier, so that the hydrophobic chain segment at the end cannot form a complete network structure in the emulsion system, and the thickening effect is reduced.

[0046] In some optional examples, the heating temperature for the branching reaction of the prepolymer, hyperbranched polyol, 1,4-butanediol and acetone is 80-90°C, for example, 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C or 90°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0047] In some optional examples, the heating time for the branching reaction of the prepolymer, hyperbranched polyol, 1,4-butanediol and acetone is 1 to 3 hours, for example, it can be 1.0 h, 1.2 h, 1.4 h, 1.6 h, 1.8 h, 2.0 h, 2.2 h, 2.4 h, 2.6 h, 2.8 h or 3.0 h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0048] As a preferred technical solution of the present invention, in step (III), the branched poly(1,4-butylene adipate) is prepared by the following method: Adipic acid, 1,4-butanediol, trihydroxymethylphosphine oxide and p-toluenesulfonic acid are added to a reactor, nitrogen is introduced into the reactor, and adipic acid, 1,4-butanediol, trihydroxymethylphosphine oxide and p-toluenesulfonic acid are mixed, stirred and heated under a nitrogen atmosphere to cause an esterification reaction to obtain an esterification product; then, the reactor is evacuated until the vacuum degree in the reactor reaches a pre-polycondensation pressure, a composite catalyst is added to the esterification product, mixed, stirred and heated to cause a pre-polycondensation reaction, and then the reactor is continuously evacuated until the vacuum degree in the reactor reaches a polycondensation pressure, and mixed, stirred and heated under the polycondensation pressure to cause a polycondensation reaction, and after the reaction is completed, the branched polyadipate-1,4-butanediol ester is obtained.

[0049] As a preferred technical solution of the present invention, when preparing branched poly adipate-1,4-butanediol ester, the molar ratio of adipic acid to 1,4-butanediol is 1:(1.2~1.3), for example, it can be 1:1.2, 1:1.21, 1:1.22, 1:1.23, 1:1.24, 1:1.25, 1:1.26, 1:1.27, 1:1.28, 1:1.29 or 1:1.3, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0050] In some optional examples, the mass ratio of trihydroxymethylphosphine oxide to 1,4-butanediol is (0.025~0.035):1, for example, it can be 0.025:1, 0.026:1, 0.027:1, 0.028:1, 0.029:1, 0.03:1, 0.031:1, 0.032:1, 0.033:1, 0.034:1 or 0.035:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0051] In some optional examples, the mass ratio of the total mass of adipic acid and 1,4-butanediol to the mass ratio of p-toluenesulfonic acid is 100:(0.03~0.05), for example, it can be 100:0.03, 100:0.032, 100:0.034, 100:0.036, 100:0.038, 100:0.04, 100:0.042, 100:0.044, 100:0.046, 100:0.048 or 100:0.05, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0052] In some optional examples, the temperature of the esterification reaction of adipic acid, 1,4-butanediol, trihydroxymethylphosphine oxide and p-toluenesulfonic acid is 150-180°C, for example, it can be 150°C, 152°C, 154°C, 156°C, 158°C, 160°C, 162°C, 164°C, 166°C, 168°C, 170°C, 172°C, 174°C, 176°C, 178°C or 180°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0053] In some optional examples, when the acid value of the reaction product obtained by the esterification reaction is ≤10 mgKOH / g, the esterification reaction is terminated to obtain the esterification product, for example, it can be 8.0 mgKOH / g, 8.2 mgKOH / g, 8.4 mgKOH / g, 8.6 mgKOH / g, 8.8 mgKOH / g, 9.0 mgKOH / g, 9.2 mgKOH / g, 9.4 mgKOH / g, 9.6 mgKOH / g, 9.8 mgKOH / g or 10.0 mgKOH / g, but it is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0054] In some optional examples, the pre-condensation pressure is 600~800Pa, for example, it can be 600Pa, 620Pa, 640Pa, 660Pa, 680Pa, 700Pa, 720Pa, 740Pa, 760Pa, 780Pa or 800Pa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0055] In some optional examples, the ratio of the total mass of the adipic acid and 1,4-butanediol to the mass of the composite catalyst is 100:(0.01~0.02), for example, it can be 100:0.01, 100:0.011, 100:0.012, 100:0.013, 100:0.014, 100:0.015, 100:0.016, 100:0.017, 100:0.018, 100:0.019 or 100:0.02, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0056] In some optional examples, the composite catalyst is composed of tetrabutyl titanate and tetraisopropyl titanate, wherein the mass ratio of tetrabutyl titanate to tetraisopropyl titanate is (3~4):1, for example, it can be 3.0:1, 3.1:1, 3.2:1, 3.3:1, 3.4:1, 3.5:1, 3.6:1, 3.7:1, 3.8:1, 3.9:1 or 4.0:1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0057] In some optional embodiments, the heating temperature of the pre-condensation reaction is 200-220°C, for example, it can be 200°C, 202°C, 204°C, 206°C, 208°C, 210°C, 212°C, 214°C, 216°C, 218°C or 220°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0058] In some optional examples, the heating time of the pre-condensation reaction is 1 to 2 hours, for example, it can be 1.0h, 1.1h, 1.2h, 1.3h, 1.4h, 1.5h, 1.6h, 1.7h, 1.8h, 1.9h or 2.0h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0059] In some optional examples, the condensation pressure is 100~150Pa, for example, it can be 100Pa, 105Pa, 110Pa, 115Pa, 120Pa, 125Pa, 130Pa, 135Pa, 140Pa, 145Pa or 150Pa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0060] In some optional embodiments, the heating temperature of the condensation reaction is 230~250℃, for example, it can be 230℃, 232℃, 234℃, 236℃, 238℃, 240℃, 242℃, 244℃, 246℃, 248℃ or 250℃, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0061] In some optional examples, the heating time of the polycondensation reaction is 5 to 6 hours, for example, it can be 5.0 hours, 5.1 hours, 5.2 hours, 5.3 hours, 5.4 hours, 5.5 hours, 5.6 hours, 5.7 hours, 5.8 hours, 5.9 hours or 6.0 hours, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0062] As a preferred technical solution of the present invention, in step (III), the mass ratio of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is 100:(3-4):(20-30):(0.2-0.3), for example, it can be 100:3:20:0.2, 100:3.1:21:0.21, 100:3.2:22:0.22, 100:3 .3:23:0.23, 100:3.4:24:0.24, 100:3.5:25:0.25, 100:3.6:26:0.26, 100:3.7:27:0.27, 100:3.8:28:0.28, 100:3.9:29:0.29 or 100:4:30:0.3, but are not limited to the listed values, other values ​​not listed within the numerical range are also applicable.

[0063] The present invention particularly defines the mass ratio of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol as 100:(3-4):(20-30):(0.2-0.3). When the amount of pentaerythritol triacrylate exceeds the upper limit of the range defined by the present invention, the particle size of the aqueous emulsion will continue to increase and the particle size distribution will become wider. This is because pentaerythritol triacrylate is a trifunctional molecule, and the increase in the double bond ratio enhances the adsorption between the end-capped rheology modifier molecules, increases the intermolecular force, and further increases the viscosity of the rheology modifier. During shear emulsification, the dispersion resistance of the rheology modifier in the aqueous emulsion increases, resulting in an increase in the particle size of the aqueous emulsion finally obtained, which is prone to sedimentation and ultimately affects its thickening ability and rheological properties.

