JP6956403B2 - Porous surface treatment polymer - Google Patents

Description

The present invention relates to a polymer that surface-modifies a polymer porous body by a photoreaction, and a surface modification method.

The polymer porous body is widely used as a base material for manufacturing equipment for separation, purification, reaction control, etc. in fields such as environment, energy, biotechnology, and medical treatment. Various means for producing a porous body have been developed, such as chemical firing, physical firing, or particle agglutination. Then, in order to make the pores of the porous body functional, it is necessary to surface-treat the porous body.
So far, the surface treatment of the base material has adopted the method of introducing functional groups by high-energy treatment such as plasma irradiation, corona discharge, and radiation treatment (Mitsuru Sadamoto, Journal of Vacuum Society Japan, Vol. 51 (No. 1)). Pages 15-18, 2008, Fumio Ide, Journal of the Textile Machinery Society, Vol. 38 (No. 4, pp. 173-185, 1985).
However, it is difficult to apply the surface treatment of the porous body into the pores.

Mitsuru Sadamoto, Journal of Vacuum Society Japan, Vol. 51 (No. 1), pp. 15-18, 2008 Fumio Ide, Journal of the Textile Machinery Society, Vol. 38 (No. 4), pp. 173-185, 1985 Takeo Yamaguchi, Membrane, Vol. 33 (No. 2), pp. 46-53, 2008

An object of the present invention is to provide a surface-treated polymer of a porous body.

As a result of diligent studies to solve the above problems, the present inventor surface-modifies a polymer porous body with the photoreactive polymer by combining a photoreactive polymer and a photoradical generator. We succeeded in developing the process and completed the present invention.

（式中、Ｘ^１及びＸ^２は、それぞれ独立して、重合した状態の重合性原子団を表し、Ｒ^１及びＲ^３は、それぞれ独立して、置換基を有していてもよいフェニル基、−Ｃ（Ｏ）−、−Ｃ（Ｏ）Ｏ−若しくは−Ｏ−で示される基、又は−ＣＯＮＨ−若しくは−ＮＨＣＯＯ−で示される基を表し、Ｒ^２は、水素原子、水酸基、又は次式（ｂ１）：

で示される基を表し、Ｒ^４は、炭素数１〜６のアルキル基を表し、ｍ及びｎは、それぞれ独立して、２〜１０の整数を表し、ａ及びｂは、それぞれ独立して、２以上の整数を表し、Ｘ^１を含む構造単位及びＸ^２を含む構造単位はランダムな順序で結合している。）
で示されるポリマー化合物。
[２] 式（Ｉ）で示される化合物が次式（２）、（３）又は（４）：

（式中、ａ及びｂは、それぞれ独立して、２以上の整数を表し、各モノマーユニットはランダムな順序で結合している。）
で示される構造を有するポリマーである、[１]に記載の化合物。 That is, the present invention is as follows.
[1] The following equation (1):

(In the formula, X ¹ and X ² each independently represent a polymerizable atomic group in a polymerized state, and R ¹ and R ³ each independently represent a phenyl group which may have a substituent. , -C (O)-, -C (O) represents a group represented by O- or -O-, or a group represented by -CONH- or -NHCOO-, where R ² is a hydrogen atom, a hydroxyl group, or the following. Equation (b1):

Represents the group represented by, R ⁴ represents an alkyl group having 1 to 6 carbon atoms, m and n each independently represent an integer of 2 to 10, and a and b independently represent an integer of 2 to 10. It represents an integer of 2 or more, ^{and the structural units containing X 1} and the structural units containing X ² are combined in a random order. )
Polymer compound indicated by.
[2] The compound represented by the formula (I) is the following formula (2), (3) or (4):

(In the equation, a and b each independently represent an integer of 2 or more, and each monomer unit is bonded in a random order.)
The compound according to [1], which is a polymer having the structure shown by.

