Porous silica gel elastomer and preparation method thereof

Abstract

The invention belongs to the technical field of high polymer material preparation, and particularly relates to a porous silica gel elastomer and a preparation method thereof. Comprising the following steps: by taking uncured silica gel as an oil phase and taking a glycerol compound or a glyceryl inorganic salt electrolyte system as a water phase, dispersing the water phase into the oil phase in a room-temperature stirring state to form a water-in-oil type high internal phase emulsion; and curing the water-in-oil type high internal phase emulsion to form a silica gel elastomer network containing a water phase, removing the water phase from the silica gel elastomer network containing the water phase, and drying to obtain the porous silica gel elastomer. The high-internal-phase emulsion is stabilized by regulating and controlling the components and properties of the oil phase and the water phase without depending on a traditional surfactant or Pickering solid particles, the porous silica gel elastomer is prepared by taking the high-internal-phase emulsion as a template, the method is simplified, the cost is reduced, and the pore diameter and porosity of the obtained porous material can be regulated and controlled; the prepared porous silica gel elastomer shows certain mechanical strength and good cell compatibility.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer material preparation, and particularly relates to a porous silicone elastomer and a preparation method thereof. Background Art

[0002] Porous silicone elastomers have broad application prospects in biomedicine such as tissue engineering scaffolds or drug release, catalysis, adsorption separation, sensors and other fields due to their good biocompatibility, chemical stability, thermal stability, adjustable pore structure and mechanical properties.

[0003] One common method for preparing porous polymer materials is the High Internal Phase Emulsion (HIPE) template method. HIPEs are emulsions in which the dispersed phase volume fraction exceeds 74%, the theoretical limit for the closest packing of spherical droplets. By polymerizing the continuous phase of a HIPE and then removing the dispersed phase, materials with highly interconnected porous structures can be obtained.

[0004] Traditionally, the stabilization of HIPEs relies on surfactants (forming classic emulsions) or solid particles (forming Pickering emulsions). In classic emulsions, surfactant molecules adsorb at the oil-water interface, reducing interfacial tension and forming a protective film to prevent droplet coalescence. However, the introduction of surfactants can lead to biotoxicity in the final material and can be difficult to remove, impacting material properties. Pickering emulsions utilize the irreversible adsorption of solid particles at the oil-water interface to stabilize the emulsion, which can impart certain functionalities to the material. However, the selection of particles, their dosage control, and compatibility with the system remain issues that require consideration. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a porous silicone elastomer and a preparation method thereof. More specifically, the present invention provides a new method for preparing a porous silicone elastomer using a high internal phase emulsion as a template. The method does not rely on traditional surfactants or Pickering solid particles, but stabilizes the high internal phase emulsion by regulating the oil-water phase components and properties, and uses this as a template to prepare a new method for porous silicone elastomer.

[0006] To achieve the above object, the present invention adopts the following technical solutions: The first object of the present invention is to provide a method for preparing a porous silicone elastomer, comprising the following steps: S1. Using uncured silicone as the oil phase and polyethylene glycol solution, glycerol compound or glycerol-based inorganic salt electrolyte system as the water phase, the water phase is dispersed in the oil phase under stirring at room temperature to form a water-in-oil high internal phase emulsion.

[0007] S2. solidifying the water-in-oil high internal phase emulsion to form a silicone elastomer network containing an aqueous phase, removing the aqueous phase from the silicone elastomer network containing an aqueous phase, and drying to obtain a porous silicone elastomer.

[0008] Furthermore, in the water-in-oil high internal phase emulsion, the volume fraction of the water phase is 60% to 90%.

[0009] Furthermore, the uncured silicone is a two-component addition-type silicone.

[0010] Furthermore, the glycerol compound is glycerol or polyglycerol, and the glycerol-based inorganic salt electrolyte system is a mixture of glycerol and an inorganic salt electrolyte or a mixture of polyglycerol and an inorganic salt electrolyte.

[0011] Furthermore, the inorganic salt is electrolyzed into calcium chloride, and the mass fraction of calcium chloride in the glycerol-based inorganic salt electrolyte system is 5% to 25%.

