Antibacterial silicone composition, method for preparing the same, and pillow

Abstract

The application belongs to the technical field of silica gel, and particularly relates to an antibacterial silica gel composition, a preparation method thereof and a pillow. A curing reaction is carried out through a Michael addition mechanism without a catalyst, thereby avoiding the problem that an antibacterial agent containing an N element poisons a platinum gold catalyst of addition type silica gel. An addition type antibacterial silica gel is prepared through a Michael addition reaction of an amino-terminated polyimidazole salt antibacterial agent, poly(dimethylsiloxane)-(methyl aminopropyl siloxane) and acryloyl-terminated poly(dimethylsiloxane) without a catalyst, using acryloyl-terminated poly(dimethylsiloxane) to replace a hydrogen-containing silane as a crosslinking agent, and using the amino-terminated polyimidazole salt antibacterial agent and the poly(dimethylsiloxane)-(methyl aminopropyl siloxane). Compared with condensation type antibacterial silica gel, the addition type antibacterial silica gel has high modulus, high elasticity, high tear strength and high antibacterial effect.

Description

Technical Field

[0001] This application belongs to the field of silicone technology, and specifically relates to an antibacterial silicone composition, its preparation method, and a pillow. Background Technology

[0002] Silicone possesses many unique and superior properties, such as resistance to high and low temperatures, anti-aging properties, hydrophobicity, and good biocompatibility, making it one of the most widely used and valuable polymer materials in the field of medical devices. However, prolonged exposure to the adverse effects of microorganisms can easily lead to bacterial growth on the surface of silicone. Bacterial proliferation can negatively impact the function of medical devices and shorten their lifespan. Furthermore, bacterial growth on silicone can also cause bacterial infections in humans, leading to high morbidity rates. Currently, a simple and effective strategy to reduce bacterial adhesion and growth on the surface of medical devices is to endow silicone with antibacterial properties through functional modification.

[0003] Methods for enhancing the antibacterial properties of silica gel mainly include surface antibacterial modification and intrinsic antibacterial modification. Surface antibacterial modification, such as surface grafting and surface coating, is prone to peeling and leaching, leading to a decrease in antibacterial performance. Furthermore, most surface modification methods require secondary processing, significantly limiting their application and development in the preparation of antibacterial silica gel. Intrinsic antibacterial modification includes physical blending of antibacterial agents and covalent grafting modification. In physical blending, some antibacterial agents not covalently fixed in the cross-linked network may be released from the silica gel into the external environment, causing serious toxic side effects. Therefore, chemical modification to fix the antibacterial agent within the silica gel molecular chain is crucial for the safety and reliability of intrinsic antibacterial silica gel.

[0004] Regarding the chemical modification of antibacterial silicone, one paper (Fuying Dong, Materials Today Communications, doi.org / 10.1016 / j.mtcomm.2020.101695) proposes grafting quaternary ammonium salt groups onto hydroxyl-terminated polydimethylsiloxane via covalent bonds. This allows the antibacterial agent to be integrated into the cross-linked network of the silicone, thus preventing the antibacterial agent from detaching or leaching and ensuring a long-lasting antibacterial effect. However, the prepared antibacterial silicone is a condensation type, with relatively lower mechanical properties, such as tensile strength of 1-5 MPa. Its elasticity is significantly lower than that of addition-type silicone. Furthermore, using TEOS as a cross-linking agent to condense with hydroxyl-terminated polysiloxane containing quaternary ammonium salt groups may result in residual condensation reaction byproducts such as ethanol and water, posing certain health risks when used as materials that come into direct contact with the skin, such as pillows. If hydroxyl-terminated polysiloxanes containing quaternary ammonium salt groups are designed as addition-type silicones, they are incompatible with platinum catalysts (platinum-divinyltetramethyldisiloxane complexes), which can easily lead to catalyst poisoning, thereby inhibiting the hydrosilylation reaction (curing of addition-type silicones). Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention designs an amino-terminated polyimidazolium salt antibacterial agent, poly(dimethylsiloxane)-(methylaminopropylsiloxane), and an acryloyl poly(dimethylsiloxane). The acryloyl poly(dimethylsiloxane) is used to replace the hydrogen-containing silane as a crosslinking agent. An addition-type antibacterial silicone is prepared by a catalyst-free Michael addition reaction with the amino-terminated polyimidazolium salt antibacterial agent and poly(dimethylsiloxane)-(methylaminopropylsiloxane). This avoids the incompatibility between platinum catalysts and nitrogen-containing antibacterial agents that could lead to curing failure. The resulting addition-type antibacterial silicone possesses high modulus, high elasticity, high tear strength, and high antibacterial effect.

