Silicone rubber and preparation method thereof

Abstract

The invention discloses silicone rubber and a preparation method, and relates to the technical field of organic silicon. The silicone rubber disclosed by the invention is prepared from the following raw materials: phenyl hydrogen-containing polydimethylsiloxane, silicon resin, an ethylene-tetrafluoroethylene copolymer, epoxy polymethylphenyl siloxane, polyether modified polysiloxane and modified fumed silica. According to the silicone rubber disclosed by the invention, a cross-linked network formed by phenyl hydrogen-containing polydimethylsiloxane and epoxy polymethylphenyl siloxane is used as a matrix and is matched with the silicon resin and the modified fumed silica, and the roughness of the fumed silica and the low surface energy of an organic silicon material are combined, so that the surface of the silicone rubber has relatively strong hydrophobic performance; therefore, biological adhesion is effectively prevented, and a sustainable antibacterial effect is achieved.

Description

Technical Field

[0001] This invention relates to the field of organosilicon technology, and in particular to a silicone rubber and its preparation method. Background Technology

[0002] Silicone rubber molecules are low in polarity, resistant to high temperatures, and resistant to aging. It also exhibits good biocompatibility and anticoagulant properties, making it widely used in biological and medical fields. Existing technology discloses a method for antibacterial treatment of the surface of products made of silicone rubber. This method modifies the surface of the silicone rubber product by treating it under high-frequency electromagnetic radiation and low-temperature oxygen plasma, forming an antibacterial coating on the surface and thus improving its antibacterial properties. However, surface modification involves a large amount of work and is prone to degradation of antibacterial properties. Bulk-modified antibacterial materials can overcome the drawbacks of secondary surface modification and offer more durable antibacterial performance, but often require the addition of metal ions, which can affect the appearance of the silicone rubber. In particular, the addition of silver ions darkens the color of the silicone rubber, affecting its visual appeal. Summary of the Invention

[0003] The main objective of this invention is to develop an antibacterial silicone rubber that also possesses good and sustained antibacterial properties.

[0004] To achieve the above objectives, the present invention provides a silicone rubber comprising the following raw materials in parts by weight: phenyl hydrogen-containing polydimethylsiloxane: 50-80 parts; silicone resin: 3-15 parts; ethylene-tetrafluoroethylene copolymer: 20-40 parts; epoxy-based polymethylphenylsiloxane: 10-30 parts; polyether-modified polysiloxane: 5-15 parts; fumed silica: 5-10 parts; low-density polyethylene: 20-30 parts; lubricant: 0.8-2 parts; initiator: 0.6-1.6 parts; wherein the raw material of the silicone resin includes 3-aminophenylboronic acid.

[0005] In one embodiment, the fumed silica is fumed silica grafted with a mercaptosilane coupling agent.

[0006] In one embodiment, during the preparation of the fumed silica grafted with the mercaptosilane coupling agent, the weight ratio of the mercaptosilane coupling agent to the fumed silica is (10~50):(80~100).

[0007] In one embodiment, the phenyl hydrogen-containing polydimethylsiloxane has a viscosity of 600 cSt to 800 cSt, a phenyl content of 12 wt% to 15 wt%, and a hydrogen content of 0.3 wt% to 0.6 wt%.

[0008] In one embodiment, the viscosity of the polyether-modified polysiloxane is 30 cSt to 70 cSt; and the polyether-modified polysiloxane is synthesized from ethylene oxide and propylene oxide.

[0009] In one embodiment, the raw materials of the silicone resin include 3-aminophenylboronic acid and tetraethyl orthosilicate in a weight ratio of (50-150):(40-80).

[0010] In one embodiment, the raw materials of the silicone resin include 3-aminophenylboronic acid, tetraethyl orthosilicate and gallic acid in a weight ratio of (50~150):(40~80):(18~35).

[0011] In one embodiment, the silicone rubber comprises the following raw materials in parts by weight: phenyl hydrogen-containing polydimethylsiloxane: 60-70 parts; silicone resin: 5-10 parts; ethylene-tetrafluoroethylene copolymer: 20-30 parts; epoxy-based polymethylphenylsiloxane: 10-30 parts; polyether-modified polysiloxane: 5-15 parts; fumed silica: 6-8 parts; low-density polyethylene: 20-30 parts; lubricant: 0.8-2 parts; initiator: 0.6-1.6 parts.

