CN117970746A - Composition for preparing patterned film, patterned substrate and preparation method of patterned substrate - Google Patents

Abstract

The invention belongs to the technical field of polymer materials, and particularly relates to a composition for preparing a patterning film, a patterning substrate and a preparation method thereof. The composition of the invention comprises the following components in parts by weight: 1-4 parts of photopolymer monomer, 1-4 parts of cross-linking agent, 0.05-0.1 part of photoinitiator, 2-8 parts of plasticizer and 0.1-1 part of auxiliary agent. The composition is subjected to photo-curing on a substrate material by digital light, and a substrate with a patterned film on the surface can be manufactured. The preparation method is simple and high in precision, and the prepared patterned substrate can realize accurate control of surface functionalization according to different material selection and modification modes, so that the requirements of different application scenes are met. In a word, the invention provides a tool box for efficiently manufacturing the multifunctional microchip, and has good application prospect in preparation of functional micropatterns.

Description

Composition for preparing patterned film, patterned substrate and preparation method of patterned substrate

Technical Field

The invention belongs to the technical field of polymer materials, and particularly relates to a composition for preparing a patterning film, a patterning substrate and a preparation method thereof.

Background

In nature, surface patterns from nano-to micro-scale can impart certain special skills to living beings, such as controllable adhesion and release, self-cleaning, ability to refract reflected light or capture moisture from mist, etc., and engineering challenges can be solved by mimicking natural strategies. For example, imitate ecological and in vivo microenvironments, or produce superhydrophobic surfaces, adhesives, and structural colors. Various properties of polymers, such as adhesion, wettability or biocompatibility, depend on the material surface, and therefore surface modification in terms of morphology (surface patterning) or chemistry is an indispensable step in using polymeric materials. Patterning polymers into microstructures and developing new functionalized surfaces are critical in the fields of optics, biology, sensors, microfluidics, etc.

Prior studies have explored various micropatterning methods, and the most widely used patterning techniques today still rely on conventional lithography (hard lithography), including photolithography, electron beam lithography, dip pen nanolithography, focused ion beam lithography, EVU lithography, and the like. However, the above-mentioned photolithography method still has the problems of high requirement on the cleanliness of the environment, consideration of the suitability between the photoresist and the substrate, complex and difficult process, high requirement on equipment, and the like. In order to break through the limitations of traditional lithography, many non-conventional lithographic techniques have been developed, such as microcontact printing, nanoimprinting, respiratory patterning, etc., but these processes can only print on certain types of substrates, limiting the diversity of their properties.

Digital Light Processing (DLP) is a technology for projection display using a Digital Micromirror Device (DMD). At the heart of digital light processing technology is a Digital Micromirror Device (DMD), which consists of a number of tiny mirror plates, each of which can be controlled in its direction of reflection by a digital signal. This enables DLP technology to achieve high resolution image display. The digital light processing technology can be used in the light curing molding technology, and the light hardening resin is used as a material, and the digital light source is used for carrying out layer-by-layer projection on the surface of the liquid photosensitive resin in a surface light mode, so that the light hardening resin can be cured and molded layer by layer. The technology has the characteristics of ultrahigh precision, smooth surface and good quality. Thus, digital light processing techniques combined with photo-curing molding of polymers are expected to provide a new method of preparing patterned surfaces.

Not only does the design and fabrication of a material with the desired properties and versatility require patterning of its surface, but subsequent surface functionalization is also important. How to design the composition of the photo-curable polymer so that the resulting patterned surface has a controlled pattern and function remains an important research topic in the art.

Disclosure of Invention

The invention provides a composition for preparing a patterned film, a patterned substrate and a preparation method thereof.

A composition for patterned film preparation comprising the following components in parts by weight:

1-4 parts of photopolymer monomer,

1-4 Parts of cross-linking agent,

0.05 To 0.1 part of photoinitiator,

2-8 Parts of plasticizer,

0.1-1 Part of auxiliary agent;

Wherein the photopolymer monomer is selected from (meth) acrylic monomers that are photocrosslinked, the crosslinker is selected from (meth) acrylate di-or polyfunctional monomers that are photocrosslinkable, and the photoinitiator is selected from ultraviolet-visible light band-initiated initiators.