[0064] In some optional examples, the heating temperature for the end-capping reaction of the hyperbranched intermediate, branched poly(1,4-butanediol adipate), pentaerythritol triacrylate and p-methoxyphenol is 80-90°C, for example, it can be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C or 90°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0065] In some optional examples, the heating time for the end-capping reaction of the hyperbranched intermediate, branched poly(1,4-butanediol adipate), pentaerythritol triacrylate and p-methoxyphenol is 2 to 3 hours, for example, it can be 2.0 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.7 hours, 2.8 hours, 2.9 hours or 3.0 hours, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0066] In some optional examples, after the end-capping reaction is completed, the intermediate product obtained by the reaction is cooled to 40-50°C, for example, 40°C, 41°C, 42°C, 43°C, 44°C, 45°C, 46°C, 47°C, 48°C, 49°C or 50°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0067] In some optional examples, the neutralizer solution consists of a neutralizer and deionized water.

[0068] In some optional examples, the concentration of the neutralizer in the neutralizer solution is 0.2~0.3mol / L, for example, it can be 0.2mol / L, 0.21mol / L, 0.22mol / L, 0.23mol / L, 0.24mol / L, 0.25mol / L, 0.26mol / L, 0.27mol / L, 0.28mol / L, 0.29mol / L or 0.3mol / L, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0069] In some optional examples, the neutralizing agent includes any one of diethylamine, triethylamine, diisopropylethylamine or dimethylethanolamine, or a combination of at least two thereof.

[0070] In some optional examples, the mass ratio of the intermediate product to the neutralizer in the neutralizer solution is 1:(0.08~0.1), for example, it can be 1:0.08, 1:0.082, 1:0.084, 1:0.086, 1:0.088, 1:0.09, 1:0.092, 1:0.094, 1:0.096, 1:0.098 or 1:0.1, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0071] In some optional examples, the rotation speed of the high-speed stirring is 2000~3000r / min, for example, it can be 2000r / min, 2100r / min, 2200r / min, 2300r / min, 2400r / min, 2500r / min, 2600r / min, 2700r / min, 2800r / min, 2900r / min or 3000r / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0072] In some optional examples, the high-speed stirring time is 1 to 2 hours, for example, it can be 1.0h, 1.1h, 1.2h, 1.3h, 1.4h, 1.5h, 1.6h, 1.7h, 1.8h, 1.9h or 2.0h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0073] In a second aspect, the present invention provides a hyperbranched polyurethane associative rheology modifier, wherein the rheology modifier is prepared by the preparation method of a hyperbranched polyurethane associative rheology modifier described in the first aspect.

[0074] In a third aspect, the present invention provides a water-based coating, comprising an emulsion, a film-forming aid, a defoaming agent, a rheology modifier and deionized water, wherein the rheology modifier is the hyperbranched polyurethane associative rheology modifier described in the second aspect.

[0075] Compared with the prior art, the present invention has the following beneficial effects: The invention uses polyethylene glycol 6000 as a soft segment, an excess of isophorone diisocyanate as a hard segment, and 1,4-butanediol as a hydrophilic small molecule chain extender, and reacts under the catalytic action of dibutyltin dilaurate to generate an isocyanate-terminated prepolymer with a hydrophilic segment, wherein the introduction of 1,4-butanediol can increase the proportion of hydrophilic functional groups in the hydrophilic segment, which is beneficial to improving the dispersibility of the rheology modifier in the aqueous emulsion; subsequently, the invention uses a second-generation hyperbranched polyol as a branched core, and the hyperbranched structure in the prepared hyperbranched polyol is controllable, and the number of hyperbranching iterations can be adjusted according to different ratios of raw materials, so as to provide more reaction functional groups for subsequent end-capping reactions, and utilizes the large number of hyperbranched polyols on the hyperbranched polyols to obtain a controllable hyperbranched structure. The reaction characteristics of a large amount of hydroxyl groups with the isocyanate groups at the ends of the prepolymer molecular chains are used to branch and extend the prepolymer to obtain a hyperbranched intermediate. The introduction of hyperbranched polyols makes the branched structure more complicated. Finally, branched poly(1,4-butylene adipate) and pentaerythritol triacrylate are used as hydrophobic segments, and the reaction characteristics of the hydroxyl groups at the ends of the branched poly(1,4-butylene adipate) and pentaerythritol triacrylate molecular chains with the isocyanate groups at the ends of the hyperbranched intermediates are used to perform end-capping to prepare a rheology modifier. Due to the hydrophobic association between the hydrophobic segments of the rheology modifier, the macromolecular chains can form a more complete spatial network structure through cross-linking, which greatly improves the thickening ability and rheological properties of the rheology modifier for the aqueous emulsion system. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 A process flow chart of the preparation of a hyperbranched polyurethane associative rheology modifier provided in Examples 1 to 5 of the present invention; Figure 2 This is the infrared spectrum of the hyperbranched polyol prepared in Example 1 of the present invention; Figure 3 This is the infrared spectrum of the branched poly(1,4-butylene adipate) prepared in Example 1 of the present invention; Figure 4 This is the energy spectrum of the branched poly(1,4-butylene adipate) prepared in Example 1 of the present invention; Figure 5 This is the infrared spectrum of the rheology modifier prepared in Example 1 of the present invention; Figure 6 The rotation speed-viscosity change curves of the water-based coatings prepared in Example 1 and Comparative Example 9 of the present invention; Figure 7 This is a surface electron microscope image of a coating made of the rheology modifier prepared in Example 1 of the present invention; Figure 8 This is a cross-sectional electron micrograph of a coating made using the rheology modifier prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0077] The technical solution of the present invention is described in detail below in conjunction with specific embodiments and their accompanying drawings. The embodiments recorded herein are specific embodiments of the present invention, which are used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary and should not be construed as limitations on the embodiments of the present invention and the scope of protection of the present invention. In addition to the embodiments recorded herein, those skilled in the art can also adopt other obvious technical solutions based on the contents disclosed in the claims of this application and its specification, including technical solutions that adopt any obvious replacements and modifications to the embodiments recorded herein.

[0078] The chemical reagents used in the specific implementation are all commercially available products, and their models, specifications, manufacturers and other information are as follows: Polyethylene glycol 6000: purity ≥99.9%, purchased from Jinan Jinrihe Chemical Co., Ltd.; Isophorone diisocyanate: purity ≥99%, purchased from Shanghai Fanaxu Import and Export Co., Ltd.; 1,4-Butanediol: S24138-500ml, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; Triethanolamine: industrial grade, Nantong Runfeng Petrochemical Co., Ltd.; N, N-dimethylformamide: purity ≥99.5%, Fuchen (Tianjin) Chemical Reagent Co., Ltd.; Dibutyltin dilaurate: purity ≥99.5%, Jinan Century Tongda Chemical Co., Ltd.; Trimethylolpropane: S50717-100g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; 2,2-Dihydroxymethylpropionic acid: S24027-500g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; p-Toluenesulfonic acid: purity ≥99%, purchased from Shandong Yukang Chemical Co., Ltd.; Acetone: purity ≥99.5%, Fuchen (Tianjin) Chemical Reagent Co., Ltd.; Adipic acid: S30144-500g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; Trihydroxymethylphosphine oxide: purity ≥99%, purchased from Hubei Qifei Pharmaceutical Chemical Co., Ltd.; Tetrabutyl titanate: S48406-500ml, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; Tetraisopropyl titanate: purity ≥99%, purchased from Wuhan Jixinyibang Biotechnology Co., Ltd.; Pentaerythritol triacrylate: S64762-25g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; p-Methoxyphenol: S30255-100g, purchased from Shanghai Yuanye Biotechnology Co., Ltd.; Diethylamine: purity ≥99.5%, purchased from Shandong Jinyueyuan New Materials Co., Ltd.; Triethylamine: purity ≥99.9%, purchased from Shandong Langcheng Chemical Co., Ltd.; Diisopropylethylamine: purity ≥99%, purchased from Shanghai Kaisai Chemical Co., Ltd.; Dimethylethanolamine: purity ≥99.8%, purchased from Jinan Century Tongda Chemical Co., Ltd.

