JP7765741B2 - Polymer for water/oil repellent, water/oil repellent composition, and water/oil repellent treated product - Google Patents

Description

The present invention relates to a polymer for use in a water/oil repellent, a water/oil repellent composition, and a water/oil repellent-treated product.

Fluororesins can impart water repellency, oil repellency, stain resistance, release properties, and more to a variety of treated objects. For example, by using a fluorine-containing copolymer with perfluoroalkyl groups, it is possible to impart water and oil repellency to textiles, leather, paper, and other materials.

Patent Document 1 discloses a fluorine-containing copolymer containing structural units derived from a fluorine-containing monomer having a perfluoroalkyl group and structural units derived from a non-fluorine-containing monomer having a long-chain alkyl group and an amide group, urethane group, or urea group.

Japanese Patent Application Laid-Open No. 2020-59800

However, the fluorine-containing copolymer of Patent Document 1 has poor film-forming properties on hydrophilic substrates such as natural fibers and natural leather, making it difficult to impart sufficient water and oil repellency.

In light of the above circumstances, an object of the present invention is to provide a polymer for a water/oil repellent, a water/oil repellent composition, and a water/oil repellent-treated object that can impart excellent water/oil repellency to treated objects.

That is, the present invention relates to a fluorine-containing copolymer for use in a water/oil repellent agent, which comprises a structural unit derived from a fluorine-containing monomer (a) represented by the following formula (1) and a structural unit derived from a non-fluorine-containing monomer (b1) represented by the following formula (2), wherein, when the total amount of structural units derived from all monomers is taken as 100 parts by mass, the mass of the structural unit derived from the monomer (a) is 10 to 90 parts by mass and the mass of the structural unit derived from the monomer (b1) is 10 to 90 parts by mass:
(In formula (1), ^R1 represents a hydrogen atom or a methyl group, l represents an integer of 0 to 4, and m represents an integer of 0 to 5.)
(In formula (2), ^R2 represents a hydrogen atom, a methyl group, or a halogeno group; ^R3 represents an alkyl group having 12 to 24 carbon atoms; A represents an alkylene group having 1 to 10 carbon atoms; X represents 0 or 1; and Y represents a hydroxyurethane structure selected from the group consisting of formulas (3), (4), (5), and (6) below.)

The present invention also relates to a water/oil repellent composition containing the polymer for water/oil repellents and a liquid medium.

Furthermore, the present invention relates to a water- and oil-repellent treated article to which the polymer for water- and oil-repellent agents is attached.

The present invention provides a polymer for a water/oil repellent, a water/oil repellent composition, and a water/oil repellent-treated product with excellent water/oil repellency, which can impart excellent water/oil repellency to substrates such as synthetic fibers, natural fibers, and natural leather.

<Fluorine-containing monomer (a)>
The fluorine-containing monomer (a) is a monomer represented by the following formula (1):
(In formula (1), ^R1 represents a hydrogen atom or a methyl group, l represents an integer of 0 to 4, and m represents an integer of 0 to 5.) In addition, in formula (1), l is preferably an integer of 1 or 2, and m is preferably an integer of 3 to 5.

Specific examples of compounds represented by fluorine-containing monomer (a) include 2-(perfluorohexyl)ethyl (meth)acrylate, 2-(perfluorobutyl)ethyl (meth)acrylate, 3-(perfluorohexyl)propyl (meth)acrylate, 4-(perfluorohexyl)butyl (meth)acrylate, and 2,2,2-trifluoroethyl (meth)acrylate. 2-(perfluorohexyl)ethyl (meth)acrylate and 2-(perfluorobutyl)ethyl (meth)acrylate are preferred, with 2-(perfluorohexyl)ethyl methacrylate being more preferred due to its excellent water and oil repellency. The fluorine-containing monomer (a) may be used alone or in combination of two or more types.