[0012] Furthermore, the mass concentration of the polyethylene glycol solution is 50% to 55%, and the molecular weight of the polyethylene glycol is 20,000.

[0013] Furthermore, the curing temperature is 30° C. to 60° C., and the curing time is 6 hours to 24 hours.

[0014] Furthermore, the aqueous phase is removed by washing, the washing is performed with boiling water, and the washing time is ≥1h.

[0015] Furthermore, the drying temperature is 80° C. to 120 h, and the drying time is 4 h to 12 h.

[0016] The second object of the present invention is to provide a porous silicone elastomer prepared by the above-mentioned preparation method.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The method for preparing a porous silicone elastomer provided by the present invention utilizes a high internal phase emulsion as a template to prepare the porous silicone elastomer. The method does not rely on traditional surfactants or Pickering solid particles. The high internal phase emulsion is stabilized by regulating the components and properties of the oil-water phase, and the porous silicone elastomer is prepared using the emulsion as a template. This simplifies the emulsion formulation and post-processing process, reduces potential costs and environmental impacts, simplifies the method, and reduces costs. At the same time, the oil phase is selected as uncured silicone, which has good biocompatibility and avoids the cytotoxicity problem that may be caused by surfactant residues, making the prepared porous silicone elastomer more suitable for the biomedical field. By changing the composition of the aqueous phase (such as electrolyte concentration, polyglycerol type) and the internal phase volume fraction, it is expected to regulate the pore size and porosity of the obtained porous material. The prepared porous silicone elastomer exhibits certain mechanical strength and good cell compatibility, and can be used as a cell culture scaffold, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a microscopic image of the water-in-oil high internal phase emulsion prepared in Example 1 of the present invention.

[0019] Figure 2 This is a scanning electron microscope image of the porous silicone elastomer prepared in Examples 1 to 3 of the present invention. Figure 2 (a) is Example 1, (b) is Example 2, and (c) is Example 3.

[0020] Figure 3 This is the infrared spectrum of the porous silicone elastomer prepared in Example 1 of the present invention.

[0021] Figure 4 It is the tensile strength of the porous silicone elastomer prepared in Examples 1 to 5 of the present invention.

[0022] Figure 5 This is a microscopic image of the water-in-oil high internal phase emulsion prepared in Example 7 of the present invention.

[0023] Figure 6 These are the cytotoxicity test results of the porous silica gel materials prepared in Examples 1 to 7 of the present invention. DETAILED DESCRIPTION

[0024] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] It should be noted that the professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Unless otherwise specified, the various raw materials, reagents, instruments and equipment used in the following embodiments of the present invention can be purchased from the market or prepared by existing methods.

[0026] This method stabilizes the emulsion to form a high-internal-phase emulsion, without relying on traditional surfactants or solid particles. Instead, it stabilizes the emulsion by manipulating the properties of the oil-water phase (such as viscosity) or exploiting unique interactions between the interfaces (such as a highly viscous liquid film). Using uncured silicone as the oil phase and a glycerol compound or glycerol-based inorganic salt electrolyte system as the aqueous phase, the exceptional stability of the emulsion is achieved through the thin, highly viscous oil film formed between the aqueous phase droplets. The high-internal-phase emulsion, prepared using this novel stabilization mechanism, serves as a template for preparing porous silicone elastomers with superior properties, providing a new approach for preparing high-purity, highly biocompatible porous materials.

[0027] Based on this, the present invention provides a method for preparing a porous silicone elastomer, comprising the following steps: S1. Using uncured silicone as the oil phase and polyethylene glycol solution, glycerol compound or glycerol-based inorganic salt electrolyte system as the aqueous phase, without relying on traditional surfactants or Pickering solid particles as emulsifiers, the aqueous phase is dispersed in the oil phase under stirring at room temperature to form an oil-in-water type high internal phase emulsion.

[0028] S2. solidifying the water-in-oil high internal phase emulsion to form a silicone elastomer network containing an aqueous phase, removing the aqueous phase from the silicone elastomer network containing an aqueous phase, and drying to obtain a porous silicone elastomer.