[0079] Example 1

[0080] This embodiment provides a method for preparing a hyperbranched polyurethane associative rheology modifier, such as Figure 1 As shown, the preparation method comprises: Step (1), adding polyethylene glycol 6000 into a reaction kettle, heating the polyethylene glycol 6000 to 60° C. until the polyethylene glycol 6000 becomes liquid, then continuing to heat the liquid polyethylene glycol 6000 to 110° C., and evacuating the reaction kettle until the vacuum degree in the reaction kettle reaches 0.09 MPa, and maintaining the vacuum for 5 hours to complete the dehydration treatment; Nitrogen was introduced into the reaction kettle, and in the nitrogen atmosphere, isophorone diisocyanate was added to the dehydrated polyethylene glycol 6000, the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate was 1:1.8, and the mixture was mixed and stirred at 80° C. for 3 h to obtain a reaction solution; Add 1,4-butanediol, polyethylene glycol 6000 and isophorone diisocyanate to the reaction solution in a ratio of 1:0.04, and mix and stir at 70° C. for 5 h to obtain a first precursor solution; Add triethanolamine to the first precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of triethanolamine is 1:0.1, mix and stir at 50° C. for 5 hours to obtain a second precursor solution; N,N-dimethylformamide was added to the second precursor solution to adjust the viscosity of the second precursor solution to 90 mPa·s, and then dibutyltin dilaurate was added to the second precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of dibutyltin dilaurate was 100:0.03, and the mixture was mixed and stirred at 60° C. for 5 h to obtain a prepolymer terminated by an isocyanate group; Step (2), under a nitrogen atmosphere, trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed, wherein the molar ratio of trimethylolpropane to 2,2-dimethylolpropionic acid is 1:3, and the mass ratio of p-toluenesulfonic acid to 2,2-dimethylolpropionic acid is 0.008:1, and the mixture is stirred at 140° C. to react, and when the acid value of the reaction product reaches 18 mgKOH / g, the reaction is stopped to obtain a polyol intermediate; Mixing a polyol intermediate, 2,2-dimethylol propionic acid and p-toluenesulfonic acid, wherein the molar ratio of the polyol intermediate to the 2,2-dimethylol propionic acid is 1:6, and the mass ratio of the p-toluenesulfonic acid to the 2,2-dimethylol propionic acid is 0.008:1, stirring and mixing at 140° C. to react, and stopping the reaction when the acid value of the reaction product reaches 18 mgKOH / g to obtain a hyperbranched polyol; Adding a hyperbranched polyol, 1,4-butanediol and acetone to the prepolymer obtained in step (1), wherein the mass ratio of the prepolymer, the hyperbranched polyol, the 1,4-butanediol and the acetone is 100:8:0.7:15, mixing and stirring at 80° C. for 3 h to cause a branching reaction, and obtaining a hyperbranched intermediate after the reaction is completed; Step (3), adding adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid into a reaction kettle, wherein the molar ratio of adipic acid to 1,4-butanediol is 1:1.2, the mass ratio of trimethylolphosphine oxide to 1,4-butanediol is 0.025:1, and the mass ratio of the total mass of adipic acid and 1,4-butanediol to the mass of p-toluenesulfonic acid is 100:0.03, introducing nitrogen into the reaction kettle, mixing and stirring adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid under a nitrogen atmosphere at 150° C. and heating to cause an esterification reaction, and when the acid value of the reaction product reaches 8 mgKOH / g, the esterification reaction is terminated to obtain an esterified product; Subsequently, the reactor was evacuated until the vacuum degree in the reactor reached 600 Pa, a composite catalyst was added to the esterification product, the total mass ratio of adipic acid and 1,4-butanediol to the mass ratio of the composite catalyst was 100:0.01, the composite catalyst was composed of tetrabutyl titanate and tetraisopropyl titanate in a mass ratio of 3:1, mixed and stirred at 200° C. for 2 h to cause a pre-polycondensation reaction, and then the reactor was continuously evacuated until the vacuum degree in the reactor reached 100 Pa, and mixed and stirred at 100 Pa and 230° C. for 6 h to cause a polycondensation reaction, and branched polyadipate-1,4-butanediol was obtained after the reaction was completed; Add branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol to the hyperbranched intermediate obtained in step (2), wherein the mass ratio of the hyperbranched intermediate, the branched poly(1,4-butylene adipate), the pentaerythritol triacrylate and the p-methoxyphenol is 100:3:20:0.2, and mix and stir at 80° C. for 3 h to cause a capping reaction. After the reaction, an intermediate product is obtained. The intermediate product is cooled to 40° C., and then a diethylamine solution with a concentration of 0.2 mol / L is added to the intermediate product under stirring at a speed of 2000 r / min for emulsification. The mass ratio of the intermediate product to the diethylamine in the diethylamine solution is 1:0.08. After high-speed stirring for 2 h, the hyperbranched polyurethane associative rheology modifier is obtained.

[0081] Figure 2 This is the infrared spectrum of the hyperbranched polyol prepared in this example. As can be seen from the figure, 3437 cm -1 The stretching vibration absorption peak of -OH is at 2929cm, which indicates that there are completely hydrogen-bonded hydroxyl groups on the hyperbranched polyol molecules synthesized in Example 1, and there are a large number of hydroxyl groups in the product system; -1 and 2853cm -1 The stretching vibration absorption peak of CH is 705cm -1 The vibration absorption peak of methylene is 1732cm -1 The carbonyl vibration absorption peak is at 1126cm -1 and 1046cm -1 The symmetric and asymmetric stretching vibration absorption peaks of CO are 1279 cm -1 It is the characteristic peak of COC ester group. The appearance of the above characteristic peak indicates that the obtained product is a hyperbranched polyol.

[0082] Figure 3 This is the infrared spectrum of the branched poly(1,4-butylene adipate) prepared in this example. As can be seen from the figure, 1170 cm -1 and 1730cm -1 The stretching vibration absorption peaks of the carbon-oxygen (CO) single bond and the carbon-oxygen double bond (C=O) in the ester group are at 2957 cm -1 The stretching vibration absorption peak of methylene (-CH2) is 3447cm -1 The peak at the center is the stretching vibration absorption peak of the terminal hydroxyl group. The appearance of the above characteristic peaks indicates that the obtained product is branched poly(1,4-butylene adipate).

[0083] Figure 4This is the energy spectrum of the branched poly(1,4-butylene adipate) prepared in this example. It can be seen from the figure that the product contains carbon, oxygen and phosphorus elements, indicating that trimethylolphosphine oxide participates in the reaction to generate branched poly(1,4-butylene adipate).

