A thixotropic agent composition, its preparation method and use

Abstract

The application belongs to the technical field of thixotropic agents, and specifically discloses a thixotropic agent composition, a preparation method and application thereof; the thixotropic agent composition is prepared by using modified microcrystalline cellulose, mica powder and micro-powdered polyamide wax as the thixotropic agent composition in a mass ratio of 1: (0.8-1.5): (0.6-1). The organic silicon grafted modified microcrystalline cellulose has a fiber structure and can quickly form a three-dimensional fiber network structure throughout the system to provide basic structural support for the system. The mica powder is a sheet-shaped inorganic powder, so that the system can remain stable in a static state and is not prone to delamination, sedimentation and sagging. The micro-powdered polyamide wax forms a large number of hydrogen bond nodes and physical association points in the system, and the thixotropic agent composition can effectively improve the thixotropy index, storage stability and freeze-thaw stability of the coating.

Description

Technical Field

[0001] This invention relates to the field of thixotropic agents, specifically to a thixotropic agent composition, its preparation method, and its application. Background Technology

[0002] Thixotropic agents are core functional additives in coating systems that regulate rheological behavior and improve storage and application performance. Their role is to enable coatings to exhibit typical thixotropic properties such as shear thinning and static gelation, thereby effectively inhibiting pigment and filler sedimentation, preventing sagging during application, and reducing stratification and water separation during storage. They play an irreplaceable role in ensuring coating stability, film uniformity, and application safety.

[0003] Currently, thixotropic agents used in the coatings industry are mainly divided into three categories: inorganic thixotropic agents and organic polymeric thixotropic agents. Inorganic thixotropic agents, such as bentonite, mica, and fumed silica, are widely available and inexpensive, but generally have poor compatibility with organic resins, emulsions, and wax components. They tend to agglomerate and are difficult to disperse in aqueous systems, making it difficult to form a stable and uniform rheological network. Furthermore, their thixotropic enhancement is limited when used alone. Organic polymeric thixotropic agents, such as cellulose ethers, while possessing certain thickening and structural support properties, are prone to swelling, flocculation, and coarsening in coating systems with medium to high pigment content, high solids content, or containing organic components due to their strong surface polarity and excessive hydrophilicity. This not only results in low thixotropic efficiency but also affects the storage stability and film-forming properties of the coating.

[0004] Therefore, this application is submitted. Summary of the Invention

[0005] This invention provides a thixotropic agent composition, its preparation method, and its application. The thixotropic agent composition described in this application has excellent thixotropic properties and can effectively improve the thixotropic index, storage stability, and freeze-thaw stability of coatings.

[0006] The present invention solves its technical problem by adopting the following technical solution: A thixotropic composition comprising modified microcrystalline cellulose, mica powder, and micronized polyamide wax; wherein the mass ratio of the modified microcrystalline cellulose, mica powder, and micronized polyamide wax is 1:(0.8~1.5):(0.6~1).

[0007] As an embodiment of this application, the average aspect ratio of the mica powder is 60~120.

[0008] As an embodiment of this application, the average aspect ratio of the mica powder is 80~100.

[0009] As an embodiment of this application, the method for preparing the modified microcrystalline cellulose is as follows: (1) Mix glycerol and water evenly, then add micronized rice bran wax and stir evenly, then add microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride, stir at 50~70℃ for 0.2~2h, filter, dry to obtain pretreated microcrystalline cellulose; (2) Add hydrogen-containing silicone oil and 1,4-butenediol to isopropanol, then add pretreated microcrystalline cellulose and catalyst, react at 60~90℃ for 2~5h, filter, dry, and obtain modified microcrystalline cellulose.

[0010] As an embodiment of this application, the mass ratio of glycerol, water, micronized rice bran wax, microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride is (0.2~0.3):(4~10):(0.04~0.06):1:(0.02~0.04):(0.01~0.02).

[0011] As an embodiment of this application, the mass ratio of the hydrogen-containing silicone oil, 1,4-butenediol, isopropanol, pretreated microcrystalline cellulose, and catalyst is (0.1~0.15):(0.08~0.12):(4~10):1:(0.01~0.02).

