High-antibacterial silicone tube and preparation method thereof

Abstract

The invention discloses a highly antibacterial silicone tube and a preparation method thereof, and relates to the technical field of silicone tubes, white carbon black and a modified silicon dioxide-nano silver compound are added into the silicone tube as filler, and the mechanical property of the silicone tube is enhanced. The modified silicon dioxide-nano silver compound is modified by using a titanate coupling agent, so that the hydrophobicity of the silicone tube is enhanced, bacteria are not easy to attach to the surface of the silicone tube, and the antibacterial property of the silicone tube is improved. The surface of the silicone tube is also coated with a layer of antibacterial coating, and nano-silver-loaded polyethyleneimine is added into the antibacterial coating, so that the antibacterial performance of the silicone tube is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of silicone tubes, in particular to a highly antibacterial silicone tube and a preparation method thereof. Background Art

[0002] Although traditional silicone tubes have certain high temperature resistance, chemical corrosion resistance and flexibility, they are easily contaminated by microorganisms during use, leading to bacterial growth and potential infection risks. Therefore, in the medical and industrial fields, it is crucial to improve the antibacterial properties and biocompatibility of silicone tubes. To this end, the prior art introduces antibacterial agents or modifiers into silicone tubes to inhibit the growth of bacteria and other microorganisms, thereby enhancing their reliability and safety in medical equipment, food processing and other application environments with high hygiene requirements. However, the antibacterial properties of silicone tubes need to be further improved.

[0003] In order to solve the above problems and improve the antibacterial performance of silicone tubes, the present invention provides a highly antibacterial silicone tube and a preparation method thereof. Summary of the invention

[0004] The object of the present invention is to provide a highly antibacterial silicone tube and a preparation method thereof, so as to solve the problems raised in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for preparing a highly antibacterial silicone tube comprises the following steps:

[0007] Step 1: Take silver nitrate, polyethyleneimine complex, and N,N-dimethylformamide, stir evenly, heat to 65-70°C, stir for 8-10 hours, filter, wash, and dry to obtain polyethyleneimine loaded with nanosilver;

[0008] Step 2: Take epoxy resin, polyethyleneimine loaded with nanosilver, polydimethylsiloxane, and ethyl acetate, stir evenly, add dicyandiamide, and stir for 20-30 minutes to obtain an antibacterial coating;

[0009] Step 3: Take silicone rubber, polyvinylidene fluoride resin, hydroxy silicone oil, white carbon black, magnesium stearate, antioxidant, plasticizer, propylene oxide glycerol polyether, polymethyl triethoxy silane, mix, add titanium oxide, modified silica-nanosilver composite, continue mixing for 10-15 minutes, add vulcanizing agent, mix evenly, extrude, vulcanize and shape to obtain a silicone tube;

[0010] Step 4: Coat a layer of antibacterial coating on the surface of the silicone tube and dry it to obtain a highly antibacterial silicone tube.

[0011] More optimally, the silicone tube includes the following ingredients, calculated by weight: 110-120 parts of silicone rubber, 12-14 parts of polyvinylidene fluoride resin, 8-10 parts of hydroxy silicone oil, 6-9 parts of white carbon black, 15-17 parts of magnesium stearate, 4-6 parts of antioxidant, 5-7 parts of plasticizer, 15-16 parts of propylene oxide glycerol polyether, 16-20 parts of polymethyltriethoxysilane, 8-10 parts of titanium oxide, 3-4 parts of modified silica-nanosilver composite, and 6-8 parts of vulcanizing agent.

[0012] More optimally, in step one, the preparation method of the polyethyleneimine complex is: take dopamine hydrochloride, quaternized polyethyleneimine, and Tris-HCl buffer, stir evenly, add ferrosoferric oxide nanoparticles, ultrasonically disperse for 30-40 minutes, then stir for 6-8 hours, filter, wash, and dry to obtain the polyethyleneimine complex.

[0013] More optimally, the preparation method of the quaternized polyethyleneimine is: branched polyethyleneimine and deionized water are stirred evenly, cooled to 0-5°C, propylene oxide is added dropwise, stirred at 5°C for 10-14h, heated to 40-45°C, reacted for 1-2h, benzyl chloride is added, stirred at 45-50°C for 22-26h, filtered, washed, extracted, and distilled to obtain quaternized polyethyleneimine.

[0014] More optimally, the preparation method of the modified silica-nanosilver composite is: take ethanol and deionized water, stir evenly, add the silica-nanosilver composite, ultrasonically disperse for 1-2 hours, add a titanate coupling agent, drop acetic acid, adjust the pH value to 4, heat to 75-80°C and react for 4-5 hours, centrifuge, wash, filter, and dry to obtain the modified silica-nanosilver composite.

