A production process of wear-resistant polyurethane coating

Abstract

The application relates to the technical field of high polymer coating and discloses a production process of wear-resistant polyurethane coating, which comprises the following raw materials: isophorone diisocyanate, polytetrahydrofuran ether diol, organic tin catalyst, multifunctional rubber, modified filler, small-molecule chain extender, triethylamine and deionized water; the multifunctional rubber and the modified filler are prepared and involved in the preparation process of the polyurethane coating, so that the prepared polyurethane coating has excellent wear resistance and antibacterial effect, also has corrosion resistance, can stably exist in a corrosive medium, effectively meets the use demand of the coating in various environments, greatly expands the use field of the polyurethane coating, and prolongs the service life of the coating.

Description

Technical Field

[0001] This invention relates to the field of polymer coatings technology, specifically to a production process for a wear-resistant polyurethane coating. Background Technology

[0002] Polyurethane coatings are a versatile polymer coating material with excellent adhesion and flexibility, playing a crucial role in many fields such as industrial protection, home decoration, and medical devices. They can adapt to diverse application needs. However, as modern industry demands increasingly higher material performance, especially in high-end manufacturing, medical and health, and food processing, the need for multifunctional coatings is growing. Ordinary polyurethane coatings are revealing more and more shortcomings during long-term use. Their wear resistance is insufficient to meet the needs of high-load, high-frequency use scenarios in machinery manufacturing, their corrosion resistance is insufficient to resist the erosion of corrosive media, and their poor antibacterial properties cannot inhibit bacterial growth. Ultimately, they will lose their protective function for the substrate material. Ordinary polyurethane coatings can no longer meet current application needs.

[0003] Patent CN113801558B discloses a corrosion-resistant basalt flake polyurethane coating and its coating method. This corrosion-resistant basalt flake polyurethane coating incorporates iron and nickel powder particles. After coating, a strip magnet is used to directionally move the coating before it cures, thereby causing the basalt flakes to move directionally and translate. Although this achieves the same enhanced anti-corrosion performance using a relatively small amount of basalt flakes, the patent contains a large amount of inorganic small molecules, posing a risk of inorganic molecule aggregation. Furthermore, the patent does not improve the antibacterial effect. Since bacteria are microorganisms, the physical barrier of basalt flakes alone is insufficient to prevent microbial erosion, thus affecting the coating's anti-corrosion capability. Summary of the Invention

[0004] The purpose of this invention is to provide a production process for wear-resistant polyurethane coatings, which solves the following technical problems: (1) ordinary polyurethane coatings have poor wear resistance and corrosion resistance and are easily damaged during use; (2) ordinary polyurethane coatings do not have antibacterial effects, which limits their application areas in actual use.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A manufacturing process for a wear-resistant polyurethane coating includes the following steps:

[0007] Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add organotin catalyst, mix evenly at 25-30℃, heat to 50-55℃ and react for 1-2 hours, then continue heating to 75-85℃ and react for 0.5-1 hours to obtain polyurethane prepolymer.

[0008] Step 2: Add ethylene glycol and multifunctional rubber to the polyurethane prepolymer, heat to 80-85℃ and react for 6-8 hours, then cool to 40-45℃ and add triethylamine and modified filler. After reacting for 2-3 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the wear-resistant polyurethane coating.

[0009] The wear-resistant polyurethane coating comprises the following raw materials in parts by weight: 18-22 parts isophorone diisocyanate, 16-18 parts polytetrahydrofuran ether diol, 1-2 parts organotin catalyst, 8-10 parts multifunctional rubber, 5-6 parts modified filler, 3-5 parts small molecule chain extender, 2-3 parts triethylamine, and 80-100 parts deionized water.

[0010] Furthermore, the organotin catalyst is any one of dibutyltin dilaurate and stannous octoate; the small molecule chain extender is any one of ethylene glycol, 1,4-butanediol, and propylene glycol.