<Fluorine-free Monomer (b1)>
The non-fluorine-containing monomer (b1) is a monomer represented by the following formula (2), and by having a hydroxyurethane structure, it is possible to improve the film-forming properties of the polymer on the object to be treated and to impart excellent water repellency. The non-fluorine-containing monomer (b1) may be used alone or in combination of two or more kinds.
(In formula (2), ^R2 represents a hydrogen atom, a methyl group, or a halogeno group; ^R3 represents an alkyl group having 12 to 24 carbon atoms; A represents an alkylene group having 1 to 10 carbon atoms; X represents 0 or 1; and Y represents a hydroxyurethane structure selected from the group consisting of formulas (3), (4), (5), and (6) below.)

In formula (2), R ² is preferably a hydrogen atom or a methyl group, since this facilitates the polymerization reaction.

In formula (2), ^R3 represents an alkyl group having 12 to 24 carbon atoms. By having an alkyl group having 12 to 24 carbon atoms, crystallization of the side chain is induced, and a dense film in which the alkyl groups are aligned can be formed on the surface of the object to be treated, thereby exhibiting excellent water repellency. Examples of alkyl groups having 12 to 24 carbon atoms include linear or branched alkyl groups having 12 to 24 carbon atoms. In terms of excellent water repellency and ease of industrial production, the number of carbon atoms in ^R3 is preferably 12 to 22, and more preferably 18 to 22. Furthermore, it is more preferable that ^R3 is a linear alkyl group.

In formula (2), A represents an alkylene group having 1 to 10 carbon atoms, and X represents 0 or 1. The number of carbon atoms in A is preferably 1 or more, and preferably 4 or less.

In formula (2), Y is a hydroxyurethane structure selected from the group consisting of formulas (3), (4), (5), and (6). From the viewpoint of superior water repellency, the structure of formula (3) or formula (4) is particularly preferred for Y.

It is particularly preferable to use a compound with a molecular weight in the range of 355 to 800 as the non-fluorine-containing monomer (b1).

The method for producing the non-fluorine-containing monomer (b1) is not particularly limited, and it can be produced by any known method. For example, it can be obtained by an addition reaction between a compound having both a (meth)acryloyl group and a cyclic carbonate group and an amine compound having an alkyl group having 12 to 24 carbon atoms.

<Vinyl Monomer (b2)>
The vinyl monomer (b2) is a vinyl group-containing monomer copolymerizable with the fluorine-containing monomer (a) and the non-fluorine-containing monomer (b1). Examples of the vinyl monomer (b2) include (meth)acrylic acid ester compounds, (meth)acrylamide compounds, aromatic alkenyl compounds, halogenated vinyl compounds, and vinyl cyanide compounds. Among these, it is preferable to copolymerize at least one (meth)acrylic acid ester compound or (meth)acrylamide compound. The vinyl monomer (b2) may be used alone or in combination of two or more.

The (meth)acrylic acid ester compound or (meth)acrylamide compound is a compound having at least one vinyl group, and it is preferable to use a compound represented by the following formula (7).
(In formula (7), ^R4 represents a hydrogen atom, a methyl group, or a halogeno group; Z represents an oxygen atom or a nitrogen atom; ^R5 represents a hydrogen atom or an optionally substituted hydrocarbon group having 1 to 22 carbon atoms; and n represents 1 when Z is an oxygen atom, or 2 when Z is a nitrogen atom.)

In formula (7), the hydrocarbon group of ^R5 may have a substituent. The compound represented by formula (7) used as the vinyl monomer (b2) preferably contains at least one compound in which ^R5 is a hydrocarbon group having a substituent and at least one compound in which ^R5 is a hydrocarbon group without a substituent.

Examples of compounds in which R ⁵ is a hydrogen atom include (meth)acrylic acid and (meth)acrylamide.

Examples of the unsubstituted hydrocarbon group in ^R5 include linear, branched, and cyclic alkyl groups having 1 to 22 carbon atoms.

Specific compounds having a linear or branched alkyl group having 1 to 22 carbon atoms include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, and lauric acid. Examples of suitable acrylates include methyl (meth)acrylate, hexadecyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, docosyl (meth)acrylate, dimethyl (meth)acrylamide, and diethyl (meth)acrylamide. However, methyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and isostearyl (meth)acrylate are preferred because of their excellent water and oil repellency and ease of copolymerization with the non-fluorine-containing monomer (b1). Stearyl (meth)acrylate is even more preferred.

