A water-responsive organic silicon elastomer material and its preparation method and application

Abstract

The present invention discloses a water-responsive organosilicon elastomer material and its preparation method and application, which is polymerized after mixing an organosilicon main agent, a cross-linking agent, and an inorganic salt aqueous solution; the organosilicon main agent and the cross-linking agent are the A and B components in Sylgard184 of Dow Corning Company, or the A and B components in KER-4690 of UV-curing organosilicon of Shin-Etsu Silicone Company. The prepolymer liquid of the water-responsive PDMS material of the present invention is a mixed emulsion with a certain viscosity, so it can be easily compounded with a non-sensitive substrate by coating or 3D printing to obtain a material or device with responsive characteristics. Finally, due to the good biocompatibility and good mechanical properties of the obtained composite material itself, its application range is relatively wide, and it should have great application value and market potential in today's rapid development of biomaterials and life sciences.

Description

Technical Field

[0001] The invention belongs to the field of polymer materials, and in particular relates to a water-responsive organic silicon elastomer material and a preparation method and application thereof. Background Art

[0002] The main chain of polydimethylsiloxane (PDMS) is an "inorganic structure" composed of alternating Si-O-Si bonds, which is very stable. The side chain is an "organic structure" composed of hydrocarbon groups. This unique combination of inorganic and organic structures gives it good mechanical properties, stable physical and chemical properties, and excellent bioaffinity. It is widely used in the fields of biomaterials and surface materials.

[0003] However, due to the structure of PDMS itself, PDMS finished products generally have the characteristics of low surface energy and high hydrophobicity. Our organisms contain a lot of water, so in order to make biomaterials more compatible, it is necessary to change the compatibility of the PDMS material itself with water. Based on this, researchers have introduced a series of hydrophilic groups such as amino, hydroxyl and carboxyl groups into the chemical structure of polydimethylsiloxane, or made hydrophilic chemical modifications to the surface of the PDMS finished product to improve its compatibility with water and expand its application range. However, these current chemical modification methods are often complicated, and will reduce the stability of the polydimethylsiloxane structure itself and may increase its biological toxicity.

[0004] Therefore, preparing water-compatible and water-responsive silicone elastomers through simple and effective methods is of great significance for their application in the fields of biomaterials and surface materials. Summary of the invention

[0005] Purpose of the invention: The technical problem to be solved by the present invention is to provide a water-compatible and water-responsive organic silicone elastomer material in view of the shortcomings of the prior art, which can change its own performance according to the changes in the external water environment so as to better adapt to the use environment.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A water-responsive organic silicon elastomer material, which is prepared by mixing an organic silicon main agent, a cross-linking agent, and an inorganic salt aqueous solution and polymerizing them;

[0008] The organic silicon main agent and cross-linking agent are components A and B of the heat-curing organic silicon Sylgard184 produced by Dow Corning, or components A and B of the UV-curing organic silicon KER-4690 produced by Shin-Etsu Silicone.

[0009] Specifically, the inorganic salt aqueous solution is any one of LiCl, LiBr, NaCl, CaCl2, or KCl aqueous solution, and its concentration is 2wt% to 50wt%.

[0010] Furthermore, the mass ratio of the organic silicon main agent to the cross-linking agent is 1:1 to 10:1.

[0011] Preferably, the inorganic salt aqueous solution accounts for 1% to 66% of the total mass of the organic silicon main agent, the cross-linking agent and the inorganic salt aqueous solution.

[0012] Furthermore, the present invention also provides a method for preparing the water-responsive organic silicon elastomer material, comprising the following steps:

[0013] (1) mixing the organosilicon main agent and the cross-linking agent, and then stirring with a magnetic force to obtain a PDMS solution;

[0014] (2) fully mixing the inorganic salt aqueous solution with the PDMS solution obtained in step (1) to obtain a mixed emulsion;

[0015] (3) The mixed emulsion obtained in step (2) is coated on a substrate by coating or 3D printing, and then polymerized after vacuum degassing.

[0016] Specifically, in step (3), the substrate is a PDMS film.

[0017] Preferably, in step (3), when the organosilicon main agent and the cross-linking agent are components A and B in Dow Corning's thermosetting organosilicon Sylgard 184, the polymerization temperature is 50°C-120°C.