[0015] More optimally, the preparation method of the silica-nanosilver composite is: take sodium sulfate and deionized water, stir evenly to obtain a sodium sulfate solution; add a sodium silicate aqueous solution to the sodium sulfate solution, heat to 65-70°C, stir for 20-30 minutes, drip a sulfuric acid aqueous solution, adjust the pH value to 8.5, add dopamine hydrochloride, then drip a silver nitrate aqueous solution and sodium citrate, stir for 3-4 hours, then drip a sodium silicate aqueous solution, stir for 20-30 minutes, drip a sulfuric acid aqueous solution, adjust the pH value to 4.5, stir for 1-2 hours, filter, wash, and dry to obtain a silica-nanosilver composite.

[0016] More optimally, the vulcanizing agent is any one or more of benzoyl peroxide and 2,4-dichlorobenzoyl peroxide.

[0017] More optimally, the antioxidant is any one or more of antioxidant RD and antioxidant 4010; and the plasticizer is alkyl phenyl sulfonate.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The present invention adds white carbon black and modified silica-nanosilver composite to the silicone tube as fillers to enhance the mechanical properties of the silicone tube. The modified silica-nanosilver composite is modified by a titanate coupling agent to enhance the hydrophobicity of the silicone tube, making it difficult for bacteria to adhere to the surface of the silicone tube, thereby improving the antibacterial performance of the silicone tube.

[0020] 2. In order to further enhance the antibacterial properties of the silicone tube, the present invention applies a layer of antibacterial coating on the surface of the silicone tube. Polyethyleneimine loaded with nanosilver is added to the antibacterial coating. First, the polyethyleneimine is quaternized and a quaternized polyethyleneimine is prepared using benzyl chloride to improve the antibacterial properties of the polyethyleneimine. Then, the polyethyleneimine is compounded with ferrosoferric oxide nanoparticles by utilizing the adhesiveness of polydopamine, and then nanosilver is loaded on the surface of the polyethyleneimine composite, further improving the antibacterial properties of the silicone tube. At the same time, the amino groups on the polyethyleneimine loaded with nanosilver can react with the epoxy groups in the epoxy resin, thereby improving the dispersibility of the polyethyleneimine loaded with nanosilver in the coating, thereby further improving the antibacterial properties of the silicone tube. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] There is no special restriction on the purchase manufacturers and models of all raw materials involved in the present invention, and illustratively include: ferroferric oxide nanoparticles: particle size: 10-30nm; white carbon black: particle size: 20-50nm; titanium oxide: particle size: 20-30nm; titanate coupling agent: model: TM-2P; branched polyethyleneimine: can be purchased from Sigma-Aldrich, model: 408727; alkyl sulfonate phenyl ester: can be purchased from Shandong Kejian Chemical Co., Ltd., model: T-50; polyvinylidene fluoride resin: can be purchased from Shanghai San Ai Fu, model: FR901; epoxy resin: model: E44.

[0023] Embodiment 1: A method for preparing a highly antibacterial silicone tube, comprising the following steps:

[0024] Step 1: Preparation of silica-nanosilver composite:

[0025] Take 1g of sodium sulfate and 100mL of deionized water, stir evenly to obtain a sodium sulfate solution; add 75mL of a 2mol / L sodium silicate aqueous solution to the sodium sulfate solution, heat to 68°C, stir for 25min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 8.5, add 12g of dopamine hydrochloride, then drop 25mL of a 1.5mol / L silver nitrate aqueous solution and 3g of sodium citrate, stir for 3.5h, then drop 40mL of a 2mol / L sodium silicate aqueous solution, stir for 25min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 4.5, stir for 1.5h, filter, wash, and dry to obtain a silica-nanosilver composite;

[0026] Step 2: Preparation of modified silica-nanosilver composite:

[0027] Take 90 mL of ethanol and 10 mL of deionized water, stir evenly, add 4 g of silica-nanosilver composite, ultrasonically disperse for 1.5 h, add 0.3 g of titanate coupling agent, drop acetic acid, adjust the pH value to 4, heat to 78 ° C for 4.5 h, centrifuge, wash, filter, and dry to obtain a modified silica-nanosilver composite;

[0028] Step 3: Preparation of quaternized polyethyleneimine:

[0029] 1g branched polyethyleneimine and 30mL deionized water are stirred evenly, cooled to 2°C, 25g propylene oxide is added dropwise, stirred at 5°C for 12h, heated to 42°C, reacted for 1.5h, 12g benzyl chloride is added, stirred at 47°C for 24h, filtered, washed, extracted, and distilled to obtain quaternized polyethyleneimine;

[0030] Step 4: Preparation of polyethyleneimine loaded with nanosilver:

[0031] Take 1g dopamine hydrochloride, 1g quaternized polyethyleneimine, and 500mL Tris-HCl buffer with a pH value of 8.5, stir evenly, add 0.3g ferrosoferric oxide nanoparticles, ultrasonically disperse for 35min, then stir for 7h, filter, wash, and dry to obtain a polyethyleneimine complex;

[0032] Take 0.3g silver nitrate, 1g polyethyleneimine complex, 50mL N,N-dimethylformamide, stir evenly, heat to 68°C, stir for 9h, filter, wash, and dry to obtain polyethyleneimine loaded with nanosilver;

[0033] Step 5: Preparation of antibacterial coating:

[0034] Take 10g of epoxy resin, 1g of polyethyleneimine loaded with nanosilver, 2g of polydimethylsiloxane, and 80g of ethyl acetate, stir evenly, add 4g of dicyandiamide, and stir for 25min to obtain an antibacterial coating;

[0035] Step 6: Preparation of silicone tube:

[0036] Silicone rubber, polyvinylidene fluoride resin, hydroxy silicone oil, white carbon black, magnesium stearate, antioxidant, plasticizer, propylene oxide glycerol polyether, polymethyl triethoxy silane are mixed, titanium oxide and modified silicon dioxide-nanosilver composite are added, and the mixing is continued for 12 minutes, and a vulcanizing agent is added, and the mixing is uniform, extruded, and vulcanized to obtain a silicone tube;

[0037] The silicone tube comprises the following components, calculated by weight: 115 parts of silicone rubber, 13 parts of polyvinylidene fluoride resin, 9 parts of hydroxy silicone oil, 7 parts of white carbon black, 16 parts of magnesium stearate, 5 parts of antioxidant, 6 parts of plasticizer, 15.5 parts of propylene oxide glycerol polyether, 18 parts of polymethyl triethoxy silane, 9 parts of titanium oxide, 3.5 parts of modified silicon dioxide-nanosilver composite, and 7 parts of vulcanizing agent;

[0038] The plasticizer is alkyl sulfonate phenyl ester; the vulcanizing agent is benzoyl peroxide; the antioxidant is antioxidant RD;

[0039] A layer of antibacterial coating with a thickness of 5 μm is coated on the surface of the silicone tube and dried to obtain a highly antibacterial silicone tube.

[0040] Embodiment 2: A method for preparing a highly antibacterial silicone tube, comprising the following steps:

[0041] Step 1: Preparation of silica-nanosilver composite:

[0042] Take 1g of sodium sulfate and 100mL of deionized water, stir evenly to obtain a sodium sulfate solution; add 75mL of a 2mol / L sodium silicate aqueous solution to the sodium sulfate solution, heat to 65°C, stir for 20min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 8.5, add 12g of dopamine hydrochloride, then drop 25mL of a 1.5mol / L silver nitrate aqueous solution and 3g of sodium citrate, stir for 3h, then drop 40mL of a 2mol / L sodium silicate aqueous solution, stir for 20min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 4.5, stir for 1h, filter, wash, and dry to obtain a silica-nanosilver composite;

[0043] Step 2: Preparation of modified silica-nanosilver composite:

[0044] Take 90 mL of ethanol and 10 mL of deionized water, stir evenly, add 4 g of silica-nanosilver composite, ultrasonically disperse for 1 h, add 0.3 g of titanate coupling agent, drop acetic acid, adjust the pH value to 4, heat to 75 ° C for 4 h, centrifuge, wash, filter, and dry to obtain a modified silica-nanosilver composite;

[0045] Step 3: Preparation of quaternized polyethyleneimine:

[0046] 1g branched polyethyleneimine and 30mL deionized water are stirred evenly, cooled to 0°C, 25g propylene oxide is added dropwise, stirred at 5°C for 10h, heated to 40°C, reacted for 1h, 12g benzyl chloride is added, stirred at 45°C for 22h, filtered, washed, extracted, and distilled to obtain quaternized polyethyleneimine;

[0047] Step 4: Preparation of polyethyleneimine loaded with nanosilver:

[0048] Take 1g dopamine hydrochloride, 1g quaternized polyethyleneimine, and 500mL Tris-HCl buffer with a pH value of 8.5, stir evenly, add 0.3g ferrosoferric oxide nanoparticles, ultrasonically disperse for 30min, then stir for 6h, filter, wash, and dry to obtain a polyethyleneimine complex;

