TWI812781B - Manufacturing method of surface modified substrate - Google Patents

Abstract

The polymer manufacturing method provided by the present invention uses easily available materials, and the polymerization conditions do not need to be strictly controlled. High molecular weight (meth)acrylic polymers that are conventionally difficult can also be obtained under relatively mild conditions. . The manufacturing method of the polymer of the present invention includes: under a pressure condition of 100 to 1,000 MPa, a temperature condition above 60°C, and starting with a starting group represented by the general formula (1) or (2). A step of polymerizing (meth)acrylic acid-based monomers in the coexistence of original compounds and salts such as halogenated quaternary ammonium salts to form a (meth)acrylic-based polymer with a number average molecular weight of 100,000 to 10,000,000.

(X係表示氯原子等；Y係表示O或NH；R₁~R₄係表示烷基等；「*」係表示鍵結位置)

(X represents a chlorine atom, etc.; Y represents O or NH; R ₁ ~ R ₄ represents an alkyl group, etc.; "*" represents a bonding position)

Description

Manufacturing method of surface modified substrate

The present invention relates to a method for producing a high molecular weight polymer ((meth)acrylic polymer) and a method for producing a surface modification base material.

In recent years, there has been research on the so-called "Concentrated Polymer Brush" that uses the living radical polymerization technology developed in the 1990s to graft high-density onto the substrate. The thick polymer brush is composed of polymer chains grafted onto the substrate at a high density with intervals of 1 to 4 nm. By using this thick polymer brush to modify the surface of the substrate, you can impart features such as low friction, protein adsorption inhibition, molecular sieve properties, hydrophilicity, water repellency, etc. (e.g. Patent Documents 1 and 2, Non-Patent Documents 1 to 3) .

[Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Laid-Open No. 2008-133434

[Patent Document 2] Japanese Patent Application Publication No. 2010-261001

[Non-patent literature]

[Non-patent document 1] Adv. Polym. Sci., 2006, 197, 1-45

[Non-patent document 2] J. Am. Chem. Soc., 2005, 127, 15843-15847

[Non-patent document 3]Polym. Chem., 2012, 3, 148-153

Conventional thick polymer brushes are almost always produced by atom transfer radical polymerization. The atom transfer radical polymerization method is a type of living radical polymerization method. It introduces initiating groups such as halogen onto the substrate, and then utilizes a redox reaction using a metal complex such as copper or ruthenium as a catalyst. However, the atom transfer radical polymerization method is time-consuming to remove heavy metals such as copper used. In addition, due to the use of heavy metals, there are also concerns about the burden on the environment. In addition, the atom transfer radical polymerization method requires purification of monomers or materials, and strict management of polymerization conditions such as oxygen concentration, etc., making it a somewhat complicated method.

The present invention was completed in view of the problems of this conventional technology, and its object is to provide a method that can obtain a high molecular weight that is conventionally difficult by using easily available materials, and the polymerization conditions do not need to be strictly controlled, and can be obtained under relatively mild conditions. A method for producing a (meth)acrylic polymer. Furthermore, an object of the present invention is to provide a polymer that can be formed from a high molecular weight (meth)acrylic polymer that is conventionally difficult using easily available materials and without strict control of polymerization conditions under relatively mild conditions. Method for manufacturing a surface-modified substrate with a sufficiently thick polymer layer.

That is, according to the present invention, a method for producing the polymer shown below can be provided.

[1] A method for manufacturing a polymer, which includes: applying a pressure of 100 to 1,000 MPa The (meth)acrylic acid-based monomer is polymerized under strong conditions, a temperature of 60°C or above, and the coexistence of the starting compound and a salt to form a polystyrene equivalent measured by a gel permeation chromatography analyzer. A step of producing a (meth)acrylic polymer with a number average molecular weight of 100,000 to 10,000,000; wherein, the above starting compound has a starting group represented by the following general formula (1) or (2); and, the above salt is derived from At least one selected from the group consisting of quaternary ammonium halide salts, quaternary phosphonium halide salts, and alkali metal halide salts.

(In the above-mentioned general formula ( ₁ ), ; R ₂ represents an alkyl group, aryl group, cyano group, acyl group, carboxyl group, ester group, or amide group; "*" represents a bonding position)

(In the above-mentioned general _formula (2) _, Alkyl, aryl, or acyl group; "*" indicates the bonding position)

[2] The method for producing a polymer according to the above [1], wherein the polymer is produced from an alcohol-based solvent, a glycol-based solvent, an amide-based solvent, an ether-based solvent, a trine-based solvent, a urea-based solvent, and an ion-based solvent. In at least one organic solvent selected from the group consisting of liquids, the above-mentioned (meth)acrylic monomer is polymerized under temperature conditions below the boiling point of the above-mentioned organic solvent. combine.

[3] The method for producing a polymer according to the above [1] or [2], wherein the salt is a group consisting of a quaternary ammonium iodide salt, a quaternary phosphonium iodide salt, and an alkali metal iodide salt. Choose at least one from the group.

[4] The method for producing a polymer according to any one of the above [1] to [3], wherein the obtained (meth)acrylic polymer has a molecular weight distribution (weight average molecular weight/number average molecular weight) It is below 1.8.