[0012] As an embodiment of this application, the hydrogen content of the hydrogen-containing silicone oil is 0.5~0.82wt%.

[0013] As an embodiment of this application, the melting point of the micronized rice bran wax is 78~80℃, and the acid value is 50~90mg KOH / g; The average particle size of the microcrystalline cellulose is 5~20μm.

[0014] This application also provides a method for preparing a thixotropic agent composition, comprising the following steps: mixing modified microcrystalline cellulose, mica powder and micronized polyamide wax evenly to obtain a thixotropic agent composition.

[0015] This application also provides the use of a thixotropic composition in the preparation of coatings or sealants.

[0016] The beneficial effects of this invention are as follows: This application uses a modified microcrystalline cellulose, mica powder, and micronized polyamide wax in a mass ratio of 1:(0.8~1.5):(0.6~1) as a thixotropic agent composition. The organosilicon-grafted modified microcrystalline cellulose has a fibrous structure, which can quickly form a three-dimensional fibrous network structure throughout the entire system, providing basic structural support for the system, improving the structural strength and thixotropic recovery ability of the system, and enabling the system to quickly recover its viscosity and gel state after standing. The mica powder is a flake-shaped inorganic powder, and mica powder with a suitable aspect ratio can be uniformly embedded in the three-dimensional network of modified microcrystalline cellulose, significantly improving the system's anti-settling and anti-sagging properties, making the system stable in a static state and less prone to stratification, sedimentation, and sagging. The micronized polyamide wax forms a large number of hydrogen bond nodes and physical association points in the system, and the thixotropic agent composition can effectively improve the thixotropic index, storage stability, and freeze-thaw stability of the coating. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] In this invention, the technical features described in an open-ended manner include both closed-ended technical solutions composed of the listed features and open-ended technical solutions that include the listed features.

[0019] In this invention, numerical ranges are involved. Unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe features or characteristics, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0020] In this invention, there are no particular limitations on the specific dispersion and stirring methods.

[0021] Unless otherwise specified, all reagents or instruments used in this invention are commercially available conventional products. Unless otherwise specified, the raw materials used in each comparative example and the parallel experiments of each embodiment are the same commercially available products.

[0022] The raw material sources for the examples and comparative examples are as follows: Mica-1: with an average diameter-to-thickness ratio of 80, grade Y-3000, derived from Yamaguchi mica.

[0023] Mica-2: with an average diameter-to-thickness ratio of 100, grade NCF-322, derived from Yamaguchi mica.

[0024] Mica-3: with an average diameter-to-thickness ratio of 60, grade CFA-50, derived from Yamaguchi mica.

[0025] Mica-4: Average diameter-to-thickness ratio is 120, grade TM-20, derived from Yamaguchi mica.

[0026] Micronized polyamide wax: brand name Crayvallac ULTRA, sourced from Arkema.

[0027] Microcrystalline cellulose: with an average particle size of 12μm, brand name CS Sensory 12, sourced from JRS in Germany.

[0028] Micronized rice bran wax: melting point 78~80℃, acid value 50~60mg KOH / g, brand name Bio-M803, sourced from Chongqing Hecai Chemical.

[0029] Hydrogen-containing silicone oil: hydrogen content is 0.5~0.59wt%, grade V202-050, sourced from Foshan Huagu Organosilicon.

[0030] Catalyst: Platinum catalyst, grade PT1000-5000, sourced from Shenzhen Xinyongsheng New Materials.

[0031] This application provides a thixotropic composition comprising modified microcrystalline cellulose, mica powder, and micronized polyamide wax; wherein the mass ratio of the modified microcrystalline cellulose, mica powder, and micronized polyamide wax is 1:(0.8~1.5):(0.6~1).

