CN115043969B

CN115043969B - Gel with surface patterning, preparation method and application

Info

Publication number: CN115043969B
Application number: CN202110252368.7A
Authority: CN
Inventors: 王树涛; 万茜子; 贾岚欣; 刘熹
Original assignee: Technical Institute of Physics and Chemistry of CAS
Current assignee: Technical Institute of Physics and Chemistry of CAS
Priority date: 2021-03-08
Filing date: 2021-03-08
Publication date: 2024-03-29
Anticipated expiration: 2041-03-08
Also published as: CN115043969A

Abstract

The invention relates to a method for preparing gel with surface patterning, which comprises the following steps: (1) Providing a patterned substrate having hydrophilic and hydrophobic regions on a surface thereof; (2) Applying an emulsion comprising a hydrogel prepolymerization solution and an oil gel prepolymerization solution to the surface of the patterned substrate, wherein a hydrogel monomer and an oil gel monomer in the prepolymerization solution self-assemble on the surface of the substrate; (3) After the emulsion polymerization was completed and peeled off from the substrate, a gel with patterning was obtained. The invention realizes the patterning of the gel surface by a simple infiltration transfer method, the preparation process is simple and easy to implement, no complex equipment is needed, the preparation of the gel pattern from 2D to 3D and from microcosmic to macroscopic can be realized at the same time, and the prepared pattern has high definition and precision.

Description

Gel with surface patterning, preparation method and application

Technical Field

The invention belongs to the field of gel, and particularly relates to gel with surface patterning, a preparation method and application, a pattern transfer seal comprising the gel and a using method thereof, and further relates to surface patterning gel prepared by utilizing hydrophilic/hydrophobic interaction of a solid/liquid interface, a preparation method and application, a pattern transfer seal comprising the gel and a using method thereof.

Background

The patterned gel can be used for detecting DNA and fluorescent molecules, intelligently driving, screening biomolecules, inducing cell differentiation and the like, and has wide application prospect in actual life, so that the preparation method of the patterned gel is widely focused. In the prior art, various methods can be used for patterning gel, for example, a photodegradable polyethylene glycol-based hydrogel is patterned by using a photolithography method, the physical and chemical properties of the gel can be regulated in time and space by ultraviolet light, and nano-scale patterning is realized in bulk phase, but the method has high requirements on the type of gel, and surface patterning cannot be realized. Patterning of the gel can be achieved by 3D/4D printing methods, but complicated 3D/4D printing equipment is required and the prepared pattern is a bulk pattern. The soft etching technology adopts a template shaping method, gel pre-polymerization liquid is poured on the surface with a specific structure, after photopolymerization, the solidified gel is peeled off from a substrate, and the structure with a specific pattern can be obtained through shaping, but the method can only obtain a 3D pattern with a concave-convex structure through shaping, a 2D pattern cannot be obtained, and the pattern precision is limited. The computer-aided ion ink-jet printing technology can directly print batch and very complex patterns on the surface of a large-size hydrogel sample, but has limitation on the type of gel, and has low precision only on the submicron level. The electron beam etching technology can be used for constructing a fine amine group-containing oligo (ethylene glycol) methacrylate thermal response polymer pattern on the silicon surface, but the method also has the problems of expensive equipment, long time consumption and high requirement on gel types.

Thus, the prior art for preparing patterned gels has generally suffered from the following problems: the gel type is greatly limited, the equipment is expensive, and the preparation is complex; often, only bulk patterning of the gel is achieved, and surface patterning of the gel is difficult to achieve; the partial method has lower precision, and can not realize 2D and 3D patterns and the like at the same time. Accordingly, there is a need in the art to develop a method of preparing a surface patterned gel that can solve the above-described problems.

Disclosure of Invention

In view of the above problems in the prior art, the present invention provides a method for preparing a gel having surface patterning, the method comprising the steps of:

(1) Providing a patterned substrate having hydrophilic and hydrophobic regions on a surface thereof;

(2) Applying emulsion containing hydrogel prepolymerization liquid and oil gel prepolymerization liquid to the surface of the patterned substrate, wherein hydrogel monomers and oil gel monomers in the prepolymerization liquid are self-assembled at a solid-liquid interface;

(3) After the emulsion polymerization was completed and peeled off from the substrate, a gel with patterning was obtained.

After the emulsion is applied to a patterned substrate with hydrophilic and hydrophobic regions on the surface, the emulsion droplets will move directionally due to the induction effect of the hydrophilic/hydrophobic interactions of the solid/liquid interface, the hydrophilic monomers will move to the hydrophilic regions of the substrate due to the hydrophilic interactions, and the hydrophobic monomers will move to the hydrophobic regions of the substrate due to the hydrophobic interactions, i.e. the portion of the emulsion contacting the hydrophilic regions will become the surface region of the hydrophilic hydrogel after gelation, and the portion contacting the hydrophobic regions will become the surface region of the hydrophobic oleogel after gelation. Therefore, the pattern formed on the surface of the substrate due to the wettability difference can be perfectly transferred to the surface of the gel, and the gel with the patterned surface can be obtained.

According to the invention, by selecting emulsion containing hydrogel prepolymer liquid and oil gel prepolymer liquid as a precursor of patterning gel, and utilizing the difference of substrate surface wettability, the directional migration of hydrophilic monomers and hydrophobic monomers in the emulsion is realized through the induction effect of hydrophilic/hydrophobic interaction, and the surface patterning gel is obtained through polymerization molding. The size and dimension of the surface patterning gel pattern are determined by a substrate, a two-dimensional substrate can prepare a two-dimensional gel, and a three-dimensional substrate can prepare a three-dimensional gel; gel pattern sizes can range from microscopic (a few microns to hundreds of microns) to macroscopic (a few hundreds of microns to tens of centimeters). Therefore, by a simple preparation method, the preparation of gel patterns from 2D to 3D and from macroscopic to microscopic can be realized at the same time, and the prepared patterns have high definition and precision.

Preferably, the emulsion comprises an oil-in-water emulsion or a water-in-oil emulsion; mixing the hydrogel prepolymerization liquid and the oil gel prepolymerization liquid, and emulsifying to obtain emulsion; the hydrogel prepolymerization solution comprises hydrogel monomers, a hydrogel monomer initiator and a hydrogel cross-linking agent, wherein the hydrogel monomers, the hydrogel monomer initiator and the hydrogel cross-linking agent are dispersed in water; the oil gel pre-polymerization liquid comprises an oil gel monomer, an oil gel monomer initiator and an oil gel cross-linking agent.

The emulsion includes an oil-in-water emulsion or a water-in-oil emulsion, and a water-in-oil-in-water emulsion or an oil-in-water-in-oil emulsion may also be used, as well as other emulsions comprising hydrophilic monomers and hydrophobic monomers, as long as a two-phase or multi-phase emulsion comprising an aqueous phase and an oil phase can be formed. The emulsion is prepared from hydrogel prepolymer liquid and oil gel prepolymer liquid through ultrasonic post-emulsification. The hydrogel monomer dispersed in water is subjected to cross-linking polymerization under the action of an initiator and a cross-linking agent to form hydrophilic hydrogel; the oil gel monomer is subjected to cross-linking polymerization under the action of an initiator and a cross-linking agent to form hydrophobic oil gel. The hydrogel and the oleogel are tightly bonded by interfacial polymerization.

Preferably, the hydrogel monomer hasAnd a structure, wherein R is a hydrophilic group, and the hydrophilic group comprises any one or a combination of at least two of an amide group, a carboxyl group, a hydroxyl group and an amino group.

