A hydrophilic lubricating coating solution and its preparation method and application

Abstract

This invention provides a hydrophilic lubricating coating solution, its preparation method, and its application, belonging to the field of medical device technology. The hydrophilic lubricating coating solution of this invention comprises the following raw materials in parts by weight: 1-4 parts of polyurethane prepolymer, 91-99 parts of mixed solvent, 2-3 parts of 1-methyl-2-pyrrolidone, 1.0-1.5 parts of 3-aminopropyltriethoxysilane, and 0-4 parts of polyvinylpyrrolidone. The drainage tube is immersed in the hydrophilic lubricating coating solution, then removed, air-dried, and oven-dried to obtain the hydrophilic lubricating coating. The hydrophilic lubricating coating exhibits good biocompatibility, a low coefficient of friction, and excellent hydrophilic properties, possessing strong adhesion. This enables silicone rubber drainage tubes to meet the requirements of clinical medical applications and extends their service life, providing patients with a better user experience.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a hydrophilic lubricating coating solution, its preparation method, and its application. Background Technology

[0002] Silicone rubber, a polymeric elastic drainage tube that combines inorganic and organic properties, is composed primarily of alternating silicon and oxygen atoms (-Si-O-Si-), with hydrocarbon or substituted hydrocarbon organic groups attached to the silicon atoms. These groups are typically methyl or unsaturated vinyl groups (usually accounting for no more than 0.1%), giving silicone rubber excellent thermal stability, aging resistance, and resistance to ultraviolet (UV) and ozone corrosion. Due to its anti-aging properties, high transparency, good biocompatibility, and excellent temperature resistance, silicone rubber has been widely used in the biological and medical fields. However, due to the inherent properties of silicone rubber, the interface friction between medical silicone rubber and the patient during use can cause pain and easily tear wounds, leading to inflammation and other symptoms. Therefore, improving the lubricity of the silicone rubber surface and reducing boundary friction can reduce the risk of complications, thus providing patients with a safer and more comfortable experience, which has significant application potential.

[0003] Currently, the simplest and most effective method is to coat the silicone rubber surface with a lubricating coating, attaching hydrophilic groups such as pyrrolidone, carboxyl, and amide groups. Thanks to the properties of these hydrophilic groups, the modified drainage tube surface exhibits excellent hydrophilicity and lubricity, thereby reducing boundary friction and significantly improving its anti-fouling performance. Simultaneously, the ultra-thin hydrophilic coating does not alter the properties of the silicone rubber itself. The main drainage tube systems include PEG, polyacrylamide (PAM), and hyaluronic acid (HA).

[0004] PEG is a branched polyether compound containing multiple ethylene oxide and hydroxyl groups, giving it excellent water solubility and biocompatibility. These groups can form hydrogen bonds with water, making PEG highly hydrophilic, reducing surface friction. Furthermore, the very soft PEG molecular chains can form a uniform lubricating film on the substrate surface, making contact between friction surfaces smoother and improving lubrication. Studies have found that PEG coatings can block long-range attraction between bacteria and substrates and introduce a repulsive steric effect, thereby altering the hydrophilicity and frictional properties of the duct surface, resulting in superior lubrication performance. PAM is a highly hydrophilic polymer with strong water absorption. When water molecules interact with the polar groups in PAM molecules, a "lubricating layer" of water molecules forms on the particle surface. This lubricating layer significantly reduces friction between particles, making the surface slippery. HA, also known as hyaluronic acid, is a polysaccharide macromolecule and a major component of the extracellular matrix. It possesses unique physicochemical and biological properties, exhibiting excellent biocompatibility and biodegradability. Currently, although research on HA lubrication has been gradually applied to the surface modification of medical catheters, there are still unresolved problems regarding the adhesion and stability of the coating to the catheter surface, which limits its widespread application in the medical field. Summary of the Invention

[0005] The purpose of this invention is to provide a hydrophilic lubricating coating solution, its preparation method, and its application, so as to solve the problems of high friction coefficient and low adhesion of lubricating coatings in the prior art.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] This invention provides a hydrophilic lubricating coating solution, which comprises the following raw materials in parts by weight:

[0008]

[0009] Preferably, the mixed solvent comprises acetone, ethyl lactate, and tetrahydrofuran, wherein the mass ratio of acetone, ethyl lactate, and tetrahydrofuran is 56–59:24–27:11–13.