[0006] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows: In a first aspect, an antibacterial silicone composition comprises an amino-terminated polyimidazolium salt antibacterial agent, poly(dimethylsiloxane)-(methylaminopropylsiloxane), and an acryloyl-terminated poly(dimethylsiloxane). The general structural formula of the amino-terminated polyimidazolium salt antibacterial agent is as follows: In the formula, n is a positive integer greater than or equal to 1; Preferably, the number average molecular weight of the amino-terminated polyimidazolium salt antibacterial agent is 4000-8000; More preferably, the number average molecular weight of the terminal amino-terminated polyimidazolium salt antibacterial agent is 4000-6000; The poly(dimethylsiloxane)-(methylaminopropylsiloxane) was prepared by ring-opening polymerization of 3-aminopropylheptamethylcyclotetrasiloxane and octamethylcyclotetrasiloxane. The general structural formula of the poly(dimethylsiloxane)-(methylaminopropylsiloxane) is as follows: In the formula, a, b, and c are the same or different, and are positive integers greater than or equal to 1. Preferably, the molar ratio of 3-aminopropylheptamethylcyclotetrasiloxane to octamethylcyclotetrasiloxane is 1:(150-300); Further preferred, the molar ratio of 3-aminopropylheptamethylcyclotetrasiloxane to octamethylcyclotetrasiloxane is 1:(200-250); Preferably, the ring-opening polymerization uses tetramethylammonium silanol as a catalyst; Preferably, the reaction temperature for the ring-opening polymerization is 80-150°C; The terminal acryloyl poly(dimethylsiloxane) is obtained by reacting terminal hydroxypropyl poly(dimethylsiloxane) with ethyl isocyanate acrylate or ethyl isocyanate methacrylate. The general structural formula of terminal acryloyl poly(dimethylsiloxane) is as follows: In the formula, m is a positive integer greater than or equal to 1, and R is selected from hydrogen atoms or methyl groups; Preferably, the number-average molecular weight of the hydroxypropyl-terminated poly(dimethylsiloxane) is 500-5000; Preferably, the number-average molecular weight of the hydroxypropyl-terminated poly(dimethylsiloxane) is 1000-4000; Furthermore, the antibacterial silica gel composition also includes a filler selected from one or more of the following: fumed silica, precipitated silica, quartz powder, diatomaceous earth, kaolin, and calcium carbonate; Preferably, the filler is selected from one or both of fumed silica and precipitated silica; Furthermore, the antibacterial silicone composition also includes a structure control agent, which is selected from one or two of hydroxyl silicone oil and diphenylsilanediol; Preferably, the structure control agent is selected from hydroxyl silicone oil; Preferably, the kinematic viscosity of the hydroxyl silicone oil at 40°C is 10-60 cSt.

[0007] Further, by weight, the antibacterial silicone composition comprises: 4-8 parts by weight of amino-terminated polyimidazolium salt antibacterial agent, 1-10 parts by weight of acryloyl-terminated poly(dimethylsiloxane), 90-110 parts by weight of poly(dimethylsiloxane)-(methylaminopropylsiloxane), 40-80 parts by weight of filler, and 4-8 parts by weight of structure control agent. Preferably, the antibacterial silicone composition comprises, by weight, 5-7 parts of amino-terminated polyimidazolium salt antibacterial agent, 1-10 parts of acryloyl-terminated poly(dimethylsiloxane), 90-110 parts of poly(dimethylsiloxane)-(methylaminopropylsiloxane), 50-70 parts of filler, and 5-7 parts of structure control agent. Preferably, the amount of filler is 50-70 wt% of poly(dimethylsiloxane)-(methylaminopropylsiloxane).

[0008] Secondly, a method for preparing antibacterial silicone, which is obtained by mixing and curing the antibacterial silicone composition described above; Preferably, the antibacterial silicone composition described above is cured at 100-200°C and 5-15 MPa pressure; Preferably, the antibacterial silicone composition described above is first initially cured at 100-150°C and 5-15 MPa pressure, and then deeply cured at 150-200°C and normal pressure.