Furthermore, according to the present invention, a method for manufacturing a surface-modified substrate shown below can be provided.

[5] A method for manufacturing a surface-modified substrate, which includes: using a treatment agent having a starting group represented by the following general formula (1) or (2) and an alkoxysilane group to perform surface treatment on the substrate. The step of treating to obtain a treated base material; and causing the (meth)acrylic monomer to process Polymerize to form a (meth)acrylic polymer with a number average molecular weight of 100,000 to 10,000,000 in terms of polystyrene as measured by a gel permeation chromatography analyzer, and on the surface of the above-mentioned treated substrate, a layer containing the above (meth)acrylic polymer is disposed. base) acrylic polymer and a polymer layer with a thickness of 100 nm or more.

(In the above-mentioned general formula ( ₁ ), ; R ₂ represents an alkyl group, aryl group, cyano group, acyl group, carboxyl group, ester group, or amide group; "*" represents a bonding position)

(In the above-mentioned general _formula (2) _, Alkyl, aryl, or acyl group; "*" indicates the bonding position) (compare the efficacy of the previous technology)

According to the present invention, it is possible to provide a polymer that can obtain a high molecular weight (meth)acrylic polymer, which is conventionally difficult, using easily available materials, and the polymerization conditions do not need to be strictly controlled, and can be produced under relatively mild conditions. method. Furthermore, according to the present invention, it is possible to provide that high molecular weight (meth)acrylic polymers, which are conventionally difficult, can be formed using easily available materials, and the polymerization conditions do not need to be strictly controlled, and can be formed under relatively mild conditions. Method for manufacturing a surface-modified substrate with a sufficiently thick polymer layer. That is, by utilizing the production method of the polymer of the present invention, it is possible to produce base materials such as parts or members whose surfaces are provided with various properties.

<Production method of polymer>

Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments. The manufacturing method of the polymer of the present invention includes: under pressure conditions of 100~1,000MPa, under temperature conditions above 60°C, and starting In the coexistence of the compound and the salt, the (meth)acrylic monomer is polymerized to form a (meth)acrylic polymer with a polystyrene-converted number average molecular weight of 100,000 to 10,000,000 as measured by a gel permeation chromatography analyzer. material step (polymerization step).

(polymerization step)

The polymerization step is carried out under pressure conditions of 100~1,000MPa, preferably 200~800MPa, and more preferably 300~600MPa. Specifically, polymerization is performed while uniformly applying pressure to the entire polymerization container in which the (meth)acrylic acid-based monomer has been placed via a medium such as water. By performing radical polymerization under pressure and suppressing reaction cessation, a (meth)acrylic polymer with a higher molecular weight can be formed. If the pressure is less than 100MPa, the target high molecular weight polymer cannot be obtained. On the other hand, it is difficult and impractical to prepare containers or devices that can withstand pressures exceeding 1,000MPa.

The polymerization container is preferably a container that can be sealed and can withstand high pressure. In addition, pressure must be transmitted to the inside of the container, so it is preferable to use a container that has a plastic soft part or a stretchable part that can deform due to pressure. Specifically, various containers such as polyethylene bottles, plastic bottles, sterilization bags, and bubble containers can be used. Furthermore, it is preferable that the container is made of a heat-resistant material that is not easily deformed by the temperature during polymerization. Furthermore, it is preferable that the container is made of a material that is difficult to penetrate, such as polymerization solvents, and has properties such as chemical resistance or solvent resistance. Examples of materials constituting the polymerization container include polyolefin-based resins, fluorine-based resins, polyester-based resins, polyamide-based resins, and engineering plastics. In addition, during polymerization, it is preferable to conduct the polymerization in such a manner that gas does not enter the polymerization container. For example, it is preferable that the polymerization solution is filled to 90% or more of the capacity of the polymerization container.

In the polymerization step, polymerization is performed at a temperature of 60°C or higher, preferably 70°C or higher. In addition, polymerization is preferably performed at a temperature of 200°C or lower, more preferably 120°C or lower.

During the polymerization step, the halogen in the specific starting group will be released in the form of a free radical, and polymerization will proceed from the place where it was released (carbon radical). Therefore, in order to react with the salt when the radicals of the halogen are detached, it is necessary to set the predetermined temperature conditions.

(starting compound)

The starting compound is a compound having a starting group represented by the following general formula (1) or (2). The polymerization proceeds from the starting group of the starting compound. Specifically, X in the general formula (1) or (2) is detached in the form of a radical, and at the same time, a carbon radical is generated and inserted into the monomer for polymerization. Thereby, a polymer terminated with the starting group is formed.

(In the above-mentioned general formula ( ₁ ), ; R ₂ represents an alkyl group, aryl group, cyano group, acyl group, carboxyl group, ester group, or amide group; "*" represents a bonding position)

In the general formula (1), the carbon atom to which X is bonded is a tertiary carbon atom or a quaternary carbon atom. Preferably, at least one of R ₁ and R ₂ is a group other than an alkyl group. That is, if at least one of R ₁ and R ₂ is an electron-donating group other than an alkyl group, X will be released more easily. In particular, if X is bonded to a quaternary carbon atom, it will generate free radicals, so it is more preferable.