Preferably, the hydrogel monomer comprises any one or a combination of at least two of acrylamide, acrylic acid and hydroxyethyl acrylate.

The hydrogel monomer has hydrophilic groups, and proper hydrophilic groups are selected, so that the hydrophilic monomer can generate hydrophilic interaction with modified molecules of a hydrophilic region on the surface of the substrate, and effective migration to the hydrophilic region of the substrate is realized, and the stronger the hydrophilic interaction is, the better the hydrophilic interaction is, so that the clear and continuous boundary of the pattern and the integrity of the pattern are ensured.

Preferably, the hydrogel monomer content in the hydrogel prepolymer solution is 1mol/L to 6mol/L, for example, 1.0mol/L, 1.5mol/L, 2.0mol/L, 2.5mol/L, 3.0mol/L, 3.5mol/L, 4.0mol/L, 4.5mol/L, 5.0mol/L, 5.5mol/L, 6.0mol/L, etc., preferably 2.5mol/L.

The hydrogel monomer content in the hydrogel prepolymer liquid is lower than 1mol/L, so that the mechanical strength of the hydrogel is poor, and the amount of monomers capable of moving towards an interface is small, so that the integrity of the pattern is reduced; the hydrogel monomer content is higher than 6mol/L, so that the hydrogel monomer is not easy to uniformly disperse, and the integrity of the pattern is also affected.

Preferably, the hydrogel monomer initiator comprises a benzophenone, a benzoyl, preferably 2, 2-diethoxyacetophenone and/or 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylpropionne; preferably, the hydrogel monomer initiator is contained in the hydrogel prepolymer solution in an amount of 0.05mg/mL to 3mg/mL, for example, 0.05mg/mL, 0.1mg/mL, 0.5mg/mL, 1.0mg/mL, 1.5mg/mL, 2mg/mL, 2.5mg/mL, 3mg/mL, etc., preferably 0.5mg/mL.

Initiators capable of initiating polymerization of the hydrogel monomers may be used, preferably 2, 2-diethoxyacetophenone and/or 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylpropionne; when the content of the hydrogel monomer polymerization initiator in the hydrogel prepolymer solution is lower than 0.05mg/mL, photopolymerization is incomplete; when the content of the hydrogel monomer polymerization initiator is higher than 3mg/mL, explosion polymerization easily occurs in the polymerization process, so that the polymerization is uneven, the mechanical strength is low, and the mechanical properties of the prepared surface patterning gel are affected.

Preferably, the hydrogel cross-linking agent comprises polyisocyanates, polyamines, polyols, glycidyl ethers, organic peroxides, silicones, metal organic compounds, inorganic substances, preferably inorganic nanoclay platelets and/or N, N-methylenebisacrylamide;

preferably, the hydrogel pre-polymer solution contains 1wt% to 16wt%, such as 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, preferably the hydrogel cross-linking agent is an inorganic nanoclay sheet containing 8wt% or 0.05wt% to 1wt% of N, N-methylenebisacrylamide, such as 0.05wt%, 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1wt%, preferably 0.4wt% of N, N-methylenebisacrylamide.

Crosslinking agents capable of crosslinking the hydrogel monomer may be used, preferably inorganic nanoclay platelets and/or N, N-methylenebisacrylamide; when the content of the hydrogel cross-linking agent in the hydrogel prepolymer is lower than 1wt%, the prepolymer has lower cross-linking degree, and the gel formation is adversely affected; when the content of the hydrogel crosslinking agent is more than 16wt%, the dispersion uniformity in water is poor, resulting in a decrease in the mechanical strength of the gel.

Preferably, the oleogel monomer hasStructure, wherein R is ₁ is-H, alkyl, R ₂ Is any one or the combination of at least two of alkyl, ester, ether and aromatic groups, and the number of carbon chains is 4-18; preferably, the oleogel monomer comprises acrylates and/or methacrylates.

The oil gel monomer is provided with a hydrophobic group, and the proper hydrophobic group is selected, so that the hydrophobic monomer can perform hydrophobic interaction with hydrophobic molecules modified on the surface of the substrate, and effective migration to a hydrophobic region of the substrate is realized, thereby ensuring clear and continuous boundaries of patterns and integrity of the patterns.

When the number of carbon chains in the oil gel monomer is less than 4, the hydrophobic interaction between the oil gel monomer and the modified hydrophobic molecule is not strong enough, and the defect of patterns is easily caused; when the number of carbon chains is more than 18, the oleogel monomer is solid at normal temperature, and is difficult to form stable emulsion with hydrogel prepolymerization liquid.

Preferably, the molar ratio of the oleogel monomer to hydrogel monomer is from 5:1 to 1:5, such as 5:1, 4:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:4, 1:5, preferably 2:1;

the proper oil/hydrogel monomer ratio is selected to enable the finally formed patterned gel to have good performance, the increase of the oil gel content can enable the mechanical performance of the oil-water gel to be improved, when the oil/hydrogel monomer ratio is less than 1:5, a complete oil film is difficult to induce to form in a hydrophobic area, and the mechanical performance of the gel is poor; when the ratio of the oil to the hydrogel monomer is greater than 5:1, the emulsion formed by the oil gel prepolymer and the hydrogel prepolymer is unstable and is susceptible to delamination before crosslinking is complete.

Preferably, the oleogel monomer initiator comprises a benzophenone, a benzoyl, preferably 2, 2-diethoxyacetophenone; the content of the oil gel monomer initiator in the oil gel prepolymer liquid is 0.02wt% to 0.3wt%, such as 0.02wt%, 0.05wt%, 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%, 0.3wt%, and preferably 0.08wt%;

initiators capable of initiating polymerization of the oleogel monomer may be used, preferably 2, 2-diethoxyacetophenone; when the content of the oil gel monomer polymerization initiator in the oil gel prepolymer is lower than 0.02wt%, photopolymerization is incomplete, and when the content of the oil gel monomer polymerization initiator is higher than 0.3wt%, explosion polymerization easily occurs in the polymerization process, so that polymerization is uneven, mechanical strength is low, and mechanical properties of the prepared surface patterning gel are affected.

Preferably, the oleogel cross-linking agent comprises polyisocyanates, polyamines, polyols, glycidyl ethers, organic peroxides, silicones, metal organic compounds, inorganic substances, preferably ethylene glycol dimethacrylate and/or polyethylene glycol dimethacrylate; preferably, the content of the oleogel cross-linking agent in the oleogel prepolymer liquid is 0.1wt% to 8wt%, for example 0.5wt%, 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt%, 5wt%, 5.5wt%, 6wt%, 6.5wt%, 7wt%, 8wt%, preferably 4wt%.

Crosslinking agents capable of crosslinking the oleogel monomer may be used, preferably ethylene glycol dimethacrylate and/or polyethylene glycol dimethacrylate; when the content of the oil gel cross-linking agent in the oil gel prepolymer is lower than 0.1wt%, the prepolymer has lower cross-linking degree, and the gel formation is adversely affected; at levels above 8wt% of oleogel cross-linking agent, the polymerized gel is brittle, resulting in a decrease in the mechanical strength of the patterned gel.

Preferably, the emulsion is obtained by emulsification with a power of 300W to 800W, e.g. 300W, 400W, 500W, 600W, 700W, 800W, preferably 585W, for an emulsification time of 0.5min to 3min, e.g. 0.5min, 1min, 1.5min, 2min, 2.5min, 3min, preferably 1min;

the emulsion is uniformly mixed and stabilized through the ultrasonic emulsification process, if the emulsification power is lower than 300W or the emulsification time is lower than 0.5min, the uniform stability of the emulsion is poor, and if the emulsification power is higher than 800W or the emulsification time is higher than 3min, the temperature of the solution is raised due to high ultrasonic power and long time, so that the solution is easy to volatilize.