[0032] This application uses a thixotropic agent composition of modified microcrystalline cellulose, mica powder, and micronized polyamide wax in a mass ratio of 1:(0.8~1.5):(0.6~1). The organosilicon-grafted modified microcrystalline cellulose has a fibrous structure, which can quickly form a three-dimensional fibrous network structure throughout the entire system, providing basic structural support for the system, improving the structural strength and thixotropic recovery ability of the system, and enabling the system to quickly recover its viscosity and gel state after standing. The mica powder is a flake-shaped inorganic powder. Mica powder with a suitable aspect ratio can be uniformly embedded in the three-dimensional network of modified microcrystalline cellulose, significantly improving the system's anti-settling and anti-sagging properties, making the system stable in a static state and less prone to stratification, sedimentation, and sagging. The micronized polyamide wax forms a large number of hydrogen bond nodes and physical association points in the system; the thixotropic agent composition can effectively improve the thixotropic index, storage stability, and freeze-thaw stability of the coating.

[0033] This application significantly improves the thixotropic properties of a thixotropic agent composition through the synergistic effect of modified microcrystalline cellulose, mica powder, and micronized polyamide wax. The modified microcrystalline cellulose provides a three-dimensional continuous skeleton, the mica powder provides lamellar physical reinforcement, and the wax-based thixotropic agent provides reversible hydrogen bond thixotropic nodes. The three components work together, promote each other, and reinforce each other, resulting in a higher thixotropic index, more stable storage, and superior anti-settling and anti-sagging properties of the system.

[0034] In some embodiments, the average aspect ratio of the mica powder is 60 to 120, for example, it can be a range consisting of 60, 70, 80, 90, 100, 110, 120 or any two of these values.

[0035] In some embodiments, the average aspect ratio of the mica powder is 80 to 100. By controlling the average aspect ratio of the mica powder within this range, it is easier to form a uniform and continuous lamellar physical network in the system. This allows it to more effectively synergize with the three-dimensional fibrous skeleton of modified microcrystalline cellulose and the hydrogen bond nodes of wax-based thixotropic agents, significantly improving the thixotropic index of the system.

[0036] In some embodiments, the average particle size of the mica powder is 10~50μm, for example, it can be 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm or any two of these values.

[0037] In some embodiments, the Dv10 particle size of the micronized polyamide wax is 0.5~5μm, for example, it can be 0.5μm, 1μm, 2μm, 3μm, 4μm, 5μm or any two of these values.

[0038] In some embodiments, the Dv90 particle size of the micronized polyamide wax is 8~50μm, for example, it can be 8μm, 10μm, 12μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 50μm or any two of these values.

[0039] In some embodiments, the melting point of the micronized polyamide wax is 118~140°C, for example, it can be 118°C, 120°C, 122°C, 125°C, 130°C, 135°C, 140°C or any two of these values.

[0040] In some embodiments, the bulk density of the micronized polyamide wax is 0.4~0.6 g / cm³. 3 For example, it could be 0.4 g / cm³. 3 0.42g / cm 3 0.45g / cm3 0.48g / cm 3 0.5g / cm 3 0.52g / cm 3 0.55g / cm 3 0.6g / cm 3 Or the range formed by any two of these values.

[0041] In some embodiments, the modified microcrystalline cellulose is prepared by: (1) Mix glycerol and water evenly, then add micronized rice bran wax and stir evenly, then add microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride, stir at 50~70℃ for 0.2~2h, filter, dry to obtain pretreated microcrystalline cellulose; (2) Add hydrogen-containing silicone oil and 1,4-butenediol to isopropanol, then add pretreated microcrystalline cellulose and catalyst, react at 60~90℃ for 2~5h, filter, dry, and obtain modified microcrystalline cellulose.

[0042] This application pretreats microcrystalline cellulose with micronized rice bran wax, citric acid, and hexadecyltrimethylammonium chloride, and then modifies it with the reaction product of hydrosilicone oil and 1,4-butenediol. This introduces hydrophobic siloxane segments onto the surface of the microcrystalline cellulose, significantly reducing its surface energy and preventing problems such as agglomeration, swelling, and thixotropic failure caused by excessive water absorption in coating systems. It exhibits good compatibility and uniform miscibility with micronized polyamide wax, forming a stable and uniform thixotropic network, avoiding defects such as wax precipitation, layering, white spots, and a grainy texture. Simultaneously, the modified microcrystalline cellulose can better form hydrogen bonds and physical entanglements with mica powder, resulting in a stronger interfacial bond between the fibrous and sheet phases. The overall three-dimensional network is more stable, more shear-resistant, and less prone to damage, maintaining excellent thixotropic properties even after long-term storage.