(In the above-mentioned general _formula (2) _, Alkyl, aryl, or acyl group; "*" indicates the bonding position)

In the general formula (2), the carbon atom to which X is bonded is a tertiary carbon atom or a quaternary carbon atom. Since the ester group or amide group is an electron-donating group, R ₃ and R ₄ may both be alkyl groups. In addition, if X is bonded to a quaternary carbon atom, free radicals will be generated, so it is more preferable.

As the starting compound, a commercially available compound or a synthetic compound may be used. The starting compound can be obtained, for example, by reacting iodine with an azo radical polymerization initiator such as azobisisobutyronitrile or dimethyl azoisobutyrate.

(salt)

The salt is at least one selected from the group consisting of quaternary ammonium halide salts, quaternary phosphonium halide salts, and alkali metal halide salts. The X (halogen) in the starting group will be released in the form of a free radical, and at the same time, the monomer will be inserted into the carbon radical generated with the release of X and polymerization will proceed. At this time, by allowing a specific salt to coexist, halogen radicals are detached or halogen exchange occurs, and monomers are polymerized from the generated carbon radicals to form a polymer.

等。鹵化四級鏻鹽係可舉例如：氯化四苯鏻、溴化甲基三丁鏻、碘化四丁鏻等。鹵化鹼金屬鹽係可舉例如：溴化鋰、碘化鉀等。 Examples of halogenated quaternary ammonium salts include benzyltrimethylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetraoctyl ammonium iodide, nonylpyridinium chloride, and bile chloride.

wait. Examples of halogenated quaternary phosphonium salts include tetraphenylphosphonium chloride, methyltributylphosphonium bromide, and tetrabutylphosphonium iodide. Examples of alkali metal halide salts include lithium bromide, potassium iodide, and the like.

As the salt, iodide salt is preferably used. By using iodide salts, living radical polymerization occurs, and polymers with a narrower molecular weight distribution can be obtained. Moreover, it is preferable to use a salt which can be dissolved in a polymerization solution, such as a quaternary ammonium iodide salt, a quaternary phosphonium iodide salt, and an alkali metal iodide salt, and it is more preferable to use a quaternary ammonium iodide salt. Examples of quaternary ammonium iodide salts include: benzyl tetrabutylammonium iodide, tetrabutylammonium iodide, tetraoctyl ammonium iodide, dodecyltrimethylammonium iodide, stearyltrimethylammonium iodide, iodine Tri(octadecyl)methane, etc.

From the viewpoint of improving the activity and obtaining a thicker and high molecular weight polymer, the amount of the salt relative to the starting group is preferably equal to or more moles, more preferably 10 times or more moles, and may also be set to More than 100 times mole.

((meth)acrylic monomer)

As the (meth)acrylic monomer system, conventionally known (meth)acrylic monomers can be used. In this specification, "(meth)acrylic monomer" includes (meth)acrylic acid in addition to (meth)acrylate.

酯、(甲基)丙烯酸金剛烷酯等(甲基)丙烯酸烷基酯系、(甲基)丙烯酸環烷基酯系單體； Examples of the (meth)acrylic monosystem include: (meth)acrylic acid; methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-(meth)acrylate Butyl ester, tert-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, dodecane (meth)acrylate ester, (meth)octadecyl acrylate, (meth)cyclohexyl acrylate, (meth)trimethylcyclohexyl acrylate, (meth)acrylic acid cyclodecyl ester, (meth)acrylic acid trimethylester Cyclodecyl ester, iso(meth)acrylate

Ester, adamantane (meth)acrylate and other (meth)alkyl acrylate series, (meth)acrylic acid cycloalkyl ester series monomers;

2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate and other (meth)hydroxyalkyl acrylate monomers;

Methoxyethoxyethyl (meth)acrylate, polyethylene glycol (meth)acrylate, polyethylene glycol monomethyl ether (meth)acrylate, polypropylene glycol monomethyl ether (meth)acrylate , Glycidyl (meth)acrylate, 3-ethyloxetanyl (meth)acrylate, 2,2-dimethyl-1,3-dioxolane-4-methanol ( (meth)acrylate oxyalkyl ester monomers such as meth)acrylate and glucosoxyethyl (meth)acrylate;

等(甲基)丙烯酸胺基烷酯系、(甲基)丙烯酸銨基烷酯系單體； -N,N'-dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, tert-butylaminoethyl (meth)acrylate, (meth)acrylic acid chloride Benzyldimethylammonium ethyl ester, (meth)acrylic acid trimethylethyl chloride, (meth)acrylic acid dimethylammonium ethyl bistrifluoromethane salt, 2-(meth)acryloxyethyl bile phosphate

(Meth)acrylic acid aminoalkyl ester and (meth)acrylic acid ammonium alkyl ester monomers;

(Meth)acrylic acid-2,2,2-trifluoroethyl, (meth)acrylic acid-2-perfluorobutylethyl, (meth)acrylic acid-2-perfluorooctylethyl, etc. contain fluorine atoms The (meth)acrylate monomer; the terminal (meth)acrylate of polydimethylsiloxane and other silicon polymers are monomers Monomers; (meth)acrylic acid ethyl phosphate, (meth)acryloxypropyltrimethoxysilane, (meth)acryloxyethyl isocyanate and other highly reactive monomers, etc.