[0011] Furthermore, the preparation method of the multifunctional rubber includes the following steps:

[0012] S1: The carboxyl-terminated liquid nitrile rubber and 2-(trifluoromethyl)ethylene oxide were placed in toluene, a catalyst was added, the mixture was heated and stirred, and the product was collected by vacuum distillation to obtain modified nitrile rubber.

[0013] S2: Modified nitrile rubber and 2-bromofluorene are placed in acetone, an accelerator is added, the temperature is raised to 45-55℃ and reacted for 3-5 hours. The product is collected by vacuum distillation to obtain a multifunctional rubber.

[0014] In this scheme, under the action of a catalyst, the carboxyl groups in the terminal carboxyl liquid nitrile rubber structure undergo a ring-opening reaction with the epoxy groups in the 2-(trifluoromethyl)ethylene oxide structure to obtain modified nitrile rubber. Then, under the action of an accelerator, the hydroxyl groups in the modified nitrile rubber structure undergo a substitution reaction with the active bromine in the 2-bromofluorene structure to obtain a multifunctional rubber. This multifunctional rubber, using nitrile rubber as a polymer backbone, can effectively enhance the toughness of polyurethane coatings. Simultaneously, the introduction of an organofluorine structure with extremely low surface energy into its structure enhances the corrosion resistance of the coating, enabling it to exist stably in corrosive media and resist erosion, thus enhancing the protective ability of the coating. Furthermore, the fluorene ring introduced into its structure effectively enhances the wear resistance of the polyurethane coating, making it less prone to wear during use and resulting in a longer service life.

[0015] Further, in step S1, the catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride, and tetrabutylammonium hydroxide.

[0016] Furthermore, in step S1, the temperature for heating and stirring is 80-90℃, and the time is 5-6 hours.

[0017] Furthermore, in step S2, the accelerator is either pyridine or potassium carbonate.

[0018] Furthermore, the preparation method of the modified filler includes the following steps:

[0019] Serpentine powder was placed in deionized water, ultrasonically dispersed, and then oleanolic acid was added. The mixture was heated to 85-90℃ and stirred thoroughly for 6-8 hours. After filtration, washing, and vacuum drying, the modified filler was obtained.

[0020] In this scheme, the hydroxyl groups on the surface of serpentine powder and the carboxyl groups in the oleanolic acid structure interact to obtain a modified filler with serpentine powder as the core and oleanolic acid as the shell. The oleanolic acid structure coated on the surface of this modified filler contains active hydroxyl groups, which can participate in the preparation process of polyurethane coatings, effectively enhancing the crosslinking density of polyurethane coatings. At the same time, with nanoparticles as the core, the interaction between the two can significantly enhance the wear resistance of polyurethane coatings, enabling them to be used in various friction scenarios without easily breaking and with a long service life. In addition, the oleanolic acid coated on its surface has excellent antibacterial properties. Fixing it on the surface of nanoparticles can prevent the migration of small oleanolic acid molecules during long-term use, which would reduce or eliminate the antibacterial effect. This greatly expands the application field of polyurethane coatings, enabling them to meet the needs of use in various environments.

[0021] Furthermore, the average particle size of the serpentine powder is 200 nm.

[0022] The beneficial effects of this invention are:

[0023] This invention incorporates multifunctional rubber and modified fillers into the preparation process of polyurethane coatings, resulting in polyurethane coatings with excellent wear resistance, antibacterial properties, and corrosion resistance. This meets the application requirements of coatings in special environments, greatly expanding the application fields of polyurethane coatings and extending the service life of polyurethane coatings.

[0024] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a flowchart illustrating the preparation process of the polyurethane coating of this invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and 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.

[0028] The preparation methods of the multifunctional rubber and modified filler in the following embodiments and comparative examples of the present invention are as follows:

[0029] I. Preparation of Multifunctional Rubber

[0030] S1: 3g of carboxyl-terminated liquid nitrile rubber and 2.6g of 2-(trifluoromethyl)ethylene oxide were placed in 80ml of toluene, 0.2g of tetrabutylammonium bromide was added, the mixture was heated to 80℃ and stirred thoroughly for 5h, and the product was collected by vacuum distillation to obtain modified nitrile rubber.