[0043] In some embodiments, the mass ratio of glycerol, water, micronized rice bran wax, microcrystalline cellulose, citric acid, and hexadecyltrimethylammonium chloride is (0.2~0.3):(4~10):(0.04~0.06):1:(0.02~0.04):(0.01~0.02).

[0044] In some embodiments, the mass ratio of the hydrogen-containing silicone oil, 1,4-butenediol, isopropanol, pretreated microcrystalline cellulose, and catalyst is (0.1~0.15):(0.08~0.12):(4~10):1:(0.01~0.02).

[0045] In some embodiments, the hydrogen content of the hydrogen-containing silicone oil is 0.5~0.82wt%, for example, it can be 0.5wt%, 0.52wt%, 0.55wt%, 0.58wt%, 0.6wt%, 0.62wt%, 0.65wt%, 0.68wt%, 0.7wt%, 0.72wt%, 0.75wt%, 0.78wt%, 0.8wt%, 0.82wt%, or any two of these values.

[0046] In some embodiments, the melting point of the micronized rice bran wax is 78-80°C, for example, it can be 78°C, 78.5°C, 79°C, 79.5°C, 80°C or any two of these values, and the acid value is 50-90 mg KOH / g, for example, it can be 50 mg KOH / g, 55 mg KOH / g, 60 mg KOH / g, 70 mg KOH / g, 80 mg KOH / g, 90 mg KOH / g or any two of these values.

[0047] In some embodiments, the average particle size of the microcrystalline cellulose is 5 to 20 μm, for example, it can be 5 μm, 6 μm, 7 μm, 8 μm, 10 μm, 12 μm, 14 μm, 15 μm, 16 μm, 18 μm, 20 μm or any two of these values.

[0048] In some embodiments, the catalyst is a platinum catalyst.

[0049] This application also provides a method for preparing a thixotropic agent composition, comprising the following steps: mixing modified microcrystalline cellulose, mica powder and micronized polyamide wax evenly to obtain a thixotropic agent composition.

[0050] This application also provides an application of a thixotropic composition in the preparation of coatings or sealants.

[0051] The present application is further illustrated below with specific embodiments:

[0052] Example 1 A thixotropic agent composition comprising modified microcrystalline cellulose, mica powder-1, and micronized polyamide wax; wherein the mass ratio of the modified microcrystalline cellulose, mica powder-1, and micronized polyamide wax is 1:1.2:0.8.

[0053] The method for preparing the modified microcrystalline cellulose is as follows: (1) Glycerin and water are mixed evenly at 50°C, then micronized rice bran wax is added, and the mixture is stirred at 100 rpm for 5 min at 75°C. Then microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride are added, and the mixture is stirred at 65°C for 1 h. The mixture is filtered and dried to obtain pretreated microcrystalline cellulose. The mass ratio of glycerin, water, micronized rice bran wax, microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride is 0.2:4:0.04:1:0.02:0.01.

[0054] (2) Hydrogen-containing silicone oil and 1,4-butenediol were added to isopropanol, followed by pretreated microcrystalline cellulose and catalyst. The mixture was reacted at 85°C for 4 hours, filtered, and dried to obtain modified microcrystalline cellulose. The mass ratio of the hydrogen-containing silicone oil, 1,4-butenediol, isopropanol, pretreated microcrystalline cellulose, and catalyst was 0.15:0.12:10:1:0.02.

[0055] The method for preparing the thixotropic agent composition includes the following steps: mixing modified microcrystalline cellulose, mica powder and micronized polyamide wax at 200 rpm for 5 min, and then mixing at 600 rpm for 10 min to obtain the thixotropic agent composition.