[0049] Take 0.3g silver nitrate, 1g polyethyleneimine complex, and 50mL N,N-dimethylformamide, stir evenly, heat to 65°C, stir for 8h, filter, wash, and dry to obtain polyethyleneimine loaded with nanosilver;

[0050] Step 5: Preparation of antibacterial coating:

[0051] Take 10g of epoxy resin, 1g of polyethyleneimine loaded with nanosilver, 2g of polydimethylsiloxane, and 80g of ethyl acetate, stir evenly, add 4g of dicyandiamide, and stir for 20min to obtain an antibacterial coating;

[0052] Step 6: Preparation of silicone tube:

[0053] Silicone rubber, polyvinylidene fluoride resin, hydroxy silicone oil, white carbon black, magnesium stearate, antioxidant, plasticizer, propylene oxide glycerol polyether, polymethyl triethoxy silane are mixed, titanium oxide and modified silicon dioxide-nanosilver composite are added, and the mixing is continued for 10 minutes, and a vulcanizing agent is added, and the mixing is uniform, extruded, and vulcanized to obtain a silicone tube;

[0054] The silicone tube comprises the following components, calculated by weight: 110 parts of silicone rubber, 12 parts of polyvinylidene fluoride resin, 8 parts of hydroxy silicone oil, 6 parts of white carbon black, 15 parts of magnesium stearate, 4 parts of antioxidant, 5 parts of plasticizer, 15 parts of propylene oxide glycerol polyether, 16 parts of polymethyl triethoxy silane, 8 parts of titanium oxide, 3 parts of modified silicon dioxide-nanosilver composite, and 6 parts of vulcanizing agent;

[0055] The plasticizer is alkyl sulfonate phenyl ester; the vulcanizing agent is 2,4-dichlorobenzoyl peroxide; the antioxidant is antioxidant 4010;

[0056] A layer of antibacterial coating with a thickness of 5 μm is coated on the surface of the silicone tube and dried to obtain a highly antibacterial silicone tube.

[0057] Embodiment 3: A method for preparing a highly antibacterial silicone tube, comprising the following steps:

[0058] Step 1: Preparation of silica-nanosilver composite:

[0059] Take 1g of sodium sulfate and 100mL of deionized water, stir evenly to obtain a sodium sulfate solution; add 75mL of a 2mol / L sodium silicate aqueous solution to the sodium sulfate solution, heat to 70°C, stir for 30min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 8.5, add 12g of dopamine hydrochloride, then drop 25mL of a 1.5mol / L silver nitrate aqueous solution and 3g of sodium citrate, stir for 4h, then drop 40mL of a 2mol / L sodium silicate aqueous solution, stir for 30min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 4.5, stir for 2h, filter, wash, and dry to obtain a silica-nanosilver composite;

[0060] Step 2: Preparation of modified silica-nanosilver composite:

[0061] Take 90 mL of ethanol and 10 mL of deionized water, stir evenly, add 4 g of silica-nanosilver composite, ultrasonically disperse for 2 h, add 0.3 g of titanate coupling agent, drop acetic acid, adjust the pH value to 4, heat to 80 ° C for 5 h, centrifuge, wash, filter, and dry to obtain a modified silica-nanosilver composite;

[0062] Step 3: Preparation of quaternized polyethyleneimine:

[0063] 1g branched polyethyleneimine and 30mL deionized water were stirred evenly, cooled to 5°C, 25g propylene oxide was added dropwise, stirred at 5°C for 14h, heated to 45°C, reacted for 2h, 12g benzyl chloride was added, stirred at 50°C for 26h, filtered, washed, extracted, and distilled to obtain quaternary polyethyleneimine;

[0064] Step 4: Preparation of polyethyleneimine loaded with nanosilver:

[0065] Take 1g dopamine hydrochloride, 1g quaternized polyethyleneimine, and 500mL Tris-HCl buffer with a pH value of 8.5, stir evenly, add 0.3g ferrosoferric oxide nanoparticles, ultrasonically disperse for 40min, then stir for 8h, filter, wash, and dry to obtain a polyethyleneimine complex;

[0066] Take 0.3g silver nitrate, 1g polyethyleneimine complex, 50mL N,N-dimethylformamide, stir evenly, heat to 70°C, stir for 10h, filter, wash, and dry to obtain polyethyleneimine loaded with nanosilver;

[0067] Step 5: Preparation of antibacterial coating:

[0068] Take 10g of epoxy resin, 1g of polyethyleneimine loaded with nanosilver, 2g of polydimethylsiloxane, and 80g of ethyl acetate, stir evenly, add 4g of dicyandiamide, and stir for 30min to obtain an antibacterial coating;

[0069] Step 6: Preparation of silicone tube:

[0070] Silicone rubber, polyvinylidene fluoride resin, hydroxy silicone oil, white carbon black, magnesium stearate, antioxidant, plasticizer, propylene oxide glycerol polyether, polymethyl triethoxy silane are mixed, titanium oxide and modified silicon dioxide-nanosilver composite are added, and the mixing is continued for 15 minutes, and a vulcanizing agent is added, and the mixing is uniform, extruded, and vulcanized to obtain a silicone tube;

[0071] The silicone tube comprises the following components, calculated by weight: 120 parts of silicone rubber, 14 parts of polyvinylidene fluoride resin, 10 parts of hydroxy silicone oil, 9 parts of white carbon black, 17 parts of magnesium stearate, 6 parts of antioxidant, 7 parts of plasticizer, 16 parts of propylene oxide glycerol polyether, 20 parts of polymethyl triethoxy silane, 10 parts of titanium oxide, 4 parts of modified silicon dioxide-nanosilver composite, and 8 parts of vulcanizing agent;

[0072] The plasticizer is alkyl sulfonate phenyl ester; the vulcanizing agent is 2,4-dichlorobenzoyl peroxide; the antioxidant is antioxidant 4010;

[0073] A layer of antibacterial coating with a thickness of 5 μm is coated on the surface of the silicone tube and dried to obtain a highly antibacterial silicone tube.

[0074] Comparative Example 1: The polyethyleneimine was not subjected to quaternization treatment, and the rest was the same as in Example 1:

[0075] Step 1: Preparation of silica-nanosilver composite:

[0076] Take 1g of sodium sulfate and 100mL of deionized water, stir evenly to obtain a sodium sulfate solution; add 75mL of a 2mol / L sodium silicate aqueous solution to the sodium sulfate solution, heat to 68°C, stir for 25min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 8.5, add 12g of dopamine hydrochloride, then drop 25mL of a 1.5mol / L silver nitrate aqueous solution and 3g of sodium citrate, stir for 3.5h, then drop 40mL of a 2mol / L sodium silicate aqueous solution, stir for 25min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 4.5, stir for 1.5h, filter, wash, and dry to obtain a silica-nanosilver composite;

[0077] Step 2: Preparation of modified silica-nanosilver composite:

[0078] Take 90 mL of ethanol and 10 mL of deionized water, stir evenly, add 4 g of silica-nanosilver composite, ultrasonically disperse for 1.5 h, add 0.3 g of titanate coupling agent, drop acetic acid, adjust the pH value to 4, heat to 78 ° C for 4.5 h, centrifuge, wash, filter, and dry to obtain a modified silica-nanosilver composite;

[0079] Step 3: Preparation of polyethyleneimine loaded with nanosilver:

[0080] Take 1g dopamine hydrochloride, 1g branched polyethyleneimine, and 500mL Tris-HCl buffer with a pH value of 8.5, stir evenly, add 0.3g ferrosoferric oxide nanoparticles, ultrasonically disperse for 35min, then stir for 7h, filter, wash, and dry to obtain a polyethyleneimine complex;

[0081] Take 0.3g silver nitrate, 1g polyethyleneimine complex, 50mL N,N-dimethylformamide, stir evenly, heat to 68°C, stir for 9h, filter, wash, and dry to obtain polyethyleneimine loaded with nanosilver;

[0082] Step 4: Preparation of antibacterial coating:

[0083] Take 10g of epoxy resin, 1g of polyethyleneimine loaded with nanosilver, 2g of polydimethylsiloxane, and 80g of ethyl acetate, stir evenly, add 4g of dicyandiamide, and stir for 25min to obtain an antibacterial coating;

[0084] Step 5: Preparation of silicone tube:

[0085] Silicone rubber, polyvinylidene fluoride resin, hydroxy silicone oil, white carbon black, magnesium stearate, antioxidant, plasticizer, propylene oxide glycerol polyether, polymethyl triethoxy silane are mixed, titanium oxide and modified silicon dioxide-nanosilver composite are added, and the mixing is continued for 12 minutes, and a vulcanizing agent is added, and the mixing is uniform, extruded, and vulcanized to obtain a silicone tube;