[0012] The present invention also proposes a method for preparing the aforementioned silicone rubber, comprising the following steps: S1. Add polyether-modified polysiloxane and phenyl hydrogen-containing polydimethylsiloxane to a reaction vessel according to the ratio, stir and react at 60℃~70℃, then add ethylene-tetrafluoroethylene copolymer, epoxy-based polymethylphenylsiloxane, low-density polyethylene, lubricant, initiator, fumed silica and silicone resin and mix evenly to obtain a premix. S2. The premix obtained in step S1 is loaded into a mold for casting and subjected to ultraviolet irradiation treatment to obtain silicone rubber.

[0013] In one embodiment, during step S2, the ultraviolet irradiation wavelength is 100nm~200nm; the irradiation intensity is 1mW / cm². 2 ~100mW / cm 2 Irradiation time: 30s~300s.

[0014] The silicone rubber designed in this invention uses phenyl hydrogen-containing polydimethylsiloxane, epoxy-based polymethylphenylsiloxane, and silicone resin to form a polysiloxane crosslinking network. Then, nano-sized fumed silica grafted and modified with a mercaptosilane coupling agent is added to it. The mercapto-olefin click reaction is used to integrate the nanoparticles into the polysiloxane crosslinking network, increasing the compatibility between the nanoparticles and the polysiloxane crosslinking network. The combination of the roughness of the nanoparticles and the low surface energy of the polysiloxane crosslinking network gives the antibacterial silicone rubber surface superhydrophobic properties, thereby effectively preventing bioadhesion and achieving a continuous antibacterial effect. Detailed Implementation

[0015] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0016] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0017] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0018] The technical problem addressed by this application is that silicone rubber molecules have low polarity, high temperature resistance, and aging resistance, as well as good biocompatibility and anticoagulant properties, making it widely used in the biological and medical fields. Existing technology discloses a method for antibacterial treatment of the surface of products made of silicone rubber materials. This method modifies the surface of the silicone rubber product by treatment under high-frequency electromagnetic radiation and low-temperature oxygen plasma, forming an antibacterial coating on the surface of the silicone rubber product, thereby improving its antibacterial properties. However, surface modification involves a large amount of work and is prone to degradation of antibacterial properties. Bulk-modified antibacterial materials can overcome the disadvantages of secondary surface modification and have more durable antibacterial properties, but often require the addition of metal ions, which affects the appearance of the antibacterial silicone rubber. In particular, the addition of silver ions causes the antibacterial silicone rubber to turn brownish, affecting its visual appeal.

[0019] To address the aforementioned technical issues, an antibacterial silicone rubber with both good sustained antibacterial properties and low surface energy was designed.

[0020] This invention provides a silicone rubber comprising the following raw materials in parts by weight: Phenyl hydrogen-containing polydimethylsiloxane: 50-80 parts; silicone resin: 3-15 parts; ethylene-tetrafluoroethylene copolymer: 20-40 parts; epoxy-based polymethylphenylsiloxane: 10-30 parts; polyether-modified polysiloxane: 5-15 parts; fumed silica: 5-10 parts; low-density polyethylene: 20-30 parts; lubricant: 0.8-2 parts; initiator: 0.6-1.6 parts; the raw material of the silicone resin includes 3-aminophenylboronic acid.

[0021] It should be noted that the active groups in the silicone resin of this invention can undergo cross-linking reactions with the active groups on the surface of modified fumed silica and epoxy-based polymethylphenylsiloxane, thereby increasing the photocuring cross-linking reaction rate and shortening the molding time of the antibacterial silicone rubber. 3-Aminophenylboronic acid can act as a dynamic cross-linking point, forming reversible cross-links within the coating, endowing the material with self-healing capabilities (boronate bond recombination after damage) and stress dissipation capabilities (bond breakage and energy absorption under stress). Furthermore, the phenylboronic acid groups achieve contact antibacterial effects by disrupting microbial cell membranes or interfering with metabolic pathways (such as binding bacterial cell wall polysaccharides), exhibiting strong antibacterial activity.

[0022] It should also be noted that the weight ratio of phenyl hydrogen-containing polydimethylsiloxane and epoxy-based polymethylphenylsiloxane in this invention needs to be within a suitable range. If it is too high or too low, it will affect the photocuring film formation and the mechanical properties of the final antibacterial silicone rubber. If the amount of silicone resin added is too low, it will reduce the antibacterial properties of the antibacterial silicone rubber, while if the amount added is too high, it will affect the photocuring film formation. If the amount of modified nanoparticles added is too high, it will affect the photocuring effect, while if the amount added is too low, it will affect the hydrophobic effect of the antibacterial silicone rubber.