[0056] Example 2 A thixotropic agent composition comprising modified microcrystalline cellulose, mica powder-1, and micronized polyamide wax; wherein the mass ratio of the modified microcrystalline cellulose, mica powder-1, and micronized polyamide wax is 1:1.5:1.

[0057] The method for preparing the modified microcrystalline cellulose is as follows: (1) Glycerin and water are mixed evenly at 50°C, then micronized rice bran wax is added, and the mixture is stirred at 100 rpm for 5 min at 75°C. Then microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride are added, and the mixture is stirred at 65°C for 1 h. The mixture is filtered and dried to obtain pretreated microcrystalline cellulose. The mass ratio of glycerin, water, micronized rice bran wax, microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride is 0.2:4:0.04:1:0.02:0.01.

[0058] (2) Hydrogen-containing silicone oil and 1,4-butenediol were added to isopropanol, followed by pretreated microcrystalline cellulose and catalyst. The mixture was reacted at 85°C for 4 hours, filtered, and dried to obtain modified microcrystalline cellulose. The mass ratio of the hydrogen-containing silicone oil, 1,4-butenediol, isopropanol, pretreated microcrystalline cellulose, and catalyst was 0.15:0.12:10:1:0.02.

[0059] The method for preparing the thixotropic agent composition includes the following steps: mixing modified microcrystalline cellulose, mica powder and micronized polyamide wax at 200 rpm for 5 min, and then mixing at 600 rpm for 10 min to obtain the thixotropic agent composition.

[0060] Example 3 A thixotropic composition comprising modified microcrystalline cellulose, mica powder-1, and micronized polyamide wax; wherein the mass ratio of the modified microcrystalline cellulose, mica powder-1, and micronized polyamide wax is 1:0.8:0.6.

[0061] The method for preparing the modified microcrystalline cellulose is as follows: (1) Glycerin and water are mixed evenly at 50°C, then micronized rice bran wax is added, and the mixture is stirred at 100 rpm for 5 min at 75°C. Then microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride are added, and the mixture is stirred at 65°C for 1 h. The mixture is filtered and dried to obtain pretreated microcrystalline cellulose. The mass ratio of glycerin, water, micronized rice bran wax, microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride is 0.2:4:0.04:1:0.02:0.01.

[0062] (2) Hydrogen-containing silicone oil and 1,4-butenediol were added to isopropanol, followed by pretreated microcrystalline cellulose and catalyst. The mixture was reacted at 85°C for 4 hours, filtered, and dried to obtain modified microcrystalline cellulose. The mass ratio of the hydrogen-containing silicone oil, 1,4-butenediol, isopropanol, pretreated microcrystalline cellulose, and catalyst was 0.15:0.12:10:1:0.02.

[0063] The method for preparing the thixotropic agent composition includes the following steps: mixing modified microcrystalline cellulose, mica powder and micronized polyamide wax at 200 rpm for 5 min, and then mixing at 600 rpm for 10 min to obtain the thixotropic agent composition.

[0064] Example 4 A thixotropic agent composition comprising modified microcrystalline cellulose, mica powder-1, and micronized polyamide wax; wherein the mass ratio of the modified microcrystalline cellulose, mica powder-1, and micronized polyamide wax is 1:1.2:0.8.

[0065] The method for preparing the modified microcrystalline cellulose is as follows: (1) Glycerin and water are mixed evenly at 50°C, then micronized rice bran wax is added, and the mixture is stirred at 100 rpm for 5 min at 75°C. Then microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride are added, and the mixture is stirred at 65°C for 1 h. The mixture is filtered and dried to obtain pretreated microcrystalline cellulose. The mass ratio of glycerin, water, micronized rice bran wax, microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride is 0.3:10:0.06:1:0.04:0.02.