Preferably, the gelation method in step (3) is a cross-linking polymerization, preferably an illumination power of 200W to 800W, for example 200W, 300W, 400W, 500W, 600W, 700W, 800W, preferably 500W, and a polymerization time of 10min to 60min, for example 10min, 20min, 30min, 40min, 50min, 60min.

The emulsion comprising hydrogel prepolymer and oleogel prepolymer is cross-linked and polymerized by irradiation with light to form a non-flowing gel, and the initiation power of the light is determined by the selected photoinitiator.

The size and dimension of the surface patterning gel are determined by the substrate, and different substrates are selected, so that gels with different dimensions (two-dimensional and three-dimensional) and different sizes can be prepared, and the surface patterning gel is a plane or a three-dimensional structure formed by one or more surfaces; preferably, the three-dimensional structure comprises any one or a combination of at least two of spheres, cylinders, prisms, cones or tables.

The dimension of the surface patterning gel is determined by the substrate, and when the patterning substrate is a plane, the prepared surface patterning gel is a sheet body with a two-dimensional structure; when the patterned substrate is a three-dimensional structure formed by one or more surfaces, emulsion is applied to the three-dimensional structure, then cross-linked and polymerized, and the patterned gel is prepared into a three-dimensional structure after being taken out of the three-dimensional structure. The size of the surface patterned gel is determined by the substrate and the gel size can range from microscopic (a few microns to hundreds of microns) to macroscopic (a few hundred microns to tens of centimeters).

The preparation method of the patterned substrate comprises the steps of carrying out hydrophilic treatment on the substrate to enable the surface of the substrate to have hydrophilic areas, and carrying out hydrophobic treatment on the substrate to enable the surface of the substrate to have hydrophobic areas.

Preferably, the hydrophilic treatment is an oxygen plasma treatment, preferably the oxygen plasma treatment time may be 4min to 15min, for example 4min, 5min, 6min, 7min, 8min, 9min, 10min, 11min, 12min, 13min, 14min, 15min, preferably 10min.

The surface of the cleaned substrate is modified with hydroxyl groups to be in a super-hydrophilic state by oxygen plasma treatment. If the oxygen plasma treatment time is less than 4min, the number of the surface modified hydroxyl groups is not large, and the surface hydrophilicity is not enough, so that the hydrophilic interaction force of the substrate and the hydrogel is weak, and the pattern can generate defects; the treatment time is longer than 15min, so that the adhesive tape, photoresist and the like on the surface of the substrate are easily damaged, and the modification effect is affected.

Preferably, the hydrophobic treatment is treatment of the region with a hydrophobic material; preferably, the hydrophobic material comprises fluorosilane molecules or silane molecules; preferably, the treatment method of the hydrophobic treatment comprises gas phase modification or liquid phase modification.

Modifying a hydrophobic material on the surface of the substrate through a gas phase or liquid phase condensation reaction to enable the surface of the substrate to be in a hydrophobic state, wherein the hydrophobic material comprises fluorosilane molecules, silane molecules or other molecules capable of enabling the surface to be modified into the hydrophobic state, and preferably the fluorosilane molecules comprise 1H, 2H-perfluoro decyl trimethoxy (triethoxy, trichloro) silane or 1H, 2H-perfluoro octyl trimethoxy (triethoxy, trichloro) silane; preferably, the silane molecule comprises any one of n-butyltrimethoxy (triethoxy, trichloro) silane, n-hexyltrimethoxy (triethoxy, trichloro) silane, n-octyltrimethoxy (triethoxy, trichloro) silane, dodecyltrimethoxy (triethoxy, trichloro) silane, hexadecyltrimethoxy (triethoxy, trichloro) silane or octadecyltrimethoxy (triethoxy, trichloro) silane.

Preferably, the time of the hydrophobic treatment is 3h to 10h, for example 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, further preferably 6h.

The gas phase/liquid phase condensation reaction is carried out by fluorosilane or silane molecules, so that the surface of the substrate is in a hydrophobic state. If the hydrophobic modification time is less than 3 hours, the surface modified hydrophobic molecules are not more, the surface hydrophobicity is not enough, the hydrophobic interaction is weaker, and the pattern of the patterned gel is defective; the treatment time is longer than 10 hours, and the hydrophobicity of the surface of the substrate is not further improved.

Preferably, the preparation method of the patterned substrate comprises a mask method and/or a step-by-step treatment method;

as an alternative solution, when the patterned substrate is a plane, a mask method is used to prepare the patterned substrate, and the mask method includes the following steps:

(a) Carrying out hydrophilic treatment and hydrophobic treatment on the surface of the substrate;

(b) Placing a mask on the surface of the substrate according to a preset pattern, and only exposing a preset hydrophilic area;

(c) Performing hydrophilic treatment on the exposed preset hydrophilic area;

(d) The mask is removed to form a patterned substrate having hydrophilic and hydrophobic regions.

As a further alternative, when the patterned substrate is a plane, a mask method is used to prepare the patterned substrate, and the mask method may further include the following steps:

(a') subjecting the surface of the substrate to a hydrophilic treatment;

(b') placing a mask on the surface of the substrate according to a preset pattern, and exposing only preset hydrophobic areas;

(c') subjecting the exposed predetermined hydrophobic region to a hydrophobic treatment;

(d') removing the mask to form a patterned substrate having hydrophilic and hydrophobic regions.

Preferably, the mask material includes tape, photoresist or other material that can create exposed patterned areas on the surface of the substrate, and to obtain a higher precision pattern on the substrate, photoresist is preferably used as the mask material.

Preferably, the mask may be prepared by the following method: uniformly and lightly pasting a layer of adhesive tape (without bubbles) on the surface of the substrate or spin-coating a layer of photoresist, drawing a specific pattern by using drawing software, marking the pattern on the adhesive tape or the photoresist by using a laser marking machine, exposing the pattern, and tearing off the residual adhesive tape or washing the residual photoresist after the construction of the hydrophilic/hydrophobic area on the surface is completed, thereby forming the substrate with the preset pattern.

Preferably, the hydrophilic region and the hydrophobic region are located on the same surface of the substrate; placing a second substrate opposite the hydrophilic and hydrophobic regions of the patterned substrate and adding a spacer between the two substrates to maintain a gap between the two substrates prior to applying the emulsion to the substrate surface in step (2); dripping the emulsion into the gaps until the whole gaps are filled; and then carrying out cross-linking polymerization on the emulsion to obtain the gel with the patterned surface.

Preferably, the thickness of the spacer is 200 μm to 3mm, preferably 1mm.

As a preferred technical solution, when the patterned substrate is a three-dimensional structure composed of one or more surfaces, the patterned substrate is prepared using a step-by-step process comprising the steps of:

And splitting the substrate according to a preset pattern, respectively carrying out hydrophilic treatment and/or hydrophobic treatment, and then assembling the split substrate according to the preset pattern. Preferably, the substrate is a three-dimensional structure with an internal space, preferably a mold with an internal surface, the mold is split into at least two parts, the internal surfaces of the parts are respectively subjected to hydrophilic treatment and/or hydrophobic treatment, then the split molds are combined to form a mold with the internal space, the internal surfaces of the mold are patterned by hydrophilic areas and hydrophobic areas, gel emulsion is poured into the mold for polymerization, and then the mold is taken out, so that the three-dimensional structure of the patterned gel can be obtained.