[0031] S2: 3.5g of modified nitrile rubber and 3.2g of 2-bromofluorene were placed in 90ml of acetone, 0.1g of pyridine was added, the mixture was heated to 45℃ and reacted for 3h. The product was collected by vacuum distillation to obtain a multifunctional rubber.

[0032] II. Preparation of Modified Fillers

[0033] 3g of serpentine powder with an average particle size of 200nm was placed in 100ml of deionized water and ultrasonically dispersed for 10min. Then, 2.8g of oleanolic acid was added, the temperature was raised to 85℃, and the mixture was stirred thoroughly for 6h. After filtration, washing, and vacuum drying, the modified filler was obtained. Example 1

[0034] A wear-resistant polyurethane coating comprises the following raw materials in parts by weight: 18 parts isophorone diisocyanate, 16 parts polytetrahydrofuran ether diol, 1 part dibutyltin dilaurate, 8 parts multifunctional rubber, 5 parts modified filler, 3 parts ethylene glycol, 2 parts triethylamine, and 80 parts deionized water.

[0035] The preparation of the wear-resistant polyurethane coating includes the following steps:

[0036] Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add dibutyltin dilaurate, mix evenly at 25°C, heat to 50°C and react for 1 hour, then continue heating to 75°C and react for 0.5 hours to obtain polyurethane prepolymer.

[0037] Step 2: Add ethylene glycol and multifunctional rubber to the polyurethane prepolymer, heat to 80℃ and react for 6 hours, then cool to 40℃ and add triethylamine and modified filler. After reacting for 2 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the wear-resistant polyurethane coating. Example 2

[0038] A wear-resistant polyurethane coating comprises the following raw materials in parts by weight: 20 parts isophorone diisocyanate, 17 parts polytetrahydrofuran ether diol, 1.5 parts dibutyltin dilaurate, 9 parts multifunctional rubber, 5.5 parts modified filler, 4 parts 1,4-butanediol, 2.5 parts triethylamine, and 90 parts deionized water.

[0039] The preparation of the wear-resistant polyurethane coating includes the following steps:

[0040] Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add dibutyltin dilaurate, mix evenly at 27°C, heat to 52°C and react for 1.5 hours, then continue heating to 80°C and react for 0.8 hours to obtain polyurethane prepolymer.

[0041] Step 2: Add ethylene glycol and multifunctional rubber to the polyurethane prepolymer, heat to 82℃ and react for 7 hours, then cool to 43℃ and add triethylamine and modified filler. After reacting for 2.5 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the wear-resistant polyurethane coating. Example 3

[0042] A wear-resistant polyurethane coating comprises the following raw materials in parts by weight: 22 parts isophorone diisocyanate, 18 parts polytetrahydrofuran ether diol, 2 parts stannous octoate, 10 parts multifunctional rubber, 6 parts modified filler, 5 parts propylene glycol, 3 parts triethylamine, and 100 parts deionized water.

[0043] The preparation of the wear-resistant polyurethane coating includes the following steps:

[0044] Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add stannous octoate, mix evenly at 30°C, heat to 55°C and react for 2 hours, then continue heating to 85°C and react for 1 hour to obtain polyurethane prepolymer.

[0045] Step 2: Add propylene glycol and multifunctional rubber to the polyurethane prepolymer, heat to 85℃ and react for 8 hours, then cool to 45℃ and add triethylamine and modified filler. After reacting for 3 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the wear-resistant polyurethane coating.

[0046] Comparative Example 1

[0047] A polyurethane coating comprises the following raw materials in parts by weight: 20 parts isophorone diisocyanate, 17 parts polytetrahydrofuran ether diol, 1.5 parts dibutyltin dilaurate, 9 parts multifunctional rubber, 4 parts 1,4-butanediol, 2.5 parts triethylamine, and 90 parts deionized water.

