A method for modifying the inner and outer surfaces of a silicone tube for a precision water pollution detector

Abstract

The present invention discloses a method for modifying the inner and outer surfaces of a silica gel tube used in a precision water pollution detector. Using a commercially available medical-grade silica gel hose, a chitosan nitric acid aqueous solution with a chitosan mass fraction of 1%, C 26 H 42 N2O 37 S5, C4H5NO3, C8H 18 C l N3, aniline, ammonium persulfate, a hydrochloric acid aqueous solution with a solute mass fraction of 10%, nano-silica, and sodium chloride as raw materials, the inner surface of the silica gel tube is subjected to hydrophobic and corrosion-resistant modification treatment, and the outer surface of the silica gel tube is subjected to anti-fouling and weather-resistant modification treatment. After modification by the present invention, the inner surface of the silica gel tube is hydrophobic and corrosion-resistant, the outer surface is anti-fouling and weather-resistant, resistant to bending, and self-recovering.

Description

Technical Field

[0001] The invention relates to a method for manufacturing a special hose for precision instruments, in particular to a method for modifying the inner and outer surfaces of a silicone tube for a precision water pollution degree detector. Background Art

[0002] The structure of silicone tube: silicone rubber is a chain structure formed by SI-O (silicon-oxygen) bonds. The SI-O bond is 443.5KJ / MOL, which is much higher than the CC bond energy (355KJ / MOL). Due to its common molecular structure, silicone tube has better heat resistance, electrical insulation, chemical stability, etc. than other rubber materials.

[0003] However, due to its hydrophilicity and the limitation of vulcanization process, when it is applied to the field corresponding to the precision water pollution detector, the inner surface contacts the liquid with complex components, and the outer surface is subjected to the complex environment such as light, heat, dust, etc., which may cause the following problems:

[0004] 1. Poor weather resistance. After a period of use, the silicone tube wall will bubble inside and outside, and in severe cases, the tube wall will rupture;

[0005] 2. After long-term use, the exterior becomes yellow, the overall structure becomes brittle, and the mechanical properties decrease;

[0006] 3. Silica gel is relatively hydrophilic, and liquid easily accumulates on the inner surface, affecting the test results;

[0007] 4. After long-term use, the inner surface corrodes, making it easier for liquid to accumulate on the inner surface, affecting the test results.

[0008] However, there is no relevant technology in the current existing technology that can solve the above problems, resulting in the detection accuracy of precision detection instruments using silicone tubes as infusion pipelines always having an obvious upper limit.

[0009] Therefore, there is a need for a method for modifying the inner and outer surfaces of a silicone tube for a precision water pollution detector, which has a hydrophobic and corrosion-resistant inner surface, and an anti-fouling and weather-resistant outer surface, and is resistant to bending and self-recovery. Summary of the invention

[0010] The present invention aims to provide a method for modifying the inner and outer surfaces of a silicone tube for a precision water pollution detector, which has a hydrophobic and corrosion-resistant inner surface and a stain-resistant and weather-resistant outer surface, a bending-resistant and self-recovering outer surface.

[0011] In order to achieve the above object, the present invention adopts the following technical scheme: a method for modifying the inner and outer surfaces of a silicone tube for a precision water pollution detector, comprising the following stages:

[0012] S1: Raw material preparation

[0013] ① Raw material preparation: prepare sufficient commercial medical grade silicone hose, chitosan nitric acid aqueous solution with a chitosan mass fraction of 1%, C 26 H 42 N2O 37 S5, C4H5NO3, C8H 18 ClN3, aniline, ammonium persulfate, 10% hydrochloric acid aqueous solution, nano-silicon dioxide, sodium chloride;

[0014] ② Preparation of auxiliary materials: prepare sufficient acetone, ethanol, deionized water, hydrogen peroxide, MES buffer with a pH value of 5.2-5.8, and sodium hydroxide aqueous solution with a solute mass fraction of 1%;

[0015] S2: Pre-preparation

[0016] ① The commercially available medical-grade silicone hose prepared in step ① of stage S1 is completely immersed in the acetone solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned; then it is completely immersed in the ethanol solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned; finally, it is completely immersed in the sodium hydroxide aqueous solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned, to obtain a clean micro-etched silicone tube;

