JPH08134143A - Fluorine-containing vinyl ether copolymer - Google Patents

Abstract

PURPOSE: To obtain the subject copolymer having a specific average molecular weight and containing a specific vinyl ether, a fluorine-containing vinyl ether and vinyl silane as units and excellent in curing property in the air, weather resistance, water-repellent and oil-repellent property and solvent resistance and useful for coating, etc. CONSTITUTION: This copolymer having 2000-200000 number-average molecular weight is obtained by randomly arranging (A) 20-60mol% of a vinyl ether unit of the formula, CH2 C(OR)H (R is an alkyl), (B) 30-70mol% of a fluorine- containing vinyl ether unit of formula I [Rf is a perfluoroalkyl or a group of formula II (p>=0)] and (C) 1-25mol% of a vinylsilane unit of formula III [at least one of X<1> to X<3> is a group is a group capable of forming OH by hydrolysis (e.g. alkoxy, a halogen or a substituted amino)].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copolymer which is soluble in an organic solvent and has a curing function at room temperature and which is excellent in water / oil repellency and chemical resistance. More specifically, it relates to copolymers with vinyl ether, vinyl silane and fluorine-containing vinyl ether monomers.

[0002]

2. Description of the Related Art Homopolymers and copolymers of vinyl ester, acrylic ester, vinyl ether monomer and the like have good solubility in hydrocarbon solvents and are applied to various substrates. Since it sometimes has good adhesiveness, it is widely used as a resin useful in various applications such as paints and surface coating agents. However, resins made of these monomers have low water resistance and large water absorption, and have poor weather resistance and other physical properties in moist air or water, which poses a serious problem depending on the application.

On the other hand, fluoropolymers are extremely stable both thermally and chemically, and are excellent in weather resistance, water resistance, chemical resistance and solvent resistance, so that they are used as surface treatment agents for various substrates. It is suitable. However, conventionally known fluoropolymers are difficult to dissolve in an organic solvent due to the above-mentioned properties, it is difficult to form a coating film, and it is difficult to use as a paint.

Therefore, in recent years, attempts have been made to develop a fluoropolymer which is soluble in a solvent and has weather resistance, water / oil repellency, chemical resistance and solvent resistance after coating.

For example, JP-A-57-34107 discloses a quaternary copolymer composed of fluoroolefin, cyclohexyl vinyl ether, alkyl vinyl ether and hydroxyl vinyl ether, and this copolymer is soluble in an organic solvent. It is also described that it can be cured at room temperature. However, these copolymers have a drawback that most of the fluorine atoms are present in the main chain, so that they have not yet exhibited water and oil repellency.

Further, it has been proposed to use an acrylate ester having a perfluoroalkyl group as a side chain as a fluorine-containing monomer in order to impart water repellency and oil repellency (JP-A-49-6075). ) However, since this monomer has a perfluoroalkyl group bonded through an ester bond, the resulting copolymer is hydrolyzed so that the perfluoroalkyl group is released from the copolymer, resulting in water and oil repellency. Is likely to decrease, and there are drawbacks in chemical resistance and weather resistance.

[0007]

Accordingly, the resin obtained from these vinyl monomers and fluorine-based monomers is soluble in an organic solvent and has a good film-forming ability without impairing the original characteristics of the resin. It has been desired to develop a copolymer having good weather resistance, water / oil repellency, chemical resistance, solvent resistance and the like.

[0008]

Means for Solving the Problems As a result of intensive research to solve the above-mentioned problems, the present inventors have found that a fluorine-containing vinyl ether monomer having a specific structure, a vinyl ether monomer and a vinyl silane monomer are obtained. The copolymerized copolymer is
It is soluble in organic solvents and has excellent film-forming ability. In addition, the film formed by this copolymer is cured into a film with excellent weather resistance, water / oil repellency, chemical resistance and solvent resistance. The inventors have found that it is possible and have completed the present invention.

That is, the present invention has the general formula (1)

[0010]

Embedded image

(Wherein R is an alkyl group) 20 to 60 mol% of a vinyl ether monomer unit represented by the general formula (2).

[0012]

Embedded image

(Wherein R _f is a perfluoroalkyl group, or

[0014]

Embedded image

(However, p is an integer of 0 or more.). ) Fluorine-containing vinyl ether monomer unit 3 represented by
0-70 mol% and general formula (3)

[0016]

[Chemical 4]

(However, X ¹ , X ² , and X ³ are the same or different, and at least one is a group capable of being hydrolyzed to form a hydroxyl group.) It is a fluorine-containing vinyl ether copolymer having a number average molecular weight of 2,000 to 200,000 randomly arranged with mol%.

