KR101912461B1 - Polymer brush with easy control of length and rigidity - Google Patents

Abstract

The present invention relates to a polymer brush formed on a base material. More specifically, the present invention relates to a polymeric brush which ensures easy adjustment of length via partial photo-oxidation and unit lamination as well as easy adjustment of stiffness, and can be useful as a surface coating material in various fields. The present invention further relates to a production method thereof.

Description

TECHNICAL FIELD [0001] The present invention relates to a polymer brush which can be easily controlled in length and stiffness,

The present invention relates to a polymer brush formed on a substrate. More particularly, the present invention relates to a polymer brush useful as a surface coating material in various fields, and a method of manufacturing the polymer brush, which can be easily controlled in length and rigidity through partial photo-oxidation and unit lamination.

A polymer brush is a collection of polymer chains in which one end of the chain is chemically or physically bonded to the surface or interface. This is determined by the density at the surface or by the molecular weight. In addition, the other of the polymer chain terminals can be functionalized with various functional groups. Such polymer brushes are being applied to various biological phenomena occurring on biomolecules and on the surface of a given specific material, and their application range including surface modification such as terminal functionalization is expanding.

However, the precise adjustment of the length of the polymer brush at the nanometer level to implement various characteristics still has difficult technical difficulties, so that the research and application of polymer brushes having a nanometer-length is severely limited.

Methods for forming polymer brushes include grafting-from or grafting-to methods.

The grafting-to is carried out by reacting already synthesized polymer chains with the desired substrate. In order to control the polymer length, it is necessary to control the length in the synthesis step of the polymer. In this case, the repulsive force acts due to the steric hindrance between the polymer chains, thereby lowering the packing density of the polymer. The surface-initiated polymerization method (grafting-from) is a method in which a polymer chain synthesized through polymerization is reacted on a surface of a substrate to be treated with an initiator using an initiator, and the polymer chain is precisely controlled If you can not get the length of the desired polymer brush.

Therefore, it is necessary to research and develop a polymer brush that can minimize the degradation of properties such as low density caused by steric hindrance of polymer and precisely control the thickness of polymer brush by simple process.

Korean Registered Patent No. 10-1200796 (2012.11.07)

It is an object of the present invention to provide a polymer brush in which the thickness can be adjusted while maintaining physical properties of the polymer to be laminated and the vertical stiffness in the thickness direction is precisely controlled.

It is another object of the present invention to provide a polymer brush which can be applied to various fields such as biosensors, tissue engineering, electronic materials, and devices, including fields requiring delicate surface coating.

Another object of the present invention is to provide a method of manufacturing a polymer brush capable of precisely controlling the thickness of the polymer brush by a simple process and easily controlling rigidity and ductility of the formed polymer brush.

In order to achieve the above object, the present invention provides a substrate comprising: a substrate; And a polymer brush comprising at least two polymer monolayer formed on the substrate.

In one embodiment of the present invention, the polymer brushes are formed by partial photo-oxidation, and the polymer brushes may be formed by any one or more of combinations selected from intra-chain reaction, inter-chain reaction, And the like.

In one embodiment of the present invention, the polymer has a number average molecular weight of 1,000 to 500,000 g / mol.

The present invention also provides a surface coating material comprising the polymer brush.

In addition, the present invention provides a method for manufacturing a semiconductor device, comprising: a surface modification step of aminating the surface of a plasma-treated substrate; a monolayer formation step of forming a first polymer layer on the surface-modified substrate; And forming a second polymer layer after the amination treatment on the monolayer, and then photo-oxidizing the second polymer layer. The present invention also provides a method for producing a polymer brush.

In an embodiment of the present invention, the double layer forming step is repeated at least once.

In one embodiment of the present invention, the polymer brushes are formed by partial photo-oxidation, and the polymer brushes may be formed by any one or more of combinations selected from intra-chain reaction, inter-chain reaction, And the like.

The polymer brush according to the present invention has an advantage that the physical properties of the polymer to be laminated are not deteriorated and at the same time the vertical rigidity in the thickness direction is excellent and furthermore the density is increased toward the upper thickness direction on the basis of the substrate, .

In addition, the polymer brush according to the present invention has an advantage that it can be applied to various fields such as biosensors, tissue engineering, electronic materials, electronic devices, and display devices, including fields requiring delicate surface coating.