[0017] ② The clean micro-etched silicone tube obtained in step ① is completely immersed in the hydrogen peroxide prepared in step ② of stage S1 for 70-80 minutes, then the treated clean silicone tube is taken out and completely immersed in the deionized water prepared in step ② of stage S1, and ultrasonic oscillation is used to clean the inner and outer surfaces of the tube to obtain a pretreated silicone tube;

[0018] ③ Place the pretreated silicone tube obtained in step ② in a drying electric oven and bake at a temperature of 55°C-75°C until the pretreated silicone tube is completely dried to obtain the silicone tube to be modified;

[0019] S3: Internal surface treatment

[0020] ① Mix the aniline prepared in step ① of stage S1 with the aqueous hydrochloric acid solution in a volume ratio of 1:(24-27) and place in a glass container, place in an ice-water mixture bath and stir with electromagnetic stirring until the mixture is uniform, to obtain a mixed solution A;

[0021] ② Mix the nano-silicon dioxide prepared in step ① of stage S1 and the deionized water prepared in step ② of stage S1 to form a turbid liquid B in a mass ratio of 3:(6.8-7.2);

[0022] ③ Mix the turbid solution B obtained in step ② and the mixed solution A obtained in step ① at a volume ratio of 1:(4.9-5.6) and stir evenly to obtain a mixed solution C;

[0023] ④ In stage S2, the mixed solution C obtained in step ③ is introduced into the silicone tube to be modified obtained in step ③ to obtain a reaction system;

[0024] ⑤ Place the reaction system obtained in step ④ in an ice-water mixture bath, add 3 to 3.1 times the mass of aniline added in step ① of the ammonium persulfate prepared in step S1 ① to the mixed solution C, and the reaction system begins to react on the inner surface of the silicone tube to be modified; react for 15 min to 20 min, and after the reaction is completed, clean the inner and outer surfaces of the treated silicone tube to obtain an inner surface modified silicone tube;

[0025] S4: External surface treatment

[0026] ① Block both ends of the inner surface modified silicone tube obtained in step ⑤ of stage S3 to prevent the liquid from entering the interior of the tube, thereby obtaining a closed silicone tube;

[0027] ② The sealed silicone tube obtained in step ① is completely immersed in the MES buffer prepared in step ② of stage S1 for 2.5h-3h, taken out and then completely immersed in the chitosan nitric acid aqueous solution prepared in step ① of stage S1, and the reaction system is placed in a water bath shaker for treatment. The reaction parameters are: temperature 28°C-35°C, stirring rate 120rpm-150rpm, treatment time 18h-22h, and a pre-treated tube is obtained after the reaction is completed;

[0028] ③ After cleaning the primary pretreatment tube obtained in step ② with deionized water, completely immerse it in the sodium hydroxide aqueous solution prepared in step ② of stage S1, and let it stand for 12h-14h. After the treatment, take it out, clean it and dry it to obtain a primary treatment tube;

[0029] ④Put the C prepared in step ① of stage S1 26 H 42 N2O 37 S5, sodium chloride, C4H5NO3, C8H 18 ClN3 is mixed uniformly in a mass ratio of (325-330):(4.1-4.4):1:(3.3-3.5), and MES buffer is used as a solvent to prepare a mixed solution D;

[0030] ⑤ Completely immerse the once treated tube obtained in step ③ in the MES buffer prepared in step ② of stage S1 for 2.5h-3h, take it out and then completely immerse it in the mixed solution D prepared in step ④, place this reaction system in a water bath shaker for treatment, the reaction parameters are: temperature 28℃-35℃, stirring rate 120rpm-150rpm, treatment time 18h-22h, after the reaction is completed, obtain the outer surface treated tube, clean and dry it to obtain the required inner and outer surface modified silicone tube.

[0031] Compared with the prior art, the present invention has the following advantages due to the adoption of the above technical solution:

[0032] (1) The present invention first performs a hydrophobic modification treatment on the inner surface of the silicone tube. Compared with the hydrophilic inner surface of the original silicone tube, the various modified functional substances such as aniline cations, free radicals and their oligomers involved in the modification of the present invention are more easily adsorbed on the hydrophobic inner surface after the modification of the present invention, and the density of nucleation centers is greater, so the apparent quality, thickness and corrosion resistance of the inner surface film are improved to varying degrees. The thickness of the film on the inner surface of the silicone tube of the present invention is between 40nm and 100nm, and the contact angle of the film is 117.1°-122.6° (the contact angle of the original silicone tube surface is about 80°). Compared with the original silicone, it has better hydrophobicity and corrosion resistance.