The method for producing the polymer of the present invention uses a (meth)acrylic monomer having a carboxyl group or a highly reactive group, and can be used directly without protecting the carboxyl group or the highly reactive group. The conventional atom transfer radical polymerization method uses a metal complex of polyamine as a catalyst. However, if an acid component such as a monomer having a carboxyl group is allowed to coexist, the metal complex that is the catalyst is destroyed and the polymerization reaction does not proceed. On the other hand, in the method of producing the polymer of the present invention, the polymerization reaction is carried out in a state where functional groups such as carboxyl groups and phosphate groups are not protected.

By setting the starting group and the amount ratio of the (meth)acrylic monomer, the molecular weight of the obtained polymer can be controlled to a certain extent. For example, if 5,000 moles of a monomer with a molecular weight of 100 are used for polymerization relative to 1 mole of the starting compound, a polymer with a theoretical molecular weight of "1×100×5,000=500,000" will be formed. That is, the molecular weight of the obtained monomer can be calculated from the formula [1 mol of starting compound × molecular weight of monomer × molar ratio of starting compound to monomer].

(organic solvent)

In the polymerization step, the (meth)acrylic monomer is preferably polymerized in an organic solvent. In particular, by conducting polymerization in an organic solvent that can dissolve the polymer formed, the polymer can be prevented from solidifying and can be easily disposed of. In addition, from the viewpoint of industrial and productivity safety, it is preferable to polymerize the (meth)acrylic monomer under temperature conditions below the boiling point of the organic solvent.

As the organic solvent, conventionally known solvents for polymerization can be used. In particular, it is preferable to use at least one organic solvent selected from the group consisting of alcohol-based solvents, glycol-based solvents, amide-based solvents, ether-based solvents, trine-based solvents, urea-based solvents, and ionic liquids. Because these organic solvents are highly polar, they can dissolve the aforementioned salts. In addition, by using such organic solvents with high polarity, the speed of halogen exchange can be further accelerated, so it is preferable.

Examples of alcohol-based solvents include isopropyl alcohol, butanol, hexanol, and the like. Examples of glycol solvents include ethylene glycol, propylene glycol, poly(n=2 or more) ethylene glycol monomethyl ether, poly(n=2 or more) ethylene glycol monobutyl ether, poly(n=2 or more) Propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, etc. Examples of amide solvents include dimethylformamide, dimethylacetamide, 2-pyrrolidone, N-methylpyrrolidone, and 3-methoxy-N,N-dimethyl Propamide, 3-butoxy-N,N-dimethylpropamide, etc.

Examples of ether solvents include diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and the like. Examples of the teresine-based solvent system include cyclotenine, dimethyl teresine, and the like. Examples of urea solvents include tetramethylurea, dimethylimidazolinone, and the like. Examples of ionic liquid systems include: ethyl(3-methoxypropyl)dimethylammonium bis(trifluoromethanesulfonyl)imide, 1-butyl-3-methylimidazolium tetrafluoroborate, N,N-diethyl-N-methyl-N-2-methoxyethylammonium bis(trifluoromethanesulfonyl)imide, etc. Among these organic solvents, it is preferable to use non-volatile organic solvents because they are less likely to expand during polymerization, and it is preferable to use organic solvents with a boiling point of 150° C. or above.

((meth)acrylic polymer)

(Meth)acrylic polymer produced by the production method of the polymer of the present invention The number average molecular weight (Mn) converted to polystyrene measured by gel permeation chromatography (GPC) is 100,000 to 10,000,000, preferably 300,000 to 8,000,000, and more preferably 500,000 to 5,000,000. That is, according to the manufacturing method of the polymer of this invention, a high molecular weight (meth)acrylic polymer which is difficult to manufacture normally, such as solution polymerization, can be easily manufactured. This is considered to be because polymerization under high-pressure conditions suppresses reaction cessation and promotes the growth reaction. In addition, (meth)acrylic polymers with Mn less than 100,000 can be produced by other polymerization methods (solution polymerization, block polymerization, emulsion polymerization, etc.). On the other hand, it is essentially difficult to produce a (meth)acrylic polymer having an Mn exceeding 10,000,000.

Furthermore, the molecular weight distribution (weight average molecular weight (Mw)/number average molecular weight (Mn) = PDI) of the (meth)acrylic polymer produced by the method for producing the polymer of the present invention is preferably 1.8 or less, more preferably Department 1.4 or less.

Since the (meth)acrylic polymer produced by the method of producing the polymer of the present invention has a high molecular weight, it can be effectively used as a coating agent for forming a coating layer with excellent durability, and various Molding raw material for molded objects.