[0018] Preferably, in step (3), when the organic silicon main agent and the cross-linking agent are components A and B of UV curing organic silicon KER-4690 produced by Shin-Etsu Silicone, the wavelength range of the UV light source is 320nm-390nm.

[0019] Furthermore, in step (3), after vacuum degassing, prepolymerization and shaping can be carried out first, and after the desired shape is obtained, full polymerization is finally carried out.

[0020] Furthermore, the present invention also claims to protect the use of the above water-responsive silicone elastomer material as a biomedical material for preparing a vascular stent.

[0021] Furthermore, the present invention also claims to protect the use of the above-mentioned water-responsive silicone elastomer material as a surface material for preparing a water-sensitive sensor.

[0022] Beneficial effects:

[0023] (1) The present invention first disperses the filled inorganic salt solution in the form of uniform droplets in a mixture of an organic silicon polymer main agent and a crosslinking agent by mechanical stirring to form a uniform emulsion. Then, the emulsion is coated on a non-responsive PDMS substrate or coated on the surface of a non-water-sensitive PDMS substrate in the form of a texture or pattern by a 3D printer, and a water-responsive composite material or device is obtained through a polymerization reaction at a certain temperature or under UV light.

[0024] (2) The preparation process of the water-responsive PDMS polymer material of the present invention does not involve any changes to its chemical structure, and therefore does not change the chemical stability and biocompatibility of the organosilicon structure itself. In addition, the preparation method and process of the water-responsive PDMS material designed in the present invention are simple and environmentally friendly, do not involve any organic solvents, and the raw materials used are all commercial materials, so the preparation cost is relatively low.

[0025] (3) The prepolymer of the water-responsive PDMS material designed by the present invention is a mixed emulsion with a certain viscosity, so it can be easily composited with a non-sensitive substrate by coating or 3D printing to obtain a material or device with responsive characteristics. The obtained composite material itself has good biocompatibility and good mechanical properties, so its application range is relatively wide, and it should have great application value and market potential in today's rapid development of biomaterials and life sciences. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more clear.

[0027] Figure 1 Water-sensitive test of the double-layer thin film material obtained in Example 1 and the corresponding microstructural changes.

[0028] Figure 2 Cytotoxicity experimental data of the double-layer thin film material obtained in Example 1.

[0029] Figure 3 Photo of the spiral double-layer water-sensitive PDMS material obtained in Example 2 deforming when exposed to water.

[0030] Figure 4 Photo of the coil-shaped double-layer water-sensitive PDMS deformable material obtained in Example 3 deforming when exposed to water.

[0031] Figure 5 The dynamic surface sample photo obtained in Example 8 and the laser confocal microscopy picture of the changes in its surface when exposed to water. DETAILED DESCRIPTION

[0032] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples are only used to explain the present invention and are not used to limit the scope of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0033] Example 1

[0034] The raw materials include: organic silicon polymer main agent (60 wt%), organic silicon crosslinking agent (6 wt%), inorganic salt aqueous solution (34 wt%). The organic silicon main agent is organic silicon Sylgard 184 A, and the organic silicon crosslinking agent is Sylgard 184 B. The inorganic salt aqueous solution is 10 wt% NaCl aqueous solution.

[0035] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0036] (1) Preparation of PDMS solution: Sylgard 184 A and Sylgard 184 B were first mixed in a mass ratio of 10:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0037] (2) Doping with inorganic salt solution: gradually add 34 wt % NaCl aqueous solution (10 wt %) into the prepared PDMS solution while stirring, and finally prepare a uniform emulsion mixture by fully stirring.

[0038] (3) The emulsion is coated on a pre-prepared PDMS substrate, and bubbles are removed. The emulsion is polymerized at 80° C. for 24 h to obtain a water-sensitive double-layer deformation PDMS composite material.

[0039] Figure 1 In the figure, (a) is the deformation test of the strip-shaped double-layer PDMS film material obtained in Example 1 after being immersed in 37°C water for different time periods and the deformation recovery of the material after being placed in 80°C air for 180s. Figure 1 In (b), the corresponding optical microscope image of the microstructure of the material shown in (a) is shown. Figure 1 In (a), it can be seen that after the strip PDNS film is immersed in water for 600s, the central angle of the material changes to 341°, indicating that the composite material has a good water-sensitive deformation effect; and when the material is placed in hot air for 180s, the shape almost returns to its original state, indicating that the material has a good reversible deformation effect. Through microscopic observation in (b), it can be clearly seen that its water sensitivity depends on the evolution of its internal microstructure after the material absorbs water.