In addition, the method of manufacturing a polymer brush according to the present invention can precisely control the thickness of a polymer brush at a nanometer or micrometer level by a simple process, and can easily control physical properties such as rigidity and ductility of the formed polymer brush And has the advantage of being able to fill defects or defects that may occur during the polymer brush lamination.

1 schematically shows a polymer brush composed of a single layer.
2 schematically shows a polymer brush according to an embodiment of the present invention.
3 schematically illustrates a polymer brush according to an embodiment of the present invention.
FIG. 4 is a comparative measurement of the contact angle of each layer of the polymer brush and the glass substrate with respect to water according to an embodiment of the present invention.
FIG. 5 is an optical microscope photograph showing changes in behavior of animal cells as the PDMS polymer brush layer is increased.
FIG. 6 is an optical microscope photograph showing the behavioral changes of animal cells (SF295 cell line) of bulk PDMS and PDMS nano-brush over time.
FIG. 7 shows the difference in the degree of proliferation exhibited by the glass for cell culture, nanometer-thick PDMS nano-brush, and bulk PDMS-cells on each substrate over time as shown through the cell population analysis (MTS assay) Fig.
8 shows optical images (Fig. 8) showing adhesion, shape formation and proliferation of cells cultured in PDMS brush (4L-PDMS nanobrush) and bulk PDMS (PDMS brush) laminated with a single layer PDMS brush and four layers according to Example 2 Cells used: hMSC, NIH3T3, CAD).

Hereinafter, the polymer brush of the present invention and a method for producing the same will be described in detail. The present invention may be better understood by the following examples, which are for the purpose of illustration only and are not intended to limit the scope of protection defined by the appended claims. The technical terms and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs, unless otherwise defined.

In the present invention, 'partial photooxidation' means that photo-oxidation degree is controlled. As a concrete example, the degree of photo-oxidation of a target component is controlled through ultraviolet ray irradiation. When the whole brush is viewed, many parts indicate the extent to which only the polymer brush tip is modified with a hydroxy group while maintaining the physical properties of the original polymer itself do.

The term 'polymer layer' in the present invention means a layer formed by stacking layers of nanometer or micrometer-scale polymers on the substrate or other polymer layer by grafting-to. As an example, FIG. 1 shows a monolayer PDMS brush formed on top of a modified substrate, wherein the single layer is viewed as an aspect of the polymer layer. The single layer may have an unfolded shape (left), a folded shape (right), and the like at the same time.

The inventors of the present invention have found that it is easy to control length and stiffness by producing a polymer brush having a multi-layered structure through a photooxidation reaction as a result of a study on a polymer brush having a length of nanometer or micrometer level Thereby completing the present invention.

The polymer brush according to the present invention overcomes the disadvantages of the grafting-from or grafting-to method to overcome the low density arising from the steric hindrance of the chain length polymer, and the thickness of the polymer brush Can be precisely controlled, and the rigidity of each layer can be precisely controlled on a multi-layer structure, which is advantageous in application to a field requiring delicate surface coating.

The polymer brush according to the present invention comprises a substrate and two or more polymer monolayer on the substrate.

The base material in the present invention is not limited as long as it can easily form a polymer brush irrespective of kinds and forms. For example, the substrate may be any one selected from glass, silicon, ceramic, plastic, metal, and metal oxide, but is not limited thereto.

In the present invention, the polymer brush comprises two or more polymer monolayers on the substrate. Conventionally, a polymer brush made of a single polymer layer has difficulty in controlling its length due to difficulty in controlling its molecular weight. Even when the length of the polymer is controlled, the polymer is folded by itself in a soft material, There has been a problem that can not be achieved. Alternatively, the polymer brush according to the present invention may include a single layer of two or more polymers through an intra-chain reaction, an inter-chain reaction, or the like, Not only can it remain stable, but also its rigidity and ductility can be controlled.

Particularly, the polymer brush of the present invention forms a multi-layer structure by layer-by-layer of a polymer single layer, that is, unit lamination method, unlike simply increasing the length to increase the thickness. This not only allows easy control of stiffness and ductility, but also has thickness control and continuous thickness retention characteristics. At this time, the lamination of the polymer monolayer is performed by photo-oxidation, specifically, oxidation reaction to the polymer chain by ultraviolet irradiation. Further, the polymer brush of the present invention can control the physical properties by controlling the photo-oxidation degree. Controlling the degree of photo-oxidation refers to partial photo-oxidation, wherein the laminated polymer monolayer is subjected to intra-chain reactions, inter-chain reactions and adjacent A reaction between the polymer monolayers and a reaction between the polymer monolayers, and forms a multi-layer structure including at least two polymer monolayers. The two or more polymer monolayer may be a multilayer such as a bilayer, a triple layer, or the like in which adjoining polymer monolayers are grafted and bonded.