The unsubstituted cyclic hydrocarbon group for ^R5 may, for example, be a monocyclic or polycyclic alkyl group having 3 to 22 carbon atoms. Examples include cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, and 1-adamantyl (meth)acrylate. From the viewpoint of improving the durability of water and oil repellency, cyclohexyl (meth)acrylate and isobornyl (meth)acrylate are preferred. Cyclohexyl (meth)acrylate is even more preferred.

When the hydrocarbon group in ^R5 has a substituent, the substituent may be at least one selected from the group consisting of a hydroxyl group, an ether group, an epoxy group, a carbonyl group, an ester group, an amide group, an isocyanate group, a urethane group, a urea group, a vinyl group, an amino group, an onium base, a heterocyclic group, an aryl group, an organosiloxy group, and a polydimethylsiloxane group. Among these substituents, ^R5 is preferably a hydrocarbon group having an aryl group, a polydimethylsiloxane group, a hydroxyl group, or an ether group. The molecular weight of the hydrocarbon group-containing monomer having a polydimethylsiloxane group is preferably 1,000 to 30,000.

Specific compounds in which the hydrocarbon group has a substituent include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, glycerol mono(meth)acrylate, polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, methoxyethyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, glycidyl (meth)acrylate, (2-oxo-1,3-dioxolan-4-yl)methyl (meth)acrylate, 2-isocyanatoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, and trimethylammonium (meth)acrylate chloride. ethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, 4-hydroxyphenyl (meth)acrylate, "Placcel FM series" (trade name, ε-caprolactone adduct of 2-hydroxyethyl methacrylate, manufactured by Daicel Corporation), 3-(trimethoxysilyl)propyl (meth)acrylate, "Silaplane FM-0721 (trade name, polydimethylsiloxane group-containing macromonomer (molecular weight 5,000), manufactured by JNC Corporation)", "Silaplane FM-0725 (trade name, polydimethylsiloxane group-containing macromonomer (molecular weight 10,000), manufactured by JNC Corporation)", "Silaplane FM-7721 (trade name, polydimethylsiloxane group-containing bifunctional macromonomer (molecular weight 5,000), manufactured by JNC Corporation)", diacetone (meth)acrylamide, and N-methylol (meth)acrylamide. In view of their good water and oil repellency and ease of copolymerization with the non-fluorine-containing monomer (b1), 2-hydroxyethyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate, benzyl (meth)acrylate, "Silaplane FM-0721 (manufactured by JNC Corporation, polydimethylsiloxane group-containing macromonomer (molecular weight 5,000)), trade name)," "Silaplane FM-0725 (manufactured by JNC Corporation, polydimethylsiloxane group-containing macromonomer (molecular weight 10,000)), trade name)," diacetone (meth)acrylamide, and N-methylol (meth)acrylamide are preferred.

Examples of aromatic alkenyl compounds used as vinyl monomer (b2) include styrene, α-methylstyrene, and p-methoxystyrene.

Examples of halogenated vinyl compounds used as the vinyl monomer (b2) include vinyl fluoride, vinyl chloride, vinyl bromide, and vinyl iodide.

Examples of vinyl cyanide compounds used as vinyl monomer (b2) include (meth)acrylonitrile.

<Composition ratio of polymer for water and oil repellent>
The polymer for the water/oil repellent agent preferably contains a fluorine-containing copolymer containing structural units derived from the fluorine-containing monomer (a) and structural units derived from a non-fluorine-containing monomer (b1), or a fluorine-containing copolymer containing structural units derived from the fluorine-containing monomer (a), structural units derived from a non-fluorine-containing monomer (b1), and structural units derived from a vinyl monomer (b2).