[0066] (2) Hydrogen-containing silicone oil and 1,4-butenediol were added to isopropanol, followed by pretreated microcrystalline cellulose and catalyst. The mixture was reacted at 85°C for 4 hours, filtered, and dried to obtain modified microcrystalline cellulose. The mass ratio of the hydrogen-containing silicone oil, 1,4-butenediol, isopropanol, pretreated microcrystalline cellulose, and catalyst was 0.1:0.08:4:1:0.01.

[0067] The method for preparing the thixotropic agent composition includes the following steps: mixing modified microcrystalline cellulose, mica powder and micronized polyamide wax at 200 rpm for 5 min, and then mixing at 600 rpm for 10 min to obtain the thixotropic agent composition.

[0068] Example 5 Example 5 differs from Example 1 in that an equal amount of mica powder-2 is used to replace mica powder-1, while all other aspects remain the same.

[0069] Example 6 Example 6 differs from Example 1 in that an equal amount of mica powder-3 is used to replace mica powder-1, while all other aspects remain the same.

[0070] Example 7 Example 7 differs from Example 1 in that an equal amount of mica powder-4 is used to replace mica powder-1, while all other aspects remain the same.

[0071] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the mass ratio of modified microcrystalline cellulose, mica powder, and micronized polyamide wax is different, while all other aspects are the same.

[0072] In this comparative example, the mass ratio of modified microcrystalline cellulose, mica powder, and micronized polyamide wax was 1:2:2.

[0073] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the mass ratio of modified microcrystalline cellulose, mica powder and micronized polyamide wax is different, while all other aspects are the same.

[0074] In this comparative example, the mass ratio of modified microcrystalline cellulose, mica powder, and micronized polyamide wax was 1:0.25:0.25.

[0075] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that Comparative Example 3 does not contain modified microcrystalline cellulose, but they are otherwise the same.

[0076] A thixotropic composition comprising mica powder-1 and micronized polyamide wax; wherein the mass ratio of mica powder-1 to micronized polyamide wax is 1.2:0.8.

[0077] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that Comparative Example 4 does not contain mica powder-1, but all other aspects are the same.

[0078] A thixotropic composition comprising modified microcrystalline cellulose and micronized polyamide wax; wherein the mass ratio of the modified microcrystalline cellulose to the micronized polyamide wax is 1:0.8.

[0079] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that Comparative Example 5 does not contain micronized polyamide wax, but they are otherwise the same.

[0080] A thixotropic agent composition comprising modified microcrystalline cellulose and mica powder-1; wherein the mass ratio of the modified microcrystalline cellulose to mica powder-1 is 1:1.2.

[0081] Comparative Example 6 The difference between Comparative Example 6 and Example 1 is that the same amount of microcrystalline cellulose and other modified microcrystalline cellulose were used.

[0082] A thixotropic composition comprising microcrystalline cellulose, mica powder-1, and micronized polyamide wax; wherein the mass ratio of the microcrystalline cellulose, mica powder-1, and micronized polyamide wax is 1:1.2:0.8.

[0083] Comparative Example 7 The difference between Comparative Example 7 and Example 1 is that the preparation method of the modified microcrystalline cellulose is different, but everything else is the same.

[0084] The method for preparing the modified microcrystalline cellulose is as follows: (1) Glycerin and water are mixed evenly at 50°C, then micronized rice bran wax is added, and the mixture is stirred at 100 rpm for 5 min at 75°C. Then microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride are added, and the mixture is stirred at 65°C for 1 h. The mixture is filtered and dried to obtain modified microcrystalline cellulose. The mass ratio of glycerin, water, micronized rice bran wax, microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride is 0.2:4:0.04:1:0.02:0.01.

[0085] Comparative Example 8 The difference between Comparative Example 8 and Example 1 is that the preparation method of the modified microcrystalline cellulose is different, but everything else is the same.

[0086] The method for preparing the modified microcrystalline cellulose is as follows: (1) Hydrogen-containing silicone oil and 1,4-butenediol were added to isopropanol, followed by microcrystalline cellulose and a catalyst. The mixture was reacted at 85°C for 4 hours, filtered, and dried to obtain modified microcrystalline cellulose. The mass ratio of the hydrogen-containing silicone oil, 1,4-butenediol, isopropanol, microcrystalline cellulose, and catalyst was 0.15:0.12:10:1:0.02.