[0086] The silicone tube comprises the following components, calculated by weight: 115 parts of silicone rubber, 13 parts of polyvinylidene fluoride resin, 9 parts of hydroxy silicone oil, 7 parts of white carbon black, 16 parts of magnesium stearate, 5 parts of antioxidant, 6 parts of plasticizer, 15.5 parts of propylene oxide glycerol polyether, 18 parts of polymethyl triethoxy silane, 9 parts of titanium oxide, 3.5 parts of modified silicon dioxide-nanosilver composite, and 7 parts of vulcanizing agent;

[0087] The plasticizer is alkyl sulfonate phenyl ester; the vulcanizing agent is benzoyl peroxide; the antioxidant is antioxidant RD;

[0088] A layer of antibacterial coating with a thickness of 5 μm is coated on the surface of the silicone tube and dried to obtain a highly antibacterial silicone tube.

[0089] Comparative Example 2: No antibacterial coating was applied, and the rest was the same as Example 1:

[0090] Step 1: Preparation of silica-nanosilver composite:

[0091] Take 1g of sodium sulfate and 100mL of deionized water, stir evenly to obtain a sodium sulfate solution; add 75mL of a 2mol / L sodium silicate aqueous solution to the sodium sulfate solution, heat to 68°C, stir for 25min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 8.5, add 12g of dopamine hydrochloride, then drop 25mL of a 1.5mol / L silver nitrate aqueous solution and 3g of sodium citrate, stir for 3.5h, then drop 40mL of a 2mol / L sodium silicate aqueous solution, stir for 25min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 4.5, stir for 1.5h, filter, wash, and dry to obtain a silica-nanosilver composite;

[0092] Step 2: Preparation of modified silica-nanosilver composite:

[0093] Take 90 mL of ethanol and 10 mL of deionized water, stir evenly, add 4 g of silica-nanosilver composite, ultrasonically disperse for 1.5 h, add 0.3 g of titanate coupling agent, drop acetic acid, adjust the pH value to 4, heat to 78 ° C for 4.5 h, centrifuge, wash, filter, and dry to obtain a modified silica-nanosilver composite;

[0094] Step 3: Preparation of high antibacterial silicone tube:

[0095] Silicone rubber, polyvinylidene fluoride resin, hydroxy silicone oil, white carbon black, magnesium stearate, antioxidant, plasticizer, propylene oxide glycerol polyether, polymethyl triethoxy silane are mixed, titanium oxide and modified silicon dioxide-nanosilver composite are added, and the mixing is continued for 12 minutes, and a vulcanizing agent is added, and the mixing is uniform, extruded, and vulcanized to obtain a highly antibacterial silicone tube;

[0096] The highly antibacterial silicone tube comprises the following components, calculated by weight: 115 parts of silicone rubber, 13 parts of polyvinylidene fluoride resin, 9 parts of hydroxy silicone oil, 7 parts of white carbon black, 16 parts of magnesium stearate, 5 parts of antioxidant, 6 parts of plasticizer, 15.5 parts of propylene oxide glycerol polyether, 18 parts of polymethyl triethoxy silane, 9 parts of titanium oxide, 3.5 parts of modified silicon dioxide-nanosilver composite, and 7 parts of vulcanizing agent;

[0097] The plasticizer is alkyl sulfonate phenyl ester; the vulcanizing agent is benzoyl peroxide; and the antioxidant is antioxidant RD.

[0098] Comparative Example 3: No nanosilver is loaded on polyethyleneimine, and the rest is the same as Example 1:

[0099] Step 1: Preparation of silica-nanosilver composite:

[0100] Take 1g of sodium sulfate and 100mL of deionized water, stir evenly to obtain a sodium sulfate solution; add 75mL of a 2mol / L sodium silicate aqueous solution to the sodium sulfate solution, heat to 68°C, stir for 25min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 8.5, add 12g of dopamine hydrochloride, then drop 25mL of a 1.5mol / L silver nitrate aqueous solution and 3g of sodium citrate, stir for 3.5h, then drop 40mL of a 2mol / L sodium silicate aqueous solution, stir for 25min, drop a 2mol / L sulfuric acid aqueous solution, adjust the pH value to 4.5, stir for 1.5h, filter, wash, and dry to obtain a silica-nanosilver composite;

[0101] Step 2: Preparation of modified silica-nanosilver composite:

[0102] Take 90 mL of ethanol and 10 mL of deionized water, stir evenly, add 4 g of silica-nanosilver composite, ultrasonically disperse for 1.5 h, add 0.3 g of titanate coupling agent, drop acetic acid, adjust the pH value to 4, heat to 78 ° C for 4.5 h, centrifuge, wash, filter, and dry to obtain a modified silica-nanosilver composite;