[0033] (2) As for the protective performance of the modified outer surface of the present invention, the water permeability and water holding capacity are both reduced compared with the silicone matrix, and the oxidation resistance and heat resistance are significantly increased. As for the radial tensile strength, axial tensile strength, elongation at break and Young's modulus of the modified pipeline, the elongation at break and Young's modulus are basically unchanged, and the other properties are increased compared with the unmodified original silicone tube, and have significantly better anti-bending performance. In summary, the modification of the outer surface of the silicone tube by the present invention will increase the mechanical properties of the silicone tube, but will not reduce its ductility and elasticity, and at the same time, the self-recovery and scratch resistance are significantly increased.

[0034] Therefore, the invention has the characteristics of water repellency and corrosion resistance on the inner surface, and anti-fouling and weather resistance, bending resistance and self-recovery on the outer surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a micrograph of the inner surface of the silicone tube of the present invention;

[0036] Figure 2 This is an atomic force microscope photo of the inner surface of the silicone tube after treatment of the present invention;

[0037] Figure 3 The surface micrograph of the outer surface of the silicone tube of the present invention and the fiber index performance; DETAILED DESCRIPTION

[0038] Embodiment 1:

[0039] A method for modifying the inner and outer surfaces of a silicone tube for a precision water pollution detector comprises the following stages:

[0040] S1: Raw material preparation

[0041] ① Raw material preparation: prepare sufficient commercial medical grade silicone hose, chitosan nitric acid aqueous solution with a chitosan mass fraction of 1%, C 26 H 42 N2O37 S5, C4H5NO3, C8H 18 ClN3, aniline, ammonium persulfate, 10% hydrochloric acid aqueous solution, nano-silicon dioxide, sodium chloride;

[0042] ② Preparation of auxiliary materials: prepare sufficient acetone, ethanol, deionized water, hydrogen peroxide, MES buffer with a pH value of 5.2-5.8, and sodium hydroxide aqueous solution with a solute mass fraction of 1%;

[0043] S2: Pre-preparation

[0044] ① The commercially available medical-grade silicone hose prepared in step ① of stage S1 is completely immersed in the acetone solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned; then it is completely immersed in the ethanol solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned; finally, it is completely immersed in the sodium hydroxide aqueous solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned, to obtain a clean micro-etched silicone tube;

[0045] ② The clean micro-etched silicone tube obtained in step ① is completely immersed in the hydrogen peroxide prepared in step ② of stage S1 for 70-80 minutes, then the treated clean silicone tube is taken out and completely immersed in the deionized water prepared in step ② of stage S1, and ultrasonic oscillation is used to clean the inner and outer surfaces of the tube to obtain a pretreated silicone tube;

[0046] ③ Place the pretreated silicone tube obtained in step ② in a drying electric oven and bake at a temperature of 55°C-75°C until the pretreated silicone tube is completely dried to obtain the silicone tube to be modified;

[0047] S3: Internal surface treatment

[0048] ① Mix the aniline prepared in step ① of stage S1 with the aqueous hydrochloric acid solution in a volume ratio of 1:25 and place in a glass container, place in an ice-water mixture bath and stir with electromagnetic stirring until the mixture is uniform, to obtain a mixed solution A;

[0049] ② Mix the nano-silicon dioxide prepared in step ① of stage S1 and the deionized water prepared in step ② of stage S1 to form a turbid liquid B in a mass ratio of 3:7;

[0050] ③ The turbid solution B obtained in step ② and the mixed solution A obtained in step ① were mixed at a volume ratio of 1:5 and stirred to obtain a mixed solution C;

[0051] ④ In stage S2, the mixed solution C obtained in step ③ is introduced into the silicone tube to be modified obtained in step ③ to obtain a reaction system;

[0052] ⑤ Place the reaction system obtained in step ④ in an ice-water mixture bath, add 3.08 times the mass of aniline added in step ① of the ammonium persulfate prepared in step S1 ① to the mixed solution C, and the reaction system begins to react on the inner surface of the silicone tube to be modified; react for 18 minutes, and after the reaction is completed, clean the inner and outer surfaces of the treated silicone tube to obtain an inner surface modified silicone tube;