[0010] Preferably, the hydrophilic lubricating coating solution comprises the following raw materials in parts by weight:

[0011]

[0012] Preferably, the hydrophilic lubricating coating solution comprises the following raw materials in parts by weight:

[0013]

[0014]

[0015] The present invention also provides a method for preparing the above-described hydrophilic lubricating coating solution, comprising the following steps:

[0016] (1) Mix the polyurethane prepolymer and the mixed solvent to obtain mixed solution A;

[0017] (2) Mix 1-methyl-2-pyrrolidone and 3-aminopropyltriethoxysilane to obtain mixed solution B;

[0018] (3) After combining mixed solution A and mixed solution B, polyvinylpyrrolidone is added to obtain a hydrophilic lubricating coating solution.

[0019] The present invention also provides an application of the above-mentioned hydrophilic lubricating coating solution in the preparation of a hydrophilic lubricating coating, comprising the following steps: immersing a drainage tube in the hydrophilic lubricating coating solution, removing it and then air-drying or baking it to obtain a hydrophilic lubricating coating.

[0020] Preferably, the drainage tube is cleaned with heptane and then immersed in a hydrophilic lubricating coating solution.

[0021] Preferably, the immersion time is 4 to 6 minutes.

[0022] Preferably, the drying is carried out in the air for 20 to 40 minutes.

[0023] Preferably, the drying temperature is 60-80°C and the time is 0.5-1.5 hours; after drying, the drainage tube is placed in the air for 24 hours before use.

[0024] The beneficial effects of this invention are:

[0025] In this invention, the polyurethane prepolymer serves as a binder. After curing with the silane coupling agent 3-aminopropyltriethoxysilane, it forms an interpenetrating network structure, which modifies the interface of the silicone rubber drainage tube, enhancing the adhesion and durability of the coating. 1-Methyl-2-pyrrolidone and 3-aminopropyltriethoxysilane are used as additives; their strong solubility and bonding properties make the coating more stable. Polyvinylpyrrolidone, as a hydrophilic lubricant, imparts hydrophilic lubricating properties to the coating.

[0026] This invention utilizes a polyurethane prepolymer, a mixed solvent, 1-methyl-2-pyrrolidone, 3-aminopropyltriethoxysilane, and polyvinylpyrrolidone to prepare a hydrophilic lubricating coating solution. A silicone rubber drainage tube is then placed in this solution to form a hydrophilic lubricating coating on the tube. This coating exhibits good biocompatibility, a low coefficient of friction, excellent hydrophilicity, and strong adhesion, enabling the silicone rubber drainage tube to meet the requirements of clinical medical applications and extending its service life, thus providing patients with a better user experience. Attached Figure Description

[0027] Figure 1 The graph shows the friction coefficient variation curves of an uncoated silicone rubber drain tube and a silicone rubber drain tube coated with a hydrophilic lubricating coating. PDMS represents the uncoated silicone rubber drain tube, 1 represents the silicone rubber drain tube coated with the hydrophilic lubricating coating solution of Example 1, 2 represents the silicone rubber drain tube coated with the hydrophilic lubricating coating solution of Example 2, 3 represents the silicone rubber drain tube coated with the hydrophilic lubricating coating solution of Example 3, 4 represents the silicone rubber drain tube coated with the hydrophilic lubricating coating solution of Example 4, and 5 represents the silicone rubber drain tube coated with the hydrophilic lubricating coating solution of Example 5.

[0028] Figure 2 A comparison chart of the average friction coefficients of the silicone rubber drainage tubes with hydrophilic lubricating coatings in Application Example 1;

[0029] Figure 3 A comparison diagram of the water contact angles of an uncoated silicone rubber drain tube and a silicone rubber drain tube with a hydrophilic lubricating coating in Application Example 1;

[0030] Figure 4 A comparison chart showing the adhesion test results of the silicone rubber drainage tube with a hydrophilic lubricating coating in Application Example 1;

[0031] Figure 5 The graph shows the coefficient of friction variation of the silicone rubber drainage tube with PDMS as the uncoated silicone rubber and the silicone rubber drainage tube coated with the coating solutions of Comparative Example 2 and Comparative Example 3.

[0032] Figure 6 The image shows a comparison of the water contact angles of uncoated silicone rubber drainage tubes with PDMS and silicone rubber drainage tubes coated with the coating solutions of Comparative Examples 2 and 3. Detailed Implementation

[0033] This invention provides a hydrophilic lubricating coating solution, which comprises the following raw materials in parts by weight:

[0034]

[0035] In this invention, the mixed solvent comprises acetone, ethyl lactate, and tetrahydrofuran, wherein the mass ratio of acetone, ethyl lactate, and tetrahydrofuran is 56-59:24-27:11-13.