In the fluorine-containing copolymer, when the total amount of structural units derived from all monomers is taken as 100 parts by mass, the mass of the structural units derived from monomer (a) is 10 to 90 parts by mass, and the mass of the structural units derived from monomer (b1) is 10 to 90 parts by mass. In the fluorine-containing copolymer, when the total amount of structural units derived from all monomers is taken as 100 parts by mass, from the viewpoints of water and oil repellency and solubility, the mass of the structural units derived from monomer (a) is preferably 30 to 80 parts by mass, more preferably 40 to 80 parts by mass, and the mass of the structural units derived from monomer (b1) is preferably 10 to 70 parts by mass, more preferably 20 to 60 parts by mass. When the mass of the structural units derived from monomer (a) is less than 10 parts by mass, the water and oil repellency tends to decrease,
If the amount is more than 90 parts by mass, the solubility of the fluorine-containing copolymer in hydrocarbon solvents tends to decrease significantly.

Furthermore, when the fluorine-containing copolymer contains structural units derived from vinyl monomer (b2), from the viewpoints of water and oil repellency and solubility, the mass of the structural units derived from monomer (b2) is preferably 80 parts by mass or less, more preferably 1 to 50 parts by mass, and even more preferably 5 to 30 parts by mass, when the total amount of structural units derived from all monomers is taken as 100 parts by mass.

<Method of manufacturing polymer for water and oil repellent>
The polymer for water and oil repellents can be obtained by radical polymerization of a monomer mixture containing at least a fluorine-containing monomer (a) and a non-fluorine-containing monomer (b1). The polymerization method is not particularly limited, and known polymerization methods such as solution polymerization, emulsion polymerization, and suspension polymerization can be used.

Polymerization initiators that can be used include organic peroxides, azo compounds, and persulfates. Specific examples of polymerization initiators include tert-butyl peroxypivalate, tert-hexylperoxyneodecanate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, di-3,5,5-trimethylhexanoyl peroxide, 2,2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2-methylpropionamidine) dihydrochloride, and ammonium persulfate. The amount of polymerization initiator used can be appropriately determined depending on the combination of monomers used and reaction conditions.

In the solution polymerization method, various monomers are dissolved in any solvent in the presence of a polymerization initiator, and after replacing the atmosphere with nitrogen, the mixture is heated and stirred to polymerize.

In emulsion polymerization, various monomers are emulsified in water or a mixture of organic solvents and water in the presence of a polymerization initiator and a surfactant, and then the mixture is heated and stirred after nitrogen substitution to polymerize the monomers.

The arrangement of the constituent units of each monomer in the polymer for water and oil repellents is not particularly limited and may be random, block, graft, etc.

<Weight average molecular weight>
The polymer for the water/oil repellent agent is a polymer having a weight-average molecular weight in polystyrene equivalent of 5,000 to 2,000,000, preferably in the range of 10,000 to 1,900,000 from the viewpoint of good water/oil repellency, and more preferably in the range of 30,000 to 1,800,000. If the weight-average molecular weight is within this range, the uniformity of the coating made of the polymer is improved, and the water/oil repellency is good.

A chain transfer agent may be used during polymerization to adjust the molecular weight of the polymer for water and oil repellents. Examples of chain transfer agents include lauryl mercaptan and tert-butyl alcohol. The amount of chain transfer agent used can be set appropriately depending on the combination of monomers used and reaction conditions, etc.

<Water/Oil Repellent Composition>
The water/oil repellent composition can be produced by mixing a polymer for the water/oil repellent with a liquid medium. By preparing the water/oil repellent composition, it is possible to facilitate adhesion of the polymer for the water/oil repellent to the object to be treated.

There are no particular limitations on the liquid medium, as long as it dissolves or disperses the polymer. Examples include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, water, ethanol, n-propanol, isopropyl alcohol, propylene glycol, dipropylene glycol, tripropylene glycol, dipropylene glycol monomethyl ether, ethyl acetate, butyl acetate, tetrahydrofuran, dimethylformaldehyde, toluene, xylene, n-hexane, isohexane, n-heptane, cyclopentane, cyclohexane, methylcyclohexane, and isoparaffin-based solvents. Among these liquid media, aliphatic hydrocarbon solvents are preferred in terms of maintaining the texture of the treated object and preventing deterioration. Preferred are n-hexane, isohexane, n-heptane, cyclopentane, cyclohexane, and methylcyclohexane, with n-hexane, n-heptane, and cyclohexane being particularly preferred. These liquid media may be used alone or in combinations of two or more.