[3] The compound according to [1] or [2], wherein the value of a / (a + b) is 0.50 to 0.95.
[4] The compound according to any one of [1] to [3], which can hydrophilize the pores of the porous substrate.
[5] A surface treatment agent containing the compound according to any one of [1] to [4].
[6] The treatment agent according to [5], which is in the form of an aqueous solution.
[7] The treatment agent according to [5] or [6], further comprising a photoactivator.
[8] The treatment agent according to [7], wherein the photoactivator comprises a compound having a methyl halide group.
[9] The treatment agent according to any one of [5] to [8], which performs surface treatment using light irradiation treatment.
[10] A porous group comprising a step of applying the treatment agent according to any one of [5] to [9] to a porous substrate and a step of irradiating the applied substrate with light. Material surface treatment method.
[11] A surface-treated porous substrate treated by the method according to [10].
[12] The base material according to [11], wherein the pores of the porous base material are hydrophilized.

The present invention provides a porous surface-treated polymer compound. By using the polymer compound of the present invention, it is possible to perform surface treatment on the pores of the porous body, and simple and efficient surface treatment is possible. Further, since the polymer surface-treated layer is covalently bonded to the base material, the surface-treated porous body has high stability and durability.

¹ H-NMR spectrum of a photoreactive polymer (PMEPMA82). It is an IR spectrum of a photoreactive polymer (PMEPMA82). ¹ H-NMR spectrum of a photoreactive polymer (PHEPMA82) It is an IR spectrum of a photoreactive polymer (PHEPMA82). ¹ H-NMR spectrum of a photoreactive polymer (PBEPMA82). It is an IR spectrum of a photoreactive polymer (PBEPMA82). It is a scanning electron microscope (SEM) image of the surface of PE_AQ800 after surface treatment with PMEPMA. Fluorescent image of PE_AQ800 specimen after staining with Rhodamine 6G. It is a figure which shows the result of having evaluated the water wettability after surface treatment by contact angle measurement. It is a figure which shows a mode that a polymer applied to a porous base material penetrates into a porous pore part and covers the surface of the pore part.

Hereinafter, the present invention will be described in detail. The scope of the present invention is not limited to these explanations, and other than the following examples, the scope of the present invention can be appropriately modified and implemented as long as the gist of the present invention is not impaired.

で示される構造を有する二元系ポリマーである。 1. 1. Polymer compound The present invention has the following formula (1):

It is a binary polymer having the structure shown by.

In formula (1), X ¹ and X ² each independently represent a polymerizable atomic group in a polymerized state. Examples of X ¹ and X ² include vinyl-based monomer residues, acetylene-based monomer residues, ester-based monomer residues, amide-based monomer residues, ether-based monomer residues, urethane-based monomer residues, and the like. Of these, vinyl-based monomer residues are preferable. Further, the ^{structural unit including X 1} and the structural unit including X ² are connected in a random order.

で示される基を表し、好ましくは上記（ｂ１）で示される基である。 R ¹ and R ³ are each independently a phenyl group which may have a substituent, a group represented by -C (O)-, -C (O) O- or -O-, or -CONH. Represents a group represented by − or −NHCOO−, preferably a group represented by −C (O) O−.
R ² is a hydrogen atom, a hydroxyl group, or the following formula (b1):

Represents the group represented by, preferably the group represented by (b1) above.

Specific examples of the substituent of the phenyl group in R ¹ and R ³ include a halogen atom (F, Cl, Br, I), a hydroxyl group, a thiol group, a nitro group, a cyano group, a formyl group, a carboxyl group and an amino group. , Cyril group, methanesulfonyl group, alkyl group having 1 to 6 carbon atoms (C _1-6 alkyl group; other carbon atoms can be expressed in the same manner), C _2-6 alkenyl group, C _2-6 alkynyl group, C. Examples thereof include a _3-8 cycloalkyl group, a C _6-10 aryl group, a C _1-6 alkoxy group, a C _2-7 acyl group or a C _{2-7 alkoxycarbonyl group.}

R ¹ and R ³ may be the same or different. It is preferable that they are the same in terms of polymerization reactivity from the viewpoint of controlling the monomer unit composition of the obtained copolymer.
R ⁴ represents a C _1-6 alkyl group.
m and n each independently represent an integer of 2 to 10, preferably 2.
a and b each independently represent an integer of 2 or more.