[0084] Figure 5 This is the infrared spectrum of the rheology modifier prepared in this example. It can be seen from the figure that 2270cm -1 There is no obvious characteristic absorption peak of isocyanate group at 3338cm -1 and 1536cm -1 The stretching vibration peak and deformation vibration peak of NH bond in carbamate appeared at 1716cm -1 The stretching vibration absorption peak of C=O bond in carbamate appeared at , which indicates that isocyanate reacts with hydroxyl groups in branched poly(1,4-butylene adipate) and pentaerythritol triacrylate molecules to generate carbamate, and branched poly(1,4-butylene adipate) and pentaerythritol triacrylate are introduced into the molecular structure of the rheology modifier as hydrophobic segments.

[0085] Example 2

[0086] This embodiment provides a method for preparing a hyperbranched polyurethane associative rheology modifier, such as Figure 1 As shown, the preparation method comprises: Step (1), adding polyethylene glycol 6000 into a reaction kettle, heating the polyethylene glycol 6000 to 62° C. until the polyethylene glycol 6000 becomes liquid, then continuing to heat the liquid polyethylene glycol 6000 to 112° C., and evacuating the reaction kettle until the vacuum degree in the reaction kettle reaches 0.088 MPa, and maintaining the vacuum for 4.5 hours to complete the dehydration treatment; Nitrogen was introduced into the reaction kettle. In the nitrogen atmosphere, isophorone diisocyanate was added to the dehydrated polyethylene glycol 6000, the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate was 1:1.9, and the mixture was mixed and stirred at 82° C. for 2.8 h to obtain a reaction solution. Add 1,4-butanediol, polyethylene glycol 6000 and isophorone diisocyanate to the reaction solution in a mass ratio of 1:0.042 to 1,4-butanediol, and mix and stir at 72° C. for 4.8 hours to obtain a first precursor solution; Add triethanolamine to the first precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of triethanolamine is 1:0.11, mix and stir at 52° C. for 4.8 h to obtain a second precursor solution; N,N-dimethylformamide was added to the second precursor solution to adjust the viscosity of the second precursor solution to 92 mPa·s, and then dibutyltin dilaurate was added to the second precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of dibutyltin dilaurate was 100:0.032, and the mixture was mixed and stirred at 62° C. for 4.8 h to obtain a prepolymer terminated by an isocyanate group; Step (2), under a nitrogen atmosphere, trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed, wherein the molar ratio of trimethylolpropane to 2,2-dimethylolpropionic acid is 1:3.05, and the mass ratio of p-toluenesulfonic acid to 2,2-dimethylolpropionic acid is 0.009:1, and the mixture is stirred at 142° C. to react, and when the acid value of the reaction product reaches 18.5 mgKOH / g, the reaction is stopped to obtain a polyol intermediate; A polyol intermediate, 2,2-dimethylol propionic acid and p-toluenesulfonic acid are mixed, wherein the molar ratio of the polyol intermediate to the 2,2-dimethylol propionic acid is 1:6.05, and the mass ratio of the p-toluenesulfonic acid to the 2,2-dimethylol propionic acid is 0.009:1, and the mixture is stirred at 142° C. to react, and when the acid value of the reaction product reaches 18.5 mgKOH / g, the reaction is stopped to obtain a hyperbranched polyol; Adding a hyperbranched polyol, 1,4-butanediol and acetone to the prepolymer obtained in step (1), wherein the mass ratio of the prepolymer, the hyperbranched polyol, the 1,4-butanediol and the acetone is 100:9:0.72:16, and mixing and stirring at 82° C. for 2.5 h to cause a branching reaction, and obtaining a hyperbranched intermediate after the reaction is completed; Step (3), adding adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid into a reaction kettle, wherein the molar ratio of adipic acid to 1,4-butanediol is 1:1.22, the mass ratio of trimethylolphosphine oxide to 1,4-butanediol is 0.028:1, and the mass ratio of the total mass of adipic acid and 1,4-butanediol to p-toluenesulfonic acid is 100:0.035, introducing nitrogen into the reaction kettle, mixing and stirring adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid under a nitrogen atmosphere at 160° C. and heating to cause an esterification reaction, and when the acid value of the reaction product reaches 8.5 mgKOH / g, the esterification reaction is terminated to obtain an esterified product; Subsequently, the reactor was evacuated until the vacuum degree in the reactor reached 650Pa, a composite catalyst was added to the esterification product, the total mass ratio of adipic acid and 1,4-butanediol to the mass ratio of the composite catalyst was 100:0.012, the composite catalyst was composed of tetrabutyl titanate and tetraisopropyl titanate in a mass ratio of 3.2:1, mixed and stirred at 205°C for 1.8h to cause a pre-polycondensation reaction, and then the reactor was continuously evacuated until the vacuum degree in the reactor reached 110Pa, and mixed and stirred at 110Pa and 235°C for 5.8h to cause a polycondensation reaction, and branched polyadipate-1,4-butanediol was obtained after the reaction was completed; To the hyperbranched intermediate obtained in step (2), branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol are added, wherein the mass ratio of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is 100:3.2:22:0.22, and the mixture is mixed and stirred at 82° C. for 2.8 h to cause a capping reaction. After the reaction, an intermediate product is obtained. The intermediate product is cooled to 42° C., and then a triethylamine solution with a concentration of 0.22 mol / L is added to the intermediate product under stirring at a speed of 2200 r / min for emulsification. The mass ratio of the intermediate product to the triethylamine in the triethylamine solution is 1:0.085. The hyperbranched polyurethane associative rheology modifier is obtained after high-speed stirring for 1.8 h.