It is a second object of the present invention to provide a surface patterned gel having a first surface region and a second surface region of different wettability;

preferably, the surface-patterned gel is prepared by the preparation method as set forth in object one;

preferably, the contact angle of the first surface area is 65-120 degrees, and the contact angle of the second surface area is 5-45 degrees;

preferably, the first surface region is enriched with lipophilic groups and the second surface region is enriched with hydrophilic groups;

Preferably, the lipophilic group comprises any one or a combination of at least two of alkyl, ester, ether, and aromatic groups;

preferably, the hydrophilic group includes any one or a combination of at least two of an amide group, a carboxyl group, a hydroxyl group, and an amino group.

The first surface area of the surface patterned gel is an oil gel area, is enriched with lipophilic groups and corresponds to the hydrophobic area of the patterned substrate, and the hydrophobic monomers in the emulsion directionally move to the hydrophobic area of the substrate due to hydrophobic interaction; the second surface region is a hydrogel region enriched with hydrophilic groups, and corresponds to the hydrophilic region of the patterned substrate, because the hydrophilic monomers in the emulsion directionally move to the hydrophilic region of the substrate through hydrophilic interaction.

Preferably, the depth of each of the first and second surface regions is independently selected from 4 μm

～20μm。

Since the hydrophilic/hydrophobic induction effect exists only at the solid/liquid interface, the directional movement of the hydrophilic monomer and the hydrophobic monomer does not occur in the emulsion liquid phase, so that after the emulsion is gelled, the hydrophilic/hydrophobic pattern exists only at the surface of the gel, and the depth of the pattern is independently selected from 4-20 mu m. The thickness of the gel has no effect on the surface patterning, and the patterning of the gel only occurs at the surface, regardless of the thickness of the gel.

The third object of the present invention is to provide a use of the surface-patterned gel according to the second object, wherein the surface-patterned gel is used for any one or a combination of at least two of pattern transfer, detection of DNA molecules and/or fluorescent molecules, anisotropic adhesion.

Applying a water-soluble dye or an oil-soluble dye on the surface of the surface-patterned gel, which can be used for pattern transfer; dripping a solution with DNA molecules and/or fluorescent molecules into a hydrophilic area of the surface patterned gel, wherein the solution can be used for detecting the DNA molecules and/or the fluorescent molecules; making at least one region of the surface patterned gel surface a hydrogel and at least one region an oleogel, an anisotropic adhesive material may be prepared due to the viscosity difference of the oleogel and the hydrogel.

The fourth object of the present invention is to provide a pattern transfer stamp, which includes the surface patterning gel according to the second object, wherein the first surface area and the second surface area of the surface patterning gel are on the same surface;

preferably, in the pattern transfer stamp, the second surface region of the surface patterning gel absorbs water-soluble dye and/or the first surface region of the surface patterning gel absorbs oil-soluble dye.

In the pattern transfer stamp, the first surface area of the surface patterning gel is a hydrophobic area and therefore can only be dyed by the oil-soluble dye, and the second surface area is a hydrophilic area and therefore can only be dyed by the water-soluble dye, and by applying the water-soluble dye and/or the oil-soluble dye of different colors, the surface of the gel can present a preset pattern and can be used for pattern transfer.

The fifth object of the present invention is to provide a method for using the pattern transfer stamp according to the fourth object, the method comprising the steps of:

covering the surface of the pattern transfer seal with hydrogel prepolymer, irradiating with ultraviolet light to polymerize the hydrogel prepolymer, and stripping the polymerized gel from the transfer seal after polymerization to realize pattern transfer.

Preferably, the hydrogel pre-polymerization solution comprises a hydrogel monomer dispersed in water, a hydrogel monomer initiator, and a hydrogel cross-linking agent.

And applying hydrogel prepolymerization liquid on the surface of the pattern transfer seal, wherein in the process of polymerizing the hydrogel prepolymerization liquid by ultraviolet irradiation, water-soluble dye on the surface of the seal is diffused into the inner surface of a corresponding area of the hydrogel, and the polymerized hydrogel is peeled off from the transfer seal to realize pattern transfer.

Compared with the prior art, the invention has the following beneficial effects:

(1) According to the invention, the emulsion containing the hydrogel prepolymer liquid and the oil gel prepolymer liquid is selected as the precursor of the patterning gel, the directional migration of the hydrogel monomer and the oil gel monomer in the emulsion is realized by utilizing the difference of wettability of the substrate surface and the induction effect of the interface hydrophilic/hydrophobic interaction, the patterning of the gel surface can be realized directly by a infiltration transfer method, the preparation process is simple and feasible, and complex equipment is not required.

(2) In the preferred technical scheme, the proper hydrogel monomer and the proper oleogel monomer, and the composition and the proportion of the hydrogel prepolymer liquid and the oleogel prepolymer liquid are selected, so that the directional induction and transfer of the interface are complete, and the prepared patterned gel has clear pattern boundary and high precision.

(3) In the preferred technical scheme, the surface patterning gel prepared by selecting proper emulsion composition and proportion and controlling the emulsification and polymerization conditions has excellent mechanical properties, swelling resistance, stretchability and other properties, so that the application of the surface patterning gel in various scenes is possible.

(4) Because the hydrophilic/hydrophobic interaction induction effect only exists at the solid/liquid interface, the invention can prepare the gel with the surface patterned, the gel phase is not patterned, the overall thickness of the gel does not influence the surface patterned, and the gel patterned only occurs on the surface no matter how thick the gel is. That is, the patterned gel prepared by the invention has no change in gel phase except the patterned surface, the overall performance of the gel is not affected by the patterning process, and the non-patterned surface is not affected when used for other purposes.

(5) The size and the dimension of the surface patterning gel prepared by the invention are adjustable and controllable, and by changing the shape or the structure of the substrate, the gel with a two-dimensional structure with any pattern or shape can be prepared, and the three-dimensional gel with any shape can also be prepared. Gel pattern sizes can range from microscopic (a few microns to hundreds of microns) to macroscopic (a few hundreds of microns to tens of centimeters).

(6) The preparation method of the patterned gel is applicable to various gels and has wide application range.

(7) The surface patterning gel prepared by the invention is suitable for various application scenes, can be used as a transfer seal for pattern transfer, can be used as a detection platform for detecting the intensity of DNA molecules and fluorescent molecules, can also be used for anisotropic adhesion, and has very wide application prospect.

(8) After the surface patterning gel prepared by the method is stretched, the conditions such as pattern fracture and the like can not occur, the integrity and the continuity of the pattern can still be maintained, and after the transfer printing process, the stretched pattern can be obtained on the surface of the hydrogel.

Drawings

FIG. 1 is a comparison of clarity of surface patterned gel patterns prepared from different monomers of the present application;

FIG. 2 is a graph showing the wettability of oil/hydrogel areas on a surface of a patterned gel of the present application;

FIG. 3 is a graph showing the effect of thickness of a surface patterned gel sample of the present application on surface patterning;

FIG. 4 is a graph showing the swelling resistance of the surface patterned gel prepared herein;

FIG. 5 is a graph showing the tensile properties of the surface patterned gel prepared herein;

FIG. 6 is a graph showing the transferability of a surface patterned gel pattern prepared according to the present application;

FIG. 7 is a drawing of a surface patterned gel prepared herein after being stretched and transferred to a stretched pattern;

FIG. 8 is a graph showing the detection performance of fluorescent molecules by the surface patterned gel pattern prepared herein;

FIG. 9 is a macroscopic 3D hydrogel pattern prepared in accordance with the present application;

FIG. 10 is a macroscopic hydrogel pattern (a) and oleogel pattern (b) prepared herein;

FIG. 11 is a microscopic hydrogel pattern (a) and oleogel pattern (b) prepared herein;

FIG. 12 is a composite pattern of macroscopic hydrogels and oleogels prepared herein.