[0023] It should also be noted that the silicone rubber further includes initiators, specifically free radical photoinitiators and cationic photoinitiators; wherein, the free radical photoinitiator can be at least one of α,α-diethoxyacetophenone, α,α-dimethoxy-α-phenylacetophenone, 1-hydroxy-cyclohexylbenzophenone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-hydroxy-4-(2-hydroxyethoxy)-2-methylphenylpropanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2,4,6-trimethylbenzoyl-ethoxy-phenylphosphine oxide, and isopropylthioxanthracene; the cationic photoinitiator can be at least one of diaryliodothionium salt and triarylthionium salt.

[0024] In one embodiment, the fumed silica is fumed silica grafted with a mercaptosilane coupling agent.

[0025] In one embodiment, the particle size of the fumed silica is 10 nm to 50 nm.

[0026] It should be noted that the roughness of fumed silica combined with the low surface energy of the polysiloxane crosslinking network gives the antibacterial silicone rubber surface superhydrophobic properties, effectively preventing bioadhesion and achieving a sustained antibacterial effect. However, if the particle size of fumed silica is too small, it is not conducive to its uniform dispersion in polysiloxanes.

[0027] In one embodiment, during the preparation of the fumed silica grafted with the mercaptosilane coupling agent, the weight ratio of the mercaptosilane coupling agent to the fumed silica is (10~50):(80~100).

[0028] It is foreseeable that when a large amount of mercaptosilane coupling agent is added, it will easily lead to the aggregation of modified nanoparticles, thus reducing their dispersibility; when a small amount of mercaptosilane coupling agent is added, it will reduce the compatibility between modified nanoparticles and phenyl hydrogen-containing polydimethylsiloxane, epoxy-based polymethylphenylsiloxane, and silicone resin.

[0029] In one embodiment, the raw material of the silicone resin includes 3-aminophenylboronic acid. Further, the raw material of the silicone resin includes 3-aminophenylboronic acid and tetraethyl orthosilicate in a weight ratio of (50-150):(40-80).

[0030] It should be noted that the silicone resin of this invention undergoes a crosslinking reaction with modified fumed silica and epoxy-based polymethylphenylsiloxane, thereby increasing the photocuring crosslinking reaction rate and shortening the molding time of the antibacterial silicone rubber. It should also be noted that the introduction of 3-aminophenylboronic acid is mainly based on the unique dual function of its amino and phenylboronic acid groups, and cannot directly initiate free radical reactions. However, its amino group promotes silanol condensation and hydrosilylation reactions under heating conditions. Furthermore, 3-aminophenylboronic acid can act as a dynamic crosslinking point, forming reversible crosslinks within the coating, endowing the material with self-healing capabilities (boronic acid ester bond recombination after damage) and stress dissipation capabilities (bond breakage and energy absorption under stress). In addition, phenylboronic acid achieves contact antibacterial effects by disrupting microbial cell membranes or interfering with metabolic pathways (such as binding bacterial cell wall polysaccharides), exhibiting strong antibacterial activity.

[0031] In a preferred embodiment, the raw materials of the silicone resin include 3-aminophenylboronic acid, tetraethyl orthosilicate and gallic acid in a weight ratio of (50~150):(40~80):(18~35).

[0032] It should be noted that, based on the above embodiments, this embodiment further combines 3-aminophenylboronic acid with gallic acid during the preparation of silicone resin. The ortho-hydroxyl group of gallic acid can react with the boric acid group of 3-aminophenylboronic acid, and the borate ester complex is stably combined in a neutral environment without releasing 3-aminophenylboronic acid. In a weakly acidic environment containing bacteria, the borate ester complex decomposes to generate 3-aminophenylboronic acid and gallic acid, thereby regulating the release of antibacterial components in silicone rubber to a certain extent, thus achieving a better antibacterial effect.

[0033] Furthermore, the silicone resin of the present invention can be prepared by hydrolysis-condensation reaction of 3-aminophenylboronic acid and tetraethyl orthosilicate, wherein the pH of the hydrolysis-condensation reaction is 3 to 6.