[0087] Example 3

[0088] This embodiment provides a method for preparing a hyperbranched polyurethane associative rheology modifier, such as Figure 1 As shown, the preparation method comprises: Step (1), adding polyethylene glycol 6000 into a reaction kettle, heating the polyethylene glycol 6000 to 65° C. until the polyethylene glycol 6000 becomes liquid, then continuing to heat the liquid polyethylene glycol 6000 to 115° C., and evacuating the reaction kettle until the vacuum degree in the reaction kettle reaches 0.085 MPa, and maintaining the vacuum for 4 hours to complete the dehydration treatment; Nitrogen was introduced into the reaction kettle. In the nitrogen atmosphere, isophorone diisocyanate was added to the dehydrated polyethylene glycol 6000, the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate was 1:2, and the mixture was mixed and stirred at 85° C. for 2.5 h to obtain a reaction solution. Add 1,4-butanediol, polyethylene glycol 6000 and isophorone diisocyanate to the reaction solution in a ratio of 1:0.045, and mix and stir at 75° C. for 4.5 hours to obtain a first precursor solution; Add triethanolamine to the first precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of triethanolamine is 1:0.12, mix and stir at 55° C. for 4.5 hours to obtain a second precursor solution; N,N-dimethylformamide was added to the second precursor solution to adjust the viscosity of the second precursor solution to 95 mPa·s, and then dibutyltin dilaurate was added to the second precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of dibutyltin dilaurate was 100:0.035, and the mixture was mixed and stirred at 65° C. for 4.5 hours to obtain a prepolymer terminated by an isocyanate group; Step (2), under a nitrogen atmosphere, trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed, wherein the molar ratio of trimethylolpropane to 2,2-dimethylolpropionic acid is 1:3.1, and the mass ratio of p-toluenesulfonic acid to 2,2-dimethylolpropionic acid is 0.01:1, and the mixture is stirred at 145° C. to react, and when the acid value of the reaction product reaches 19 mgKOH / g, the reaction is stopped to obtain a polyol intermediate; Mixing a polyol intermediate, 2,2-dimethylol propionic acid and p-toluenesulfonic acid, wherein the molar ratio of the polyol intermediate to the 2,2-dimethylol propionic acid is 1:6.1, and the mass ratio of the p-toluenesulfonic acid to the 2,2-dimethylol propionic acid is 0.01:1, stirring and mixing at 145° C. to react, and stopping the reaction when the acid value of the reaction product reaches 19 mgKOH / g to obtain a hyperbranched polyol; Adding a hyperbranched polyol, 1,4-butanediol and acetone to the prepolymer obtained in step (1), wherein the mass ratio of the prepolymer, the hyperbranched polyol, the 1,4-butanediol and the acetone is 100:10:0.75:17, mixing and stirring at 85° C. for 2 h to cause a branching reaction, and obtaining a hyperbranched intermediate after the reaction is completed; Step (3), adding adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid into a reaction kettle, wherein the molar ratio of adipic acid to 1,4-butanediol is 1:1.25, the mass ratio of trimethylolphosphine oxide to 1,4-butanediol is 0.03:1, and the mass ratio of the total mass of adipic acid and 1,4-butanediol to the mass of p-toluenesulfonic acid is 100:0.04, introducing nitrogen into the reaction kettle, mixing and stirring adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid under a nitrogen atmosphere at 170° C. and heating to cause an esterification reaction, and when the acid value of the reaction product reaches 9 mgKOH / g, the esterification reaction is terminated to obtain an esterified product; Subsequently, the reactor was evacuated until the vacuum degree in the reactor reached 700 Pa, and a composite catalyst was added to the esterification product, the total mass ratio of adipic acid and 1,4-butanediol to the mass ratio of the composite catalyst was 100:0.015, and the composite catalyst was composed of tetrabutyl titanate and tetraisopropyl titanate in a mass ratio of 3.5:1, and mixed and stirred for 1.5 hours at 210° C. to cause a pre-polycondensation reaction, and then the reactor was continuously evacuated until the vacuum degree in the reactor reached 120 Pa, and mixed and stirred for 5.5 hours at 120 Pa and 240° C. to cause a polycondensation reaction, and branched polyadipate-1,4-butanediol was obtained after the reaction was completed; To the hyperbranched intermediate obtained in step (2), branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol are added, wherein the mass ratio of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is 100:3.5:25:0.25, and the mixture is mixed and stirred at 85° C. for 2.5 hours to cause a capping reaction. After the reaction, an intermediate product is obtained. The intermediate product is cooled to 45° C., and then a diisopropylethylamine solution with a concentration of 0.25 mol / L is added to the intermediate product under stirring at a speed of 2500 r / min for emulsification. The mass ratio of the intermediate product to the diisopropylethylamine in the diisopropylethylamine solution is 1:0.09. The hyperbranched polyurethane associative rheology modifier is obtained after high-speed stirring for 1.5 hours.

[0089] Example 4

[0090] This embodiment provides a method for preparing a hyperbranched polyurethane associative rheology modifier, such as Figure 1 As shown, the preparation method comprises: Step (1), adding polyethylene glycol 6000 into a reaction kettle, heating the polyethylene glycol 6000 to 68° C. until the polyethylene glycol 6000 becomes liquid, then continuing to heat the liquid polyethylene glycol 6000 to 118° C., and evacuating the reaction kettle until the vacuum degree in the reaction kettle reaches 0.082 MPa, and maintaining the vacuum for 3.5 hours to complete the dehydration treatment; Nitrogen was introduced into the reaction kettle. In the nitrogen atmosphere, isophorone diisocyanate was added to the dehydrated polyethylene glycol 6000, the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate was 1:2.2, and the mixture was mixed and stirred at 88° C. for 2.2 h to obtain a reaction solution. Add 1,4-butanediol, polyethylene glycol 6000 and isophorone diisocyanate to the reaction solution in a mass ratio of 1:0.048 to 1,4-butanediol, and mix and stir at 78° C. for 4.2 h to obtain a first precursor solution; Add triethanolamine to the first precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of triethanolamine is 1:0.13, mix and stir at 58° C. for 4.2 h to obtain a second precursor solution; N,N-dimethylformamide was added to the second precursor solution to adjust the viscosity of the second precursor solution to 98 mPa·s, and then dibutyltin dilaurate was added to the second precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of dibutyltin dilaurate was 100:0.038, and the mixture was mixed and stirred at 68° C. for 4.2 h to obtain a prepolymer terminated by an isocyanate group; Step (2), under a nitrogen atmosphere, trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed, wherein the molar ratio of trimethylolpropane to 2,2-dimethylolpropionic acid is 1:3.15, and the mass ratio of p-toluenesulfonic acid to 2,2-dimethylolpropionic acid is 0.011:1, and the mixture is stirred at 148° C. to react, and when the acid value of the reaction product reaches 19.5 mgKOH / g, the reaction is stopped to obtain a polyol intermediate; A polyol intermediate, 2,2-dimethylol propionic acid and p-toluenesulfonic acid are mixed, wherein the molar ratio of the polyol intermediate to the 2,2-dimethylol propionic acid is 1:6.15, and the mass ratio of the p-toluenesulfonic acid to the 2,2-dimethylol propionic acid is 0.011:1, and the mixture is stirred at 148° C. to react, and when the acid value of the reaction product reaches 19.5 mgKOH / g, the reaction is stopped to obtain a hyperbranched polyol; Adding a hyperbranched polyol, 1,4-butanediol and acetone to the prepolymer obtained in step (1), wherein the mass ratio of the prepolymer, the hyperbranched polyol, the 1,4-butanediol and the acetone is 100:11:0.78:18, and mixing and stirring at 88° C. for 1.5 h to cause a branching reaction, and obtaining a hyperbranched intermediate after the reaction is completed; Step (3), adding adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid into a reaction kettle, wherein the molar ratio of adipic acid to 1,4-butanediol is 1:1.28, the mass ratio of trimethylolphosphine oxide to 1,4-butanediol is 0.032:1, and the mass ratio of the total mass of adipic acid and 1,4-butanediol to the mass of p-toluenesulfonic acid is 100:0.045, introducing nitrogen into the reaction kettle, mixing and stirring adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid under a nitrogen atmosphere at 170° C. and heating to cause an esterification reaction, and when the acid value of the reaction product reaches 9.5 mgKOH / g, the esterification reaction is terminated to obtain an esterified product; Subsequently, the reactor was evacuated until the vacuum degree in the reactor reached 750Pa, and a composite catalyst was added to the esterification product, the total mass ratio of adipic acid and 1,4-butanediol to the mass ratio of the composite catalyst was 100:0.018, and the composite catalyst was composed of tetrabutyl titanate and tetraisopropyl titanate in a mass ratio of 3.8:1, and mixed and stirred for 1.2h at 215°C to cause a pre-polycondensation reaction, and then the reactor was continuously evacuated until the vacuum degree in the reactor reached 130Pa, and mixed and stirred for 5.2h at 130Pa and 245°C to cause a polycondensation reaction, and branched polyadipate-1,4-butanediol was obtained after the reaction was completed; To the hyperbranched intermediate obtained in step (2), branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol are added, wherein the mass ratio of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is 100:3.8:28:0.28, and the mixture is mixed and stirred at 88° C. for 2.2 h to cause a capping reaction. After the reaction, an intermediate product is obtained. The intermediate product is cooled to 48° C., and then a dimethylethanolamine solution with a concentration of 0.28 mol / L is added to the intermediate product under stirring at a speed of 2800 r / min for emulsification. The mass ratio of the intermediate product to the dimethylethanolamine in the dimethylethanolamine solution is 1:0.095. The hyperbranched polyurethane associative rheology modifier is obtained after high-speed stirring for 1.2 h.