Detailed Description

The technical scheme of the application is further described through the following specific embodiments.

It should be apparent to those skilled in the art that the examples are merely provided to aid in understanding the present application and should not be construed as limiting the present application in any way.

Example 1

A method of preparing a gel having a surface pattern, the method comprising the steps of:

(1) Providing a patterned substrate having hydrophilic and hydrophobic regions on a surface, the patterned substrate being prepared by:

(1-1) treating the cleaned glass sheet with oxygen plasma for 10min at a power of 160W to modify hydroxyl groups on the surface of the glass sheet to be in a super-hydrophilic state; then, through gas phase or liquid phase condensation reaction, modifying fluorosilane on the surface of the glass sheet, wherein the fluorosilane is 1H, 2H-perfluoro decyl trimethoxy silane, so that the glass sheet is in a hydrophobic state;

(1-2) uniformly and lightly attaching a layer of adhesive tape to the hydrophobic surface of the glass sheet;

(1-3) drawing a specific pattern by drawing software, marking the pattern on the adhesive tape by a laser marking machine, and tearing off the adhesive tape at the place with the pattern; then oxygen plasma treatment is carried out for 10min, the power is 160W, the area without the adhesive tape (torn off) is in a super-hydrophilic state, and the area covered by the adhesive tape is still in a hydrophobic state;

(1-4) tearing off the residual adhesive tape to obtain the patterned substrate with the hydrophilic area and the hydrophobic area on the surface;

(2) Applying an emulsion comprising a hydrogel pre-polymerization solution and an oil gel pre-polymerization solution to the surface of the patterned substrate, wherein hydrophilic monomers and hydrophobic monomers in the pre-polymerization solution self-assemble on the surface of the substrate; preparing hydrogel prepolymer: adding 0.15mol of hydrogel monomer acrylamide, 4.8g of cross-linking agent nanoclay and 30mg of photoinitiator 2, 2-diethoxyacetophenone into 60mL of water, and dispersing to obtain hydrogel prepolymer;

preparing an oil gel prepolymer: mixing 0.3mol of oil gel monomer lauryl methacrylate, 3g of cross-linking agent ethylene glycol dimethacrylate and 60mg of photoinitiator 2, 2-diethoxyacetophenone;

mixing hydrogel prepolymerization solution and oleogel prepolymerization solution according to the mol ratio of oleogel monomer to hydrogel monomer of 2:1, and emulsifying for 1min under 585W power to obtain stable emulsion;

dripping the obtained emulsion between a patterned glass sheet and another common glass sheet, separating the glass sheets by using a gasket, and self-assembling a hydrogel monomer and an oil gel monomer in the prepolymerization solution on the bottom surface of the patterned glass sheet;

(3) Gelling the emulsion and peeling off the emulsion from the substrate to obtain a gel with patterning;

And (3) carrying out ultraviolet irradiation polymerization on the oil-water gel emulsion, wherein the ultraviolet irradiation polymerization power is 500W, the photopolymerization time is 30min, and stripping the gel after cross-linking polymerization from the substrate to obtain the gel with the pattern.

Examples 2 to 7

The only difference from example 1 is the choice of hydrogel monomer or oleogel monomer.

The hydrogel monomer in example 2 was 0.15mol of hydroxyethyl acrylate.

The hydrogel prepolymer in example 3 was composed of 0.15mol of acrylic acid, 21.3mL of water, 31.5mL of a 4wt% strength by mass polyvinyl alcohol solution, 121.3mg of N, N-methylenebisacrylamide, 126mg of 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylpropenone. This is because negatively charged acrylic acid cannot be crosslinked by the nanoclay sheet in example 1, and thus a crosslinking agent needs to be replaced, in which a 4wt% polyvinyl alcohol solution can be used as an emulsion stabilizer while improving the mechanical strength of the hydrogel.

The hydrogel monomer in example 4 was 0.15mol of N, N-dimethylacrylamide.

The oleogel monomer in example 5 was 42.7g butyl methacrylate.

The oleogel monomer in example 6 was 51.1g hexyl methacrylate.

The oleogel monomer in example 7 was 59.5g isooctyl methacrylate.

Examples 8 to 15

The only difference from example 1 is the monomer content, initiator type and content, and crosslinker type and content in the hydrogel prepolymer.

The content of the monomer in the hydrogel prepolymer in example 8 was 0.06mol.

The content of the monomer in the hydrogel prepolymer in example 9 was 0.36mol.

The content of the photoinitiator in the hydrogel prepolymer in example 10 was 3mg.

The content of the photoinitiator in the hydrogel prepolymer in example 11 was 180mg.

The type of photoinitiator in the hydrogel prepolymer in example 12 was 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylpropionacetone, and the content was 60mg.

The content of the crosslinking agent in the hydrogel prepolymer in example 13 was 0.6g.

The content of the crosslinking agent in the hydrogel prepolymer in example 14 was 9.6g.

The type of the crosslinking agent in the hydrogel prepolymer in example 15 was N, N-methylenebisacrylamide, and the content thereof was 240mg.

Examples 16 to 22

The only difference from example 1 is the monomer content, initiator type and content, crosslinker type and content in the oleogel prepolymer.

The mole ratio of oleogel monomer to hydrogel monomer in example 16 was 5:1.

The mole ratio of oleogel monomer to hydrogel monomer in example 17 was 1:5.

The content of photoinitiator in the oleogel prepolymer solution in example 18 was 0.02wt%.

The content of photoinitiator in the oleogel prepolymer solution in example 19 was 0.3wt%.

The content of the crosslinking agent in the oleogel prepolymer liquid in example 20 was 0.1% by weight.

The content of the crosslinking agent in the oleogel prepolymer liquid in example 21 was 8% by weight.

The type of the crosslinking agent in the oleogel prepolymer in example 22 was polyethylene glycol dimethacrylate, and the content was 4wt%.

Examples 23 to 28

The only difference from example 1 is the choice of patterning substrate processing conditions including oxygen plasma processing time, hydrophobic molecule selection, hydrophobic processing time.

The treatment time of the oxygen plasma in example 23 was 4min.

The treatment time of the oxygen plasma in example 24 was 15min.

The molecule used for the hydrophobic modification in example 25 was n-octyl trimethoxysilane.

The molecule used for the hydrophobic modification in example 26 was hexadecyltrimethoxysilane.

The time for hydrophobically modifying the substrate surface in example 27 was 2h.

The time for hydrophobically modifying the substrate surface in example 28 was 12h.

Examples 29 to 30

The only difference from example 1 is the choice of the photopolymerization conditions.

In example 29, the UV power was 200W and the polymerization time was 60min.

In example 30, the UV power was 800W and the polymerization time was 10min.

Example 31

The three-dimensional gel is prepared by using a three-dimensional mold, wherein the three-dimensional mold is a sphere and a cylinder.

Comparative example 1

The only difference from example 1 is that a patterned gel cannot be formed using a solution of an aqueous gel monomer and an oleogel monomer instead of an emulsion.

Comparative example 2

The only difference from example 1 is that only hydrogel was used, and no surface-patterned gel could be obtained.