[0053] S4: External surface treatment

[0054] ① Block both ends of the inner surface modified silicone tube obtained in step ⑤ of stage S3 to prevent the liquid from entering the interior of the tube, thereby obtaining a closed silicone tube;

[0055] ② The sealed silicone tube obtained in step ① is completely immersed in the MES buffer prepared in step ② of stage S1 for 3 hours, and then taken out and completely immersed in the chitosan nitric acid aqueous solution prepared in step ① of stage S1. The reaction system is placed in a water bath shaker for treatment. The reaction parameters are: temperature 30°C, stirring rate 135rpm, treatment time 20h, and a pre-treated tube is obtained after the reaction is completed;

[0056] ③ After cleaning the primary pretreatment tube obtained in step ② with deionized water, completely immerse it in the sodium hydroxide aqueous solution prepared in step ② of stage S1, and let it stand for 13 hours. After the treatment, take it out, clean it, and dry it to obtain a primary treatment tube;

[0057] ④Put the C prepared in step ① of stage S1 26 H 42 N2O 37 S5, sodium chloride, C4H5NO3, C8H 18 ClN3 was mixed evenly in a mass ratio of 328:4.2:1:3.4, and MES buffer was used as solvent to prepare a mixed solution D;

[0058] ⑤ Completely immerse the once treated tube obtained in step ③ in the MES buffer prepared in step ② of stage S1 for 3 hours, take it out and then completely immerse it in the mixed solution D prepared in step ④, place this reaction system in a water bath shaker for treatment, the reaction parameters are: temperature 30°C, stirring rate 135rpm, treatment time 20h, after the reaction is completed, obtain the outer surface treated tube, clean and dry it to obtain the required inner and outer surface modified silicone tube.

[0059] like Figure 1-3As shown, the silicone tube manufactured according to the method of this embodiment has a film thickness on the inner surface of the silicone tube between 40nm and 100nm, and a film contact angle of 117.1°-122.6° (the contact angle of the original silicone tube surface is about 80°). Compared with the original silicone, it has better hydrophobicity and corrosion resistance; tensile strength is 9.8MPa-10.7MPa, elongation at break is 570%-610%, tear strength is 24kN / m-27kN / m, and can withstand a long-term use temperature of 105°C and a maximum of 120°C, the same below.

[0060] Embodiment 2:

[0061] The whole is the same as Example 1, the difference is:

[0062] S3: Internal surface treatment

[0063] ① Mix the aniline prepared in step ① of stage S1 with the aqueous hydrochloric acid solution in a volume ratio of 1:24 and place in a glass container, place in an ice-water mixture bath and stir with electromagnetic stirring until the mixture is uniform, to obtain a mixed solution A;

[0064] ② Mix the nano-silicon dioxide prepared in step ① of stage S1 and the deionized water prepared in step ② of stage S1 to form a turbid liquid B in a mass ratio of 3:6.8;

[0065] ③ The turbid solution B obtained in step ② and the mixed solution A obtained in step ① were mixed at a volume ratio of 1:4.9 and stirred to obtain a mixed solution C;

[0066] ④ In stage S2, the mixed solution C obtained in step ③ is introduced into the silicone tube to be modified obtained in step ③ to obtain a reaction system;

[0067] ⑤ Place the reaction system obtained in step ④ in an ice-water mixture bath, add ammonium persulfate prepared in step S1① in an amount 3 times the mass of aniline added in step ① to the mixed solution C, and the reaction system begins to react on the inner surface of the silicone tube to be modified; react for 15 minutes, and after the reaction is completed, clean the inner and outer surfaces of the treated silicone tube to obtain an inner surface modified silicone tube;

[0068] S4: External surface treatment

[0069] ② The sealed silicone tube obtained in step ① is completely immersed in the MES buffer prepared in step ② of stage S1 for 2.5 hours, taken out and then completely immersed in the chitosan nitric acid aqueous solution prepared in step ① of stage S1, and the reaction system is placed in a water bath shaker for treatment. The reaction parameters are: temperature 28°C, stirring rate 120rpm, treatment time 18h, and a pre-treated tube is obtained after the reaction is completed;