[0029] The present invention utilizes a high internal phase emulsion as a template to prepare a porous silicone elastomer, without relying on traditional surfactants or Pickering solid particles. The high internal phase emulsion is stabilized by regulating the components and properties of the oil-water phase, and is used as a template to prepare the porous silicone elastomer, thereby simplifying the emulsion formulation and post-processing process, reducing potential costs and environmental impacts, simplifying the method, and reducing costs. At the same time, the oil phase is selected as uncured silicone, which has good biocompatibility and avoids the cytotoxicity problem that may be caused by surfactant residues, making the prepared porous silicone elastomer more suitable for the biomedical field. By changing the composition of the aqueous phase (such as electrolyte concentration, polyglycerol type) and the volume fraction of the internal phase, it is expected to regulate the pore size and porosity of the obtained porous material. The prepared porous silicone elastomer exhibits certain mechanical strength and good cell compatibility, and can be used as a cell culture scaffold, etc.

[0030] In some embodiments, the volume fraction of the water phase in the water-in-oil high internal phase emulsion is 60% to 90%. Preferably, the volume fraction of the water phase is 65% to 85% to ensure the formation of a high internal phase emulsion, thereby obtaining a material with high porosity.

[0031] In some embodiments, the uncured silicone is a two-component addition-type silicone. Preferably, when the mass ratio of the first component to the second component in the two-component addition-type silicone is 10:1 or 1:1, when the mass ratio of the first component to the second component in the two-component addition-type silicone is 10:1, the two-component addition-type silicone is Kangdaoning SYLGARD 184 silicone, and when the mass ratio of the first component to the second component in the two-component addition-type silicone is 1:1, the two-component addition-type silicone is HY-E series addition-type silicone.

[0032] In some embodiments, the glycerol compound is glycerol or polyglycerol, and the glycerol-based inorganic salt electrolyte system is a mixture of glycerol and an inorganic salt electrolyte or a mixture of polyglycerol and an inorganic salt electrolyte. In a preferred embodiment, the polyglycerol is decaglycerol, which has a higher viscosity and multiple hydroxyl groups, and also helps stabilize the emulsion.

[0033] In some embodiments, the inorganic salt electrolyte is calcium chloride, and the mass fraction of calcium chloride in the glycerol-based inorganic salt electrolyte system is 5% to 25%. Preferably, the mass fraction of calcium chloride in the glycerol-based inorganic salt electrolyte system is 15% to 20%. The addition of calcium chloride helps improve the stability of the emulsion by affecting the interfacial charge or changing the viscosity of the aqueous phase.

[0034] In some embodiments, the mass concentration of the polyethylene glycol solution is 50% to 55%, and the molecular weight of the polyethylene glycol is 20,000.

[0035] In some embodiments, the curing temperature is 30° C. to 60° C., and the curing time is 6 hours to 24 hours. Preferably, the curing temperature is 40° C., and the curing time is 12 hours. A lower curing temperature helps maintain the stability of the emulsion during the curing process.

[0036] In some embodiments, the aqueous phase is removed by washing with boiling water for a time of ≥ 1 h. The aqueous phase and possible residual electrolytes can be effectively removed by washing with boiling water.

[0037] In some embodiments, the drying temperature is 80° C. to 120 h, and the drying time is 4 h to 12 h.

[0038] The following is further described through specific examples.

[0039] Example 1 A method for preparing a porous silicone elastomer comprises the following steps: S1. Prepare the oil phase: Weigh SYLGARD 184 silica gel in a 10:1 mass ratio of the first component to the second component, mix thoroughly, and set aside. Prepare the aqueous phase: Weigh 80g of glycerin and 20g of anhydrous calcium chloride, mix and stir until the calcium chloride is completely dissolved to obtain a 20% calcium chloride-glycerin solution, set aside.