The polymer brush according to the present invention not only increases the density from the substrate to the upper layer due to the oxidation reaction in the chain or the interchain oxidation reaction in addition to the bonding force due to the grafting between the polymer monolayers, Defects and defects can be drastically reduced, and the effect of preventing pinholes is excellent.

The thickness of the polymer monolayer according to the present invention is not particularly limited, but may be 1 to 1,000 nm, preferably 2 to 100 nm, more preferably 3 to 10 nm. When the above range is satisfied, it is effective in controlling rigidity and ductility of the polymer brush.

The polymer of the present invention can be used without limitation as long as it is suitable for the coating property of the surface. The polymer may be at least one selected from the group consisting of polysiloxane, polystyrene, polymethyl methacrylate, and polyethylene oxide, but is not limited thereto.

As specific examples, the polymer may be a siloxane-based polymer, specifically polydimethylsiloxane, polydiethylsiloxane, polydimethylsiloxane-co- (C ₁ -C ₅ ) alkylmethylsiloxane, polydimethylsiloxane-co-diphenylsiloxane, poly But are not limited to, dimethylsiloxane-co-methylphenylsiloxane, and polydimethylsiloxane-co-methyl (3,3,3-trifluoro) propylsiloxane.

The molecular weight of the polymer is not particularly limited, but may be adjusted according to the desired length in consideration of length control and physical properties. Preferably, the number average molecular weight is 1,000 to 500,000 g / mol, more preferably 2,000 to 100,000 g / mol, and even more preferably 3,000 to 50,000 g / mol in terms of controlling the length on the nanometer or micrometer level effective.

The polymer may be one having a terminal functionalized or capable of functionalization through modification. Preferably, the chain terminal is hydroxylated or has a glycidyl group at the terminal. In the case of a polymer having a glycidyl group, it can form an excellent bonding force when bound to a substrate or when bound to a single polymer layer.

The polymer monolayer is formed by bonding a polymer on a substrate and then performing partial photo-oxidation by ultraviolet light.

The polymer formed on the substrate is photo-oxidized to introduce a hydroxyl group, and the introduced hydroxyl group can perform an intra-chain reaction and an inter-chain reaction within a single polymer layer, It may also react with a single layer of polymer.

In addition, the density, rigidity, etc. of the polymer single layer can be controlled by adjusting the degree of partial photooxidation.

The polymer brush according to an embodiment of the present invention has a contact angle to water of 90 to 110 °, preferably 100 to 105 °. This can significantly reduce the wettability and is effective in lowering the surface energy.

Another aspect of the present invention relates to a surface coating material comprising the polymer brush.

The surface coating material imparts functionalities to the surface. For example, a polymer brush manufactured using a siloxane-based resin is a surface coating material capable of maintaining smooth and precise thicknesses on the nanometer or micrometer level, Can be provided. It can be applied to a surface coating material such as an electronic material, a display material, a biosensor and the like, which imparts functionalities to the surface.

Further, another aspect of the present invention relates to a cell culture container comprising the polymer brush.

The cell culture container is capable of culturing animal cells or cells of microorganisms. Compared with a glass substrate, the cell culture container can clearly show changes in cell behavior such as cell adhesion, cell morphogenesis, and cell proliferation. This can replace the glass substrate and has the advantage of increasing cost and time by increasing cell culture productivity.

Another aspect of the present invention is a method for producing a plasma-treated substrate, comprising a surface modification step of aminating the surface of the plasma-

A single-layer forming step of forming a first polymer layer on the surface-modified substrate,

A photo-oxidation step of photo-oxidizing the single layer; and

Forming a second polymer layer after the amination treatment on the photo-oxidized single layer and then photo-oxidizing the second polymer layer,

And a method for producing the polymer brush.

The surface modification step is a pretreatment step for grafting the polymer onto the surface of the substrate. As the surface modification method, a usual method can be used. Preferably, amination is performed for treating the substrate surface with an amine. (3-aminopropyl) trimethoxysilane, [3- (2-aminoethylamino) propyl] trimethoxysilane, and [3- Aminomethylamino) propyl] triethoxysilane, and the present invention is not limited thereto. In addition, surface amination can be smoothly carried out by modifying the surface before the amination step. For example, oxygen plasma treatment or the like may be performed, but the present invention is not limited thereto.