[0048] The preparation of the polyurethane coating includes the following steps:

[0049] Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add dibutyltin dilaurate, mix evenly at 27°C, heat to 52°C and react for 1.5 hours, then continue heating to 80°C and react for 0.8 hours to obtain polyurethane prepolymer.

[0050] Step 2: Add ethylene glycol and multifunctional rubber to the polyurethane prepolymer, heat to 82℃ and react for 7 hours, then cool to 43℃ and add triethylamine. After reacting for 2.5 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the polyurethane coating.

[0051] Comparative Example 2

[0052] A polyurethane coating comprises the following raw materials in parts by weight: 20 parts isophorone diisocyanate, 17 parts polytetrahydrofuran ether diol, 1.5 parts dibutyltin dilaurate, 5.5 parts modified filler, 4 parts 1,4-butanediol, 2.5 parts triethylamine, and 90 parts deionized water.

[0053] The preparation of the polyurethane coating includes the following steps:

[0054] Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add dibutyltin dilaurate, mix evenly at 27°C, heat to 52°C and react for 1.5 hours, then continue heating to 80°C and react for 0.8 hours to obtain polyurethane prepolymer.

[0055] Step 2: Add ethylene glycol to the polyurethane prepolymer, heat to 82℃ and react for 7 hours, then cool to 43℃ and add triethylamine and modified filler. After reacting for 2.5 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the polyurethane coating.

[0056] Comparative Example 3

[0057] A polyurethane coating comprises the following raw materials in parts by weight: 20 parts isophorone diisocyanate, 17 parts polytetrahydrofuran ether diol, 1.5 parts dibutyltin dilaurate, 9 parts modified nitrile rubber, 5.5 parts modified filler, 4 parts 1,4-butanediol, 2.5 parts triethylamine, and 90 parts deionized water.

[0058] The preparation of the polyurethane coating includes the following steps:

[0059] Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add dibutyltin dilaurate, mix evenly at 27°C, heat to 52°C and react for 1.5 hours, then continue heating to 80°C and react for 0.8 hours to obtain polyurethane prepolymer.

[0060] Step 2: Add ethylene glycol and modified nitrile rubber to the polyurethane prepolymer, heat to 82℃ and react for 7 hours, then cool to 43℃ and add triethylamine and modified filler. After reacting for 2.5 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the polyurethane coating.

[0061] Comparative Example 4

[0062] A polyurethane coating comprises the following raw materials in parts by weight: 20 parts isophorone diisocyanate, 17 parts polytetrahydrofuran ether diol, 1.5 parts dibutyltin dilaurate, 9 parts multifunctional rubber, 5.5 parts serpentine powder, 4 parts 1,4-butanediol, 2.5 parts triethylamine, and 90 parts deionized water.

[0063] The preparation of the polyurethane coating includes the following steps:

[0064] Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add dibutyltin dilaurate, mix evenly at 27°C, heat to 52°C and react for 1.5 hours, then continue heating to 80°C and react for 0.8 hours to obtain polyurethane prepolymer.

[0065] Step 2: Add ethylene glycol and multifunctional rubber to the polyurethane prepolymer, heat to 82℃ and react for 7 hours, then cool to 43℃ and add triethylamine and serpentine powder. After reacting for 2.5 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the polyurethane coating.