[0070] ③ After cleaning the primary pretreatment tube obtained in step ② with deionized water, completely immerse it in the sodium hydroxide aqueous solution prepared in step ② of stage S1, and let it stand for 12 hours. After the treatment, take it out, clean it, and dry it to obtain a primary treatment tube;

[0071] ④Put the C prepared in step ① of stage S1 26 H 42 N2O 37 S5, sodium chloride, C4H5NO3, C8H 18 ClN3 was mixed evenly in a mass ratio of 325:4.1:1:3.3, and MES buffer was used as solvent to prepare a mixed solution D;

[0072] ⑤ Completely immerse the once treated tube obtained in step ③ in the MES buffer prepared in step ② of stage S1 for 2.5 hours, take it out and then completely immerse it in the mixed solution D prepared in step ④, place this reaction system in a water bath shaker for treatment, the reaction parameters are: temperature 28°C, stirring rate 120rpm, treatment time 18h, after the reaction is completed, obtain the outer surface treated tube, clean and dry it to obtain the required inner and outer surface modified silicone tube.

[0073] Embodiment 3:

[0074] The whole is the same as Example 1, except that:

[0075] S3: Internal surface treatment

[0076] ① Mix the aniline prepared in step ① of stage S1 with the aqueous hydrochloric acid solution in a volume ratio of 1:27) and place in a glass container, place in an ice-water mixture bath and stir with electromagnetic stirring until the mixture is uniform, to obtain a mixed solution A;

[0077] ② Mix the nano-silica prepared in step ① of stage S1 and the deionized water prepared in step ② of stage S1 to form a turbid liquid B in a mass ratio of 3:7.2;

[0078] ③ The turbid solution B obtained in step ② and the mixed solution A obtained in step ① were mixed at a volume ratio of 1:5.6 and stirred to obtain a mixed solution C;

[0079] ④ In stage S2, the mixed solution C obtained in step ③ is introduced into the silicone tube to be modified obtained in step ③ to obtain a reaction system;

[0080] ⑤ Place the reaction system obtained in step ④ in an ice-water mixture bath, add 3.1 times the mass of aniline added in step ① of the ammonium persulfate prepared in step S1 ① to the mixed solution C, and the reaction system begins to react on the inner surface of the silicone tube to be modified; react for 20 minutes, and after the reaction is completed, clean the inner and outer surfaces of the treated silicone tube to obtain an inner surface modified silicone tube;

[0081] S4: External surface treatment

[0082] ② The sealed silicone tube obtained in step ① is completely immersed in the MES buffer prepared in step ② of stage S1 for 3 hours, and then taken out and completely immersed in the chitosan nitric acid aqueous solution prepared in step ① of stage S1. The reaction system is placed in a water bath shaker for treatment. The reaction parameters are: temperature 35°C, stirring rate 150rpm, treatment time 22h, and a pre-treated tube is obtained after the reaction is completed;

[0083] ③ After cleaning the primary pretreatment tube obtained in step ② with deionized water, completely immerse it in the sodium hydroxide aqueous solution prepared in step ② of stage S1, and let it stand for 14 hours. After the treatment, take it out, clean it, and dry it to obtain a primary treatment tube;

[0084] ④Put the C prepared in step ① of stage S1 26 H 42 N2O 37 S5, sodium chloride, C4H5NO3, C8H 18 ClN3 was mixed evenly in a mass ratio of 330:4.4:1:3.5, and MES buffer was used as solvent to prepare a mixed solution D;

[0085] ⑤ Completely immerse the once treated tube obtained in step ③ in the MES buffer prepared in step ② of stage S1 for 3 hours, take it out and then completely immerse it in the mixed solution D prepared in step ④, place this reaction system in a water bath shaker for treatment, the reaction parameters are: temperature 35°C, stirring rate 150rpm, treatment time 22h, after the reaction is completed, obtain the outer surface treated tube, clean and dry it to obtain the required inner and outer surface modified silicone tube.