[0040] S2. Weigh 2.5 mL of the oil phase and 7.5 mL of the aqueous phase. Slowly add the aqueous phase dropwise to the oil phase at room temperature while stirring at 400 rpm. Continue stirring until a stable, viscous, white, water-in-oil (W / O) high internal phase emulsion is formed. The volume fraction of the aqueous phase in the W / O high internal phase emulsion is 75%.

[0041] S3. Transfer the high internal phase emulsion to a mold and cure it in a 40°C oven for 12 hours to obtain a silicone elastomer network. Remove the cured silicone elastomer network from the mold, cut it into appropriately sized pieces, and wash it in boiling water, changing the water several times for a total washing time of at least 1 hour to fully remove the glycerin and calcium chloride in the aqueous phase. Dry the washed sample in a 100°C oven for 8 hours to obtain a porous silicone elastomer.

[0042] Example 2 A method for preparing a porous silicone elastomer comprises the following steps: S1. Prepare the oil phase: Weigh SYLGARD 184 silica gel in a 10:1 mass ratio of the first component to the second component, mix thoroughly, and set aside. Prepare the aqueous phase: Weigh 80g of glycerin and 20g of anhydrous calcium chloride, mix and stir until the calcium chloride is completely dissolved to obtain a 20% calcium chloride-glycerin solution, set aside.

[0043] S2. Weigh 2.0 mL of the oil phase and 8.0 mL of the aqueous phase. Slowly add the aqueous phase dropwise to the oil phase at room temperature while stirring at 400 rpm. Continue stirring until a stable, viscous, white, water-in-oil (W / O) high internal phase emulsion is formed. The volume fraction of the aqueous phase in the W / O high internal phase emulsion is 80%.

[0044] S3. Transfer the high internal phase emulsion to a mold and cure it in a 40°C oven for 12 hours to obtain a silicone elastomer network. Remove the cured silicone elastomer network from the mold, cut it into appropriately sized pieces, and wash it in boiling water, changing the water several times for a total washing time of at least 1 hour to fully remove the glycerin and calcium chloride in the aqueous phase. Dry the washed sample in a 100°C oven for 8 hours to obtain a porous silicone elastomer.

[0045] Example 3 A method for preparing a porous silicone elastomer comprises the following steps: S1. Prepare the oil phase: Weigh SYLGARD 184 silica gel in a 10:1 mass ratio of the first component to the second component, mix thoroughly, and set aside. Prepare the aqueous phase: Weigh 80g of glycerin and 20g of anhydrous calcium chloride, mix and stir until the calcium chloride is completely dissolved to obtain a 20% calcium chloride-glycerin solution, set aside.

[0046] S2. Weigh 3.0 mL of the oil phase and 7.0 mL of the aqueous phase. Slowly add the aqueous phase dropwise to the oil phase at room temperature, stirring at 400 rpm, and continue stirring until a stable, viscous, white, water-in-oil (W / O) high internal phase emulsion is formed. The volume fraction of the aqueous phase in the W / O high internal phase emulsion is 70%.

[0047] S3. Transfer the high internal phase emulsion to a mold and cure it in a 40°C oven for 12 hours to obtain a silicone elastomer network. Remove the cured silicone elastomer network from the mold, cut it into appropriately sized pieces, and wash it in boiling water, changing the water several times for a total washing time of at least 1 hour to fully remove the glycerin and calcium chloride in the aqueous phase. Dry the washed sample in a 100°C oven for 8 hours to obtain a porous silicone elastomer.

[0048] Example 4 A method for preparing a porous silicone elastomer comprises the following steps: S1. Prepare the oil phase: Weigh SYLGARD 184 silica gel in a 10:1 mass ratio of the first component to the second component, mix thoroughly, and set aside. Prepare the aqueous phase: Weigh 80g of glycerin and 20g of anhydrous calcium chloride, mix and stir until the calcium chloride is completely dissolved to obtain a 20% calcium chloride-glycerin solution, set aside.

[0049] S2. Weigh 3.5 mL of the oil phase and 6.5 mL of the aqueous phase. Slowly add the aqueous phase dropwise to the oil phase at room temperature, stirring at 400 rpm, and continue stirring until a stable, viscous, white, water-in-oil (W / O) high internal phase emulsion is formed. The volume fraction of the aqueous phase in the W / O high internal phase emulsion is 65%.