[0091] Example 5 This embodiment provides a method for preparing a hyperbranched polyurethane associative rheology modifier, such as Figure 1 As shown, the preparation method comprises: Step (1), adding polyethylene glycol 6000 into a reaction kettle, heating the polyethylene glycol 6000 to 70° C. until the polyethylene glycol 6000 becomes liquid, then continuing to heat the liquid polyethylene glycol 6000 to 120° C., and evacuating the reaction kettle until the vacuum degree in the reaction kettle reaches 0.08 MPa, and maintaining the vacuum for 3 hours to complete the dehydration treatment; nitrogen was introduced into the reaction kettle, and in the nitrogen atmosphere, isophorone diisocyanate was added to the dehydrated polyethylene glycol 6000, the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate was 1:2.3, and the mixture was mixed and stirred at 90° C. for 2 h to obtain a reaction solution; Add 1,4-butanediol, polyethylene glycol 6000 and isophorone diisocyanate to the reaction solution in a ratio of 1:0.05, and mix and stir at 80° C. for 4 hours to obtain a first precursor solution; Add triethanolamine to the first precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to triethanolamine is 1:0.15, mix and stir at 60° C. for 4 hours to obtain a second precursor solution; N,N-dimethylformamide was added to the second precursor solution to adjust the viscosity of the second precursor solution to 100 mPa·s, and then dibutyltin dilaurate was added to the second precursor solution, the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of dibutyltin dilaurate was 100:0.04, and the mixture was mixed and stirred at 70° C. for 4 hours to obtain a prepolymer terminated by an isocyanate group; Step (2), under a nitrogen atmosphere, trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed, wherein the molar ratio of trimethylolpropane to 2,2-dimethylolpropionic acid is 1:3.2, and the mass ratio of p-toluenesulfonic acid to 2,2-dimethylolpropionic acid is 0.012:1, and the mixture is stirred at 150° C. to react, and when the acid value of the reaction product reaches 20 mgKOH / g, the reaction is stopped to obtain a polyol intermediate; Mixing a polyol intermediate, 2,2-dimethylol propionic acid and p-toluenesulfonic acid, wherein the molar ratio of the polyol intermediate to the 2,2-dimethylol propionic acid is 1:6.2, and the mass ratio of the p-toluenesulfonic acid to the 2,2-dimethylol propionic acid is 0.012:1, stirring and mixing at 150° C. to react, and stopping the reaction when the acid value of the reaction product reaches 20 mgKOH / g to obtain a hyperbranched polyol; Adding a hyperbranched polyol, 1,4-butanediol and acetone to the prepolymer obtained in step (1), wherein the mass ratio of the prepolymer, the hyperbranched polyol, the 1,4-butanediol and the acetone is 100:12:0.8:20, and mixing and stirring at 90° C. for 1 hour to cause a branching reaction, and obtaining a hyperbranched intermediate after the reaction is completed; Step (3), adding adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid into a reaction kettle, wherein the molar ratio of adipic acid to 1,4-butanediol is 1:1.3, the mass ratio of trimethylolphosphine oxide to 1,4-butanediol is 0.035:1, and the mass ratio of the total mass of adipic acid and 1,4-butanediol to the mass of p-toluenesulfonic acid is 100:0.05, introducing nitrogen into the reaction kettle, mixing and stirring adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid under a nitrogen atmosphere at 180° C. and heating to cause an esterification reaction, and when the acid value of the reaction product reaches 10 mgKOH / g, the esterification reaction is terminated to obtain an esterified product; Subsequently, the reactor was evacuated until the vacuum degree in the reactor reached 800Pa, a composite catalyst was added to the esterification product, the total mass ratio of adipic acid and 1,4-butanediol to the mass ratio of the composite catalyst was 100:0.02, the composite catalyst was composed of tetrabutyl titanate and tetraisopropyl titanate in a mass ratio of 4:1, mixed and stirred at 220°C for 1h to cause a pre-polycondensation reaction, and then the reactor was continuously evacuated until the vacuum degree in the reactor reached 150Pa, and mixed and stirred at 150Pa and 250°C for 5h to cause a polycondensation reaction, and branched polyadipate-1,4-butanediol was obtained after the reaction was completed; To the hyperbranched intermediate obtained in step (2), branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol are added, wherein the mass ratio of the hyperbranched intermediate, the branched poly(1,4-butylene adipate), the pentaerythritol triacrylate and the p-methoxyphenol is 100:4:30:0.3, and the mixture is mixed and stirred at 90° C. for 2 h to cause a capping reaction. After the reaction, an intermediate product is obtained. The intermediate product is cooled to 50° C., and then a diethylamine solution with a concentration of 0.3 mol / L is added to the intermediate product under stirring at a speed of 3000 r / min for emulsification. The mass ratio of the intermediate product to the diethylamine in the diethylamine solution is 1:0.1. After high-speed stirring for 1 h, the hyperbranched polyurethane associative rheology modifier is obtained.

[0092] Comparative Example 1 This comparative example provides a method for preparing a hyperbranched polyurethane associative rheology modifier, which differs from Example 1 in that in step (1), the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate is adjusted to 1:1.5, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0093] Comparative Example 2 This comparative example provides a method for preparing a hyperbranched polyurethane associative rheology modifier, which differs from Example 1 in that in step (1), the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate is adjusted to 1:2.5, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0094] Comparative Example 3 This comparative example provides a method for preparing a hyperbranched polyurethane associative rheology modifier, which differs from Example 1 in that, in step (1), the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of 1,4-butanediol is adjusted to 1:0.03, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0095] Comparative Example 4 This comparative example provides a method for preparing a hyperbranched polyurethane associative rheology modifier, which differs from Example 1 in that, in step (1), the mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of 1,4-butanediol is adjusted to 1:0.06, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0096] Comparative Example 5 This comparative example provides a method for preparing a hyperbranched polyurethane associative rheology modifier, which differs from Example 1 in that in step (2), the mass ratio of the prepolymer, the hyperbranched polyol, 1,4-butanediol and acetone is adjusted to 100:5:0.7:15, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0097] Comparative Example 6 This comparative example provides a method for preparing a hyperbranched polyurethane associative rheology modifier, which differs from Example 1 in that in step (2), the mass ratio of the prepolymer, the hyperbranched polyol, 1,4-butanediol and acetone is adjusted to 100:15:0.7:15, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0098] Comparative Example 7 This comparative example provides a method for preparing a hyperbranched polyurethane associative rheology modifier, which differs from Example 1 in that, in step (3), the mass ratio of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is adjusted to 100:3:15:0.2, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0099] Comparative Example 8 This comparative example provides a method for preparing a hyperbranched polyurethane associative rheology modifier, which differs from Example 1 in that, in step (3), the mass ratio of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is adjusted to 100:3:35:0.2, and the other process parameters and operating steps are exactly the same as those in Example 1.

[0100] Comparative Example 9 This comparative example is a commercially available rheology modifier, model BYK-410.