[0034] It should be noted that if the pH of the hydrolysis-condensation reaction is too low or too high, it will lead to excessive cross-linking, resulting in poor compatibility between the silicone resin and phenyl hydrogen-containing polydimethylsiloxane and epoxy-based polymethylphenylsiloxane, thereby affecting the photocuring effect of the system.

[0035] In a specific embodiment, the mercaptosilane coupling agent of the present invention can be one or more of 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldiethoxysilane, and 3-mercaptopropylmethyldimethoxysilane; fumed silica can also be replaced by inorganic nanoparticles such as nano-titanium dioxide and nano-zirconia.

[0036] In one specific embodiment, the modified fumed silica of the present invention can be prepared by reacting fumed silica with a mercaptosilane coupling agent at 60°C to 80°C for 1 to 3 hours.

[0037] In one embodiment, the phenyl hydrogen-containing polydimethylsiloxane has a viscosity of 600 cSt to 800 cSt, a phenyl content of 12 wt% to 15 wt%, and a hydrogen content of 0.3 wt% to 0.6 wt%.

[0038] It should be noted that the phenyl-containing hydrogen polydimethylsiloxane in this application has a moderate viscosity, making it suitable for coating or use as a base polymer; it also possesses low surface tension, good electrical insulation, and hydrophobicity. The addition of phenyl groups may further enhance these properties, especially high-temperature resistance. The hydrogen content may involve the presence of silane-hydrogen bonds, which are typically used in subsequent addition reactions, such as hydrosilylation. Therefore, this material may be used as a crosslinking agent or reaction intermediate.

[0039] In one embodiment, the viscosity of the polyether-modified polysiloxane is 30 cSt to 70 cSt; and the polyether-modified polysiloxane is synthesized from ethylene oxide and propylene oxide.

[0040] In a preferred embodiment, the silicone rubber comprises the following raw materials in parts by weight: phenyl hydrogen-containing polydimethylsiloxane: 60-70 parts; silicone resin: 5-10 parts; ethylene-tetrafluoroethylene copolymer: 20-30 parts; epoxy-based polymethylphenylsiloxane: 10-30 parts; polyether-modified polysiloxane: 5-15 parts; fumed silica: 6-8 parts; low-density polyethylene: 20-30 parts; lubricant: 0.8-2 parts; initiator: 0.6-1.6 parts.

[0041] In a preferred embodiment, the fumed silica of the silicone rubber can be partially replaced with a mixed powder of nano-zeolite powder and nano-cerium oxide, wherein the amount of the mixed powder is 2 to 3 parts by weight, and the weight ratio of nano-zeolite powder to nano-cerium oxide in the mixed powder is (2 to 5): (1 to 2).

[0042] It should be noted that nano-cerium oxide has good UV resistance and exhibits good catalytic activity under light, which can decompose organic dirt adhering to the surface of silicone rubber. Nano-zeolite powder has good adsorption and slow release effects. The addition of these two nanoparticles, in synergy with the low surface energy of silicone resin, can make the surface of silicone rubber more hydrophobic by constructing a micro-nano rough structure, making it difficult for water droplets to adhere and making it harder for dirt and bacteria to remain.

[0043] The present invention also proposes a method for preparing the aforementioned silicone rubber, comprising the following steps: S1. Add polyether-modified polysiloxane and phenyl hydrogen-containing polydimethylsiloxane to a reaction vessel according to the ratio, stir and react at 60℃~70℃, then add ethylene-tetrafluoroethylene copolymer, epoxy-based polymethylphenylsiloxane, low-density polyethylene, lubricant, initiator, fumed silica and silicone resin and mix evenly to obtain a premix. S2. The premix obtained in step S1 is loaded into a mold for casting and subjected to ultraviolet irradiation treatment to obtain silicone rubber.

[0044] In one embodiment, during step S2, the irradiation wavelength is 100nm~200nm; the irradiation intensity is 1mW / cm2~100mW / cm2; and the irradiation time is 30s~300s.

[0045] The sources of raw materials in the embodiments of this invention are as follows: Phenyl hydrogen-containing polydimethylsiloxane: purchased from Dow Corning, product number DOWSIL™ H-25Resin.

[0046] Ethylene-tetrafluoroethylene copolymer: purchased from Xin'an Chemical, product number Xinan® PHMS-100.

[0047] Epoxy polymethylphenylsiloxane: purchased from Chemwill, model CW-EP-100.