<Manufacturing method of surface modification substrate>

The manufacturing method of the surface modified substrate of the present invention includes: surface treatment of the substrate using a treatment agent having a starting group represented by the following general formula (1) or (2) and an alkoxysilane group The steps to obtain the treated substrate (pre-treatment step); and under pressure conditions of 100~1,000MPa, temperature conditions above 60°C, and treatment of the substrate In the coexistence of materials and salts, (meth)acrylic monomers are polymerized to form a (meth)acrylic polymer with a number average molecular weight of 100,000 to 10,000,000 in terms of polystyrene as measured by a gel permeation chromatography analyzer. A step (polymerization step) of arranging a polymer layer containing a (meth)acrylic polymer and having a thickness of 100 nm or more on the surface of the treated substrate. That is, the manufacturing method of the surface-modified substrate of the present invention utilizes the aforementioned manufacturing method of the polymer to modify the surface of the substrate to form a polymer layer of a predetermined thickness on the surface of the substrate to obtain the surface-modified substrate. Methods.

(In the above-mentioned general formula ( ₁ ), ; R ₂ represents an alkyl group, aryl group, cyano group, acyl group, carboxyl group, ester group, or amide group; "*" represents a bonding position)

(In the above-mentioned general _formula (2) _, Alkyl, aryl, or acyl group; "*" indicates the bonding position)

(Substrate)

Examples of the substrate system include: silicon substrate; glass substrate; metal, ceramic, alumina, silicon carbide, boron nitride, ITO film, plastic plate, plastic film and other plate-shaped and film-shaped substrates; Fibrous substrates such as glass fiber and carbon fiber, etc. In addition, filler-like base materials such as pigments, silica, and magnetic powder can also be used.

(treatment agent)

In the pretreatment step, the base material is surface treated using a treatment agent having a starting group represented by general formula (1) or (2) and an alkoxysilane group. Thereby, a treated substrate in which a predetermined starting group is bonded to the surface of the substrate can be obtained. Examples of alkoxysilyl groups include methoxydimethylsilyl, ethoxydimethylsilyl, dimethoxysilyl, diethoxysilyl, trimethoxysilyl, and triethoxy Silyl group, chloromethoxysilyl group, etc. Specific examples of treatment agents having a predetermined starting group and alkoxysilane group include compounds represented by the following formulas (3) to (7):

Furthermore, it may also be composed of a monomer represented by the following formula (8) and (meth)acryloxypropyltrimethylsilane or (meth)acryloxypropyltriethoxysilane. A polymer (polymer-type treatment agent) obtained by polymerizing a monomer component of an alkoxysilyl monomer is used as a treatment agent. In addition, the polymer used as the treatment agent may be a polymer having a structure such as polyester, polyurethane, or polyamide, or may be a polymer having a random structure, a block structure, a graft structure, a star structure, or a star structure. Polymers with structures such as particles.

Before surface treatment with a treatment agent, the base material can also be pre-treated. Examples of the pretreatment system include: silane coupling treatment, silica treatment, alumina treatment, silica alumina treatment, zirconium dioxide treatment, UV irradiation, plasma irradiation, electron beam irradiation, radiation irradiation, ozone oxidation, etc. Cleaning, activation, and addition of functional groups.

The treatment agent is a compound having an alkoxysilane group. Therefore, the surface treatment of the substrate can be performed using a treatment agent using a conventionally known silane coupling treatment method such as a dry treatment method or a wet treatment method. The dry treatment method is a method in which the treatment agent is sprayed directly or dissolved in a low-boiling solvent or the like, and applied to the surface of the substrate, and then dried. The wet treatment method is a method in which the base material is immersed in a solution of a treatment agent and then dried. In addition, in the case of the aforementioned polymer-type treatment agent, a thicker layer can also be formed using techniques such as dip coating, coater, spin coating, etc., and then the base material can be planarized.

(polymerization step)

In the polymerization step, the (meth)acrylic monomer is polymerized in the same manner as in the polymerization step of the above-mentioned polymer production method. That is, the (meth)acrylic monomer is polymerized under pressure conditions of 100 to 1,000 MPa, temperature conditions of 60° C. or higher, and the coexistence of the treatment base material and salt. Thereby, a (meth)acrylic polymer is formed, and A surface-modified substrate having a polymer layer disposed on the surface of the treated substrate can be obtained.

The pressure conditions and temperature conditions during polymerization, including preferred conditions, are the same as the pressure conditions and temperature conditions of the aforementioned polymer production method. In addition, the monomers used and the salts coexisting during polymerization are the same as those used in the above-described method of producing the polymer, including preferred ones.

As mentioned above, since polymerization proceeds under predetermined pressure and temperature conditions, a high molecular weight (meth)acrylic polymer is formed. Therefore, a polymer layer having a thickness of 100 nm or more, preferably 200 nm or more, and more preferably 500 nm or more can be formed. In addition, the polymer layer is different from the general polymer coating layer, but is formed by using a polymer grafted from a starting group bonded to the surface of the substrate. Therefore, the polymer layer constituting the surface-modified base material produced by the production method of the present invention is expected to exhibit characteristics different from those of general polymer coating layers. In addition, since the polymer layer is formed of a polymer densely elongated in the vertical direction from the surface of the base material, it is expected to exhibit properties such as low friction, protein adsorption inhibition, molecular sieve properties, hydrophilicity, water repellency, etc. more significantly.