[0101] Application Examples This application example provides a water-based coating, which includes the following components in parts by weight: 85 parts of polyurethane emulsion; 6 parts of deionized water; Defoaming agent (BYK-024) 1 part; 1 part of rheology modifier; Film-forming aid (dipropylene glycol butyl ether) 7 parts.

[0102] According to the above formula, a water-based coating was prepared with a hyperbranched polyurethane associative rheology modifier provided in Example 1, and the water-based coating was applied to the surface of the wood using an applicator. After drying, the surface and cross-sectional morphology of the obtained coating were observed using a scanning electron microscope, and the following was obtained: Figure 7 and Figure 8 As shown in the scanning electron microscope image, it can be seen that there are no obvious holes and defects on the coating surface, and there are no obvious cracks and pores inside the coating after brittle fracture. Combining the surface electron microscope image and the cross-sectional electron microscope image, it can be seen that adding the rheology modifier prepared by the present invention to the water-based coating can also improve the mechanical properties of the coating to a certain extent.

[0103] According to the above formula, the water-based coating was prepared with the rheology modifier provided in Example 1 and Comparative Example 9, and the viscosity of the water-based coating at different rotation speeds was tested. The test temperature was 25±1°C, and the viscosity of the water-based coating at different rotation speeds was summarized and plotted. Figure 6 As shown in the speed-viscosity change curve, it can be seen from the figure that the rheology modifier prepared in Example 1 is added to the water-based coating prepared in Example 1. At low speed, the rheology modifier can form a stable three-dimensional association network structure with the emulsion particles through multi-point association, which significantly improves the viscosity of the emulsion system. As the speed increases, the shear force on the association network structure increases, disassociation occurs, the viscosity of the emulsion system decreases, and shear thinning occurs, which shows that the rheology modifier prepared by the present invention has excellent rheological properties. The commercially available BYK-410 is added to the water-based coating prepared in Comparative Example 9. At low speed, the viscosity of Comparative Example 9 is much lower than that of Example 1, and the viscosity change of the water-based coating prepared in Comparative Example 9 at low and high speeds is not as large as that of Example 1.

[0104] The rheological properties of the rheology modifiers provided in Examples 1 to 5 and Comparative Examples 1 to 9 were tested, and the specific test steps are as follows: The rheology modifiers provided in Examples 1 to 5 and Comparative Examples 1 to 9 were prepared according to the formula of the application example to obtain a water-based coating. The viscosity of the water-based coating at a speed of 6 r / min and 60 r / min was measured using an SNB-2 rotary viscometer under a constant temperature water bath condition of 25±1°C. The thixotropic index was calculated according to the following formula: ; Wherein, TI is the thixotropic index, η1 is the viscosity of the water-based paint at a rotation speed of 60 r / min, and η2 is the viscosity of the water-based paint at a rotation speed of 6 r / min.

[0105] The test results are shown in Table 1.

[0106] Table 1 Rheological properties of the rheology modifiers prepared in Examples 1 to 5 and Comparative Examples 1 to 9

[0107] It can be seen from the data in Table 1 that the rheology modifiers provided in Examples 1 to 5 of the present invention can effectively increase the viscosity of water-based coatings and have excellent thickening ability; at the same time, after adding the rheology modifier prepared by the present invention to the water-based coating, a higher viscosity can be maintained at a low speed and a lower viscosity can be maintained at a high speed, and the coating has excellent rheological properties.

[0108] From the comparison of the test data of Example 1, Comparative Example 1 and Comparative Example 2, it can be seen that the thixotropic index of Comparative Example 1 and Comparative Example 2 is lower than that of Example 1. This is because the amount of isophorone diisocyanate in Comparative Example 1 is too low, and accordingly, the amount of polyethylene glycol 6000 is too high; while the amount of isophorone diisocyanate in Comparative Example 2 is too high, and accordingly, the amount of polyethylene glycol 6000 is too low, thereby affecting the ratio of the hydrophobic segment to the hydrophilic segment in the rheology modifier molecule, ultimately resulting in a decrease in the rheological properties of the rheology modifier.

[0109] From the comparison of the test data of Example 1, Comparative Example 3 and Comparative Example 4, it can be seen that the thixotropic index of Comparative Example 3 and Comparative Example 4 is much lower than that of Example 1. This is because the amount of 1,4-butanediol in Comparative Example 3 is too low, while the amount of 1,4-butanediol in Comparative Example 4 is too high, which affects the ratio of the hydrophobic segment to the hydrophilic segment in the rheology modifier molecule, ultimately resulting in a decrease in the rheological properties of the rheology modifier.

[0110] From the comparison of the test data of Example 1, Comparative Example 5 and Comparative Example 6, it can be seen that the thixotropic index of Comparative Example 5 and Comparative Example 6 is much lower than that of Example 1. This is because the amount of hyperbranched polyol in Comparative Example 5 is too low, while the amount of hyperbranched polyol in Comparative Example 6 is too high, which affects the ratio of hydrophobic segments to hydrophilic segments in the rheology modifier molecules, ultimately resulting in a decrease in the rheological properties of the rheology modifier.

[0111] From the comparison of the test data of Example 1, Comparative Example 7 and Comparative Example 8, it can be seen that the thixotropic index of Comparative Example 7 and Comparative Example 8 is much lower than that of Example 1. This is because the amount of pentaerythritol triacrylate in Comparative Example 7 is too low, while the amount of pentaerythritol triacrylate in Comparative Example 8 is too high, which affects the ratio of the hydrophobic segment to the hydrophilic segment in the rheology modifier molecule, ultimately resulting in a decrease in the rheological properties of the rheology modifier.

[0112] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a hyperbranched polyurethane associative rheology modifier, characterized in that: The preparation method comprises: Step (I), adding polyethylene glycol 6000 into a reaction kettle, dehydrating the polyethylene glycol 6000, adding isophorone diisocyanate to the dehydrated polyethylene glycol 6000 in a nitrogen atmosphere, mixing, stirring and heating to obtain a reaction solution; adding 1,4-butanediol to the reaction solution, mixing, stirring and heating to obtain a first precursor solution; adding triethanolamine to the first precursor solution, mixing, stirring and heating to obtain a second precursor solution; adding dibutyltin dilaurate to the second precursor solution, mixing, stirring and heating to obtain a prepolymer terminated by an isocyanate group; Step (II), under a nitrogen atmosphere, trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed and heated to react to obtain a polyol intermediate; the polyol intermediate, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid are mixed and heated to react to obtain a hyperbranched polyol; the hyperbranched polyol, 1,4-butanediol and acetone are added to the prepolymer obtained in step (I), the mixture is stirred and heated to cause a branching reaction, and a hyperbranched intermediate is obtained after the reaction is completed; Step (III), adding branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol to the hyperbranched intermediate obtained in step (II), stirring and heating to cause a capping reaction, obtaining an intermediate product after the reaction is completed, cooling the intermediate product, and then adding a neutralizer solution to the intermediate product under high-speed stirring conditions for emulsification to obtain the hyperbranched polyurethane associative rheology modifier.

2. The method for preparing a hyperbranched polyurethane associative rheology modifier according to claim 1, characterized in that: In step (I), the specific operation steps of the dehydration treatment of polyethylene glycol 6000 are as follows: The polyethylene glycol 6000 is heated to a melting temperature until the polyethylene glycol 6000 becomes liquid, and then the liquid polyethylene glycol 6000 is further heated to a dehydration temperature, and the reactor is evacuated until the vacuum degree in the reactor reaches the dehydration pressure, and the dehydration is maintained to complete the dehydration process; The melting temperature of the polyethylene glycol 6000 is 60-70°C; The dehydration temperature of the polyethylene glycol 6000 is 110-120°C; The dehydration pressure in the reactor is 0.08-0.09 MPa; The dehydration treatment time is 3 to 5 hours.