Preferably, the photopolymer monomer is at least one selected from the group consisting of hydroxyethyl methacrylate and hydroxyethyl acrylate;

and/or the cross-linking agent is selected from ethylene glycol dimethacrylate and ethylene glycol diacrylate.

Preferably, the auxiliary agent is selected from the group consisting of the light absorber sudan 1;

And/or the plasticizer is at least one selected from cyclohexanol, decanol and toluene;

and/or the photoinitiator is selected from at least one of phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide or 1-hydroxycyclohexyl phenyl ketone.

Preferably, the composition comprises the following components in parts by weight:

3 parts of photopolymer monomer,

2 Parts of cross-linking agent,

0.1 Part of phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide,

2 Parts of cyclohexanol,

3 Parts of decyl alcohol,

Sudan 1.3 parts.

The invention also provides a patterned substrate which is obtained by photo-curing the composition on a substrate material through digital light.

Preferably, in the photocuring process, the composition forms a liquid film with a thickness of 6-50 μm on the surface of the base material, and then is photocured by digital light;

And/or the wavelength of the photo-curing is 365-405nm.

Preferably, the base material is a substrate with the surface modified by 3-methacryloxypropyl trimethoxysilane; the substrate is selected from glass, metal or organic PET.

Preferably, the patterned substrate surface comprises a patterned film formed from the composition and a bare substrate material; the surface of the patterned film is further modified by adopting a modifying molecule through hydroxyl or active double bonds, and/or the surface of the substrate material is further modified by adopting a modifying molecule through active double bonds.

The invention also provides a preparation method of the patterned substrate, which is to carry out photo-curing on the composition on a substrate material through digital light.

The invention also provides the use of the patterned substrate described above as a functionalized surface in the fields of cell culture, rapid screening kits, single cell screening or automated synthesis.

The present invention provides a composition for patterned film preparation, with which, in combination with 3D printing techniques, a micropatterned film (i.e., a patterned film) of a functionalized (e.g., having super-hydrophilic/super-hydrophobic properties) porous polymer can be custom-formed on a desired substrate as desired, using a digital light processing light source, to form a region-functionalized surface of the substrate alternating with the polymer film.

The beneficial effects of the invention include:

1. The invention can prepare the functionalized surface in one step through photocuring, and the preparation method is simple and easy to popularize and apply;

2. The substrate material suitable for the invention has various types and good applicability.

3. The pattern may be controlled according to digital light processing techniques; in addition, the surface of the polymer film and the surface of the substrate material have active reaction sites, and the polymer film and the substrate material are allowed to be further modified by different monomers through a 3D printing technology again, so that new surface properties are obtained. Therefore, the invention has good control on the pattern and the functionalization of the surface.

4. According to the invention, through free combination of multiple materials, two different surface features can be selectively combined together according to application requirements, so that requirements of occasions such as cell culture and screening, liquid encapsulation, micro-droplet reaction and the like can be met.

In a word, the invention provides a tool box for efficiently manufacturing the multifunctional microchip, and has good application prospect in preparation of functional micropatterns.

It should be apparent that, in light of the foregoing, various modifications, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

The above-described aspects of the present invention will be described in further detail below with reference to specific embodiments in the form of examples. It should not be understood that the scope of the above subject matter of the present invention is limited to the following examples only. All techniques implemented based on the above description of the invention are within the scope of the invention.

Drawings

FIG. 1 is a schematic diagram of chip printing of the DMD-based maskless lithography system used in example 1;

FIG. 2 is a photograph of a porous polymer printed at various exposure times and corresponding micro-topography, cross-sectional topography, and water contact angle for example 1;

FIG. 3 is an optical photograph of a porous polymer film printed on a glass substrate and a flexible PET substrate, respectively, in example 1;

FIG. 4 is a physical image of the patterned polymer film printed by the DLP 3D printer in example 1 and a display of printing accuracy;

FIG. 5 is an EDX analysis of polymer films before and after modification of hydrophobic monomers and mechanical properties of the modified superhydrophobic polymer films in example 2;

FIG. 6 is a graph showing the results of the test for the water contact angle of the modified glass substrate in example 2;

fig. 7 is an experimental result of optimizing the formulation based on the accuracy of the cured pattern in experimental example 1.