In the formula (1), ^{specific examples of the structural unit containing X 1} are not limited, but 2-methacryloyloxyethyl phosphorylcholine, 2-acryloyloxyethylphosphorylcholine, N- (2-methacrylamide) ethylphosphorylcholine, 4-. Methacryloyloxybutylphosphorylcholine, 6-methacryloyloxyhexylphosphorylcholine, 10-methacryloyloxydecylphosphorylcholine, 4-styryloxybutylphosphorylcholine, 2-hydroxyethylmethacrylate, 4-hydroxybutylmethacrylate, 2-aminoethylmethacrylate, 2-dimethylaminoethyl Structural units derived from methacrylate, 2-trimethylammonium ethyl methacrylate, 3-carboxypropyl methacrylate, n-butyl methacrylate, n-hexyl methacrylate and the like are preferably mentioned. Among these, structural units derived from 2-methacryloyloxyethyl phosphorylcholine (MPC) are particularly preferable. As the MPC and other phosphorylcholine compounds (monomer compounds), commercially available products may be used, or they can be easily prepared by a conventional method.
Specific examples of the structural unit containing X ¹ include structural units derived from 2-hydroxyethyl methacrylate, n-butyl methacrylate and the like.

In the formula (1), specific examples of the structural units containing X ^2, but not limited to, for example, derived from a monomer compound represented by the following formula (b2) (N-ethyl--N- phenylamino methacrylate) The structural unit to be used is preferably mentioned.

In the polymer represented by the formula (1), a and b may be integers of 2 or more independently of each other, and here, the value of a / (a + b) is 0.50 to 0.95. , Preferably 0.70 to 0.90. If it is less than 0.50, the inside of the porous material will not be sufficiently hydrophilic. If it is larger than 0.95, the surface coating may not be completed because the photoreaction does not occur effectively. The value of b / (a + b) is 0.50 to 0.05, preferably 0.30 to 0.10.
The weight average molecular weight of the polymer represented by the above formula (1) is not limited, but for example, the range of the molecular weight is 1000 to 500,000, preferably 10000 to 100,000. If it is less than 1000, the surface coating may not be completed due to the poor coating property on the substrate before the photoreaction. If it is larger than 500,000, the viscosity of the polymer solution becomes too high and it is not efficiently introduced into the pores.
The synthesis of the polymer represented by the formula (1) can be carried out by a conventional method basically based on the technical level of those skilled in the art, including the preparation of monomer compounds and the polymerization thereof.

Specific examples of the compound represented by the formula (1) include the compounds of the following formulas (2), (3) or (4).

2. Surface treatment agent As described above, the surface treatment agent for a porous base material of the present invention contains the above-mentioned dual polymer as a main component, and after being applied to the surface of the porous base material, light irradiation treatment is used. Then the surface treatment is performed. As a result, not only the surface portion of the target porous base material (the portion other than the porous pore portion) but also the pore portion can be made hydrophilic.

In addition to the above-mentioned binary polymer, the surface treatment agent of the present invention may contain any other component (for example, various solvents) generally used as a component of the surface treatment agent for the base material. .. Examples of the solvent include a mixed solvent of water and ethanol. In addition, the surface treatment agent of the present invention can include a photoactivator as an auxiliary agent, for example, a compound having a methyl halide group.

Examples of the compound having a polyhalogenated methyl group include, but are not limited to, 2,2,2-tribromoethanol, p-nitro-ω-tribromoacetophenone, hexabromodimethylsulfone and the like. .. These compounds function as photoactivators. For example, radicals generated by photodissociation of these photoactivators by irradiation with light (for example, UV light) acted as initiators and activated the para-position with respect to the amino group of the aromatic ring in the side chain of the polymer. The carbon and the methyl group are substituted, and the radical generated by the dissociation of the halogen (for example, Br) is bonded to the polymer and crosslinked.

The surface treatment agent of the present invention is usually preferably in the form of a solution, and the concentration of the dual polymer contained as a main component is 0.01% to 10% by weight, preferably 0.1. ~ 2% by weight. If it is less than 0.01% by weight, the surface is not completely coated with the polymer. On the other hand, if it exceeds 10% by weight, the invasion of the polymer into the pores is hindered due to the increase in viscosity.
The concentration of the auxiliary agent is 0.005 to 5% by weight.