3. The method for preparing a hyperbranched polyurethane associative rheology modifier according to claim 1, characterized in that: In step (I), the molar ratio of polyethylene glycol 6000 to isophorone diisocyanate is 1:(1.8-2.3); The heating temperature of the polyethylene glycol 6000 and isophorone diisocyanate is 80-90° C.; The heating time of the polyethylene glycol 6000 and isophorone diisocyanate is 2 to 3 hours; The mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of 1,4-butanediol is 1:(0.04-0.05); The heating temperature of the reaction solution and 1,4-butanediol is 70-80° C.; The heating time of the reaction solution and 1,4-butanediol is 4 to 5 hours; The mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of triethanolamine is 1:(0.1-0.15); The heating temperature of the first precursor solution and triethanolamine is 50-60° C.; The heating time of the first precursor solution and triethanolamine is 4 to 5 hours; Before adding dibutyltin dilaurate to the second precursor solution, adding an organic solvent to the second precursor solution to adjust the viscosity of the second precursor solution to 90-100 mPa·s; The mass ratio of the total mass of polyethylene glycol 6000 and isophorone diisocyanate to the mass of dibutyltin dilaurate is 100:(0.03-0.04); The heating temperature of the second precursor solution and dibutyltin dilaurate is 60-70° C.; The mixing time of the second precursor solution and dibutyltin dilaurate is 4 to 5 hours.

4. The method for preparing a hyperbranched polyurethane associative rheology modifier according to claim 1, characterized in that: In step (II), when preparing the polyol intermediate, the molar ratio of trimethylolpropane to 2,2-dimethylolpropionic acid is 1:(3-3.2); When preparing the polyol intermediate, the mass ratio of p-toluenesulfonic acid to 2,2-dimethylolpropionic acid is (0.008-0.012):1; The reaction temperature of trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid is 140-150° C.; When the acid value of the reaction product obtained by the reaction of trimethylolpropane, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid is ≤20 mgKOH / g, stopping the reaction to obtain the polyol intermediate; When preparing the hyperbranched polyol, the molar ratio of the polyol intermediate to 2,2-dimethylol propionic acid is 1:(6-6.2); When preparing the hyperbranched polyol, the mass ratio of p-toluenesulfonic acid to 2,2-dimethylolpropionic acid is (0.008-0.012):1; The reaction temperature of the polyol intermediate, 2,2-dimethylol propionic acid and p-toluenesulfonic acid is 140-150° C.; When the acid value of the reaction product obtained by reacting the polyol intermediate, 2,2-dimethylolpropionic acid and p-toluenesulfonic acid is less than or equal to 20 mgKOH / g, the reaction is stopped to obtain the hyperbranched polyol.

5. The method for preparing a hyperbranched polyurethane associative rheology modifier according to claim 1, characterized in that: In step (II), the mass ratio of the prepolymer, hyperbranched polyol, 1,4-butanediol and acetone is 100:(8-12):(0.7-0.8):(15-20); The heating temperature for the branching reaction of the prepolymer, hyperbranched polyol, 1,4-butanediol and acetone is 80-90° C.; The heating time for the branching reaction of the prepolymer, the hyperbranched polyol, 1,4-butanediol and acetone is 1 to 3 hours.

6. The method for preparing a hyperbranched polyurethane associative rheology modifier according to claim 1, characterized in that: In step (III), the branched poly(1,4-butylene adipate) is prepared by the following method: Adipic acid, 1,4-butanediol, trihydroxymethylphosphine oxide and p-toluenesulfonic acid are added to a reactor, nitrogen is introduced into the reactor, and adipic acid, 1,4-butanediol, trihydroxymethylphosphine oxide and p-toluenesulfonic acid are mixed, stirred and heated under a nitrogen atmosphere to cause an esterification reaction to obtain an esterification product; then, the reactor is evacuated until the vacuum degree in the reactor reaches a pre-polycondensation pressure, a composite catalyst is added to the esterification product, mixed, stirred and heated to cause a pre-polycondensation reaction, and then the reactor is continuously evacuated until the vacuum degree in the reactor reaches a polycondensation pressure, and mixed, stirred and heated under the polycondensation pressure to cause a polycondensation reaction, and after the reaction is completed, the branched polyadipate-1,4-butanediol ester is obtained.

7. The method for preparing a hyperbranched polyurethane associative rheology modifier according to claim 6, characterized in that: When preparing branched poly(1,4-butylene adipate), the molar ratio of adipic acid to 1,4-butylene adipate is 1:(1.2-1.3); The mass ratio of trimethylolphosphine oxide to 1,4-butanediol is (0.025-0.035):1; The mass ratio of the total mass of the adipic acid and 1,4-butanediol to the mass of p-toluenesulfonic acid is 100:(0.03-0.05); The temperature of the esterification reaction of adipic acid, 1,4-butanediol, trimethylolphosphine oxide and p-toluenesulfonic acid is 150-180° C.; When the acid value of the reaction product obtained by the esterification reaction is ≤10 mgKOH / g, the esterification reaction is completed to obtain the esterification product; The pre-condensation pressure is 600-800 Pa; The ratio of the total mass of the adipic acid and 1,4-butanediol to the mass of the composite catalyst is 100:(0.01-0.02); The composite catalyst is composed of tetrabutyl titanate and tetraisopropyl titanate, wherein the mass ratio of tetrabutyl titanate to tetraisopropyl titanate is (3-4):1; The heating temperature of the pre-polycondensation reaction is 200-220°C; The heating time of the pre-polycondensation reaction is 1 to 2 hours; The polycondensation pressure is 100-150 Pa; The heating temperature of the polycondensation reaction is 230-250°C; The heating time of the polycondensation reaction is 5 to 6 hours.

8. The method for preparing a hyperbranched polyurethane associative rheology modifier according to claim 1, characterized in that: In step (III), the mass ratio of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is 100:(3-4):(20-30):(0.2-0.3); The heating temperature for the end-capping reaction of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is 80-90° C.; The heating time of the end-capping reaction of the hyperbranched intermediate, branched poly(1,4-butylene adipate), pentaerythritol triacrylate and p-methoxyphenol is 2 to 3 hours; After the end-capping reaction is completed, the intermediate product obtained by the reaction is cooled to 40-50° C.; The neutralizer solution consists of a neutralizer and deionized water; The concentration of the neutralizer in the neutralizer solution is 0.2-0.3 mol / L; The neutralizing agent includes any one of diethylamine, triethylamine, diisopropylethylamine or dimethylethanolamine, or a combination of at least two thereof; The mass ratio of the intermediate product to the neutralizer in the neutralizer solution is 1:(0.08-0.1); The rotation speed of the high-speed stirring is 2000-3000 r / min; The high-speed stirring time is 1 to 2 hours.

9. A hyperbranched polyurethane associative rheology modifier, characterized in that: The hyperbranched polyurethane associative rheology modifier is prepared by the preparation method according to any one of claims 1 to 8.

10. A water-based paint, characterized in that: The water-based coating comprises an emulsion, a film-forming aid, a defoamer, a rheology modifier and deionized water, wherein the rheology modifier is the hyperbranched polyurethane associative rheology modifier according to claim 9.

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