[0009] The preparation method of antibacterial silica gel specifically includes the following steps: S1. The amino-terminated polyimidazolium salt antibacterial agent is mechanically premixed with the acryloyl poly(dimethylsiloxane); S2. Poly(dimethylsiloxane)-(methylaminopropylsiloxane) is mixed with fillers and structure control agents using a mixer; S3, the premixed product of amino-terminated polyimidazolium salt antibacterial agent and acryloyl poly(dimethylsiloxane) is added to the mixer and mixed to obtain a homogeneous rubber compound. S4. Place the mixed adhesive into the mold for initial curing and molding. The curing conditions are: temperature 100-150℃ and pressure 5-15MPa. S5. Place the pre-cured silicone into a high-temperature oven and cure it at 150-200℃ under normal pressure for 1-4 hours.

[0010] Thirdly, an antibacterial silicone curing material is prepared by the above-described method for preparing antibacterial silicone.

[0011] Fourthly, the above-described antibacterial silicone composition and antibacterial silicone cured products are used in medical and furniture products.

[0012] Fifthly, a pillow is obtained by processing and molding using the antibacterial silicone composition described above.

[0013] The beneficial effects of this invention are as follows: The curing reaction is carried out via a catalyst-free Michael addition mechanism, avoiding the problem of nitrogen-containing antibacterial agents poisoning the platinum catalyst in addition-type silicone. Addition-type antibacterial silicone is prepared by synthesizing an amino-terminated polyimidazolium salt antibacterial agent, poly(dimethylsiloxane)-(methylaminopropylsiloxane), and an acryloyl poly(dimethylsiloxane), using the acryloyl poly(dimethylsiloxane) instead of the hydrogen-containing silane as a crosslinking agent, and reacting with the amino-terminated polyimidazolium salt antibacterial agent and poly(dimethylsiloxane)-(methylaminopropylsiloxane) via a catalyst-free Michael addition reaction. Compared with condensation-type antibacterial silicone, addition-type antibacterial silicone possesses high modulus, high elasticity, high tear strength, and high antibacterial effect. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application and to more completely understand this application and its beneficial effects, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 GPC elution curve of amino-terminated polyimidazolium salt antibacterial agent.

[0016] Figure 2The 1H NMR spectrum of 3-aminopropylheptamethylcyclotetrasiloxane is shown. Detailed Implementation

[0017] The technical solutions in the embodiments 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 some embodiments of the present invention, and not all 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 protection scope of the present invention. It should be noted that the terminology used herein is only for describing specific implementation methods and is not intended to limit the exemplary implementation methods according to the present invention.

[0018] Unless otherwise specified, the experimental conditions used in the examples are generally in accordance with conventional conditions in the art or the conditions recommended by the reagent company. Unless otherwise specified, the materials and reagents used in the examples can be purchased commercially.

[0019] Unless otherwise stated or in case of contradiction, the terms or phrases used herein shall have the following meanings: The terms "and / or," "or / and," and "and / or" as used herein include any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. It should be noted that when at least three items are connected by at least two conjunctions selected from "and / or," "or / and," and "and / or," it should be understood that in this application, the technical solution undoubtedly includes technical solutions connected by "logical AND," and also undoubtedly includes technical solutions connected by "logical OR." For example, "A and / or B" includes three parallel solutions: A, B, and A+B. For example, the technical solution of "A, and / or, B, and / or, C, and / or, D" includes any one of A, B, C, and D (that is, a technical solution that is connected by "logical OR"), as well as any and all combinations of A, B, C, and D, that is, combinations of any two or three of A, B, C, and D, and also combinations of all four of A, B, C, and D (that is, a technical solution that is connected by "logical AND").

[0020] In this application, the terms "multiple", "various", "multiple times", "multi-dimensional", etc., unless otherwise specified, refer to a quantity greater than or equal to 2. For example, "one or more" means one or more than or equal to two.

[0021] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0022] In this application, the technical features described in an open-ended manner include both closed-ended technical solutions composed of the listed features and open-ended technical solutions containing the listed features.

[0023] The preparation of the amino-terminated polyimidazolium salt antibacterial agent was carried out in accordance with the method described in "Preparation and Antibacterial Properties Study of Polyimidazolium Salt Modified Polyurethane Elastomer", Zhu Tianjun et al., Vol. 40, No. 3, 2025. The amino-terminated polyimidazolium salt antibacterial agent was prepared by polycondensation reaction of ethylenediamine, n-butyric acid, glyoxal and formaldehyde in a molar ratio of 1:2:1:1 under the catalysis of 1 mol / L NaOH solution.