Application example 1

The gels obtained in examples and comparative example 1 were prepared into pattern transfer seals. Comparative example 1 failed to form a surface patterned gel, and thus no application example experiment was performed.

Application example two

The surface patterning gel obtained in example 1 was prepared into a pattern transfer stamp, and the stamp was stretched and then transferred with a pattern.

Application example III

The surface patterned gel obtained in example 1 is used for detecting fluorescent molecules, DNA molecules to be detected with different concentrations are combined with probes through base complementation pairing, fluorescent signal amplification is realized, the solution is dripped into a surface hydrogel area of the patterned gel, and fluorescent intensity of DNA reaction solutions with different concentrations to be detected is detected under the same detection condition by using a fluorescent confocal microscope.

Performance test:

(1) Contact angle: the contact angle of the first surface region and the contact angle of the second surface region of the surface-patterned gel obtained in example, and the contact angle of the hydrogel surface of comparative example 2 were measured;

the testing method comprises the following steps: after polymerization of all samples was completed, the contact angle of the surfaces (first and second surfaces) was measured at room temperature using a germany Dataphysics OCA20 instrument, with a drop volume controlled to 2uL.

(2) Pattern definition: and (3) dropwise adding a water-soluble dye to the surface of the patterned gel obtained in the embodiment for dyeing, wherein the sum of the redundant part area and the missing part area of the first area is calculated to be A, when A is smaller than 5%, the pattern definition is recorded as excellent, and when A is 5% -10%, the pattern definition is recorded as good.

(3) Mechanical properties (tensile properties): the surface patterned gels obtained in examples and comparative example 2 were tested for mechanical properties.

The testing method comprises the following steps: the gel sample was cut into strips (length 6cm, width 1cm, thickness 2 mm) and subjected to a tensile test. All experiments were carried out using a Mark-10 ESM301 electric bench, in which one end of the strip was clamped by a clamp during the test, and stretched upward at a speed of 20mm/min, and stress and strain data during the stretching were recorded, and the ratio of stress to strain at a strain of 10% was calculated.

(4) Swelling resistance: the surface patterned gels obtained in the examples and comparative examples were tested for swelling resistance.

The testing method comprises the following steps: the surface patterned gel was cut to a size of 1cm x 1cm, and the middle of the surface of each gel sheet had a five-pointed star hydrogel pattern (initial length of 0.6 cm). The hydrogel pattern area is dyed into blue by methylene blue, then is soaked in different solvents for 5 hours, and is taken out, and a camera is used for photographing and measuring the length change of front and rear five-pointed star. The algorithm of the swelling ratio is as follows: q=l/L ₀ X 100%; wherein L is the length of the five-pointed star after swelling, L ₀ Is the initial length of the five-pointed star.

(5) Transferability: the surface patterned gels obtained in the examples and comparative examples were tested for transferability.

The testing method comprises the following steps: applying hydrogel prepolymerization liquid on the surface of the patterned gel for locally absorbing dye molecules, irradiating with ultraviolet light for 5-10 min to polymerize the hydrogel prepolymerization liquid, so that the dye molecules on the surface of the transfer seal have enough time to transfer at a solid/liquid interface, and finally stripping the polymerized gel from the transfer seal. The patterned gel surface is transferable if the pattern is completely transferred to the hydrogel surface; otherwise, there is no transferability.

(6) Fluorescent molecule detection sensitivity: the surface patterned gel obtained in example 1 was tested for fluorescent molecule detection concentration.

The testing method comprises the following steps: combining DNA molecules to be detected with different concentrations with probes through base complementation pairing and realizing fluorescent signal amplification, dripping the solution into a surface hydrogel region of patterned gel, detecting fluorescent intensity of DNA reaction solutions with different concentrations to be detected under the same detection condition by using a fluorescent confocal microscope, calculating a fitted standard curve, and obtaining a correlation coefficient.

The test results are shown in Table 1:

TABLE 1

As can be seen from table 1, by the method for preparing a gel with surface patterning of the present application, an emulsion comprising a hydrogel pre-polymerization solution and an oil gel pre-polymerization solution is applied to the surface of a patterned substrate with hydrophilic and hydrophobic regions, and the hydrogel monomer and the oil gel monomer in the pre-polymerization solution are self-assembled on the surface of the substrate, so that the gel with surface patterning can be obtained. By adjusting the contents and types of hydrogel monomers, oleogel monomers, initiators and cross-linking agents, and adjusting the substrate treatment time, hydrophobic materials and emulsion polymerization conditions, the corresponding products expected to be obtained can be obtained.

1. As is clear from comparative examples 1 to 4, the stronger the hydrophilic interaction between the hydrogel monomer and the hydrophilic group of the hydrophilic region on the surface of the substrate, the better the pattern definition is obtained, as shown in FIG. 1 (a) which is the patterned gel obtained in example 1, FIG. 1 (b), FIG. 1 (c), and FIG. 1 (d) which are the patterned gels obtained in examples 2, 3, and 4, respectively, the better the pattern definition is obtained by the hydrogel monomer Acrylamide (AM), hydroxyethyl acrylate (HEA), and Acrylic Acid (AA), the hydrophilicity of the hydrogel monomer N, N-Dimethylacrylamide (DMA) monomer is not as strong as the three hydrogel monomers, the weak interface induction is obtained, and thus the pattern will be defective, and the pattern definition is good.

2. As is clear from comparative examples 5 to 7, the greater the number of the chain length of the oleogel monomer is in the range of 4 to 18, the better the pattern definition is, as shown in FIG. 1 (e), FIG. 1 (f) and FIG. 1 (g) which are the patterned gels obtained in examples 5, 6 and 7, respectively, the better the pattern definition is produced by the oleogel monomer Hexyl Methacrylate (HMA) and 2-methyl hexyl methacrylate (EMA), the hydrophobic chain of the oleogel monomer n-Butyl Methacrylate (BMA) is not longer than the two oleogel monomers, the hydrophobic interaction is weak, and the interface induction is weak, so that the pattern will generate defects, and the pattern definition is good.

3. As is clear from comparative examples 8 to 15, the hydrogel monomer, initiator and crosslinking agent contents in the hydrogel prepolymer are selected within the scope of the present invention, and a uniform and stable emulsion can be prepared, and the definition of the surface patterned gel pattern prepared by the method of the present invention is excellent.

4. As is clear from comparative examples 16 to 22, the content of the oleogel monomer, the initiator and the crosslinking agent in the oleogel prepolymer is selected within the scope of the present invention, so that a uniform and stable emulsion can be prepared, and the definition of the surface patterned gel pattern prepared by the method of the present invention is excellent.

5. As is known from comparative examples 23 to 28, the selection of suitable substrate treatment conditions can make the substrate have better hydrophilicity/hydrophobicity, the substrate and the hydrogel can generate hydrophilic/hydrophobic induction effect, the oxygen plasma treatment time is short, the surface modified hydroxyl groups are few, the hydrophilic interaction force is weak in comparative example 23, and therefore, defects can be generated in the pattern, and the pattern definition is good. In comparative example 27, the hydrophobic modification time was short, the surface modified hydrophobic molecules were few, and the hydrophobic interaction force was weak, so that defects were generated in the pattern, and the pattern definition was good.

6. As is clear from comparative examples 29 to 30, the emulsion can be crosslinked to form a gel having a certain mechanical strength by selecting the light power and the polymerization time according to the photoinitiator within the scope of the present invention, and the pattern definition of the surface patterned gel prepared by the method of the present invention is excellent.