Because the reactivity of the starting group is uniform, the molecular weight of the aforementioned polymer produced using a given starting compound having a starting group is the same as the molecular weight of the polymer constituting the polymer layer formed using a given treatment agent having a starting group. , can be considered to be essentially the same. Therefore, by measuring the molecular weight of the polymer produced in the polymerization step of the method for producing a surface-modified substrate of the present invention using GPC or the like, the molecular weight of the polymer constituting the polymer layer formed on the surface of the substrate can be confirmed.

From the thickness L of the polymer layer, the number average molecular weight Mn of the polymer chain, and the density d of the polymer chain, the number of polymer chain branches per unit area (polymer formation density, unit: branch/nm ² ). In the polymer layer constituting the surface-modified base material manufactured by the manufacturing method of the present invention, the polymer formation density is preferably 0.05 branches/nm ² or more, and more preferably 0.1 to 0.7 branches/nm ² . The higher the density of the polymer, the more effectively it can exhibit properties such as high elasticity, ultra-low friction, and molecular sieve effect.

The polymer formation density σ is represented by the following formula (X). In addition, in the following formula (X), N _A represents Avogadro's constant.

σ=dLN _A Mn‧‧‧(X)

The thickness L of the polymer layer can be measured using, for example, an ellipsometer, an electron microscope, or an atomic force microscope. The density d of the polymer chain can be measured in accordance with the method of JIS K 7112:1999, in addition to referring to the density described in conventionally known literature.

According to the manufacturing method of the present invention, a surface-modified substrate with significantly modified surface properties of the substrate can be easily manufactured. Therefore, the manufacturing method of the present invention can be effectively used to manufacture various base materials used in various fields such as medical components, electronic materials, display materials, semiconductor materials, mechanical parts, sliding members, and battery materials.

[Example]

Hereinafter, the present invention will be specifically described based on examples. However, the present invention is not limited to these examples. In addition, "part" and "%" in the examples and comparative examples, It is the quality standard unless otherwise stated.

<Manufacturing of Polymers>

(Example 1)

In a glass sampling bottle, put: 0.002 parts of 2-cyano-2-iodopropane (CP-I), 0.7388 parts of tetrabutylammonium iodide (TBAI), 20.0 parts of methyl methacrylate (MMA), and 20.0 parts of 3-methoxy-N,N-dimethylpropionamide (MDPA). Stir the contents until TBAI is dissolved and homogenized. After blowing in nitrogen, transfer the contents into a resin sampling bottle and lock the cap. Put the sampling bottle with the cover partially wrapped with film and sealed into an aluminum foil bag, remove the air and then seal it.

An aluminum foil bag was placed in a high-pressure device (trade name "PV-400 series", manufactured by Shin Corporation) containing water as a pressurized medium, heated to 80° C., and pressurized to 400 MPa to perform polymerization for 4 hours. A portion of the highly viscous polymer solution in the sampling bottle was taken, and the number average molecular weight (Mn) of the polymer measured in terms of polystyrene was 785,000, and the PDI (Mw/Mn) was 1.56 using GPC using THF as the developing solvent. The polymerization rate calculated from the residual amount of MMA measured with a gas chromatograph (GC) was 64.3%.

(Comparative example 1)

Except that no pressure was applied, polymerization was carried out in the same manner as in Example 1 to obtain a polymer solution with some viscosity. The obtained polymer had an Mn value of 39,000 and a PDI value of 1.12. In addition, the polymerization rate is 15.0%.

(Example 2)

Except that CP-I was replaced with 0.002 parts of ethyl bromoisobutyrate (EBIB), and 0.645 parts of tetrabutylammonium bromide (TBAB) was used instead of TBAI, the rest were the same as in Example 1. Polymerization is carried out to obtain a polymer solution. The Mn system of the obtained polymer was 1,230,000, and the PDI system was 3.25. In addition, the polymerization rate was 71.2%. By replacing iodide salts with bromide salts, polymers with a broad molecular weight distribution and higher molecular weights can be obtained in high yields.

(Example 3)

Except for using EBIB: 0.001 parts, tetraoctylammonium iodide (TOAI): 0.593 parts, MMA: 20 parts, and MDPA: 10 parts, polymerization was carried out in the same manner as in Example 1, and polymerization with almost no fluidity was obtained. material solution. The obtained polymer had an Mn value of 2,420,000 and a PDI value of 1.78. In addition, the polymerization rate was 65.0%. By using bromide as the starting compound and using an iodide salt, a polymer with a somewhat narrow molecular weight distribution and higher molecular weight can be obtained.

(Example 4)

Except that instead of MMA, 35.2 parts of benzyl methacrylate (BzMA) was used, and in place of TOAI, 0.369 parts of TBAI was used, and the polymerization time was set to 6 hours. The rest were the same as in Example 3. Polymerization is carried out to obtain a polymer solution. The obtained polymer had an Mn value of 3,530,000 and a PDI value of 1.49. In addition, the polymerization rate was 71.1%.