[0048] Polyether-modified polysiloxane: purchased from Shin-Etsu Chemical, product number KF-92.

[0049] Fumed silica: purchased from Xin'an Chemical, product number Xinan® PHMS-60.

[0050] Low-density polyethylene: purchased from Dongyue Group, product number DY-301H.

[0051] 3-Mercaptopropyltrimethoxysilane: purchased from Bluestar Starfire Co., Ltd., product number BLUESIL FLH 100.

[0052] The present invention will be further illustrated below through specific embodiments: Example 1 The silicone rubber in Example 1 comprises the following raw materials in parts by weight: Phenyl hydrogen-containing polydimethylsiloxane: 70 parts by weight; silicone resin: 9 parts by weight; ethylene-tetrafluoroethylene copolymer: 24 parts by weight; epoxy-based polymethylphenylsiloxane: 16 parts by weight; polyether-modified polysiloxane: 8 parts by weight; fumed silica: 3 parts by weight; mixed powder (including: nano zeolite powder: 2 parts by weight; nano cerium oxide: 1 part by weight); low-density polyethylene: 26 parts by weight; lubricant: 1 part by weight; initiator: 1.2 parts by weight.

[0053] The fumed silica in Example 1 is a fumed silica grafted with a mercaptosilane coupling agent, and the preparation method includes the following steps: 3-Mercaptopropyltrimethoxysilane and fumed silica (D50 approximately 30 nm) in a weight ratio of 1:2 were stirred and reacted at 80 °C for 3 h. The precipitate was collected, washed, and dried to obtain fumed silica grafted with mercaptosilane coupling agent.

[0054] The initiator in Example 1 includes a cationic initiator and a free radical initiator in a weight ratio of 1:1, wherein the cationic initiator is I-250 and the free radical initiator is 1-hydroxy-cyclohexylbenzophenone.

[0055] The silicone resin in Example 1 was prepared by the following method: 3-Aminophenylboronic acid, tetraethyl orthosilicate, and deionized water in a weight ratio of 3:2:5 were added to a three-necked flask. Acetic acid was then added to adjust the pH to 6. The mixture was subjected to a hydrolysis-condensation reaction at 60°C for 4 hours. The reaction system was then separated, and water and solvent were removed by vacuum distillation. Gallic acid was added, and the mixture was allowed to stand for 1 hour to obtain the silicone resin. The weight ratio of 3-aminophenylboronic acid to gallic acid was 3:1.5.

[0056] The method for preparing the silicone rubber in Example 1 includes the following steps: S1. Polyether-modified polysiloxane and phenyl hydrogen-containing polydimethylsiloxane are added to a reaction vessel according to the specified ratio and stirred at 70°C. Then, ethylene-tetrafluoroethylene copolymer, epoxy-based polymethylphenylsiloxane, low-density polyethylene, lubricant, fumed silica and silicone resin are added and mixed evenly. The mixture is stirred at 250 rpm for 10 min and then an initiator is added. The mixture is stirred at 300 rpm for 3 min to obtain a premix. S2. The premix obtained in step S1 is loaded into a mold for casting, and then subjected to ultraviolet irradiation treatment using an ultraviolet curing machine. During the ultraviolet irradiation process, the irradiation wavelength is 160nm and the irradiation intensity is 60mW / cm². 2 Silicone rubber was prepared by irradiation for 120 seconds.

[0057] Example 2 The silicone rubber in Example 2 comprises the following parts by weight of raw materials: Phenyl hydrogen-containing polydimethylsiloxane: 60 parts by weight; silicone resin: 10 parts by weight; ethylene-tetrafluoroethylene copolymer: 20 parts by weight; epoxy-based polymethylphenylsiloxane: 30 parts by weight; polyether-modified polysiloxane: 5 parts by weight; fumed silica: 8 parts by weight; low-density polyethylene: 20 parts by weight; lubricant: 2 parts by weight; initiator: 1.2 parts by weight.

[0058] The fumed silica in Example 2 is fumed silica grafted with a mercaptosilane coupling agent, and the preparation method is the same as in Example 1.

[0059] The initiator in Example 2 is the same as in Example 1.

[0060] The preparation method of the silicone resin in Example 2 is the same as that in Example 1.