7. As is known from comparative example 31, a three-dimensional patterned gel was prepared by the method of the present invention using a three-dimensional mold, and as shown in fig. 9, the three-dimensional patterned gel was a sphere and a cylinder, in which a dark portion was a dyed hydrogel region and a light portion was an undyed oil gel region.

8. The surface patterned gels obtained in examples 1-31 herein formed hydrophilic and hydrophobic regions, the contact angles of the first and second surface regions are shown in table 1, fig. 2 shows the wettability characterization of example 1, with the upper graph showing the contact angle of the patterned gel first surface region (hydrophobic region) and the lower graph showing the contact angle of the second surface region (hydrophilic region).

9. The thickness of the surface patterning gel sample obtained in the application has no influence on surface patterning, no matter how thick the sample thickness is, the gel patterning only occurs on the surface of the gel, and fig. 3 shows the surface patterning gel obtained in example 1, and the gel thickness is 1mm, 2mm and 2.5mm from top to bottom in sequence.

10. The patterned gels obtained in examples 1 and 23-31 of the present application have a maximum swelling ratio of 110% or less in different solvents, and the patterned gels obtained in examples 2-22 have a maximum swelling ratio of 120% or less in different solvents, and all have excellent swelling resistance, and fig. 4 shows the swelling resistance characterization of example 1, in which the ordinate direction is the swelling ratio of the surface patterned gel in different solvents, and the upper pentagram pattern is the hydrogel region of the corresponding surface patterned gel.

11. The mechanical properties of the surface patterning gels obtained in examples 1-31 of the present application are shown in table 1, and all have certain stretchability, and the surface patterning gel will not break or break when the strain is 10%, so that the surface patterning gel can be used for transfer seals or other uses; the patterned gel obtained in examples 1, 4, 8, 9, 12, 16, 17, 22-30 has repeatable stretchability, good gel elasticity and can bear large deformation continuously; FIG. 5 shows the reciprocating tensile property characterization of example 1.

12. The pattern transfer stamps prepared in application examples 1-30 of the present application all have pattern transferability, and fig. 6 (a) - (c) show transfer performance characterization of application example 1, and fig. 6 (a) shows prepared surface patterning gel, (b) shows surface patterning hydrogel obtained by using hydrogel as receiving medium, and the pattern can be completely transferred onto the surface of hydrogel according to the ratio of 1:1, and (c) shows that after water flow impact for 60s, the pattern does not generate any defect, and the transferred pattern is very stable.

13. The pattern transfer stamp manufactured by the application example of example 1 of the present application still can realize pattern transfer after stretching to obtain a stretched pattern, and fig. 7 (a) - (d) show the stretch transfer performance characterization of the application example of example 1, and fig. 7 (a) shows the prepared surface patterning gel, (b) shows the surface patterning gel obtained after stretching the surface patterning gel, (c) shows the surface patterning hydrogel obtained by using the hydrogel as a receiving medium, and the stretched pattern can be completely transferred to the surface of the hydrogel according to the ratio of 1:1, and d) shows that no defect is generated in the pattern after water flow impact for 60s, and the transferred pattern is quite stable.

14. The surface patterned gel obtained in example 1 was used for detecting fluorescent molecule concentration, and has high detection sensitivity, R ² = 0.99554, fig. 8 shows a representation of the surface patterned gel of example 1 for fluorescent molecular concentration detection, with the left plot from left to right for the fluorescence enrichment process over time (0 s-150 s).

15. Macroscopic and microscopic surface patterned gels can be prepared using the methods of the present application, FIG. 10 is a macroscopic hydrogel pattern and oleogel pattern prepared in example 1, wherein the dark portions in FIG. 10 (a) are the dyed hydrogel areas and the white portions are the undyed oleogel areas; the dark portions in fig. 10 (b) are the stained oleogel areas, and the white portions are the undyed hydrogel areas. FIG. 11 shows a microscopic hydrogel pattern and an oleogel pattern, the patterned portion in FIG. 11 (a) being a fluorescence-stained hydrogel region and the unpatterned portion being an undyed oleogel region; in FIG. 11 (b), the structural part is a fluorescent-stained oleogel region, and the remaining part is an undyed hydrogel region. It can be seen that the method of the present application gives a surface patterned gel with high pattern definition in both macroscopic and microscopic dimensions.

16. By adopting a gradual dyeing process and utilizing dyes with different colors and properties, the method can also carry out regional accurate dyeing on the gel with complex patterns on the surface, and fig. 12 is a macroscopic hydrogel and oil gel composite pattern prepared by using the embodiment 1, wherein the dark color part is a hydrogel region, the light color part is an oil gel region and the white part is an oil gel region. It can be seen that the surface patterned gel pattern has high definition, and the lines of the pattern are complete and clear.

The surface patterning gel dyeing process comprises the following steps:

dyeing process of the first surface region: spraying a layer of water film on the surface of the gel after polymerization is finished to protect a second surface area, then dripping oil-soluble dye on the surface of the gel, and only the first surface area can absorb dye molecules and be dyed; after 5min, residual liquid on the gel surface was removed, and the first surface area of the patterned gel was successfully stained.

Dyeing process of the second surface region: placing the polymerized gel sample under oil (n-decane) to protect a first surface area, dropwise adding water-soluble dye on the surface of the gel, and only a second surface area can absorb dye molecules and be dyed; after 5min, the gel was removed from the oil and the surface residual liquid was removed, allowing the second surface area of the patterned gel to be successfully stained.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.

Claims

1. A method of preparing a gel having a surface pattern, the method comprising the steps of:

(2) Applying an emulsion comprising a hydrogel prepolymerization solution and an oil gel prepolymerization solution to the surface of the patterned substrate, wherein a hydrogel monomer and an oil gel monomer in the prepolymerization solution self-assemble on the surface of the substrate;

(3) After the emulsion polymerization is completed and peeled from the substrate, a gel with a pattern is obtained;

in the hydrogel prepolymerization solution, the content of hydrogel monomers is 1 mol/L-6 mol/L; the hydrogel monomer hasA structure, wherein R is a hydrophilic group, and the hydrophilic group comprises any one or a combination of at least two of an amide group, a carboxyl group, a hydroxyl group and an amino group; the oleogel monomer has->Structure, wherein R is ₁ is-H, alkyl, R ₂ Is an ester group, and the number of carbon chains is 4-18.

2. The method of manufacture of claim 1, wherein the emulsion comprises an oil-in-water emulsion or a water-in-oil emulsion.

3. The method according to claim 1, wherein the emulsion is obtained by mixing and emulsifying the hydrogel prepolymer and the oleogel prepolymer.

4. The method of preparing according to claim 1, wherein the hydrogel pre-polymerization solution comprises a hydrogel monomer dispersed in water, a hydrogel monomer initiator, and a hydrogel cross-linking agent; the oil gel pre-polymerization liquid comprises an oil gel monomer, an oil gel monomer initiator and an oil gel cross-linking agent.

5. The method of claim 1, wherein the hydrogel monomer comprises any one or a combination of at least two of acrylamide, acrylic acid, and hydroxyethyl acrylate.

6. The method according to claim 1, wherein the content of the hydrogel monomer in the hydrogel prepolymer is 2.5mol/L.

7. The method of claim 4, wherein the hydrogel monomer initiator comprises a benzophenone compound and a benzoyl compound.

8. The method of preparation of claim 4, wherein the hydrogel monomer initiator comprises 2, 2-diethoxyacetophenone and/or 2-hydroxy-4' - (2-hydroxyethoxy) -2-methylpropionne.