Detailed Description

In the following examples and experimental examples, reagents and raw materials not specifically described are commercially available.

Example 1 composition for patterned film preparation and patterned substrate made therefrom

The composition (prepolymer solution) provided in this example consisted of:

3g HEMA (hydroxyethyl methacrylate), 2g EDMA (ethylene glycol dimethacrylate), 100mg phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide (819 photoinitiator), 2g cyclohexanol, 3g decanol, 300mg Sudan 1.

The method for preparing the patterned substrate by using the prepolymer solution comprises the following steps:

A base material (glass substrate, metal sheet or flexible PET) was selected and pre-modified with 3-methacryloxypropyl trimethoxysilane. The specific process is as follows: the substrate material is soaked in 1M NaOH for 1h, soaked in 1M HCl for 30min, taken out, washed with water and ethanol, and dried. And (3) dripping 10-100 mu L of 3-methacryloxypropyl trimethoxy silane ethanol solution between the two substrates, standing for 12h, separating the two substrates, washing with ethanol, and drying for later use.

Preparation as shown in FIG. 1, 45. Mu.L of the prepolymer solution was dropped onto a printing plate before printing, and the liquid film thickness was 6. Mu.m. At this time, after the substrate is positioned on the printing platform. Subsequently, the pre-designed print pattern is introduced into a DMD based lithography system and projected onto the print stage in the form of 365nm, 385nm or 405nm blue light (preferably 405nm in this embodiment). After the exposure was completed, the substrate was separated, and thoroughly washed with ethanol and then air-gun dried.

Photographs of the porous polymer and corresponding micro-topography, cross-sectional topography, and water contact angles were printed on glass substrates at different exposure times according to the method of this example as shown in fig. 2. From the figure, the microscopic morphology of the porous polymer and the water contact angle of the porous polymer film change along with the change of the 3D printing exposure time, which shows that the method of the embodiment can simply and rapidly adjust the microscopic morphology of the porous polymer so as to be suitable for different application scenes. In addition, the thickness of the porous polymer film formed by final photolithography was controlled using a polyimide film of 6 μm in the method of the present example, which is consistent with the thickness of the cross section of the film characterized by SEM in fig. 2, so that in the method, the thickness of the porous polymer film obtained by final photolithography can be precisely controlled using polyimide films of different thicknesses.

This example an example of a patterned substrate prepared on a glass substrate and flexible PET with a pre-designed pattern is shown in fig. 3. A physical image of the patterned polymer film printed by the DLP 3D printer and a display of printing accuracy are shown in fig. 4, and experimental results indicate that a minimum of 80 μm feature structure can be obtained by the DLP.

Example 2 patterned substrate obtained after modification

1. Modification of porous polymer membranes by small molecule chemical reactions:

The porous polymer membrane has active hydroxyl groups on its surface and can thus be modified by different chemical methods.

Specifically, the patterned substrate prepared in example 1 was placed in a 50ml sealed tube. 25ml of methylene chloride was added to immerse the sample, 50mg of 4-dimethylaminopyridine, 80. Mu.L of ethylenediamine and 60. Mu.L of pentadecafluorooctanoyl chloride (PFOC) were added in this order, and they were stirred at room temperature under an inert atmosphere for 4 hours. The sample was then removed, washed thoroughly with ethanol and dried with an air gun.

2. Modification of the porous polymer by photopolymerization grafting method:

The porous polymer film surface has residual active double bonds and thus can be modified by different polymerization methods.

Specifically, 532mg of perfluorohexyl ethyl methacrylate, 10mg of 819 initiator and 20mg of 4-methoxyphenol were dissolved in 200. Mu.l of ethyl acetate to prepare a polymerization reaction solution. After that, 20 to 80. Mu.l of the reaction solution was dropped onto the printing platform. The patterned substrate prepared in example 1 was placed on top, aligned with the exposure pattern. After exposure for 20 seconds, the sample was lifted, thoroughly washed with ethanol and dried with an air gun. And repeating the process, and obtaining the modified patterned substrate after accumulating the total exposure time to be 200 seconds.