[0061] The method for preparing the silicone rubber in Example 2 includes the following steps: S1. Polyether-modified polysiloxane and phenyl hydrogen-containing polydimethylsiloxane are added to a reaction vessel according to the specified ratio and stirred at 60°C. Then, ethylene-tetrafluoroethylene copolymer, epoxy-based polymethylphenylsiloxane, low-density polyethylene, lubricant, fumed silica and silicone resin are added and mixed evenly. The mixture is stirred at 250 rpm for 20 min. Then, an initiator is added and the mixture is stirred at 300 rpm for 2 min to obtain a premix. S2. The premix obtained in step S1 is loaded into a mold for casting, and then subjected to ultraviolet irradiation treatment using an ultraviolet curing machine. During the ultraviolet irradiation process, the irradiation wavelength is 160nm and the irradiation intensity is 80mW / cm². 2 Silicone rubber was obtained by irradiation for 100 seconds.

[0062] Example 3 The silicone rubber in Example 3 comprises the following parts by weight of raw materials: Phenyl hydrogen-containing polydimethylsiloxane: 70 parts by weight; silicone resin: 5 parts by weight; ethylene-tetrafluoroethylene copolymer: 30 parts by weight; epoxy-based polymethylphenylsiloxane: 10 parts by weight; polyether-modified polysiloxane: 15 parts by weight; fumed silica: 3 parts by weight; mixed powder (including: nano zeolite powder: 2 parts by weight; nano cerium oxide: 1 part by weight); low-density polyethylene: 30 parts by weight; lubricant: 0.8 parts by weight; initiator: 1.2 parts by weight.

[0063] The fumed silica in Example 3 is a fumed silica grafted with a mercaptosilane coupling agent, and the preparation method is the same as in Example 1.

[0064] The initiator in Example 3 is the same as in Example 1.

[0065] The preparation method of the silicone resin in Example 3 includes the following steps: 3-Aminophenylboronic acid, tetraethyl orthosilicate and deionized water in a weight ratio of 3:2:5 were added to a three-necked flask, and acetic acid was added to adjust the pH to 6. The hydrolysis-condensation reaction was carried out at 60°C for 4 hours. The reaction system was then separated, and water and solvent were removed by vacuum distillation to obtain silicone resin.

[0066] The preparation method of the silicone rubber in Example 3 includes the following steps: S1. Polyether-modified polysiloxane and phenyl hydrogen-containing polydimethylsiloxane are added to a reaction vessel according to the specified ratio and stirred at 60°C. Then, ethylene-tetrafluoroethylene copolymer, epoxy-based polymethylphenylsiloxane, low-density polyethylene, lubricant, fumed silica and silicone resin are added and mixed evenly. The mixture is stirred at 250 rpm for 20 min. Then, an initiator is added and the mixture is stirred at 300 rpm for 2 min to obtain a premix. S2. The premix obtained in step S1 is loaded into a mold for casting, and then subjected to ultraviolet irradiation treatment using an ultraviolet curing machine. During the ultraviolet irradiation process, the irradiation wavelength is 160nm and the irradiation intensity is 80mW / cm². 2 Silicone rubber was obtained by irradiation for 100 seconds.

[0067] Example 4 The silicone rubber in Example 4 comprises the following parts by weight of raw materials: Phenyl hydrogen-containing polydimethylsiloxane: 50 parts by weight; silicone resin: 15 parts by weight; ethylene-tetrafluoroethylene copolymer: 20 parts by weight; epoxy-based polymethylphenylsiloxane: 30 parts by weight; polyether-modified polysiloxane: 15 parts by weight; fumed silica: 5 parts by weight; low-density polyethylene: 30 parts by weight; lubricant: 0.8 parts by weight; initiator: 1.2 parts by weight.

[0068] The fumed silica in Example 4 is a fumed silica grafted with a mercaptosilane coupling agent, and the preparation method is the same as in Example 1.

[0069] The initiator in Example 4 is the same as in Example 1.

[0070] The preparation method of the silicone resin in Example 4 is the same as that in Example 3.