[0087] Test case Weigh the raw materials according to the following mass percentage formula: 8% titanium dioxide, 6% ethylene glycol, 1% film-forming aid (alcohol ester-12), 0.3% defoamer (TEGO® Foamex 840), 1.2% thixotropic agent composition, 15% water, and the balance acrylic emulsion (MT-3612).

[0088] Water, ethylene glycol, and defoamer are added to a dispersion tank and stirred until homogeneous. Then titanium dioxide is added and stirred until homogeneous. Finally, the remaining substances are added and stirred until homogeneous to obtain the test coating.

[0089] 1. The viscosity p1 of the sample was measured at 0.6 rpm and 6 rpm at 25°C using a rotational viscometer. The ratio of p1 to p2 is recorded as the thixotropic index.

[0090] 2. Place the coating at 25℃ for 180 days and observe its stability.

[0091] 3. Freeze-thaw stability: Place the coating in a sealed container, seal it, and place it at -5℃ for 16 hours. Then thaw it at 25℃ for 6 hours. This is one cycle. After 7 cycles, open the container and check the state of the sample. If it can be stirred evenly, it passes the test.

[0092] Table 1

[0093] As can be seen from Table 1, the thixotropic agent composition described in this application has excellent thixotropic properties and can effectively improve the thixotropic index, storage stability and freeze-thaw stability of the coating.

[0094] Finally, it should be noted that the above embodiments are used to illustrate the technical solutions of the present invention and not to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A thixotropic agent composition, characterized in that, It includes modified microcrystalline cellulose, mica powder and micronized polyamide wax; the mass ratio of the modified microcrystalline cellulose, mica powder and micronized polyamide wax is 1:(0.8~1.5):(0.6~1).

2. The thixotropic composition according to claim 1, characterized in that, The average aspect ratio of the mica powder is 60~120.

3. The thixotropic composition according to claim 2, characterized in that, The average aspect ratio of the mica powder is 80~100.

4. The thixotropic composition according to claim 1, characterized in that, The method for preparing the modified microcrystalline cellulose is as follows: (1) Mix glycerol and water evenly, then add micronized rice bran wax and stir evenly, then add microcrystalline cellulose, citric acid and hexadecyltrimethylammonium chloride, stir at 50~70℃ for 0.2~2h, filter, dry to obtain pretreated microcrystalline cellulose; (2) Add hydrogen-containing silicone oil and 1,4-butenediol to isopropanol, then add pretreated microcrystalline cellulose and catalyst, react at 60~90℃ for 2~5h, filter, dry, and obtain modified microcrystalline cellulose.

5. The thixotropic composition according to claim 4, characterized in that, The mass ratio of glycerol, water, micronized rice bran wax, microcrystalline cellulose, citric acid, and hexadecyltrimethylammonium chloride is (0.2~0.3):(4~10):(0.04~0.06):1:(0.02~0.04):(0.01~0.02).

6. The thixotropic composition according to claim 4, characterized in that, The mass ratio of the hydrogen-containing silicone oil, 1,4-butenediol, isopropanol, pretreated microcrystalline cellulose, and catalyst is (0.1~0.15):(0.08~0.12):(4~10):1:(0.01~0.02).

7. The thixotropic composition according to claim 4, characterized in that, The hydrogen content of the hydrogen-containing silicone oil is 0.5~0.82wt%.

8. The thixotropic composition according to claim 4, characterized in that, The melting point of the micronized rice bran wax is 78~80℃, and the acid value is 50~90mg KOH / g; The average particle size of the microcrystalline cellulose is 5~20μm.

9. A method for preparing the thixotropic composition according to any one of claims 1 to 1, characterized in that, Includes the following steps: Modified microcrystalline cellulose, mica powder, and micronized polyamide wax are mixed evenly to obtain a thixotropic agent composition.

10. The use of the thixotropic composition according to any one of claims 1 to 8 in the preparation of coatings or sealants.

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