[0024] The amino-terminated polyimidazolium salt antibacterial agent, as determined by gel permeation chromatography (GPC), has a number-average molecular weight of 5292, a weight-average molecular weight of 10703, and a polydispersity index of 2.02. Specific elution times in GPC are as follows: Figure 1 As shown.

[0025] Example 1: Synthesis of 3-aminopropylheptamethylcyclotetrasiloxane 383 g of 3-aminopropylmethyldiethoxysilane and 893 g of diethoxydimethylsilane were slowly added to a mixture of 1000 mL toluene, 800 mL of KOH, and 42 g of KOH in an ice-water bath with stirring. The temperature was slowly raised to room temperature during the dropwise addition. After the dropwise addition was completed, the mixture was stirred at room temperature for 2 hours, and then the temperature was raised to 110 °C for 6 hours. After the reaction was completed, the mixture was cooled to room temperature, the aqueous layer was removed, and the organic phase was washed three times with 600 mL of distilled water to remove KOH. The organic phase was dried with MgSO4 for 24 hours, filtered, and concentrated under vacuum to remove the solvent. Then, it was purified by distillation under reduced pressure at a vacuum of 0.13 kPa and 94-98 °C to obtain 3-aminopropylheptamethylcyclotetrasiloxane.

[0026] Structural characterization such as Figure 2 As shown, it specifically includes: 1 ¹H-NMR (400 MHz, CDCl₃): Characteristic peaks are δ=2.69 (t, 2H, -NH₂CH₂-), 1.48 (m, 2H, -CH₂-), 1.42 (s, 2H, -NH₂), 0.53 (t, 2H, -SiCH₂-), and 0.16 (m, 2¹H, 7 -SiCH₃ atoms), which are consistent with the structural characteristics of cyclotetrasiloxane with 1 aminopropyl group, 7 methyl groups, and 4 silicon atoms in the 3-aminopropylheptamethylcyclotetrasiloxane molecule.

[0027] Example 2 Synthesis of poly(dimethylsiloxane)-(methylaminopropylsiloxane) 1.38 g of 3-aminopropylheptamethylcyclotetrasiloxane and 1.6 g of octamethylcyclotetrasiloxane D437 were added to a three-necked flask, with a molar ratio of 1:250. The mixture was heated to 50°C and dehydrated under vacuum for 1 hour. Under nitrogen protection, 4.6 g of tetramethylammonium silanol catalyst was added, and the mixture was heated to 80°C and stirred for 3 hours. The temperature was then raised to 100°C and stirred for another 5 hours. Finally, the temperature was rapidly raised to 150°C and maintained for 30 minutes. Subsequently, the small molecules in the reaction system and the tetramethylammonium silanol catalyst were removed under vacuum, and a colorless viscous liquid, poly(dimethylsiloxane)-(methylaminopropylsiloxane), was obtained.

[0028] Example 3 Synthesis of poly(dimethylsiloxane)-(methylaminopropylsiloxane) 1.38 g of 3-aminopropylheptamethylcyclotetrasiloxane and 4.9 g of octamethylcyclotetrasiloxane D433 were added to a three-necked flask, wherein the molar ratio of the two was 1:225. The remaining operation steps and catalyst dosage were the same as in Example 2.

[0029] Example 4 Synthesis of poly(dimethylsiloxane)-(methylaminopropylsiloxane) 1.38 g of 3-aminopropylheptamethylcyclotetrasiloxane and 96.6 g of octamethylcyclotetrasiloxane D42 were added to a three-necked flask, wherein the molar ratio of the two was 1:200. The remaining operating steps and catalyst dosage were the same as in Example 2.

[0030] Example 5 Synthesis of terminal acryloyl poly(dimethylsiloxane) Using hydroxypropyl-terminated poly(dimethylsiloxane) Silmer® OH Di-10 (Siltech Corporation) as raw material, with a hydroxyl value of 120 mg KOH / g and a number average molecular weight of 1000, 250 g of Silmer® OH Di-10, 84.7 g of isocyanate, 0.8 g of polymerization inhibitor p-hydroxyanisole, and 0.2 g of T12 catalyst (dibutyltin dilaurate) were mixed and reacted at 70 °C for 8 hours. The reaction was detected by infrared spectroscopy, and then excess unreacted isocyanate was removed by vacuum distillation to obtain hydroxypropyl-terminated poly(dimethylsiloxane).