When the total amount of the polymer for the water/oil repellent and the liquid medium is 100 parts by mass, the content of the polymer for the water/oil repellent is preferably 0.1 to 10 parts by mass, and more preferably 1 to 10 parts by mass.

The water/oil repellent composition may further contain additives as long as the effects of the present invention are not impaired. For example, if the total amount of the polymer and liquid medium is 100 parts by mass, the content of the additive is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less.

Additives include polymers other than those for water and oil repellents that can impart water and oil repellency, crosslinking agents, antibacterial and deodorizing agents, flame retardants, antistatic agents, fabric softeners, and wrinkle-resistant agents. Adding a crosslinking agent is particularly preferable when treating fabrics and clothing to prevent a decrease in water and oil repellency due to washing. Examples of crosslinking agents include methylol melamine, compounds containing at least one of an isocyanate group, and a blocked isocyanate group. By attaching a crosslinking agent to the object to be treated and then heat treating it, water and oil repellency can be maintained even after washing.

<Water and oil repellent treated material>
The polymer for water/oil repellents can be used to impart water/oil repellency to a treated object, thereby producing a water/oil repellent-treated object. Examples of applicable treated objects include natural fibers such as cotton, linen, and silk; recycled fibers such as rayon and cupra; semi-synthetic fibers such as acetate and triacetate; synthetic fibers such as polyamide, polyester, polyacrylonitrile, polypropylene, polyvinyl chloride, and polyvinyl alcohol; natural leather; synthetic leather; fur; paper; wood; blends of these fibers; and fabrics, clothing, and shoes made from these fibers; glass fiber; glass; brick; cement; metal; and plastic. Among these, the polymer is particularly effective on synthetic fibers, natural fibers, and natural leather.

The water- and oil-repellent treatment can be applied by common methods such as spray coating, bar coating, and dip coating. After applying the water- and oil-repellent treatment to the object to be treated, it is preferable to dry the object by volatilizing the liquid medium at room temperature or by heat treatment, etc. There are no particular restrictions on the temperature conditions during drying, but considering the thermal degradation of the object, it is preferable to use a temperature between 20°C and 200°C, preferably between 50°C and 150°C.

Example 1
First, 120 g of cyclohexane was charged into a 500 mL four-neck flask equipped with a thermometer, a stirrer, and a reflux condenser, and the atmosphere inside the flask was replaced with nitrogen. Next, a monomer solution consisting of 30 g of 2-(perfluorohexyl)ethyl methacrylate (FMAC6) (monomer (a)), 70 g of "HUMA-2" (monomer (b1)) listed in Table 1, and 94.7 g of cyclohexane, and a polymerization initiator solution consisting of 3.3 g of tert-hexyl peroxyneodecanate and 15 g of cyclohexane were prepared. The temperature inside the reaction vessel was raised to 55°C, and the monomer solution and the polymerization initiator solution were simultaneously added dropwise over 2 hours. After the dropwise addition was completed, the mixture was allowed to react at 55°C for 5 hours, then the temperature was raised to 70°C and allowed to react for an additional 2 hours, yielding a solution containing a polymer.

Table 2 shows the composition of each component in Example 1. As shown in Table 2, the mass ratio ((a)/(b1)/(b2)) of the structural units derived from the fluorine-containing monomer (a), the structural units derived from the non-fluorine-containing monomer (b1), and the structural units derived from the vinyl monomer (b2) in the polymer obtained in Example 1 was 30/70/0.

(Examples 2 to 19)
In Examples 2 to 19, the types and amounts of the monomers were changed to those shown in Tables 2 to 5. Each monomer (b1) is as shown in Table 1. Except for this, the polymer for a water repellent of each Example was produced in the same manner as in Example 1.