[0036] This invention uses acetone, ethyl lactate, and tetrahydrofuran as solvents, which have good solubility and volatility properties, can effectively dissolve polyurethane prepolymers and volatilize rapidly after the coating is formed.

[0037] In this invention, the hydrophilic lubricating coating solution comprises the following raw materials in parts by weight:

[0038]

[0039] In this invention, the hydrophilic lubricating coating solution comprises the following raw materials in parts by weight:

[0040]

[0041] The present invention also provides a method for preparing the above-described hydrophilic lubricating coating solution, comprising the following steps:

[0042] (1) Mix the polyurethane prepolymer and the mixed solvent to obtain mixed solution A;

[0043] (2) Mix 1-methyl-2-pyrrolidone and 3-aminopropyltriethoxysilane to obtain mixed solution B;

[0044] (3) After combining mixed solution A and mixed solution B, polyvinylpyrrolidone is added to obtain a hydrophilic lubricating coating solution.

[0045] The present invention also provides an application of the above-mentioned hydrophilic lubricating coating solution in the preparation of a hydrophilic lubricating coating, comprising the following steps: immersing a drainage tube in the hydrophilic lubricating coating solution, removing it and then air-drying or baking it to obtain a hydrophilic lubricating coating.

[0046] In this invention, the drainage tube is cleaned with heptane and then immersed in a hydrophilic lubricating coating solution.

[0047] In this invention, the heptane is used to clean the surface of the drainage tube. It has excellent cleaning and volatile properties, which can effectively clean the surface of the drainage tube and avoid the presence of residues. It expands the drainage tube to a certain extent. During coating, the hydrophilic lubricating coating solution enters the surface of the silicone rubber drainage tube, making the adhesion stronger.

[0048] In this invention, the immersion time is 4 to 6 minutes, preferably 5 minutes.

[0049] In this invention, the drying is carried out in the air for 20 to 40 minutes, preferably 25 to 35 minutes, and more preferably 30 minutes.

[0050] In this invention, the drying temperature is 60-80°C and the time is 0.5-1.5 hours; after drying, the drainage tube is placed in the air for 24 hours before use.

[0051] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0052] The detailed information of each raw material used in the embodiments of the present invention is as follows:

[0053] Polyurethane prepolymer (Xinyuhong, 99%), polyvinylpyrrolidone K30 (AR, Zhonglian Reagent), 3-aminopropyltriethoxysilane (aladdin, 221.37MW), ethyl lactate (Innochem, 98%), tetrahydrofuran (AR, Tianjin Beichen Fangzheng Reagent Factory), 1-methyl-2-pyrrolidone (aladdin, AR), acetone (AR, Laiyang Economic and Technological Development Zone Fine Chemical Plant), heptane (aladdin, AR).

[0054] Example 1

[0055] Mix 1 part of polyurethane prepolymer, 56 parts of acetone, 24 parts of ethyl lactate, and 11 parts of tetrahydrofuran until completely dissolved to obtain mixed solution A; mix 2.6 parts of 1-methyl-2-pyrrolidone and 1.2 parts of 3-aminopropyltriethoxysilane (APTES) and let stand for 5 minutes to obtain mixed solution B; combine mixed solutions A and B and stir for 24 hours. As the stirring time increases, white particles or flocculent precipitates appear in the solution, thus obtaining the hydrophilic lubricating coating solution.

[0056] Example 2

[0057] Mix 2 parts of polyurethane prepolymer, 57 parts of acetone, 25 parts of ethyl lactate, and 12 parts of tetrahydrofuran until completely dissolved to obtain mixed solution A. Mix 2.6 parts of 1-methyl-2-pyrrolidone and 1.2 parts of 3-aminopropyltriethoxysilane until uniform and let stand for 5 minutes to obtain mixed solution B. Combine mixed solutions A and B and stir for 24 hours. As the stirring time increases, white particles or flocculent precipitates appear in the solution. Finally, add 1 part of polyvinylpyrrolidone K30 and mix until uniform to obtain the hydrophilic lubricating coating solution.

[0058] Example 3

[0059] Mix 3 parts of polyurethane prepolymer, 58 parts of acetone, 26 parts of ethyl lactate, and 13 parts of tetrahydrofuran until completely dissolved to obtain mixed solution A. Mix 2.6 parts of 1-methyl-2-pyrrolidone and 1.2 parts of 3-aminopropyltriethoxysilane until uniform and let stand for 5 minutes to obtain mixed solution B. Combine mixed solutions A and B and stir for 24 hours. As the stirring time increases, white particles or flocculent precipitates appear in the solution. Finally, add 2 parts of polyvinylpyrrolidone K30 and mix well to obtain the hydrophilic lubricating coating solution.