[0031] Example 6 Synthesis of terminal acryloyl poly(dimethylsiloxane) Using hydroxypropyl-terminated poly(dimethylsiloxane) Silmer® OH Di-50 (Siltech Corporation) as raw material, with a hydroxyl value of 28 mg KOH / g and a number-average molecular weight of 4000, 400 g of Silmer® OH Di-50, 35.3 g of isocyanate, 0.5 g of polymerization inhibitor p-hydroxyanisole, and 0.3 g of T12 catalyst (dibutyltin dilaurate) were mixed and reacted at 70 °C for 12 hours. Subsequently, excess unreacted isocyanate was removed by vacuum distillation to obtain acryloyl-terminated poly(dimethylsiloxane).

[0032] Example 7 The antibacterial silicone composition, by weight, comprises: 100 parts by weight of poly(dimethylsiloxane)-(methylaminopropylsiloxane) prepared in Example 2, 1.8 parts by weight of terminal acryloyl poly(dimethylsiloxane) prepared in Example 5, 5.5 parts by weight of terminal amino polyimidazolium salt antibacterial agent, 60 parts by weight of filler silica TS-530, and 6 parts by weight of structure control agent hydroxyl silicone oil (kinematic viscosity of 30 cSt at 40°C).

[0033] Example 8 The antibacterial silicone composition, by weight, comprises: 100 parts by weight of poly(dimethylsiloxane)-(methylaminopropylsiloxane) prepared in Example 2, 6.8 parts by weight of terminal acryloyl poly(dimethylsiloxane) prepared in Example 6, 5.5 parts by weight of terminal amino polyimidazolium salt antibacterial agent, 55 parts by weight of filler silica TS-530, and 5.5 parts by weight of structure control agent hydroxyl silicone oil (kinematic viscosity of 30 cSt at 40°C).

[0034] Example 9 The antibacterial silicone composition, by weight, comprises: 100 parts by weight of poly(dimethylsiloxane)-(methylaminopropylsiloxane) prepared in Example 3, 2.0 parts by weight of terminal acryloyl poly(dimethylsiloxane) prepared in Example 5, 6.0 parts by weight of terminal amino polyimidazolium salt antibacterial agent, 60 parts by weight of filler silica TS-530, and 6 parts by weight of structure control agent hydroxyl silicone oil (kinematic viscosity of 30 cSt at 40°C).

[0035] Example 10 The antibacterial silicone composition, by weight, comprises: 100 parts by weight of poly(dimethylsiloxane)-(methylaminopropylsiloxane) prepared in Example 3, 7.5 parts by weight of terminal acryloyl poly(dimethylsiloxane) prepared in Example 6, 5.8 parts by weight of terminal amino polyimidazolium salt antibacterial agent, 55 parts by weight of filler silica TS-530, and 5.5 parts by weight of structure control agent hydroxyl silicone oil (kinematic viscosity of 30 cSt at 40°C).

[0036] Example 11 The antibacterial silicone composition, by weight, comprises: 100 parts by weight of poly(dimethylsiloxane)-(methylaminopropylsiloxane) prepared in Example 4, 2.2 parts by weight of terminal acryloyl poly(dimethylsiloxane) prepared in Example 5, 6.0 parts by weight of terminal amino polyimidazolium salt antibacterial agent, 60 parts by weight of filler silica TS-530, and 6 parts by weight of structure control agent hydroxyl silicone oil (kinematic viscosity of 30 cSt at 40°C).

[0037] Example 12 The antibacterial silicone composition, by weight, comprises: 100 parts by weight of poly(dimethylsiloxane)-(methylaminopropylsiloxane) prepared in Example 4, 8.3 parts by weight of terminal acryloyl poly(dimethylsiloxane) prepared in Example 6, 6.0 parts by weight of terminal amino polyimidazolium salt antibacterial agent, 55 parts by weight of filler silica TS-530, and 5.5 parts by weight of structure control agent hydroxyl silicone oil (kinematic viscosity of 30 cSt at 40°C).