9. The method according to claim 4, wherein the content of the hydrogel monomer initiator in the hydrogel prepolymer is 0.05 mg/mL-3 mg/mL.

10. The method according to claim 4, wherein the content of the hydrogel monomer initiator in the hydrogel prepolymer solution is 0.5mg/mL.

11. The method of claim 4, wherein the hydrogel cross-linking agent comprises polyisocyanates, polyamines, polyols, glycidyl ethers, organic peroxides, silicones, metal-organic compounds, and inorganic compounds.

12. The method of claim 4, wherein the hydrogel cross-linking agent comprises inorganic nanoclay platelets and/or N, N-methylenebisacrylamide.

13. The method according to claim 4, wherein the hydrogel prepolymer is prepared with a content of the hydrogel cross-linking agent of 1 to 16wt% or 0.05 to 1wt% of N, N-methylenebisacrylamide.

14. The method of claim 13, wherein the hydrogel cross-linking agent is an inorganic nanoclay sheet in an amount of 8wt% or an N, N-methylenebisacrylamide in an amount of 0.4wt% in the hydrogel pre-polymerization solution.

15. The method of any one of claims 1 to 14, wherein the oleogel monomer comprises acrylates and/or methacrylates.

16. The method of any one of claims 1 to 14, wherein the molar ratio of oleogel 9 monomer to hydrogel monomer is from 5:1 to 1:5.

17. The method of claim 16, wherein the mole ratio of oleogel monomer to hydrogel monomer is 2:1.

18. The method of claim 4, wherein the oleogel monomer initiator comprises a benzene ketone, a benzoyl group.

19. The method of preparation of claim 4, wherein the oleogel monomer initiator comprises 2, 2-diethoxyacetophenone.

20. The method according to claim 4, wherein the content of the oleogel monomer initiator in the oleogel prepolymer is 0.02wt% to 0.3wt%.

21. The method of claim 20, wherein the oleogel monomer initiator is present in the oleogel prepolymer solution in an amount of 0.08wt%.

22. The method of claim 4, wherein the oil gel cross-linking agent comprises polyisocyanates, polyamines, polyols, glycidyl ethers, organic peroxides, silicones, metal organic compounds, and inorganic substances.

23. The method of claim 4, wherein the oleogel cross-linking agent comprises ethylene glycol dimethacrylate and/or polyethylene glycol dimethacrylate.

24. The method according to claim 4, wherein the content of the oil gel cross-linking agent in the oil gel prepolymer is 0.1wt% to 8wt%.

25. The method of claim 24, wherein the oil gel pre-polymer solution contains 4wt% of the oil gel cross-linking agent.

26. The process according to any one of claims 1 to 14, 17 to 25, wherein the emulsion is obtained by emulsification with a power of 300W to 800W and a time of 0.5min to 3min.

27. The method according to any one of claims 1 to 14 and 17 to 25, wherein the gelation method in step (3) is a cross-linking polymerization.

28. The method of claim 27, wherein the gelation process of step (3) is photopolymerization.

29. The method of claim 28, wherein the light power is 200W to 800W and the polymerization time is 10min to 60min.

30. The method of any one of claims 1 to 14, 17 to 25, wherein the patterned substrate is a planar surface or a three-dimensional structure comprising one or more surfaces.

31. The method of claim 30, wherein the three-dimensional structure comprises any one or a combination of at least two of spheres, cylinders, prisms, cones, or tables.

32. The method of any one of claims 1 to 14, 17 to 25, wherein the patterned substrate is prepared by hydrophilizing the substrate to provide hydrophilic regions on the substrate surface and hydrophobically treating the substrate to provide hydrophobic regions on the substrate surface.

33. The method of claim 27, wherein the patterned substrate is prepared by hydrophilizing the substrate to provide hydrophilic regions on the substrate surface and hydrophobically treating the substrate to provide hydrophobic regions on the substrate surface.

34. The method of any one of claims 28 to 29, wherein the patterned substrate is prepared by hydrophilizing the substrate to provide hydrophilic regions on the substrate surface and hydrophobically treating the substrate to provide hydrophobic regions on the substrate surface.

35. The method of claim 32, wherein the method of preparation comprises a mask process and/or a step-wise process.

36. The method of claim 33, wherein the method of preparation comprises a mask process and/or a step-wise process.

37. The method of claim 34, wherein the method of preparation comprises a mask process and/or a step-wise process.

38. The method according to any one of claims 32 to 37, wherein the stepwise treatment is a method of dividing the substrate according to a predetermined pattern, subjecting the divided substrate to hydrophilic treatment and/or hydrophobic treatment, respectively, and then assembling the divided substrate according to a predetermined pattern.

39. The method according to any one of claims 32 to 37, wherein the hydrophilic treatment is an oxygen plasma treatment.

40. The method of claim 39, wherein the oxygen plasma treatment time is 4 to 15 minutes.

41. The method of claim 40, wherein the oxygen plasma treatment time is 10 minutes.

42. The method of any one of claims 32 to 37, wherein the hydrophobic treatment is treatment of the region with a hydrophobic material.

43. The method of claim 42, wherein the hydrophobic material comprises fluorosilane molecules or silane molecules.

44. The process of claim 42, wherein the hydrophobic treatment comprises a gas phase modification or a liquid phase modification.

45. The method of claim 42, wherein the hydrophobic treatment is performed for a period of 3 hours to 10 hours.

46. The method of claim 42, wherein the hydrophobic treatment is performed for a period of 6 hours.

47. A surface-patterned gel, wherein the surface-patterned gel has first and second surface regions of different wettability;

the surface patterned gel is prepared by the preparation method of any one of claims 1 to 46.

48. A surface patterned gel according to claim 47 wherein the first surface region has a contact angle of 65 ° to 120 ° and the second surface region has a contact angle of 5 ° to 45 °.

49. The surface patterned gel of claim 47, wherein the first surface region is enriched in lipophilic groups; the second surface region is enriched with hydrophilic groups.

50. A surface patterned gel according to claim 49 wherein the lipophilic group comprises any or a combination of at least two of alkyl groups, ester groups, ether groups, and aromatic groups.

51. The surface patterned gel of claim 49, wherein the hydrophilic groups comprise any one or a combination of at least two of amide groups, carboxyl groups, hydroxyl groups, and amino groups.

52. A surface patterned gel according to claim 47, wherein the depth of each of the first surface region and the second surface region is independently selected from the group consisting of 4 μm and 20 μm.

53. Use of a surface patterned gel according to any one of claims 47 to 52 for any one or a combination of at least two of pattern transfer, detection of DNA molecules and/or fluorescent molecules, anisotropic adhesion.

54. A pattern transfer stamp comprising a surface patterned gel according to any one of claims 47 to 52, wherein the first surface region and the second surface region of the surface patterned gel are on the same surface.

55. A pattern transfer stamp as in claim 54, wherein in said pattern transfer stamp, said second surface area of said surface patterned gel absorbs water soluble dye and/or said first surface area of said surface patterned gel absorbs oil soluble dye.

56. A method of using the pattern transfer stamp of claim 54 or 55, the method comprising the steps of:

covering the surface of the pattern transfer seal with hydrogel prepolymer, irradiating with ultraviolet light to polymerize the hydrogel prepolymer, and stripping the polymerized hydrogel from the transfer seal after polymerization to realize pattern transfer.

57. The method of using a pattern transfer stamp as claimed in claim 56, wherein said hydrogel pre-polymerization solution includes hydrogel monomers, hydrogel monomer initiators, and hydrogel cross-linking agents dispersed in water.