(Example 20)
First, a 1-L plastic container was charged with a mixture consisting of 60 g of 2-(perfluorohexyl)ethyl methacrylate (FMAC6), 25 g of "HUMA-2" listed in Table 1, 7.0 g of stearyl methacrylate (SMA), 7.0 g of cyclohexyl methacrylate (CHMA), 1.0 g of N-methylolacrylamide (N-MAM), 31.7 g of tripropylene glycol, and 258 g of water, and an emulsifier mixture consisting of 2.8 g of polyoxyethylene lauryl ether, 2.8 g of polyoxyethylene isodecyl ether, and 3.5 g of octadecyltrimethylammonium chloride. The mixture was heated to 60°C, mixed and stirred for 1 minute at 2,000 rpm using a homomixer, and then emulsified and dispersed by ultrasonic irradiation. Next, the emulsified dispersion was transferred to a 500 mL four-neck flask equipped with a thermometer, a stirrer, and a reflux condenser. After purging with nitrogen, 0.2 g of lauryl mercaptan and 1.0 g of 2,2′-azobis(2-methylpropionamidine) dihydrochloride were added to the dispersion, and the mixture was allowed to react at 60° C. for 6 hours to obtain an aqueous dispersion containing a polymer.

(Comparative Examples 1 to 4)
In Comparative Examples 1 to 4, polymers of each Comparative Example were produced in the same manner as in Example 1, except that the types and amounts of the monomers were changed to those shown in Table 6.

The weight-average molecular weights of the polymers obtained in Examples 1 to 20 and Comparative Examples 1 to 4 were measured. Specifically, a TOSOH HLC-8320GPC was used as the GPC system, and two TOSOH TSKgel Super Multipore HZ-M columns and one TOSOH TSKgel Super H-RC column were installed in series. The column temperature was set to 40°C, the reference material was polystyrene, the developing solvent was tetrahydrofuran, and the developing solvent was flowed at a flow rate of 1 ml/min. 0.1 ml of a sample solution with a sample concentration of 0.1% by mass was injected, and measurements were performed using the EcoSEC-Work Station GPC calculation program.

(Test piece preparation)
The evaluation substrates used were polyester fabric, cotton fabric, and cowhide.

The polymers of Examples 1 to 19 and Comparative Examples 1 to 4 were diluted with cyclohexane as a liquid medium to produce solutions with a concentration of 2.0% by mass (water- and oil-repellent compositions). Polyester taffeta fabric and cotton fabric were immersed in each solution and then heated and dried at 150°C for 3 minutes to produce test pieces (water- and oil-repellent treated products). Cowhide leather was sprayed with each solution using a spray gun, and then dried at room temperature to produce test pieces (water- and oil-repellent treated products).

The polymers according to each of the above Examples 20 were diluted with water as a liquid medium to produce dispersions (water- and oil-repellent compositions) with a concentration of 2.0% by mass. Polyester taffeta fabric and cotton fabric were immersed in each dispersion, which was then heated and dried at 150°C for 3 minutes to produce test pieces (water- and oil-repellent treated products). Cowhide was sprayed with each dispersion using a spray gun, and then dried at room temperature to produce test pieces (water- and oil-repellent treated products).

(Water repellency test)
The water repellency of each test piece was evaluated in accordance with JIS L 1092. A spray tester AW-5 (manufactured by Intec Co., Ltd.) was used as the testing machine. The test piece was attached to the testing machine, and 250 mL of water was sprayed on it. The wet state of the test piece after spraying was evaluated according to the criteria shown in Table 7. A higher value indicates better water repellency. The target value for water repellency was 90 or more for polyester fabric, and 80 or more for cotton fabric and cowhide, which are difficult to impart water repellency to.

(Oil repellency test)
The oil repellency test was conducted based on AATCC Test Method 118-1997. 50 μL of a hydrocarbon solvent (Table 8) was gently dropped onto the surface of the test piece, and the state of the droplet was evaluated after 30 seconds. The grade of the hydrocarbon solvent with the lowest surface tension that did not penetrate the substrate was used as the evaluation score. The higher the value, the better the oil repellency. The target oil repellency value was 5 or higher for polyester fabric, and 3 or higher for cotton fabric and cowhide, which are difficult to impart oil repellency to.