(Example 5)

In addition to replacing BzMA, 25.4 parts of lauryl methacrylate (LMA) was used, and Polymerization was carried out in the same manner as in Example 4 except that 25.4 parts of 3-butoxy-N,N-dimethylpropylamine (BDPA) was used instead of MDPA to obtain a polymer solution. The Mn system of the obtained polymer was 450,000, and the PDI system was 1.23. In addition, the polymerization rate was 51.2%.

(Example 6)

Polymerization was carried out in the same manner as in Example 3 except that 25.6 parts of butyl acrylate (BA) was used instead of MMA, 25.6 parts of BDPA was used instead of MDPA, and the polymerization temperature was set to 130°C. , to obtain a more viscous polymer solution. The obtained polymer had an Mn value of 1,030,000 and a PDI value of 1.89. In addition, the polymerization rate was 30.0%.

(Example 7)

Polymerization was carried out in the same manner as in Example 3 except that a high-pressure processing device (trade name "All-round Extractor") manufactured by Toyo High Pressure Co., Ltd. was used and the pressure was increased to 100 MPa to obtain a highly viscous polymer solution. The obtained polymer had an Mn value of 278,000 and a PDI value of 1.92. In addition, the polymerization rate was 45.5%.

(Example 8)

In addition to replacing MDPA, N,N-diethyl-N-methyl-N-2-methoxyethylammonium bis(trifluoromethanesulfonyl) is used instead, and the polymerization time is set to 2 hours. In other cases, polymerization was carried out in the same manner as in Example 3 to obtain a polymer solution. The obtained polymer had an Mn value of 2,600,000 and a PDI value of 1.58. In addition, the polymerization rate was 35.0%.

(Example 9)

Except that butyl acetate was used instead of MDPA, polymerization was carried out in the same manner as in Example 2 to obtain a polymer solution. The obtained polymer had an Mn value of 120,000 and a PDI value of 1.23. In addition, the polymerization rate was 7.5%.

<Manufacturing of Surface Modification Base Material (1)>

(Example 10)

A 1 cm × 1 cm silicon substrate was ultrasonically cleaned with isopropyl alcohol, then a chip cleaner (manufactured by BioForce Nanosciences) was used, and UV ozone irradiation was performed to form and activate hydroxyl groups on the surface of the silicon substrate. Dip the activated silicon substrate into a container filled with: 100 parts of ethanol, 10 parts of 28% ammonia solution, and 1 part of 2-bromo-2-methylpropyloxypropyltrimethoxysilane (BPM) 12 hours. Use a dryer to dry the removed silicon substrate at 80°C for 10 minutes.

Put the above-mentioned silicon substrate into a plastic container that has been filled with: MMA: 20 parts, TOAI: 0.593 parts, EBAI: 0.001 parts, and MDPA: 20 parts, and has a lid. The capped plastic container is placed in a high-pressure device, heated to 80°C, and pressurized to 400 MPa, and polymerized for 6 hours to obtain a surface-modified substrate with a polymer layer formed on the surface of the silicon substrate. In the highly viscous polymer solution generated in the plastic container, the Mn of the polymer is 720,000 and the PDI is 1.86. The resulting polymer is a polymer formed from free starting groups. However, since there are free starting groups on the surface of the silicon substrate, the polymer layer formed on the surface of the silicon substrate is also composed of the same polymer. The film thickness of the polymer layer measured using an ellipsometer (trade name "EC-400", manufactured by J.A. Woollam Co., Ltd.) was 380 nm.

(Example 11)

Except for replacing BPM and using 1 part of 2-iodo-2-methylpropyloxyhexyltriethoxysilane (HIE), the rest were the same as in the aforementioned Example 10, and polymerization was obtained on the surface of the silicon substrate. The surface modification substrate of the physical layer. The resulting polymer had an Mn value of 860,000 and a PDI value of 1.33. In addition, the film thickness of the formed polymer layer was 490 nm.

(Example 12)

Except using a high-pressure treatment device (trade name "Dr.CHEF") manufactured by Kobe Steel Co., Ltd., heating to 80° C. and pressurizing to 600 MPa to perform polymerization for 4 hours, the same procedure as in Example 11 was performed. A surface modification substrate with a polymer layer formed on the surface of a silicon substrate. The resulting polymer has an Mn value of 1,300,000 and a PDI value of 1.66. In addition, the film thickness of the formed polymer layer was 680 nm.

<Synthesis of starting compounds>

(Synthesis example 1)

In a reaction device equipped with a mixer, a reflux condenser, a thermometer, and a nitrogen introduction pipe, 100 parts of propylene glycol monomethyl ether acetate (PGMAc) was placed, heated to 80°C, and nitrogen gas was blown into the reaction device. In another container, put: 50 parts of 2-(2-bromoisobutyloxy)ethyl methacrylate (BBEM) and 50 parts of methacryloxypropyltriethoxysilane (MOPS) , and 1.5 parts of azobisisobutyronitrile (AIBN), stir evenly to prepare a uniform monomer mixture. After adding half the amount of the monomer mixture to the reaction device, the remaining amount was dropped over 2 hours, and then polymerization was performed for 8 hours to obtain a polymer liquid. A portion of the polymer liquid was taken and the measured solid content was 49.2%. It was confirmed that almost all the monomers had been polymerized. The Mn system of the polymer in the polymer liquid is 18,900, and the PDI system is 3.11. The aggregation obtained PGMAc was added to the material solution to dilute it to obtain a starting base polymer 1 solution with a solid content of 15%. The starting group polymer 1 in the starting group polymer 1 solution is a polymer-type treatment agent having a predetermined starting group and an alkoxysilane group.