[0103] Step 3: Preparation of quaternized polyethyleneimine:

[0104] 1g branched polyethyleneimine and 30mL deionized water are stirred evenly, cooled to 2°C, 25g propylene oxide is added dropwise, stirred at 5°C for 12h, heated to 42°C, reacted for 1.5h, 12g benzyl chloride is added, stirred at 47°C for 24h, filtered, washed, extracted, and distilled to obtain quaternized polyethyleneimine;

[0105] Step 4: Preparation of antibacterial coating:

[0106] Take 10g of epoxy resin, 1g of quaternized polyethyleneimine, 2g of polydimethylsiloxane, and 80g of ethyl acetate, stir evenly, add 4g of dicyandiamide, and stir for 25min to obtain an antibacterial coating;

[0107] Step 5: Preparation of silicone tube:

[0108] Silicone rubber, polyvinylidene fluoride resin, hydroxy silicone oil, white carbon black, magnesium stearate, antioxidant, plasticizer, propylene oxide glycerol polyether, polymethyl triethoxy silane are mixed, titanium oxide and modified silicon dioxide-nanosilver composite are added, and the mixing is continued for 12 minutes, and a vulcanizing agent is added, and the mixing is uniform, extruded, and vulcanized to obtain a silicone tube;

[0109] The silicone tube comprises the following components, calculated by weight: 115 parts of silicone rubber, 13 parts of polyvinylidene fluoride resin, 9 parts of hydroxy silicone oil, 7 parts of white carbon black, 16 parts of magnesium stearate, 5 parts of antioxidant, 6 parts of plasticizer, 15.5 parts of propylene oxide glycerol polyether, 18 parts of polymethyl triethoxy silane, 9 parts of titanium oxide, 3.5 parts of modified silicon dioxide-nanosilver composite, and 7 parts of vulcanizing agent;

[0110] The plasticizer is alkyl sulfonate phenyl ester; the vulcanizing agent is benzoyl peroxide; the antioxidant is antioxidant RD;

[0111] A layer of antibacterial coating with a thickness of 5 μm is coated on the surface of the silicone tube and dried to obtain a highly antibacterial silicone tube.

[0112] experiment

[0113] The performance of the highly antibacterial silicone tubes prepared in Examples 1 to 3 and Comparative Examples 1 to 3 was tested. The diameter of the silicone tube was 25 mm and the wall thickness was 1 mm. The tensile strength was tested. Staphylococcus aureus was prepared at a concentration of 10 7 CFU / mL bacterial suspension, take 100 μL of bacterial suspension and evenly coat it on LB solid culture medium, cut the highly antibacterial silicone tube into a disc with a diameter of 0.5 cm, place the disc in the culture medium, culture it at 37°C for 12 hours, test its antibacterial rate, and the data obtained are as follows:

[0114] Tensile strength / MPa Antibacterial rate / % Example 1 8.4 100 Example 2 8.3 100 Example 3 8.4 100 Comparative Example 1 8.4 99.2 Comparative Example 2 8.3 97.5 Comparative Example 3 8.0 98.8

[0115] Conclusion: From the comparison of the data in the table, it can be seen that in Comparative Example 1, polyethyleneimine is not quaternized, and the antibacterial rate decreases. Comparative Example 2 is not coated with antibacterial coating, and the antibacterial effect of the silicone tube is the worst at this time. Comparative Example 3 does not load nanosilver on polyethyleneimine, and the antibacterial performance of the silicone tube decreases to 98.8%. The high antibacterial silicone tube prepared in Examples 1-3 of the present invention has high tensile strength and good antibacterial performance. The present invention coats a layer of antibacterial coating on the surface of the silicone tube. Polyethyleneimine loaded with nanosilver is added to the antibacterial coating, firstly, polyethyleneimine is quaternized, and then, polyethyleneimine and ferrous oxide nanoparticles are compounded together by utilizing the adhesiveness of polydopamine, and then nanosilver is loaded on the surface of the polyethyleneimine complex, further improving the antibacterial performance of the silicone tube. At the same time, the amino group on the polyethyleneimine loaded with nanosilver can react with the epoxy group in the epoxy resin, thereby improving the dispersibility of the polyethyleneimine loaded with nanosilver in the coating, thereby further improving the antibacterial performance of the silicone tube.