[0071] The preparation method of the silicone rubber in Example 4 includes the following steps: S1. Polyether-modified polysiloxane and phenyl hydrogen-containing polydimethylsiloxane are added to a reaction vessel according to the specified ratio and stirred at 70°C. Then, ethylene-tetrafluoroethylene copolymer, epoxy-based polymethylphenylsiloxane, low-density polyethylene, lubricant, fumed silica and silicone resin are added and mixed evenly. The mixture is stirred at 250 rpm for 10 min and then an initiator is added. The mixture is stirred at 300 rpm for 5 min to obtain a premix. S2. The premix obtained in step S1 is loaded into a mold for casting, and then subjected to ultraviolet irradiation treatment using an ultraviolet curing machine. During the ultraviolet irradiation process, the irradiation wavelength is 160nm and the irradiation intensity is 80mW / cm². 2 Silicone rubber was obtained by irradiation for 100 seconds.

[0072] Example 5 The silicone rubber in Example 5 comprises the following parts by weight of raw materials: Phenyl hydrogen-containing polydimethylsiloxane: 80 parts by weight; silicone resin: 3 parts by weight; ethylene-tetrafluoroethylene copolymer: 40 parts by weight; epoxy-based polymethylphenylsiloxane: 10 parts by weight; polyether-modified polysiloxane: 15 parts by weight; fumed silica: 5 parts by weight; low-density polyethylene: 20 parts by weight; lubricant: 2 parts by weight; initiator: 1.2 parts by weight.

[0073] The fumed silica in Example 5 is fumed silica grafted with a mercaptosilane coupling agent, and the preparation method is the same as in Example 1.

[0074] The initiator in Example 5 is the same as in Example 1.

[0075] The preparation method of the silicone resin in Example 5 is the same as that in Example 3.

[0076] The method for preparing the silicone rubber in Example 5 includes the following steps: S1. Polyether-modified polysiloxane and phenyl hydrogen-containing polydimethylsiloxane are added to a reaction vessel according to the specified ratio and stirred at 70°C. Then, ethylene-tetrafluoroethylene copolymer, epoxy-based polymethylphenylsiloxane, low-density polyethylene, lubricant, fumed silica and silicone resin are added and mixed evenly. The mixture is stirred at 250 rpm for 10 min and then a photoinitiator is added. The mixture is stirred at 300 rpm for 5 min to obtain a premix. S2. The premix obtained in step S1 is loaded into a mold for casting, and then subjected to ultraviolet irradiation treatment using an ultraviolet curing machine. During the ultraviolet irradiation process, the irradiation wavelength is 160nm and the irradiation intensity is 40mW / cm². 2 Silicone rubber was obtained by irradiation for 300 seconds.

[0077] Comparative Example 1 The silicone rubber in Comparative Example 1 comprises the following raw materials in parts by weight: Phenyl hydrogen-containing polydimethylsiloxane: 50 parts by weight; silicone resin: 20 parts by weight; ethylene-tetrafluoroethylene copolymer: 24 parts by weight; epoxy-based polymethylphenylsiloxane: 10 parts by weight; polyether-modified polysiloxane: 8 parts by weight; fumed silica: 5 parts by weight; low-density polyethylene: 26 parts by weight; lubricant: 1 part by weight; initiator: 1.2 parts by weight.

[0078] The fumed silica in Comparative Example 1 is fumed silica grafted with mercaptosilane coupling agent and prepared by the same method as in Example 1.

[0079] The preparation method of the silicone resin in Comparative Example 1 is the same as that in Example 1.

[0080] The initiator in Comparative Example 1 is the same as in Example 1.

[0081] The preparation method of the silicone rubber in Comparative Example 1 is the same as that in Example 1.

[0082] Comparative Example 2 The silicone rubber in Comparative Example 2 comprises the following raw materials in parts by weight: Phenyl hydrogen-containing polydimethylsiloxane: 50 parts by weight; silicone resin: 3 parts by weight; ethylene-tetrafluoroethylene copolymer: 24 parts by weight; epoxy-based polymethylphenylsiloxane: 10 parts by weight; polyether-modified polysiloxane: 8 parts by weight; fumed silica: 15 parts by weight; low-density polyethylene: 26 parts by weight; lubricant: 1 part by weight; initiator: 1.2 parts by weight.

[0083] The fumed silica in Comparative Example 2 is fumed silica grafted with mercaptosilane coupling agent, and the preparation method is the same as in Example 1.

[0084] The preparation method of the silicone resin in Comparative Example 2 is the same as that in Example 1.

[0085] The initiator in Comparative Example 2 is the same as in Example 1.

[0086] The preparation method of the silicone rubber in Comparative Example 2 is the same as that in Example 1.

[0087] Performance testing: (1) Test the tensile strength of silicone rubber in accordance with the requirements of GB / T 528-2009.