[0038] The processing and molding methods of the antibacterial silicone compositions in Examples 7-12 above: S1. First, mechanically mix the amino-terminated polyimidazolium salt antibacterial agent and the crosslinking agent terminal acryloyl poly(dimethylsiloxane), and premix the two for 30 minutes using a high-speed disperser; S2. Add poly(dimethylsiloxane)-(methylaminopropylsiloxane) to a two-roll mill, seal it on the surface of the rolls, and ensure uniform spreading. Then add the filler and structure control agent in the formula amount and mix for 30 minutes. S3. Subsequently, the premixed amino-terminated polyimidazolium salt antibacterial agent and crosslinking agent acryloyl poly(dimethylsiloxane) are added to a two-roll mixer and mixed with poly(dimethylsiloxane)-(methylaminopropylsiloxane) and filler for 30 minutes until the system is uniform and free of particles, thereby obtaining antibacterial silicone rubber compound. S4. Place the well-mixed adhesive into a steel mold, set the conditions to 120℃, 10MPa, and 30min, and perform compression molding for initial curing. S5. After molding, remove the silicone and place it in a high-temperature oven. Set the conditions: temperature 195℃, time 2 hours, to complete deep curing and obtain the antibacterial silicone product.

[0039] The antibacterial silicone product was left at room temperature for 24 hours before mechanical property testing was conducted.

[0040] Test section Mechanical property testing: Following the ASTM D 412 method, dumbbell-shaped specimens were prepared by processing silicone. The tensile strength and elongation at break of the specimens were tested, with a tensile rate of 300 mm / min.

[0041] Tear resistance test: Following the ASTM D 624 method, right-angled specimens were prepared by molding silicone, and the tear strength (kN / m) of the specimens was tested. Antimicrobial performance test: The colony counting method was used for testing, targeting two common pathogenic bacteria, Staphylococcus aureus and Escherichia coli, covering Gram-positive and Gram-negative bacteria. The antimicrobial rate of bacterial dilution in contact with silica gel sample for 8 hours and 18 hours was calculated.

[0042] Specific testing method: Different types of bacteria were inoculated onto tryptone soybean agar (TSA) medium and incubated at 37°C for 24 hours. The culture was then diluted to a concentration of 1×10⁻⁶. 5 CFU / mL, take 20mL of diluted bacterial culture medium and place it together with the silica gel sample in a test tube, and calculate the antibacterial rate of the culture medium after contacting the silica gel for a certain period of time according to the formula: a=( N a - N b ) / N a ×100%; Where 'a' represents the antibacterial rate. N a The number of colonies before contact. N b This represents the number of colonies after contact. The test results for Examples 7-12 are recorded in Table 1.

[0043] Table 1 The design concept of antibacterial silicone is to use terminal acryloyl poly(dimethylsiloxane) instead of the hydrogen-containing silane in conventional addition-type silicone as a crosslinking agent. Using the principle of Michael addition reaction, the amino-containing poly(dimethylsiloxane)-(methylaminopropylsiloxane) and the amino-terminated polyimidazolium salt antibacterial agent are crosslinked with the terminal acryloyl poly(dimethylsiloxane) without a catalyst.

[0044] Analysis of the data in Table 1 shows that the antibacterial silicone prepared in Examples 7-12 exhibits more balanced mechanical properties, possessing the characteristics of addition-cure silicone. This allows it to achieve the requirements of high modulus, high elasticity, high tear strength, and high antibacterial effect. The antibacterial agent's terminal amino-imidazolium salt reacts with acryloyl groups to embed into the silicone cross-linking network, achieving antibacterial agent fixation through covalent bonds, thus improving performance stability and preventing leaching and detachment. Furthermore, the antibacterial activity increases with contact time; after 18 hours, the antibacterial silicone shows an antibacterial rate exceeding 97.5% against both types of bacteria, with an antibacterial rate exceeding 99% against Gram-positive Staphylococcus aureus, reaching a highly efficient antibacterial level.