Successful performance of the surface modification was demonstrated by performing a series of performance tests on the polymer films prepared by the two processes described above. In order to prove that the super-hydrophobic porous polymer film prepared by the process has excellent mechanical properties, namely the film still has super-hydrophobic properties after being worn for many times, the mechanical property test is carried out on the super-hydrophobic porous polymer film prepared on a glass substrate. Specifically, the modified patterned substrate prepared by the process is placed on a platform of an injection pump, one surface (namely the surface of a porous polymer film) to be tested is tightly attached to sand paper, weights with different qualities are bonded with a sample together to regulate and control the pressure applied to the surface of the polymer film, the speed of the sample and the moving speed of the weights on the sample relative to the surface of the sand paper are controlled by regulating and controlling the pumping speed of the injection pump, the sample and the moving speed of the weights on the sample relative to the surface of the sand paper are moved for 9cm each time, and the sample is repeated for 20 times. The results after the test are shown in fig. 5, and the water contact angle of the surface of the super-hydrophobic porous polymer film modified under different pressures is less in change compared with the water contact angle before friction, so that the film has good mechanical properties.

3. Modifying the glass substrate:

the surface of the glass substrate has residual active double bonds, so that the areas which are not covered by the polymer can be chemically modified by using methods such as mercapto-alkene click chemistry or photo grafting.

Specifically, four reaction solutions were first prepared: (1) 16mg of 819 initiator and 500 mu L of 1h, 2 h-perfluorodecanethiol are dissolved in 5mL of DMF and mixed uniformly to prepare a reaction solution 1; (2) 500. Mu.L of 2- (perfluorooctyl) ethyl methacrylate and 15mg of an initiator were dissolved in 5mL of DMF and mixed uniformly to prepare a reaction solution 2; (3) 500 mu L of methacryloyl ethyl trimethyl ammonium chloride and 11mg 819 of initiator are dissolved in 5mL of DMF and uniformly mixed to prepare a reaction solution 3; (4) mu.L of 1-thioglycerol and 11mg 819 of an initiator were dissolved in 5mL of ethanol, and the mixture was reacted to prepare a reaction solution 4.

In example 1, the entire surface of the glass substrate was modified in advance, specifically, after taking 20. Mu.L to 25X 30X 1mm of any one of the above four reaction solutions on the modified glass substrate, the device was covered with quartz glass and exposed to light using an LED light source (405 nm, 45W, 1.2mW cm ^-2) for 90 seconds.

The glass substrate may also be area modified, specifically using the same DLP lithography system as the light source (405 nm, 15W), creating a custom exposure pattern on the computer, and dropping 20. Mu.L of the reaction solution onto the print platform. The modified 25X 30X 1mm glass substrate was placed on a printing stage and the exposure was continued for 200 seconds.

The surface of the glass substrate (modified with different hydrophilic/hydrophobic monomers) prepared by the above process was subjected to a water contact angle test, and as a result, as shown in fig. 6, the water contact angles of the glass surface modified with different monomers were all different from that of the original glass substrate, which confirmed that the glass substrate was successfully modified by the above process.

The technical scheme of the invention is further described through experiments.

Experimental example 1 formulation optimization of composition for patterned film preparation

1. Experimental method

A patterned substrate was prepared as in example 1, except that the formulation of the composition (prepolymer solution) was adjusted.

The formulation was first optimized based on curing effect, each experimental set of formulations as follows:

the formulation was then optimized based on the accuracy of the cured pattern, the formulation for each experimental set was as follows:

2. Experimental results

The results of the optimization of the formulation based on the curing effect are shown in the following table:

The reasonable proportion of the components of the monomer and the porogen in the prepolymer solution is critical to the macroscopic property, the microscopic morphology, the good mechanical property and the like of the formed porous polymer film. As can be seen from the above table results, the key point of forming the porous morphology is that the ratio of the two pore-forming agents (cyclohexanol and decanol) is that the content of cyclohexanol is relatively high, so that the formed polymer film is too compact, when the decanol content is zero, a compact and smooth transparent polymer film is formed, and the enough roughness of the film surface cannot be ensured, so that a good hydrophobic surface cannot be formed in the subsequent modification; conversely, if the decanol level is too high relative to cyclohexanol, the mechanical properties of the resulting porous polymer film are too poor to maintain macroscopic morphology. From the results of the above table, the optimum ratio of cyclohexanol to decanol was 2:3.