[0086] The above description of the disclosed embodiments is intended only to enable those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for modifying the inner and outer surfaces of a silicone tube for a precision water pollution detector, characterized in that The following phases are included: S1: Raw material preparation ① Raw material preparation: prepare sufficient commercially available medical grade silicone hose, chitosan nitric acid aqueous solution with a chitosan mass fraction of 1%, C 26 H 42 N2O 37 S5, C4H5NO3, C8H 18 ClN3, aniline, ammonium persulfate, 10% hydrochloric acid aqueous solution, nano-silicon dioxide, sodium chloride; ② Preparation of auxiliary materials: prepare sufficient acetone, ethanol, deionized water, hydrogen peroxide, MES buffer with a pH value of 5.2-5.8, and sodium hydroxide aqueous solution with a solute mass fraction of 1%; S2: Pre-preparation ① The commercially available medical-grade silicone hose prepared in step ① of stage S1 is completely immersed in the acetone solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned; then it is completely immersed in the ethanol solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned; finally, it is completely immersed in the sodium hydroxide aqueous solution prepared in step ② of stage S1, and is treated with ultrasonic oscillation until the inner and outer surfaces of the pipe are cleaned, so as to obtain a clean micro-etched silicone tube; ② The clean micro-etched silicone tube obtained in step ① is completely immersed in the hydrogen peroxide prepared in step ② of stage S1 for 70-80 minutes, then the treated clean silicone tube is taken out and completely immersed in the deionized water prepared in step ② of stage S1, and ultrasonic oscillation is used to clean the inner and outer surfaces of the tube to obtain a pretreated silicone tube; ③ Place the pretreated silicone tube obtained in step ② in a drying electric oven and bake at a temperature of 55°C-75°C until the pretreated silicone tube is completely dried to obtain the silicone tube to be modified; S3: Inner surface treatment ① Mix the aniline prepared in step ① of stage S1 with the aqueous hydrochloric acid solution in a volume ratio of 1:(24-27) and place in a glass container, place in an ice-water mixture bath and stir with electromagnetic stirring until the mixture is uniform, to obtain a mixed solution A; ② Mix the nano-silicon dioxide prepared in step ① of stage S1 and the deionized water prepared in step ② of stage S1 to form a turbid liquid B in a mass ratio of 3:(6.8-7.2); ③ Mix the turbid solution B obtained in step ② and the mixed solution A obtained in step ① at a volume ratio of 1:(4.9-5.6) and stir evenly to obtain a mixed solution C; ④ In stage S2, the mixed solution C obtained in step ③ is introduced into the silicone tube to be modified obtained in step ③ to obtain a reaction system; ⑤ Place the reaction system obtained in step ④ in an ice-water mixture bath, add 3 to 3.1 times the mass of aniline added in step ① of the ammonium persulfate prepared in step S1 ① to the mixed solution C, and the reaction system begins to react on the inner surface of the silicone tube to be modified; react for 15 min to 20 min, and after the reaction is completed, clean the inner and outer surfaces of the treated silicone tube to obtain an inner surface modified silicone tube; S4: External surface treatment ① Block both ends of the inner surface modified silicone tube obtained in step ⑤ of stage S3 to prevent the liquid from entering the interior of the tube, thereby obtaining a closed silicone tube; ② The sealed silicone tube obtained in step ① is completely immersed in the MES buffer prepared in step ② of stage S1 for 2.5h-3h, taken out and then completely immersed in the chitosan nitric acid aqueous solution prepared in step ① of stage S1, and the reaction system is placed in a water bath shaker for treatment. The reaction parameters are: temperature 28°C-35°C, stirring rate 120rpm-150rpm, treatment time 18h-22h, and a pre-treated tube is obtained after the reaction is completed; ③ After cleaning the primary pretreatment tube obtained in step ② with deionized water, completely immerse it in the sodium hydroxide aqueous solution prepared in step ② of stage S1, and let it stand for 12h-14h. After the treatment, take it out, clean it and dry it to obtain a primary treatment tube; ④Put the C prepared in step ① of stage S1 26 H 42 N2O 37 S5, sodium chloride, C4H5NO3, C8H 18 ClN3 is mixed uniformly in a mass ratio of (325-330):(4.1-4.4):1:(3.3-3.5), and MES buffer is used as a solvent to prepare a mixed solution D; ⑤ Completely immerse the once treated tube obtained in step ③ in the MES buffer prepared in step ② of stage S1 for 2.5h-3h, take it out and then completely immerse it in the mixed solution D prepared in step ④, place this reaction system in a water bath shaker for treatment, the reaction parameters are: temperature 28℃-35℃, stirring rate 120rpm-150rpm, treatment time 18h-22h, after the reaction is completed, obtain the outer surface treated tube, clean and dry it to obtain the required inner and outer surface modified silicone tube.

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