A photo-oxidation step of photo-oxidizing the first polymer layer is performed after the single-layer formation step. At this time, the photo-oxidation can be carried out without limitation as far as the polymer of the first polymer layer can be functionalized in an oxide form by light irradiation on the first polymer layer. Preferably, ultraviolet irradiation is used, and the irradiation amount and the irradiation time can be adjusted according to the photo-oxidation degree.

When the partial photo-oxidation of the first polymer layer is performed through the photo-oxidation step, a step of amine-treating the end of the first polymer layer is performed in the same manner as the modification of the surface of the base material. This is a pretreatment process for forming the second polymer layer. Next, the second polymer layer is formed on the amine-treated first polymer layer, and then the photo-oxidation treatment is performed.

Such a double layer forming step may be repeated at least once in the same time as the polymer brush manufacturing step, and multiple layers such as various double layers and triple layers are formed through repeated processes. The multi-layer includes an intra-chain oxidation reaction in the polymer monolayer, an inter-chain oxidation reaction, and a reaction between the polymer monolayers. The double layer forming step includes a step of forming a polymer layer and an oxidation reaction due to photooxidation through a repeated process to thereby form a double layer brush and simultaneously prevent defects and pinholes that may occur in the single layer polymer brush, And a high density can be achieved by making the portion cross-linked through an oxidation reaction in the chain or an oxidation reaction between chains.

Hereinafter, a polymer brush having a multilayer structure according to the present invention and a method for producing the same will be described. However, the present invention is not limited to the following examples.

(Example 1)

The glass substrate was subjected to oxygen plasma treatment to form a hydroxyl group (-OH) on the substrate. The plasma-treated substrate was subjected to self-monolayer assembly (SAM) using (3-aminopropyl) triethoxysilane (APTES, (3-aminopropyl) triethoxysilane) to make the terminal group -NH ₂ . Polydimethylsiloxane (PDMS, number average molecular weight: 5,000 g / mol) having a terminal monoglycidyl ether was applied to the substrate and then heat-treated at 80 DEG C for 4 hours. The heat - treated substrate was washed with isopropyl alcohol (IPA) and dried at room temperature to produce a single - layer polymer brush.

The substrate on which the single-layer polymer brush was formed was irradiated with ultraviolet rays. Photo-oxidation was induced by irradiation of ultraviolet rays, and amidation was carried out using APTES used before the photo-oxidized polymer monolayer so that the terminal was NH ₂ , and polydimethylsiloxane (PDMS, A number average molecular weight of 5,000 g / mol) was applied to the substrate, and then the substrate was thermally treated at 80 DEG C for 4 hours and photo-oxidation was carried out once to obtain a PDMS brush having a two-layer structure.

(Example 2)

A PDMS brush having a three-layer structure was produced in the same manner as in Example 1, except that the double layer formation process was repeated twice in Example 1. [

(Example 3)

A PDMS brush having a four-layer structure was prepared in the same manner as in Example 1, except that the double layer formation process was repeated three times in Example 1. [

(Comparative Example 1)

Except that PDMS having a number average molecular weight of 10,000 g / mol was used instead of the polydimethylsiloxane used in Example 1 and a step of photo-acidifying by ultraviolet irradiation was not performed, A polymer brush was prepared.

FIG. 2 is a schematic view of a polymer brush according to Example 1, showing the oxidation reaction in the chain and the interchain oxidation due to photooxidation. Such an intracellular oxidation reaction and an interchain oxidation reaction are more preferable because they can achieve high densification in the thickness direction from the substrate as well as mechanical properties such as rigidity of the polymer brush.

Fig. 3 shows a high-density polymer brush (double layer) according to the first embodiment.

4 is a comparative measurement of the contact angle of each layer of the PDMS brush and the glass substrate according to Examples 1 to 3 of the present invention. The polymer brush according to the embodiment exhibited an excellent contact angle with a contact angle to water of 100 to 103 °, which was similar to that of the single layer bulk PDMS brush (100 °) according to Comparative Example 1, which is not shown in the drawing. This shows that the PDMS brushes of the embodiments according to the present invention are well formed on the substrate with a very thin thickness as compared with the bulk PDMS brush.