In addition, in order to be suitable for various application scenes, the polymerization process of the prepolymer should ensure the highest possible photoetching precision in a general environment. In general, the polymerization inhibition and proximity effect of oxygen in the printing process will greatly reduce the accuracy of photolithography, and the addition of a certain amount of sudan 1, a polymerization inhibitor, can effectively eliminate the diffusion of free radicals, reduce the adverse effect of dissolved oxygen on the accuracy in the polymerization process, but too much polymerization inhibitor will significantly increase unnecessary printing time while reducing the mechanical properties of the formed patterned porous polymer film. The results of the screening experiments on the amount of Sudan 1 are shown in FIG. 7, and the optimal amount of Sudan 1 is 3% of the total mass.

As can be seen from the examples above, the compositions and methods provided in accordance with the present invention are capable of producing a substrate having a patterned film on the surface. The preparation method is simple and high in precision, and the prepared patterned substrate can realize accurate control of surface functionalization according to different material selection and modification modes, so that the requirements of different application scenes are met. Therefore, the invention has good application prospect.

Claims (10)

1. A composition for patterned film preparation, comprising the following components in parts by weight:

1-4 parts of photopolymer monomer,

1-4 Parts of cross-linking agent,

0.05 To 0.1 part of photoinitiator,

2-8 Parts of plasticizer,

0.1-1 Part of auxiliary agent;

Wherein the photopolymer monomer is selected from (meth) acrylic monomers that are photocrosslinked, the crosslinker is selected from (meth) acrylate di-or polyfunctional monomers that are photocrosslinkable, and the photoinitiator is selected from ultraviolet-visible light band-initiated initiators.

2. A composition according to claim 1, wherein: the photopolymer monomer is at least one selected from hydroxyethyl methacrylate and hydroxyethyl acrylate;

and/or the cross-linking agent is selected from ethylene glycol dimethacrylate and ethylene glycol diacrylate.

3. A composition according to claim 1, wherein: the auxiliary agent is selected from light absorber Sudan 1;

And/or the plasticizer is at least one selected from cyclohexanol, decanol and toluene;

And/or the photoinitiator is selected from at least one of phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide or 1-hydroxycyclohexyl phenyl ketone.

4. The composition according to claim 1, comprising the following components in parts by weight:

3 parts of photopolymer monomer,

2 Parts of cross-linking agent,

0.1 Part of phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide,

2 Parts of cyclohexanol,

3 Parts of decyl alcohol,

Sudan 1.3 parts.

5. A patterned substrate, characterized in that it is obtained by photocuring a composition according to any one of claims 1 to 4 on a substrate material by means of digital light.

6. The patterned substrate according to claim 5, wherein: in the photocuring process, the composition forms a liquid film with the thickness of 6-50 mu m on the surface of a substrate material, and then photocuring is carried out through digital light;

And/or the wavelength of the photo-curing is 365-405 nm.

7. The patterned substrate according to claim 5, wherein: the substrate material is a substrate material with the surface modified by 3-methacryloxypropyl trimethoxy silane; the substrate is selected from glass, metal or organic PET.

8. The patterned substrate of claim 7, wherein: the patterned substrate surface comprises a patterned film formed by the composition and a bare substrate material; the surface of the patterned film is further modified by adopting a modifying molecule through hydroxyl or active double bonds, and/or the surface of the substrate material is further modified by adopting a modifying molecule through active double bonds.

9. The method of preparing a patterned substrate according to any one of claims 5 to 8, wherein the composition is obtained by photocuring the composition on a substrate material by digital light.

10. Use of the patterned substrate of any one of claims 5-8 as a functionalized surface in the field of cell culture, rapid screening kits, single cell screening or automated synthesis.