[0040] Figure 2The cytotoxicity experimental data of the strip double-layer PDMS obtained in Example 1. First, 2.5 mg and 5 mg of double-layer PDMS film material (RSMPDMS) and ordinary PDMS were immersed in 1 mL of cell culture medium respectively and kept at 37°C for 24 hours. Afterwards, the culture medium was used to culture and monitor human stem cells. Figure 2 The data show that the cell viability of the RSMPDMS sample prepared in Example 1 is higher than 96%, and its good biocompatibility is well confirmed.

[0041] Example 2

[0042] The raw materials include: organic silicon polymer main agent (60 wt%), organic silicon crosslinking agent (6 wt%), inorganic salt aqueous solution (34 wt%). The organic silicon main agent is organic silicon Sylgard 184 A, and the organic silicon crosslinking agent is Sylgard 184 B. The inorganic salt aqueous solution is 10 wt% CaCl2 aqueous solution.

[0043] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0044] (1) Preparation of PDMS solution: Sylgard 184 A and Sylgard 184 B were first mixed in a mass ratio of 10:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0045] (2) Doping with inorganic salt solution: 34 wt % CaCl 2 aqueous solution (10 wt %) was gradually added to the prepared PDMS solution while stirring, and finally a uniform emulsion mixture was prepared by sufficient stirring.

[0046] (3) The above emulsion is coated on a pure PDMS substrate that has been prepolymerized at 80°C for 20 minutes, and the bubbles are removed. The polymerization is then continued at 80°C for 20 minutes. The double-layer film is formed into a spiral shape and fixed. The reaction is then continued at 80°C for 24 hours to obtain a spiral PDMS composite material with water-sensitive properties.

[0047] Figure 3 This is a photograph of the spiral double-layer water-sensitive PDMS material obtained in Example 2 deforming when exposed to water. It can be seen that the material obtained by this method has a good shape fixing effect, and the prepared spiral sample has an obvious deformation effect in water, wherein the inner diameter of the spiral tube is significantly widened after being exposed to water, indicating that the material has potential application value in the field of vascular stents.

[0048] Example 3

[0049] The raw materials include: organic silicon polymer main agent (60 wt%), organic silicon crosslinking agent (6 wt%), inorganic salt aqueous solution (34 wt%). The organic silicon main agent is organic silicon Sylgard 184 A, and the organic silicon crosslinking agent is Sylgard 184 B. The inorganic salt aqueous solution is 10 wt% LiCl aqueous solution.

[0050] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0051] (1) Preparation of PDMS solution: Sylgard 184 A and Sylgard 184 B were first mixed in a mass ratio of 10:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0052] (2) Doping with inorganic salt solution: gradually add 34 wt % LiCl aqueous solution (10 wt %) into the prepared PDMS solution while stirring, and finally prepare a uniform emulsion mixture by fully stirring.

[0053] (3) The above emulsion is coated on a pure PDMS substrate that has been prepolymerized at 80°C for 20 minutes, and bubbles are removed. The prepolymerization reaction is then carried out at 80°C for 20 minutes. The double-layer film is formed into a coil shape and fixed. The reaction is continued at 100°C for 12 hours to obtain a coil-shaped PDMS deformation material with water-sensitive properties.

[0054] Figure 4 This is a photo of the coil-shaped double-layer water-sensitive PDMS deformable material obtained in Example 3 deforming when exposed to water. From the data in the figure, it can be seen that the material obtained by this method has a good shape fixing effect. The prepared coil sample deforms significantly after being immersed in water, and the inner diameter size is significantly widened, indicating that the material has potential application value in the field of vascular stents or other medical devices.

[0055] Example 4

[0056] The raw materials include: organic silicon polymer main agent (90wt%), organic silicon crosslinking agent (9wt%), inorganic salt aqueous solution filling material (1wt%). The organic silicon polymer main agent is Sylgard184 A (base), the organic silicon crosslinking agent is Sylgard184 B (linker). The inorganic salt aqueous solution is 50wt% LiBr aqueous solution.

[0057] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0058] (1) Preparation of PDMS solution: Sylgard 184 A and Sylgard 184 B were first mixed in a mass ratio of 10:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0059] (2) Doping with inorganic salt solution: gradually add 1 wt % LiBr aqueous solution (50 wt %) into the prepared PDMS solution while stirring, and finally prepare a uniform emulsion mixture by fully stirring.