FIG. 5 is an optical microscope photograph showing the behavioral change of the animal cell (SF295) according to the increase of the PDMS polymer brush layer. In the bulk PDMS brush according to Comparative Example 1, cell adhesion and morphogenesis were severely deviated from the normal category , And cell proliferation was also inhibited. On the other hand, the PDMS brush according to the embodiment of the present invention showed cell and tissue-friendly characteristics such that the PDMS brush hardly differed from the cell behavior in the glass substrate for cell culture. However, as the lamination of the PDMS polymer brush increases, the attachment of animal cells, cell morphogenesis, and cell proliferation are changed into cell behavior by the bulk PDMS brush according to Comparative Example 1. [ This means that the single-layer PDMS polymer brush is cell and tissue-friendly, but as the PDMS polymer brush layer is piled up, the degree of cell and tissue non-affinity increases. By using these characteristics, the single layer polymer brush requires cell and tissue affinity It can be applied to tissue engineering.

6 to 8 are graphs showing animal cell behaviors using PDMS brushes according to Example 1 and Comparative Example 1 of the present invention. They show various types of cancer cells (HeLa, SF295 cell line), fibroblasts (NIH3T3) Cells (human Mesenchymal Stem Cell) were cultured and observed. The PDMS brush according to Example 1 of the present invention is cell and tissue-friendly. However, as the number of layers increases, the cell and tissue non-affinity . Using these characteristics, the multi-layered polymer brush can be applied to areas where tissue non-affinity is required. For example, it can be applied to instruments requiring an antifouling effect, such as a stent. In addition, it is possible to expand the application including the general surface coating method, and it has an advantage that the productivity can be increased.

Claims (7)

A surface modification step of aminating the surface of the plasma-treated substrate;
A single-layer forming step of forming a first polymer layer on the surface-modified substrate;
A photo-oxidation step of photo-oxidizing the single layer;
Aminizing the surface of the photooxidized monolayer;
A bilayer forming step of forming a second polymer layer on the aminated single layer; And
And a photo-oxidation step of photo-oxidizing the double layer, the polymer brush comprising:
materials;
A single layer of a first polymer formed on the substrate; And
And a second polymer layer formed on the single layer,
Wherein the first polymer and the second polymer are at least one selected from the group consisting of polysiloxane, polystyrene, polymethyl methacrylate, and polyethylene oxide,
The thickness of the single layer and the double layer is 1 to 1,000 nm,
The single layer and the double layer include a combination of an intra-chain reaction and an inter-chain reaction by photo-oxidation,
The interface between the single layer and the double layer is grafted and bonded by photo-
The hydroxyl groups introduced into the first polymer and the second polymer by the photo-oxidation function in the chain reaction and the chain reaction, react with the adjacent single-layer polymer,
By controlling the degree of photo-oxidation, the density and stiffness of the single layer and the double layer can be controlled,
The polymer brush is capable of controlling the thickness while controlling the physical properties of the polymer to be laminated, adjusting the rigidity in the thickness direction, and increasing the density by filling defects or flaws that may occur when the polymer brushes are laminated Polymer brush.
delete delete A surface coating material comprising the polymer brush of claim 1.
A surface modification step of aminating the surface of the plasma-treated substrate;
A single-layer forming step of forming a first polymer layer on the surface-modified substrate;
A photo-oxidation step of photo-oxidizing the single layer;
Aminizing the surface of the photooxidized monolayer;
A bilayer forming step of forming a second polymer layer on the aminated single layer; And
And a photo-oxidation step of photo-oxidizing the double layer, the method comprising the steps of:
Wherein the first polymer and the second polymer are at least one selected from the group consisting of polysiloxane, polystyrene, polymethyl methacrylate, and polyethylene oxide,
The thickness of the single layer and the double layer is 1 to 1,000 nm,
The single layer and the double layer include a combination of an intra-chain reaction and an inter-chain reaction by photo-oxidation,
The interface between the single layer and the double layer is grafted and bonded by photo-
The hydroxyl groups introduced into the first polymer and the second polymer by the photo-oxidation function in the chain reaction and the chain reaction, react with the adjacent single-layer polymer,
By controlling the degree of photo-oxidation, the density and stiffness of the single layer and the double layer can be controlled,
The polymer brush is capable of controlling the thickness while controlling the physical properties of the polymer to be laminated, adjusting the rigidity in the thickness direction, and increasing the density by filling defects or flaws that may occur when the polymer brushes are laminated (Method for manufacturing a polymer brush).
6. The method of claim 5,
Wherein the step of forming the double layer is repeated at least once or more.
delete

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