[0066] Performance testing

[0067] The polyurethane coatings prepared in Examples 1-3 and Comparative Examples 1-4 were coated onto steel plates conforming to specifications and cured at 80°C for 1 hour to prepare samples conforming to specifications. Salt spray resistance was tested according to standard GB / T1771-2007 to determine the corrosion resistance of the samples. Abrasion resistance was tested according to standard GB / T1768-2006 to determine the abrasion resistance; the lower the abrasion resistance, the stronger the abrasion resistance. Antibacterial properties were tested according to standard GB / T21866-2008 to determine the antibacterial effect. Specific test results are shown in the table below:

[0068]

[0069] As shown in the table above, the samples prepared in Examples 1-3 all exhibit excellent corrosion resistance, wear resistance, and antibacterial properties, meeting the requirements for use in various environments. The sample prepared in Comparative Example 1 did not contain any modified filler, resulting in poor antibacterial properties and average wear resistance. The sample prepared in Comparative Example 2 did not contain any multifunctional rubber, resulting in poor corrosion resistance and wear resistance compared to the examples, but it exhibited excellent antibacterial effects. The sample prepared in Comparative Example 3 directly incorporated modified nitrile rubber without introducing fluorene rings into its structure, resulting in wear resistance compared to the examples. The sample prepared in Comparative Example 4 directly incorporated serpentine powder, indicating poor wear resistance, corrosion resistance, and antibacterial properties. This is because the serpentine powder was not uniformly dispersed in the matrix material due to the lack of modification.

[0070] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0071] The above content is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the scope defined by the inventive concept, they should all fall within the protection scope of the present invention.

Claims

1. A production process for a wear-resistant polyurethane coating, characterized in that, The production process includes the following steps: Step 1: Mix isophorone diisocyanate and polytetrahydrofuran ether diol, purge with nitrogen, add organotin catalyst, mix evenly at 25-30℃, heat to 50-55℃ and react for 1-2 hours, then continue heating to 75-85℃ and react for 0.5-1 hours to obtain polyurethane prepolymer. Step 2: Add ethylene glycol and multifunctional rubber to the polyurethane prepolymer, heat to 80-85℃ and react for 6-8 hours, then cool to 40-45℃ and add triethylamine and modified filler. After reacting for 2-3 hours, add deionized water, stir at high speed, and allow to defoam naturally to obtain the wear-resistant polyurethane coating. The wear-resistant polyurethane coating comprises the following raw materials in parts by weight: 18-22 parts isophorone diisocyanate, 16-18 parts polytetrahydrofuran ether diol, 1-2 parts organotin catalyst, 8-10 parts multifunctional rubber, 5-6 parts modified filler, 3-5 parts small molecule chain extender, 2-3 parts triethylamine, and 80-100 parts deionized water. The preparation method of the multifunctional rubber includes the following steps: S1: The carboxyl-terminated liquid nitrile rubber and 2-(trifluoromethyl)ethylene oxide were placed in toluene, a catalyst was added, the mixture was heated and stirred, and the product was collected by vacuum distillation to obtain modified nitrile rubber. S2: Modified nitrile rubber and 2-bromofluorene are placed in acetone, an accelerator is added, the temperature is raised to 45-55℃ and reacted for 3-5 hours, the product is collected by vacuum distillation to obtain a multifunctional rubber; The method for preparing the modified filler includes the following steps: Serpentine powder was placed in deionized water, ultrasonically dispersed, and then oleanolic acid was added. The mixture was heated to 85-90℃ and stirred thoroughly for 6-8 hours. After filtration, washing, and vacuum drying, the modified filler was obtained.

2. The production process of a wear-resistant polyurethane coating according to claim 1, characterized in that, The organotin catalyst is any one of dibutyltin dilaurate and stannous octoate; the small molecule chain extender is any one of ethylene glycol, 1,4-butanediol, and propylene glycol.

3. The production process of a wear-resistant polyurethane coating according to claim 1, characterized in that, In step S1, the catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride, and tetrabutylammonium hydroxide.

4. The production process of a wear-resistant polyurethane coating according to claim 1, characterized in that, In step S1, the temperature for heating and stirring is 80-90℃, and the time is 5-6 hours.

5. The production process of a wear-resistant polyurethane coating according to claim 1, characterized in that, In step S2, the accelerator is either pyridine or potassium carbonate.

6. The production process of a wear-resistant polyurethane coating according to claim 1, characterized in that, The average particle size of the serpentine powder is 200 nm.

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