[0088] (2) Antibacterial performance test: The antibacterial rate of silicone rubber against Staphylococcus aureus was determined according to the standard GB / T21866-2008.

[0089] (3) Contact angle test: The contact angle of silicone rubber was measured using an interfacial tension meter.

[0090] The results of the above measurements are shown in Table 1.

[0091] Table 1

[0092] Analysis of the data in Table 1 shows that insufficient addition of silicone resin reduces the antibacterial properties of silicone rubber, while excessive addition affects its tensile strength. Excessive addition of modified fumed silica reduces the photocuring and tensile strength of silicone rubber, while insufficient addition affects its contact angle, thus impacting its hydrophobic effect and consequently the antibacterial efficacy of the antibacterial silicone rubber.

[0093] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A silicone rubber, characterized in that, The silicone rubber comprises the following raw materials in parts by weight: Phenyl hydrogen-containing polydimethylsiloxane: 50 parts to 80 parts; Silicone resin: 3 to 15 parts; Ethylene-tetrafluoroethylene copolymer: 20 parts to 40 parts; Epoxy-based polymethylphenylsiloxane: 10 to 30 parts; Polyether-modified polysiloxane: 5 parts to 15 parts; Fumed silica: 5 to 10 parts; Low-density polyethylene: 20 to 30 parts; Lubricant: 0.8 parts to 2 parts; Initiator: 0.6 parts to 1.6 parts; The raw materials for the silicone resin include 3-aminophenylboronic acid.

2. The silicone rubber as described in claim 1, characterized in that, The fumed silica is a fumed silica grafted with a mercaptosilane coupling agent.

3. The silicone rubber as described in claim 2, characterized in that, In the preparation process of the fumed silica grafted with the mercaptosilane coupling agent, the weight ratio of the mercaptosilane coupling agent to the fumed silica is (10~50):(80~100).

4. The silicone rubber as described in claim 1, characterized in that, The phenyl-containing hydrogen polydimethylsiloxane has a viscosity of 600 cSt to 800 cSt, a phenyl content of 12 wt% to 15 wt%, and a hydrogen content of 0.3 wt% to 0.6 wt%.

5. The silicone rubber as described in claim 1, characterized in that, The viscosity of the polyether-modified polysiloxane is 30 cSt to 70 cSt.

6. The silicone rubber as described in claim 1, characterized in that, The raw materials of the silicone resin include 3-aminophenylboronic acid and tetraethyl orthosilicate in a weight ratio of (50-150):(40-80).

7. The silicone rubber as described in claim 1, characterized in that, The raw materials of the silicone resin include 3-aminophenylboronic acid, tetraethyl orthosilicate and gallic acid in a weight ratio of (50~150):(40~80):(18~35).

8. The silicone rubber as described in claim 1, characterized in that, The silicone rubber comprises the following raw materials in parts by weight: Phenyl hydrogen-containing polydimethylsiloxane: 60-70 parts; Silicone resin: 5 to 10 parts; Ethylene-tetrafluoroethylene copolymer: 20 to 30 parts; Epoxy-based polymethylphenylsiloxane: 10 to 30 parts; Polyether-modified polysiloxane: 5 parts to 15 parts; Fumed silica: 6 to 8 parts; Low-density polyethylene: 20 to 30 parts; Lubricant: 0.8 parts to 2 parts; Initiator: 0.6 parts to 1.6 parts.

9. A method for preparing silicone rubber according to any one of claims 1 to 8, characterized in that, The method for preparing the silicone rubber includes the following steps: S1. Add polyether-modified polysiloxane and phenyl hydrogen-containing polydimethylsiloxane to a reaction vessel according to the ratio, stir and react at 60℃~70℃, then add ethylene-tetrafluoroethylene copolymer, epoxy-based polymethylphenylsiloxane, low-density polyethylene, lubricant, initiator, fumed silica and silicone resin and mix evenly to obtain a premix. S2. The premix obtained in step S1 is loaded into a mold for casting and subjected to ultraviolet irradiation treatment to obtain silicone rubber.

10. The method for preparing silicone rubber according to claim 8, characterized in that, In step S2, during the ultraviolet irradiation process, the irradiation wavelength is 100nm~200nm; the irradiation intensity is 1mW / cm². 2 ~100mW / cm 2 Irradiation time: 30s~300s.

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