[0116] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

Claims

1. A method for preparing a highly antibacterial silicone tube, characterized in that: The following steps are involved: Step 1: Take silver nitrate, polyethyleneimine complex, and N,N-dimethylformamide, stir evenly, heat to 65-70°C, stir for 8-10 hours, filter, wash, and dry to obtain polyethyleneimine loaded with nanosilver; Step 2: Take epoxy resin, polyethyleneimine loaded with nanosilver, polydimethylsiloxane, and ethyl acetate, stir evenly, add dicyandiamide, and stir for 20-30 minutes to obtain an antibacterial coating; Step 3: Take silicone rubber, polyvinylidene fluoride resin, hydroxy silicone oil, white carbon black, magnesium stearate, antioxidant, plasticizer, propylene oxide glycerol polyether, polymethyl triethoxy silane, mix, add titanium oxide, modified silica-nanosilver composite, continue mixing for 10-15 minutes, add vulcanizing agent, mix evenly, extrude, vulcanize and shape to obtain a silicone tube; Step 4: Coat a layer of antibacterial coating on the surface of the silicone tube and dry it to obtain a highly antibacterial silicone tube.

2. The method for preparing a highly antibacterial silicone tube according to claim 1, characterized in that: The silicone tube includes the following components, calculated by weight: 110-120 parts of silicone rubber, 12-14 parts of polyvinylidene fluoride resin, 8-10 parts of hydroxy silicone oil, 6-9 parts of white carbon black, 15-17 parts of magnesium stearate, 4-6 parts of antioxidant, 5-7 parts of plasticizer, 15-16 parts of propylene oxide glycerol polyether, 16-20 parts of polymethyltriethoxysilane, 8-10 parts of titanium oxide, 3-4 parts of modified silicon dioxide-nanosilver composite, and 6-8 parts of vulcanizing agent.

3. The method for preparing a highly antibacterial silicone tube according to claim 1, characterized in that: In step 1, the preparation method of the polyethyleneimine complex is as follows: take dopamine hydrochloride, quaternized polyethyleneimine, and Tris-HCl buffer, stir evenly, add ferrosoferric oxide nanoparticles, ultrasonically disperse for 30-40 minutes, then stir for 6-8 hours, filter, wash, and dry to obtain the polyethyleneimine complex.

4. The method for preparing a highly antibacterial silicone tube according to claim 3, characterized in that: The preparation method of the quaternary polyethyleneimine comprises: branched polyethyleneimine and deionized water, stirring evenly, cooling to 0-5°C, adding propylene oxide dropwise, stirring at 5°C for 10-14h, heating to 40-45°C, reacting for 1-2h, adding benzyl chloride, stirring at 45-50°C for 22-26h, filtering, washing, extracting, and distilling to obtain the quaternary polyethyleneimine.

5. The method for preparing a highly antibacterial silicone tube according to claim 1, characterized in that: The preparation method of the modified silicon dioxide-nanosilver composite is as follows: ethanol and deionized water are taken, stirred evenly, the silicon dioxide-nanosilver composite is added, ultrasonic dispersion is performed for 1-2 hours, a titanate coupling agent is added, acetic acid is added dropwise, the pH value is adjusted to 4, the temperature is raised to 75-80° C., the reaction is performed for 4-5 hours, centrifugation is performed, washing is performed, filtering is performed, and drying is performed to obtain the modified silicon dioxide-nanosilver composite.

6. The method for preparing a highly antibacterial silicone tube according to claim 5, characterized in that: The preparation method of the silicon dioxide-nanosilver composite comprises the following steps: taking sodium sulfate and deionized water, stirring evenly to obtain a sodium sulfate solution; adding a sodium silicate aqueous solution to the sodium sulfate solution, heating to 65-70° C., stirring for 20-30 minutes, dripping a sulfuric acid aqueous solution, adjusting the pH value to 8.5, adding dopamine hydrochloride, then dripping a silver nitrate aqueous solution and sodium citrate, stirring for 3-4 hours, then dripping a sodium silicate aqueous solution, stirring for 20-30 minutes, dripping a sulfuric acid aqueous solution, adjusting the pH value to 4.5, stirring for 1-2 hours, filtering, washing, and drying to obtain the silicon dioxide-nanosilver composite.

7. The method for preparing a highly antibacterial silicone tube according to claim 1, characterized in that: The vulcanizing agent is any one or more of benzoyl peroxide and 2,4-dichlorobenzoyl peroxide.

8. The method for preparing a highly antibacterial silicone tube according to claim 1, characterized in that: The antioxidant is any one or more of antioxidant RD and antioxidant 4010; the plasticizer is alkyl phenyl sulfonate.

9. A highly antibacterial silicone tube prepared according to the method for preparing a highly antibacterial silicone tube according to any one of claims 1 to 8.