[0045] Finally, it should be noted that the above-described embodiments are merely illustrative of several implementation methods of this application, intended to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the patent application. It should be pointed out that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Furthermore, it should be understood that after reading the above teachings of this application, those skilled in the art can make various alterations or modifications to this application, and the equivalent forms obtained also fall within the scope of protection of this application. It should also be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. An antibacterial silicone composition, characterized in that, Including amino-terminated polyimidazolium salt antibacterial agents, poly(dimethylsiloxane)-(methylaminopropylsiloxane), acryloyl-terminated poly(dimethylsiloxane), fillers, and structure control agents; The structural formula of the amino-terminated polyimidazolium salt antibacterial agent is as follows: In the formula, n is a positive integer greater than or equal to 1; The poly(dimethylsiloxane)-(methylaminopropylsiloxane) was prepared by ring-opening polymerization of 3-aminopropylheptamethylcyclotetrasiloxane and octamethylcyclotetrasiloxane. The general structural formula of the poly(dimethylsiloxane)-(methylaminopropylsiloxane) is as follows: In the formula, a, b, and c are the same or different, and are positive integers greater than or equal to 1. The terminal acryloyl poly(dimethylsiloxane) is obtained by reacting terminal hydroxypropyl poly(dimethylsiloxane) with ethyl isocyanate acrylate or ethyl isocyanate methacrylate. The general structural formula of terminal acryloyl poly(dimethylsiloxane) is as follows: In the formula, m is a positive integer greater than or equal to 1, and R is selected from hydrogen atoms or methyl groups; The filler is selected from one or more of the following: fumed silica, precipitated silica, quartz powder, diatomaceous earth, kaolin and calcium carbonate; The structure control agent is selected from one or two of hydroxyl silicone oil and diphenylsilanediol; The antibacterial silicone composition comprises, by weight: 4-8 parts by weight of amino-terminated polyimidazolium salt antibacterial agent, 1-10 parts by weight of acryloyl-terminated poly(dimethylsiloxane), 90-110 parts by weight of poly(dimethylsiloxane)-(methylaminopropylsiloxane), 40-80 parts by weight of filler, and 4-8 parts by weight of structure control agent.

2. The antibacterial silicone composition according to claim 1, characterized in that, The number-average molecular weight of the terminal amino-terminated polyimidazolium salt antibacterial agent is 4000-8000.

3. The antibacterial silicone composition according to claim 1, characterized in that, The molar ratio of 3-aminopropylheptamethylcyclotetrasiloxane to octamethylcyclotetrasiloxane is 1:(150-300).

4. The antibacterial silicone composition according to claim 1, characterized in that, The ring-opening polymerization uses tetramethylammonium silanol as a catalyst.

5. The antibacterial silicone composition according to claim 1, characterized in that, The reaction temperature for the ring-opening polymerization is 80-150℃.

6. The antibacterial silicone composition according to claim 1, characterized in that, The number-average molecular weight of the terminal hydroxypropyl poly(dimethylsiloxane) is 500-5000.

7. The antibacterial silicone composition according to claim 1, characterized in that, The filler is selected from one or both of fumed silica and precipitated silica.

8. The antibacterial silicone composition according to claim 1, characterized in that, The structure control agent is selected from hydroxyl silicone oil.

9. The antibacterial silicone composition according to claim 8, characterized in that, The kinematic viscosity of the hydroxyl silicone oil at 40°C is 10-60 cSt.

10. A method for preparing antibacterial silica gel, characterized in that, The antibacterial silicone composition according to any one of claims 1-9 is obtained by mixing and curing.

11. The method for preparing antibacterial silica gel according to claim 10, characterized in that, The preparation method specifically includes the following steps: S1. The amino-terminated polyimidazolium salt antibacterial agent is mechanically premixed with the acryloyl poly(dimethylsiloxane); S2. Poly(dimethylsiloxane)-(methylaminopropylsiloxane) is mixed with fillers and structure control agents using a mixer; S3, the premixed product of amino-terminated polyimidazolium salt antibacterial agent and acryloyl poly(dimethylsiloxane) is added to the mixer and mixed to obtain a homogeneous rubber compound. S4. Place the mixed adhesive into the mold for initial curing and molding. The curing conditions are: temperature 100-150℃ and pressure 5-15MPa. S5. Place the pre-cured silicone into a high-temperature oven and cure it at 150-200℃ under normal pressure for 1-4 hours.

12. An antibacterial silicone cured product, characterized in that, It is prepared by the method of any one of claims 10-11 for preparing antibacterial silicone.

13. Use of the antibacterial silicone composition according to any one of claims 1-9 or the antibacterial silicone cured product according to claim 12 in medical products and furniture products.

14. A pillow, characterized in that, It is obtained by processing and molding using the antibacterial silicone composition according to any one of claims 1-9.

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