[0050] S3. Transfer the high internal phase emulsion to a mold and cure it in a 40°C oven for 12 hours to obtain a silicone elastomer network. Remove the cured silicone elastomer network from the mold, cut it into appropriately sized pieces, and wash it in boiling water, changing the water several times for a total washing time of at least 1 hour to fully remove the glycerin and calcium chloride in the aqueous phase. Dry the washed sample in a 100°C oven for 8 hours to obtain a porous silicone elastomer.

[0051] Example 5 A method for preparing a porous silicone elastomer comprises the following steps: S1. Prepare the oil phase: Weigh SYLGARD 184 silica gel in a 10:1 mass ratio of the first component to the second component, mix thoroughly, and set aside. Prepare the aqueous phase: Weigh 80g of glycerin and 20g of anhydrous calcium chloride, mix and stir until the calcium chloride is completely dissolved to obtain a 20% calcium chloride-glycerin solution, set aside.

[0052] S2. Weigh 4.0 mL of the oil phase and 6.0 mL of the aqueous phase. Slowly add the aqueous phase dropwise to the oil phase at room temperature, stirring at 400 rpm, and continue stirring until a stable, viscous, white, water-in-oil (W / O) high internal phase emulsion is formed. The volume fraction of the aqueous phase in the W / O high internal phase emulsion is 60%.

[0053] S3. Transfer the high internal phase emulsion to a mold and cure it in a 40°C oven for 12 hours to obtain a silicone elastomer network. Remove the cured silicone elastomer network from the mold, cut it into appropriately sized pieces, and wash it in boiling water, changing the water several times for a total washing time of at least 1 hour to fully remove the glycerin and calcium chloride in the aqueous phase. Dry the washed sample in a 100°C oven for 8 hours to obtain a porous silicone elastomer.

[0054] Example 6 A method for preparing a porous silicone elastomer comprises the following steps: S1. Prepare the oil phase: Weigh SYLGARD 184 silica gel in a mass ratio of 10:1 between the first and second components, mix thoroughly, and set aside. Prepare the aqueous phase: Weigh 80g of decaglycerol and 20g of anhydrous calcium chloride, mix and stir until the calcium chloride is completely dissolved to obtain a 20% by mass calcium chloride-decaglycerol solution, set aside.

[0055] S2. Weigh 4.0 mL of the oil phase and 6.0 mL of the aqueous phase. Slowly add the aqueous phase dropwise to the oil phase at room temperature, stirring at 400 rpm, and continue stirring until a stable, viscous, white, water-in-oil (W / O) high internal phase emulsion is formed. The volume fraction of the aqueous phase in the W / O high internal phase emulsion is 60%.

[0056] S3. Transfer the high internal phase emulsion to a mold and cure it in a 40°C oven for 12 hours to obtain a silicone elastomer network. Remove the cured silicone elastomer network from the mold, cut it into appropriately sized pieces, and wash it in boiling water, changing the water several times for a total washing time of at least 1 hour to fully remove the glycerin and calcium chloride in the aqueous phase. Dry the washed sample in a 100°C oven for 8 hours to obtain a porous silicone elastomer.

[0057] Example 7 A method for preparing a porous silicone elastomer comprises the following steps: S1. Prepare the oil phase: Weigh SYLGARD 184 silica gel in a mass ratio of 10:1 between the first component and the second component, mix thoroughly, and set aside. Prepare the aqueous phase: Weigh PEG-20000 and anhydrous calcium chloride, mix glycerol and the calcium chloride solution, and stir until the calcium chloride is completely dissolved to obtain a PEG-20000-calcium chloride solution. The PEG-20000-calcium chloride solution has a mass concentration of 55% PEG-20000, 5% calcium chloride, and the remainder is water.