[0060] (3) The emulsion is coated on a PDMS substrate and bubbles are removed, followed by reaction at 50° C. for 48 h to obtain a PDMS double-layer film with water-sensitive properties.

[0061] Example 5

[0062] The raw materials include: organic silicon polymer main agent (30wt%), organic silicon crosslinking agent (3wt%), inorganic salt aqueous solution filling material (66wt%). The organic silicon polymer main agent is Sylgard184 A (base), the organic silicon crosslinking agent is Sylgard184 B (linker). The inorganic salt aqueous solution is 2wt% KCl aqueous solution.

[0063] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0064] (1) Preparation of PDMS solution: Sylgard 184 A and Sylgard 184 B were first mixed in a mass ratio of 10:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0065] (2) Doping with inorganic salt solution: gradually add 66 wt % KCl aqueous solution (2 wt %) into the prepared PDMS solution while stirring, and finally prepare a uniform emulsion mixture by fully stirring.

[0066] (3) The emulsion is coated on a PDMS substrate and bubbles are removed, followed by reaction at 120° C. for 3 h to obtain a PDMS double-layer film with water-sensitive properties.

[0067] Example 6

[0068] The raw materials include: organic silicon polymer main agent (40wt%), organic silicon crosslinking agent (40wt%), inorganic salt aqueous solution filling material (20wt%). The organic silicon main agent is organic silica gel KER-4690A, the organic silicon crosslinking agent is KER-4690B. The inorganic salt aqueous solution is 35wt% LiCl aqueous solution.

[0069] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0070] (1) Preparation of PDMS solution: KER-4690A and KER-4690B were first mixed in a mass ratio of 1:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0071] (2) Doping with inorganic salt solution: gradually add 20 wt % LiCl aqueous solution (5 wt %) into the prepared PDMS solution while stirring, and finally prepare a uniform transparent emulsion mixture by fully stirring.

[0072] (3) The above emulsion is coated on a pure PDMS substrate that has been pre-polymerized under UV light for 3 minutes, and the bubbles are removed. The composite film is then polymerized under UV light for 4 minutes (the UV light source is characterized by a wavelength range of 320nm-390nm), and then the polymerization is continued under light for 30 minutes to obtain a water-responsive double-layer PDMS deformation composite material.

[0073] Example 7

[0074] The raw materials include: organic silicon polymer main agent (35wt%), organic silicon crosslinking agent (35wt%), inorganic salt aqueous solution filling material (30wt%). The organic silicon main agent is organic silica gel KER-4690A, and the organic silicon crosslinking agent is KER-4690B. The inorganic salt aqueous solution is 35wt% CaCl2 aqueous solution.

[0075] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0076] (1) Preparation of PDMS solution: KER-4690A and KER-4690B were first mixed in a mass ratio of 1:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0077] (2) Doping with inorganic salt solution: gradually add 30 wt % CaCl 2 aqueous solution (35 wt %) into the prepared PDMS solution while stirring, and finally prepare a uniform transparent emulsion mixture by sufficient stirring.

[0078] (3) The above emulsion is coated on a pure PDMS substrate that has been pre-polymerized under UV light for 3 minutes, and the bubbles are removed. The composite film is then polymerized under UV light for 10 minutes (the UV light source is characterized by a wavelength range of 320nm-390nm), and then the polymerization is continued under light for 60 minutes to obtain a water-responsive double-layer PDMS deformation composite material.

[0079] Example 8

[0080] The raw materials include: organic silicon polymer main agent (60 wt%), organic silicon crosslinking agent (6 wt%), inorganic salt aqueous solution (34 wt%). The organic silicon main agent is organic silicon Sylgard 184 A, and the organic silicon crosslinking agent is Sylgard 184 B. The inorganic salt aqueous solution is 10 wt% NaCl aqueous solution.

[0081] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0082] (1) Preparation of PDMS solution: Sylgard 184 A and Sylgard 184 B were first mixed in a mass ratio of 10:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0083] (2) Doping with inorganic salt solution: gradually add 34 wt % NaCl aqueous solution (10 wt %) into the prepared PDMS solution while stirring, and finally prepare a uniform emulsion mixture by fully stirring.