<Manufacturing of Surface Modification Base Material (2)>

(Example 13)

A glass substrate with a size of 3 cm×3 cm was prepared and activated in the same manner as in Example 10 above. The starting base polymer 1 solution prepared in Synthesis Example 1 was spin-coated on the glass substrate at 2,000 rpm for 30 seconds, first at 90°C for 90 seconds, and then baked at 180°C for 30 minutes. Hardens to form a coating. The coating film thickness measured by an ellipsometer was 1.80 μm. Then, in the same manner as in Example 10 except that the above-mentioned glass substrate on which a coating film has been formed is used, a surface-modified base material in which a polymer layer is formed on the surface of the glass substrate is obtained. The resulting polymer had an Mn value of 790,000 and a PDI value of 1.72. In addition, the film thickness of the polymer layer containing the coating film formed from the starting polymer 1 solution was 2.15 μm. That is, the film thickness of the polymer layer formed on the coating film is 350 nm.

(Example 14)

A silicon carbide substrate (disk-shaped with a diameter of 2 cm and a thickness of 1.0 mm) was prepared and activated in the same manner as in Example 10 above. The substrate was immersed in a solution containing: 100 parts of ethanol, 1 part of 28% ammonia solution, and 10 parts of tetraethoxysilane for 24 hours. After washing the taken-out substrate with ethanol, it was dried at 150°C for 10 minutes. The surface-modified substrate in which the polymer layer was formed on the surface of the silicon carbide substrate was obtained in the same manner as in Example 10 except that the substrate prepared in this way was used and the polymerization time was set to 8 hours. The resulting polymer has an Mn value of 1,480,000 and a PDI value of 1.88. In addition, the polymer layer formed The film thickness is 710nm.

(Example 15)

A metal plate made of SUS402 with a size of 1.5 cm Bake at 180°C for 20 minutes to harden and form a coating film. The film thickness of the formed coating film was 2.6 μm. Then, except that the above-mentioned metal plate on which the coating film has been formed is used, LMA is used instead of MMA, and BDPA is used instead of MDPA, the rest is the same as in the above-mentioned Example 10, and a metal plate formed on the surface of the metal plate is obtained. Surface modification substrate for polymer layer. The resulting polymer has an Mn value of 1,340,000 and a PDI value of 1.55. In addition, the film thickness of the formed polymer layer was 686 nm.

(industrial availability)

The method for producing the polymer of the present invention can be effectively used for coating films such as paints, inks, and coating agents, as well as films, building materials, automotive components, battery components, medical materials, display materials, electronic equipment parts, and the like. Manufacturing methods using high molecular weight polymers. Furthermore, the method for producing a surface-modified base material of the present invention is a method that can effectively use a base material imparted with new properties for use in the production of various industrial materials.

Claims (3)

A method for manufacturing a surface-modified substrate includes: surface treatment of the substrate using a treatment agent having a starting group represented by the following general formula (1) or (2) and an alkoxysilane group, and The steps of obtaining a treated base material; and polymerizing (meth)acrylic monomers under pressure conditions of 100 to 1,000 MPa, temperature conditions of 60°C or above, and in the coexistence of the above treated base material and salts (but , except for the case of polymerization in the presence of a transition metal complex), forming a (meth)acrylic polymer with a number average molecular weight of 100,000 to 10,000,000 in terms of polystyrene as measured by a gel permeation chromatography analyzer, and The step of arranging a polymer layer containing the above-mentioned (meth)acrylic polymer and having a thickness of 100 nm or more on the surface of the above-mentioned treated substrate; wherein the above-mentioned salt is selected from benzyltrimethylammonium chloride, tetrabutyl bromide Among the group consisting of ammonium, tetrabutylammonium iodide, tetraoctylammonium iodide, dodecyltrimethylammonium iodide, stearyltrimethylammonium iodide, and tri(octadecyl)methylammonium iodide at least one;

(In the above-mentioned general formula ( ₁ ), ; R ₂ represents an alkyl group, aryl group, cyano group, acyl group, carboxyl group, ester group, or amide group; "*" represents a bonding position);

₍ In the above general _formula (2), Alkyl, aryl, or acyl group; "*" indicates the bonding position). For example, the method for manufacturing a surface modification substrate according to claim 1 is composed of an alcohol solvent, a glycol solvent, an amide solvent, an ether solvent, a trine solvent, a urea solvent, and an ionic liquid. In at least one organic solvent selected from the group, the (meth)acrylic monomer is polymerized under temperature conditions below the boiling point of the organic solvent. The method for manufacturing a surface-modified substrate according to claim 1 or 2, wherein the (meth)acrylic polymer has a molecular weight distribution (weight average molecular weight/number average molecular weight) of 1.8 or less.