[Evaluation results]
Tables 2 to 5 show the evaluation results of Examples 1 to 20, and Table 6 shows the evaluation results of Comparative Examples 1 to 4.

However, the substituents of the formula (8) used in the monomer (b2) in Table 1 are as follows:

The abbreviations shown in Tables 2 to 6 are as follows:
FMAC6: 2-(perfluorohexyl)ethyl methacrylate FAC6: 2-(perfluorohexyl)ethyl acrylate SMA: stearyl methacrylate CHMA: cyclohexyl methacrylate BzMA: benzyl methacrylate FM0721: Silaplane FM0721 manufactured by JNC (polydimethylsiloxane group-containing macromonomer, molecular weight 5,000)
FM0725: JNC Silaplane FM0721 (polydimethylsiloxane group-containing macromonomer, molecular weight 10,000)
HEMA: 2-hydroxyethyl methacrylate PME400: methoxypolyethylene glycol methacrylate (average number of moles of ethylene oxide added: 9)
DAAM: Diacetone acrylamide N-MAM: N-methylol acrylamide

As is clear from the results in Tables 2 to 5, Examples 1 to 20 demonstrated excellent water and oil repellency against a variety of substrates.

On the other hand, as is clear from Table 6, Comparative Examples 1 to 4 had insufficient water repellency or oil repellency.

Specifically, in Comparative Example 1, the fluorine-containing copolymer did not contain any structural units derived from the fluorine-containing monomer (a), and therefore the oil repellency was poor. In Comparative Example 2, the proportion of structural units derived from the fluorine-containing monomer (a) in the fluorine-containing copolymer was excessively high, and therefore the fluorine-containing copolymer was insoluble in hydrocarbon solvents. In Comparative Examples 3 and 4, the fluorine-containing copolymer did not contain any structural units derived from the non-fluorine-containing monomer (b1), and therefore the water and oil repellency to natural fibers and natural leather was poor.

Claims (4)

A fluorine-containing copolymer comprising a structural unit derived from a fluorine-containing monomer (a) represented by the following formula (1) and a structural unit derived from a non-fluorine-containing monomer (b1) represented by the following formula (2),
A polymer for a water/oil repellent agent, characterized in that, when the total amount of structural units derived from all monomers is taken as 100 parts by mass, the mass of the structural unit derived from the monomer (a) is 10 to 90 parts by mass, and the mass of the structural unit derived from the monomer (b1) is 10 to 90 parts by mass.
(In formula (1), ^R1 represents a hydrogen atom or a methyl group, l represents an integer of 0 to 4, and m represents an integer of 0 to 5.)
(In formula (2), ^R2 represents a hydrogen atom, a methyl group, or a halogeno group; ^R3 represents an alkyl group having 12 to 24 carbon atoms; A represents an alkylene group having 1 to 10 carbon atoms; X represents 0 or 1; and Y represents a hydroxyurethane structure selected from the group consisting of formulas (3), (4), (5), and (6) below.)
It contains a structural unit derived from a vinyl monomer (b2) represented by the following formula (7),
The polymer for a water/oil repellent according to claim 1, characterized in that the mass of the structural units derived from the monomer (b2) is 80 parts by mass or less when the total amount of structural units derived from all monomers is 100 parts by mass.
(In formula (7), ^R4 represents a hydrogen atom, a methyl group, or a halogeno group; Z represents an oxygen atom or a nitrogen atom; ^R5 represents a hydrogen atom or an optionally substituted hydrocarbon group having 1 to 22 carbon atoms; and n represents 1 when Z is an oxygen atom, or 2 when Z is a nitrogen atom.) A water/oil repellent composition comprising the polymer for water/oil repellents according to claim 1 or 2 and a liquid medium. A water- and oil-repellent treated article characterized by having the water- and oil-repellent polymer of claim 1 or 2 adhered thereto.