[0060] Example 4

[0061] Mix 3.8 parts of polyurethane prepolymer, 56 parts of acetone, 24 parts of ethyl lactate, and 11 parts of tetrahydrofuran until completely dissolved to obtain mixed solution A. Mix 2.6 parts of 1-methyl-2-pyrrolidone and 1.2 parts of 3-aminopropyltriethoxysilane until uniform and let stand for 5 minutes to obtain mixed solution B. Combine mixed solutions A and B and stir for 24 hours. As the stirring time increases, white particles or flocculent precipitates appear in the solution. Finally, add 3 parts of polyvinylpyrrolidone K30 and mix until uniform to obtain the hydrophilic lubricating coating solution.

[0062] Example 5

[0063] Mix 4 parts of polyurethane prepolymer, 56 parts of acetone, 24 parts of ethyl lactate, and 11 parts of tetrahydrofuran until completely dissolved to obtain mixed solution A. Mix 2.6 parts of 1-methyl-2-pyrrolidone and 1.2 parts of 3-aminopropyltriethoxysilane until completely dissolved to obtain mixed solution B. Combine mixed solutions A and B and stir for 24 hours. As the stirring time increases, white particles or flocculent precipitates appear in the solution. Finally, add 4 parts of polyvinylpyrrolidone K30 and mix thoroughly to obtain the hydrophilic lubricating coating solution.

[0064] Comparative Example 1

[0065] The difference from Example 3 is that 3-aminopropyltriethoxysilane was not added, while all other conditions were the same.

[0066] Comparative Example 2

[0067] The difference from Example 4 is that 1-methyl-2-pyrrolidone was not added, while all other conditions were the same.

[0068] Comparative Example 3

[0069] The difference from Example 5 is that polyacrylic acid (AR, Comio reagent) was used instead of polyvinylpyrrolidone K30, while all other conditions were the same.

[0070] Application Example 1

[0071] The medical silicone rubber drainage tube was immersed in heptane for 10 seconds, then wiped dry and air-dried for 5 minutes. Then it was immersed in the hydrophilic lubricating coating solutions of Examples 1-5 and Comparative Examples 1-3 respectively. The tubes were removed after immersion in the hydrophilic lubricating coating solutions of Examples 1-5 and Comparative Examples 1-2 for 5 minutes, and then immersed in the lubricating coating solution of Comparative Example 3 for 30 minutes. After air-driing for 30 minutes, the silicone rubber drainage tubes were placed in an oven and dried at 71°C for 1 hour. After drying, they were placed in the air for 24 hours before use. The silicone rubber drainage tubes with hydrophilic lubricating coatings were numbered 1, 2, 3, 4, and 5, respectively, where 1, 2, 3, 4, and 5 correspond to the hydrophilic lubricating coating solutions of Examples 1-5.

[0072] Performance testing:

[0073] (1) Friction Performance Test: The friction performance of medical silicone rubber drainage tubes with lubricating coating in an aqueous environment was tested using a high-speed reciprocating friction and wear tester (MDW-02A, Jinan Yihua Tribology Testing Technology Co., Ltd.). The friction coefficient of the silicone rubber drainage tubes with stainless steel balls was tested under conditions of 5N and 1Hz. 50mL of deionized water was added to the sample tank, and the loading pressure was 5N. Each sample was tested 3 times, and the average value of the test results was taken. The friction coefficient test results are as follows: Figure 1 , 2 As shown.

[0074] (2) Surface wettability test: The surface wettability of different samples was measured using a dynamic / static contact angle meter (JCW-1, Shanghai Fangrui Instrument Co., Ltd.). The droplet used for each measurement was 5 μL of deionized water. Six points were randomly tested for each sample. After the water droplet stabilized, the contact angle (WCA) was measured and the average value was taken.

[0075] (3) Adhesion test: The bonding strength of the coating was tested using the ISO2409-2007 grid method. First, a grid of 10×10mm was drawn on the surface of the coated PDMS sample with a grid knife under uniform pressure. 3M tape was then attached to the sample surface and quickly peeled off. The delamination position of the coating and the grid was observed.

[0076] Results analysis:

[0077] Comparative Example 1, due to the absence of 3-aminopropyltriethoxysilane, did not result in the formation of a coating on the PDMS sample. The experimental results for Comparative Examples 2 and 3 are as follows: Figure 5 , 6As shown, in Comparative Example 2, without the addition of 1-methyl-2-pyrrolidone, the water contact angle of the coating formed was lower than that of the original PDMS, but the coefficient of friction was higher than that of the unmodified PDMS, so the modification was meaningless. Comparative Example 3 used polyacrylic acid to make a lubricating coating solution, and the resulting lubricating coating had a small water contact angle and a low coefficient of friction. However, the coating process took too long and could only be deposited on a flat surface, so it had no practical application significance.