[0058] S2. Weigh 3 mL of the oil phase and 7 mL of the aqueous phase. Slowly add the aqueous phase dropwise to the oil phase at room temperature, stirring at 400 rpm. Continue stirring until a stable, viscous, white, water-in-oil (W / O) high internal phase emulsion is formed. The volume fraction of the aqueous phase in the W / O high internal phase emulsion is 70%.

[0059] S3. Transfer the high internal phase emulsion to a mold and cure it in a 40°C oven for 12 hours to obtain a silicone elastomer network. Remove the cured silicone elastomer network from the mold, cut it into appropriately sized pieces, and wash it in boiling water, changing the water several times for a total washing time of at least 1 hour to fully remove the glycerin and calcium chloride in the aqueous phase. Dry the washed sample in a 100°C oven for 8 hours to obtain a porous silicone elastomer.

[0060] The porous silicone elastomers prepared in Examples 1 to 5 were subjected to structural and performance tests, and the structures are as follows: Figure 1 This is a microscopic image of the water-in-oil high internal phase emulsion prepared in Example 1 of the present invention. Figure 1 As shown, a large number of densely distributed droplets were observed in the prepared emulsion under an optical microscope, which is consistent with the characteristics of a high internal phase emulsion.

[0061] Figure 2 This is a scanning electron microscope image of the porous silicone elastomer prepared in Examples 1 to 3 of the present invention. Figure 2 (a) is Example 1, (b) is Example 2, and (c) is Example 3. Figure 2 As shown, a pore structure is visible, and a through-hole structure is observed in some areas.

[0062] Figure 3 This is the infrared spectrum of the porous silica gel elastomer prepared in Example 1 of the present invention. Figure 3 As shown, it was observed at 3357 cm -1 、2961cm -1 、1636cm -1 、1257cm -1 、1012cm -1 , 787cm -1 and 450cm -1 The peaks of these wave numbers. Among them, 450cm -1 , 787cm -1 、1009cm -1 and 1257cm -1 The peak is the reflection of the Si-O-Si cross-linked structure of silica gel; 3357cm -1 and 2961cm -1 The peak is from residual glycerol; 1636 cm -1 We speculate that the peak is caused by the cross-linking of calcium ions with glycerol hydroxyl groups or silicon-oxygen networks, which shifts the frequency of the OH bond bending vibration. We can observe the peak at 1410 cm -1 The OH bending vibration peaks on the left and right are very weak, which confirms the mechanism of calcium ion participation.

[0063] Figure 4 is the tensile strength of the porous silicone elastomer prepared in Examples 1 to 5 of the present invention. Figure 4 As shown in the figure, when glycerol-calcium chloride is used as the aqueous phase and the volume fraction of the internal phase is 65%, the tensile strength of the material is higher.

[0064] Figure 5 This is a microscopic image of the water-in-oil high internal phase emulsion prepared in Example 7 of the present invention. Figure 1As shown, a large number of densely distributed droplets were observed in the prepared emulsion under an optical microscope, which is consistent with the characteristics of a high internal phase emulsion.

[0065] The cytotoxicity test of the porous silica gel materials prepared in Examples 1 to 7 was conducted, specifically comprising the following steps: The porous silica gel materials prepared in Examples 1 to 7 were sterilized by treating them under a 356 nm ultraviolet lamp for 2 hours, and then the sterile silica gel materials were cut into pieces and cut into 3 cm 2 Add the cell culture medium at a ratio of 100 μg / mL surface area to extraction medium. Extract at -37°C for 24 hours, then filter through a 0.22 μm filter membrane, collect the extract (stock solution), and dilute to 50% and 25% concentrations for later use.

[0066] L929 fibroblasts were cultured and the density was adjusted to 5 × 10 4 cells / mL to obtain a cell suspension. Add 100 μL of cell suspension to each well of a 96-well plate and fill the edge wells with PBS. Incubate at 37°C, 5% CO2 for 24 hours to allow adherence.

[0067] 100 μL of extracts of different concentrations (stock solution, 50%, 25%) were added to the cell suspension as the experimental group, and the culture medium was used as the blank group, the culture medium + cells as the negative control group, and the culture medium containing 10% DMSO as the positive control group. Each group was set up with 3-6 replicate wells.