Examples of the porous base material to be the target base material of the surface treatment agent of the present invention include, and are not limited to, various hydrophobic polymer materials. Examples of the hydrophobic polymer material include acrylic polymers such as polymethyl methacrylate (methacrylic resin; PMMA); various silicone rubbers such as crosslinked polydimethylsiloxane (PDMS) (including substituted silicone and modified silicone); polystyrene, Those made of organic substances such as polyethylene and polycarbonate; examples thereof include a base material whose surface is treated with organic molecules on a metal or ceramic porous body.

The shape of the porous base material is not particularly limited, and examples thereof include a plate shape and a bead shape.
The fields in which porous substrates are used are wide-ranging, especially in the fields of environment, energy, biotechnology, food and medicine or dentistry. The porous substrate obtained by surface treatment using the polymer compound of the present invention can be used as a diaphragm material, an adsorbent, a support, a reaction accelerator, etc. in the processes of production, purification, analysis, etc. in the above fields. Will be done. In the medical field, it is used for, for example, tissue regenerative medicine devices, artificial organs, and the like, and in the dental field, it is used, for example, for dental materials, dental instruments, dental prostheses, and the like.

3. 3. Surface Treatment Method The surface treatment method of the present invention is a method of hydrophilizing not only the surface portion of the porous substrate which is the target substrate but also the pore portion. Specifically, the surface treatment method of the present invention described above. This method includes a step of applying the agent to the porous base material (coating step) and a step of light-irradiating the applied porous base material with light (light irradiation step).
In the coating step, a surface treatment agent containing the binary polymer, which is a photoreactive polymer, as a main component may be used.
In the light irradiation step, the surface treatment agent (liquid) applied to the porous substrate may be dried and then irradiated with light. As the irradiation light, ultraviolet rays (UV light) are preferable because those capable of generating radicals are preferable. The dose of irradiation light is not limited and can be appropriately set based on the ordinary common general knowledge of those skilled in the art.
By the above step, the polymer applied to the porous substrate penetrates into the porous pores and coats the surface of the pores (FIG. 10).

Examples Hereinafter, the present invention will be described in more detail with reference to Examples. However, the scope of the present invention is not limited to these examples.

Synthesis of photoreactive polymer (PMEPMA) (1) Synthesis of photoreactive monomer (EPMA)
2- (N-Ethylanilino) ethanol (8.26 g) and triethylamine (5.57 g) were placed in a three-necked flask, and dichloromethane (80 mL) was added to dissolve them. Chloride methacrylate (5.75 g) was dissolved in dichloromethane (20 mL), placed in a dropping funnel, and slowly added dropwise. After reacting at -2 ° C for 24 hours, the formed triethylamine hydrochloride was removed with a glass filter. Dichloromethane was removed by evaporate and hexane was added to precipitate the dissolved triethylamine hydrochloride. This operation was repeated until triethylamine hydrochloride was no longer precipitated. Furthermore, in order to separate unreacted methacrylic acid chloride and N-ethylanilinoethyl methacrylate (EPMA), extraction was performed with an aqueous hydrochloric acid solution. Anhydrous magnesium sulfate was added to the obtained EPMA hexane solution for dehydration. After filtering anhydrous magnesium sulfate, hexane was removed by evaporator to obtain an oily EPMA.

(2) Synthesis of Photoreactive Polymer (PMEPMA) Next, 2-methacryloyloxyethyl phosphorylcholine (MPC) (2.36 g) and EPMA (0.470 g) were placed in a glass ampoule, and 2,2'-azobis as an initiator. Azobisisobutyronitrile (AIBN) (8.21 mg) was weighed. It was diluted with ethanol to a monomer concentration of 0.5 mol / L and an initiator concentration of 2.5 mmol / L. After sufficiently removing oxygen in the solution with argon, the ampoule was sealed. The reaction was carried out at 60 ° C. for 3 hours using a silicone oil bath. After completion of the reaction, unreacted monomers were removed by a reprecipitation method using a solvent of ether: chloroform = 8: 2. It was dried under reduced pressure to obtain PMEPMA as a white powder.