[0078] pass Figure 1 and Figure 3 It can be seen that the silicone rubber drainage tube coated with a hydrophilic lubricating coating of the present invention has good friction performance and hydrophilicity. Figure 2 This is a comparison chart of the average friction coefficients of the silicone rubber drainage tubes with hydrophilic lubricating coatings used in Application Example 1. Figure 2 and Figure 3 It can be seen that in Example 4, with 3.8 parts of polyurethane prepolymer, 56 parts of acetone, 24 parts of ethyl lactate, 11 parts of tetrahydrofuran, 2.6 parts of 1-methyl-2-pyrrolidone, 1.2 parts of APTES, and 3 parts of polyvinylpyrrolidone K30, the hydrophilic lubricating coating obtained had the lowest average coefficient of friction of 0.13 and a water contact angle of 62.5°, which is higher than that in Example 5. However, adhesion performance tests show that the adhesion of the hydrophilic lubricating coating decreased when 4 parts of polyvinylpyrrolidone K30 were used (see details). Figure 4 This will cause the hydrophilic lubricating coating to wear out during the friction process, resulting in an increase in the coefficient of friction. Therefore, the hydrophilic lubricating coating solution in Example 4 has the optimal ratio.

[0079] from Figure 4 It can be seen that the coating exhibits the best adhesion performance without the addition of polyvinylpyrrolidone (PVP), with no coating observed adhering to the tape. As the PPVP content increases, the coating's adhesion performance gradually decreases. When the PPVP content is 4 parts, the coating is observed to be completely adhered to the tape. Combining the friction coefficient and contact angle data, it can be concluded that adding 3 parts PPVP results in a coating with good adhesion and lubrication properties.

[0080] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A hydrophilic lubricating coating solution, characterized in that, The hydrophilic lubricating coating solution comprises the following raw materials in parts by weight: 2-4 parts of polyurethane prepolymer 91-99 parts of mixed solvent 2-3 parts of 1-methyl-2-pyrrolidone 1.0 to 1.5 parts of 3-aminopropyltriethoxysilane 3 parts polyvinylpyrrolidone; The mixed solvent comprises acetone, ethyl lactate, and tetrahydrofuran, wherein the mass ratio of acetone, ethyl lactate, and tetrahydrofuran is 56–59:24–27:11–13.

2. The hydrophilic lubricating coating solution according to claim 1, characterized in that, The hydrophilic lubricating coating solution comprises the following raw materials in parts by weight: 3.8 parts of polyurethane prepolymer 91-99 parts of mixed solvent 2-3 parts of 1-methyl-2-pyrrolidone 1.0 to 1.5 parts of 3-aminopropyltriethoxysilane Three parts of polyvinylpyrrolidone.

3. The method for preparing the hydrophilic lubricating coating solution according to claim 1 or 2, characterized in that, Includes the following steps: (1) Mix the polyurethane prepolymer and the mixed solvent to obtain mixed solution A; (2) Mix 1-methyl-2-pyrrolidone and 3-aminopropyltriethoxysilane to obtain mixed solution B; (3) After combining mixed solution A and mixed solution B, polyvinylpyrrolidone is added to obtain a hydrophilic lubricating coating solution.

4. The application of the hydrophilic lubricating coating solution according to claim 1 or 2 in the preparation of hydrophilic lubricating coatings, characterized in that, The process includes the following steps: immersing the drainage tube in a hydrophilic lubricating coating solution, removing it, air-drying, and then baking it to obtain the hydrophilic lubricating coating.

5. The application of the hydrophilic lubricating coating solution according to claim 4 in the preparation of a hydrophilic lubricating coating, characterized in that, The drainage tube is cleaned with heptane and then immersed in a hydrophilic lubricating coating solution.

6. The application of the hydrophilic lubricating coating solution according to claim 5 in the preparation of a hydrophilic lubricating coating, characterized in that, The immersion time is 4 to 6 minutes.

7. The application of the hydrophilic lubricating coating solution according to claim 6 in the preparation of a hydrophilic lubricating coating, characterized in that, The drying process takes place in the air and lasts for 20 to 40 minutes.

8. The application of the hydrophilic lubricating coating solution according to claim 5 or 7 in the preparation of a hydrophilic lubricating coating, characterized in that, The drying temperature is 60-80℃ and the time is 0.5-1.5h; after drying, the drainage tube is placed in the air for 24h before use.

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