[0068] After 48 hours of culture, add 10 μL of CCK8 reagent to each well. Incubate at -37°C in the dark for 2 hours. Measure absorbance (OD) at 450 nm using a microplate reader. Cell viability = [(OD experimental group - OD blank group) / (OD negative control group - OD blank group)] × 100%. A viability > 70% is considered non-cytotoxic.

[0069] Figure 6 These are the cytotoxicity test results of the porous silica gel materials prepared in Examples 1 to 7 of the present invention. Figure 6 In the horizontal coordinate, No. 1 is Example 2, No. 2 is Example 1, No. 3 is Example 3, No. 4 is Example 4, No. 5 is Example 5, No. 6 is Example 6, and No. 7 is Example 7. Figure 6 As shown in the results, the porous silica materials showed no significant cytotoxicity, indicating that they have good biocompatibility.

[0070] In summary, this study successfully prepared a high-internal-phase water-in-oil emulsion that is independent of traditional emulsifiers by selecting an oil phase (uncured silica gel) and an aqueous phase (such as glycerol, polyglycerol, and glycerol containing electrolytes). This emulsion then served as a template for a porous silicone elastomer. The study found that the composition of the aqueous phase (such as the addition of electrolytes and the use of polyglycerol) and the relative ratio of the oil and water phases significantly influenced the emulsion stability and the pore structure and properties of the resulting material. For example, the addition of calcium chloride may stabilize the emulsion by affecting interfacial charge or forming a coordination structure, while decapolyglycerol may rely on its high viscosity and polyhydroxy structure to form a stable interfacial film. These findings provide theoretical basis and technical support for the design and preparation of novel functionalized porous silicone materials.

[0071] It should be noted that when numerical ranges are mentioned in the present invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints may be selected. Since the steps and methods used are the same as those in the embodiments, in order to avoid redundancy, the present invention describes preferred embodiments. Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they understand the basic inventive concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0072] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for preparing a porous silicone elastomer, characterized in that: The following steps are involved: Using uncured silica gel as the oil phase and polyethylene glycol solution, glycerol compound or glycerol-based inorganic salt electrolyte system as the water phase, the water phase is dispersed in the oil phase under stirring at room temperature to form a water-in-oil high internal phase emulsion; The water-in-oil high internal phase emulsion is solidified to form a silicone elastomer network containing a water phase, the water phase is removed from the silicone elastomer network containing a water phase, and a porous silicone elastomer is obtained after drying.

2. The method for preparing a porous silicone elastomer according to claim 1, wherein: In oil-in-water high internal phase emulsions, the volume fraction of the water phase is 60% to 90%.

3. The method for preparing a porous silicone elastomer according to claim 1, wherein: Uncured silicone is a two-component addition type silicone.

4. The method for preparing a porous silicone elastomer according to claim 1, wherein: The glycerol compound is glycerol or polyglycerol, and the glycerol-based inorganic salt electrolyte system is a mixture of glycerol and an inorganic salt electrolyte or a mixture of polyglycerol and an inorganic salt electrolyte.

5. The method for preparing a porous silicone elastomer according to claim 4, characterized in that: The inorganic salt is electrolyzed into calcium chloride, and the mass fraction of calcium chloride in the glycerol-based inorganic salt electrolyte system is 5% to 25%.

6. The method for preparing a porous silicone elastomer according to claim 1, wherein: The mass concentration of the polyethylene glycol solution is 50% to 55%, and the molecular weight of the polyethylene glycol is 20,000.

7. The method for preparing a porous silicone elastomer according to claim 1, wherein: The curing temperature is 30°C to 60°C, and the curing time is 6h to 24h.

8. The method for preparing a porous silicone elastomer according to claim 1, wherein: The aqueous phase is removed by washing with boiling water for a time of ≥1h.

9. The method for preparing a porous silicone elastomer according to claim 1, wherein: The drying temperature is 80℃~120h, and the drying time is 4h~12h.

10. A porous silicone elastomer, characterized in that: The preparation method is described in any one of claims 1 to 9.

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