The MPC unit mole fraction of the obtained PMEPMA was ¹ H-NMR measurement, and the value of a / (a + b) was 0.82. The yield was 1.76 g and the yield was 62%. Further, the gel permeation chromatography (GPC) results Its molecular weight was determined by measuring the number average molecular weight (Mn) of 5.8 x 10 ^4, weight average molecular weight (Mw) of 1.7 x 10 ^5, a polydispersity of 2.9. FIG. 1 is a ¹ H-NMR spectrum of the obtained PMEPMA82. FIG. 2 shows the obtained IR spectrum of PMEPMA82.

The copolymerization reaction was carried out in the same manner as in Example 1 except that the molar ratio of MPC and EPMA was changed to 90/10. The yield was 1.77 g and the yield was 61%. As a result of molecular weight was determined by GPC measurement, Mn is 5.2 x 10 ^4, Mw is 1.4 x 10 ^5, a polydispersity of 2.7.

The copolymerization reaction was carried out in the same manner as in Example 1 except that the molar ratio of MPC and EPMA was changed to 70/30. The yield was 1.53 g and the yield was 55%. As a result of molecular weight was determined by GPC measurement, Mn is 6.1 x 10 ^4, Mw is 1.9 x 10 ^5, a polydispersity of 3.1.

A copolymerization reaction with EPMA was carried out using 2-hydroxyethyl methacrylate (HEMA) instead of the MPC of Example 1 to obtain PHEPMA.
2-Hydroxyethyl methacrylate (HEMA) (0.520 g) and EPMA (0.230 g) were weighed into a glass ampoule, and 2,2'-azobisisobutyronitrile (AIBN) (4.11 mg) was weighed as an initiator. It was diluted with ethanol to a monomer concentration of 0.5 mol / L and an initiator concentration of 2.5 mmol / L. After sufficiently removing oxygen in the solution with argon, the ampoule was sealed. The reaction was carried out at 60 ° C. for 8 hours using a silicone oil bath. After completion of the reaction, unreacted monomers were removed by a reprecipitation method using a solvent of ether: chloroform = 8: 2. It was dried under reduced pressure to obtain PHEPMA as a white powder. The HEMA unit mole fraction of the obtained PHEPMA was ¹ H-NMR measurement, and the value of a / (a + b) was 0.83. FIG. 3 is a ¹ H-NMR spectrum of the obtained PHEPMA82. FIG. 4 shows the obtained IR spectrum of PHEPMA82.

A copolymerization reaction with EPMA was carried out using n-butyl methacrylate (BMA) instead of the MPC of Example 1 to obtain PBEPMA.
N-Butyl methacrylate (BMA) (0.570 g) and EPMA (0.230 g) were weighed into a glass ampoule, and 2,2'-azobisisobutyronitrile (AIBN) (4.11 mg) was weighed as an initiator. Diluted with tetrahydrofuran to a monomer concentration of 0.5 mol / L and an initiator concentration of 2.5 mmol / L. After sufficiently removing oxygen in the solution with argon, the ampoule was sealed. The reaction was carried out at 60 ° C. for 8 hours using a silicone oil bath. After completion of the reaction, unreacted monomers were removed by a reprecipitation method using a methanol solvent. It was dried under reduced pressure to obtain PBEPMA as a white powder. The BMA unit mole fraction of the obtained PBEPMA was ¹ H-NMR measurement, and the value of a / (a + b) was 0.81. FIG. 5 is a ¹ H-NMR spectrum of the obtained PBEPMA82. FIG. 6 is an IR spectrum of the obtained PBEPMA 82.

Photoreaction to a porous body As a base material, a porous polyethylene specimen with a pore size of 61 μm ( ^{Cyfine TM} AQ grade manufactured by Asahi Kasei Corporation: PE_AQ800) was used. PMEPMA82 (0.20 g) and 2,2,2-tribromoethanol (100 mg) were weighed and dissolved by adding ethanol so that the PMEPMA concentration was 0.50 wt%. PE_AQ800 was immersed in the obtained solution for 1 minute. After air drying, PMEPMA was reacted by irradiating with UV light (254 nm) (light intensity) for 3 minutes. After UV irradiation, unreacted PMEPMA was removed by immersing in ethanol with stirring overnight.