[0084] (3) After removing bubbles from the emulsion, the emulsion was placed in the needle of a 3D printer, and the designed pattern was printed on a heated PDMS film substrate. The printed surface material was then sealed and prepolymerized at 65°C for 1 hour, and then further cured in an oven at 80°C for 12 hours to obtain a water-responsive dynamic surface structure.

[0085] Figure 5 The following are the actual photos of the dynamic surface sample obtained in Example 8 and the laser confocal micrographs of the surface immersed in 80°C water for different time periods. The data in the figure show that the surface texture obtained has obvious water responsiveness, and the height and width of the surface texture increase accordingly during the immersion in water. This indicates that the material has application value as a surface material for preparing water-sensitive sensors.

[0086] Example 9

[0087] The raw materials include: organic silicon polymer main agent (45wt%), organic silicon crosslinking agent (45wt%), inorganic salt aqueous solution filling material (10wt%). The organic silicon main agent is organic silica gel KER-4690A, the organic silicon crosslinking agent is KER-4690B. The inorganic salt aqueous solution is 35wt% LiCl aqueous solution.

[0088] The preparation method of the water-responsive organic silicon elastomer material comprises the following steps:

[0089] (1) Preparation of PDMS solution: KER-4690A and KER-4690B were first mixed in a mass ratio of 1:1, and then mechanically stirred until uniform to obtain a PDMS solution.

[0090] (2) Doping with inorganic salt solution: gradually add 10 wt % LiCl aqueous solution (35 wt %) into the prepared PDMS solution while stirring, and finally prepare a uniform transparent emulsion mixture by fully stirring.

[0091] (3) After removing bubbles from the emulsion, the emulsion was placed in the needle of a 3D printer, and the designed pattern was printed on the PDMS film substrate. The printed surface material was then polymerized under UV light of 320nm-390nm for 30min to obtain a water-responsive dynamic surface structure.

[0092] The present invention provides a water-responsive organic silicone elastomer material and its preparation method and application ideas and methods. There are many methods and ways to implement the technical solution. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention. All components not specified in this embodiment can be implemented by existing technologies.

Claims

1. A water-responsive silicone elastomer material, characterized in that: It is prepared by mixing and polymerizing an organic silicon main agent, a cross-linking agent, and an inorganic salt aqueous solution; The organic silicon main agent and cross-linking agent are components A and B of Dow Corning's heat-curing organic silicon Sylgard184, or components A and B of Shin-Etsu Silicone's UV-curing organic silicon KER-4690; The inorganic salt aqueous solution is any one of LiCl, LiBr, NaCl, CaCl2, or KCl, and its concentration is 2wt%~50wt%; The mass ratio of the organosilicon main agent to the cross-linking agent is 1:1 to 10:1; The mass proportion of the inorganic salt aqueous solution is 1% to 66% of the total mass of the mixture of the organosilicon main agent, the cross-linking agent and the inorganic salt aqueous solution.

2. The method for preparing the water-responsive silicone elastomer material according to claim 1, characterized in that: The steps include: (1) Mixing the organosilicon main agent and the cross-linking agent, and then stirring magnetically to obtain a PDMS solution; (2) fully mixing the inorganic salt aqueous solution with the PDMS solution obtained in step (1) to obtain a mixed emulsion; (3) The mixed emulsion obtained in step (2) is coated on a substrate by coating or 3D printing, and then polymerized after vacuum degassing.

3. The method for preparing the water-responsive silicone elastomer material according to claim 2, characterized in that: In step (3), the substrate is a PDMS film.

4. The method for preparing the water-responsive silicone elastomer material according to claim 2, characterized in that: In step (3), when the organic silicon main agent and the cross-linking agent are components A and B in Dow Corning's thermosetting organic silicon Sylgard 184, the polymerization temperature is 50°C-120°C; When the organic silicon main agent and the cross-linking agent are the A and B components of the UV curing organic silicon KER-4690 produced by Shin-Etsu Silicone, the wavelength range of the UV light source is 320nm-390nm.

5. The method for preparing the water-responsive silicone elastomer material according to claim 2, characterized in that: In step (3), vacuum degassing is performed followed by prepolymerization and shaping, and finally full polymerization is performed.

6. Use of the water-responsive organosilicon elastomer material according to claim 1 as a biomedical material for preparing a vascular stent.

7. Use of the water-responsive organosilicon elastomer material according to claim 1 as a surface material for preparing a water-sensitive sensor.

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