A photoreaction was carried out on the porous body in the same manner as in Example 6 except that PMEPMA91 was used as the photoreactive polymer.

A photoreaction was carried out on the porous body in the same manner as in Example 6 except that PMEPMA73 was used as the photoreactive polymer.

Surface observation with scanning electron microscope (SEM)
The surface of PE_AQ800 after surface treatment with PMEPMA was observed with a scanning electron microscope (SEM). As shown in FIG. 7, there was no significant change in the pore size even after the surface treatment. Since PMEPMA forms a thin film layer only on the surface of PE_AQ800, it does not affect the properties as a porous material.

Evaluation of surface reaction by dyeing
The PE_AQ800 specimen surface-treated with PMEPMA was immersed in a 2 ppm Rhodamine 6G aqueous solution for 30 seconds. Then, it was rinsed 50 times in water in 50 mL and observed with a fluorescence microscope. Rhodamine 6G is a cationic, lipophilic fluorescent dye that selectively stains phospholipid polar groups. The observation image by the fluorescence microscope is shown in FIG. Fluorescence was observed up to the inside of the pores, and it was confirmed that PMEMA also crosslinked inside the pores by UV irradiation. Figure 8 is a fluorescence image of the PE_AQ800 specimen after staining with Rhodamine 6G.

Evaluation of surface wettability by contact angle measurement The water wettability after surface treatment was evaluated by contact angle measurement (Fig. 9). As a control sample, cyclic polyolefin (CPO) having a smooth surface was used.
The contact angle of the CPO surface was about 100 degrees, while the contact angle of PMEPMA73, PMEPMA82, and PMEPMA9 after surface treatment was about 50-65 degrees, which was hydrophilic. It is considered that PMEPMA was photocrosslinked on the surface of the CPO substrate and the surface was covered with a phosphorylcholine group to make it hydrophilic. On the other hand, since the surface of PE_AQ800 has a porous structure, it showed a high contact angle of about 120 degrees. PMEPMA showed a low value of about 45-80 degrees after surface treatment, indicating that surface treatment is possible even for porous materials.

Claims (12)

Equation (1):

(In the formula, X ¹ and X ² are independently vinyl-based monomer residues, acetylene-based monomer residues, ester-based monomer residues, amide-based monomer residues, ether-based monomer residues, or urethane-based monomer residues. Representing a group , R ¹ and R ³ are independently phenyl groups which may have substituents, and are groups represented by -C (O)-, -C (O) O- or -O-. , Or a group represented by -CONH- or -NHCOO-, where R ² is a hydrogen atom , or the following formula (b1):

Represents the group represented by, R ⁴ represents an alkyl group having 1 to 6 carbon atoms, m and n each independently represent an integer of 2 to 10, and a and b independently represent an integer of 2 to 10. It represents an integer of 2 or more, ^{and the structural units containing X 1} and the structural units containing X ² are combined in a random order. However, R ³ excludes the group represented by -C (O) O-, and R ^{4 excludes the methyl group.} )
Polymer compound indicated by. The compound represented by the formula (I) is the following formula (2) or (4) :

(In the equation, a and b each independently represent an integer of 2 or more, and each monomer unit is bonded in a random order.)
The compound according to claim 1, which is a polymer having the structure shown by. The compound according to claim 1 or 2, wherein the value of a / (a + b) is 0.50 to 0.95. The compound according to any one of claims 1 to 3, which can make the pores of the porous substrate hydrophilic. A surface treatment agent containing the compound according to any one of claims 1 to 4. The treatment agent according to claim 5, which is in the form of an aqueous solution. The treatment agent according to claim 5 or 6, further comprising a photoactivator. The treatment agent according to claim 7, wherein the photoactivator comprises a compound having a methyl halide group. The treatment agent according to any one of claims 5 to 8, wherein the surface treatment is performed by using a light irradiation treatment. A method for surface treating a porous substrate, which comprises a step of applying the treatment agent according to any one of claims 5 to 9 to the porous substrate and a step of irradiating the applied substrate with light. .. A surface-treated porous base material treated by the method according to claim 10. The base material according to claim 11, wherein the pores of the porous base material are made hydrophilic.

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