Among the monomer units constituting the fluorine-containing vinyl ether copolymer of the present invention, the vinyl ether monomer unit is represented by the general formula (1).

[0019]

[Chemical 9]

(However, R is an alkyl group.) In the general formula (1), the alkyl group represented by R is not particularly limited, but in view of polymerizability and practicality, it is a methyl group. A chain alkyl group such as a group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a tert-butyl group, and an n-octyl group, and a cyclic alkyl group such as a cyclopentyl group and a cyclohexyl group having 1 to 10 carbon atoms It is preferably in the range. In the fluorine-containing vinyl ether copolymer of the present invention, the monomer units represented by the general formula (1) may be copolymerized not only in the same kind but also in combination of two or more kinds.

Next, among the monomer units constituting the fluorine-containing vinyl ether copolymer of the present invention, the fluorine-containing vinyl ether monomer unit is represented by the general formula (2).

[0022]

[Chemical 10]

In the general formula (2), R _f is a perfluoroalkyl group, or

[0024]

[Chemical 11]

(However, p is an integer of 0 or more.). The carbon number of the perfluoroalkyl group in R _f is not particularly limited, but it is preferably in the range of 1 to 12 in consideration of the effect of water repellency and the cost or the availability of raw materials. _{Specifically, -CF 3, -CF 2 CF 3} , -
_{CF 2 CF 2 CF 3, -CF} 2 (CF 2 CF 2) q CF 3 (q =
1-4) etc. can be mentioned. Further, particularly when improving the oil repellency, the carbon number is preferably 6 to 12. Also,
the above

[0026]

[Chemical 12]

In the group represented by p, p is an integer of 0 or more, preferably 0 to 3.

Further, among the monomer units constituting the fluorine-containing vinyl ether copolymer of the present invention, the vinylsilane monomer unit is represented by the general formula (3).

[0029]

[Chemical 13]

(However, X ¹ , X ² , and X ³ are the same or different, and at least one is a group capable of being hydrolyzed to a hydroxyl group.) In the general formula (3), X ¹ and X ^At least one of the groups represented by ² and X ³ is a group that can be hydrolyzed to form a hydroxyl group. Specifically, an alkoxy group, a halogen, a substituted amino group and the like are preferable. As the alkoxy group, those having 1 to 5 carbon atoms such as methoxy group, ethoxy group and butoxy group are preferable. Examples of the halogen include chlorine, bromine, iodine and the like, among which chlorine is preferable. Examples of the substituted amino group include those having 1 to 5 carbon atoms such as methylamino group, ethylamino group and propylamino group. Here, an alkoxy group is preferable in consideration of the curing speed and the like. It is sufficient that at least one group capable of forming a hydroxyl group is bonded to a silicon atom, but preferably two groups, and more preferably all of them are the group. Further, among the groups represented by X ¹ , X ² and X ³ , the group other than the group which can be hydrolyzed to a hydroxyl group is not particularly limited, but specifically, a methyl group, an ethyl group or an ethyl group can be used. A chain-like alkyl group such as a group, an isopropyl group, and a butyl group is preferable. The number of carbon atoms is preferably in the range of 1 to 5 so as not to adversely affect the crosslinked structure.

In the present invention, the vinyl ether monomer unit represented by the general formula (1), the fluorine-containing vinyl ether monomer unit represented by the formula (2), and the vinyl silane monomer represented by the general formula (3) are used. The content of the monomer unit is in the range of 20 to 60 mol%, preferably 30 to 50 mol%, of the vinyl ether monomer unit represented by the general formula (1), and the fluorine-containing vinyl ether represented by the formula (2). Monomer unit is 30 to 70 mol%, preferably 40 to 60
It is in the range of mol% and the vinylsilane monomer unit represented by the general formula (3) is 1 to 25 mol%, preferably 1.5 to
It is in the range of 15 mol%. The relationship of these contents is illustrated in FIG. Here, the proportion of the vinyl ether monomer unit represented by the general formula (1) is 2 from the balance of the proportion with the fluorine-containing vinyl ether monomer in the copolymer.
When it is less than 0 mol%, it becomes difficult to dissolve in a general solvent, and when it is more than 60 mol%, the water repellency and oil repellency of the original function are deteriorated. Also, regarding the fluorine-containing vinyl ether monomer represented by the general formula (2), when it is less than 30 mol%, the curing such as water repellency and oil repellency of the original function is small, and when it is more than 70 mol%, It becomes difficult to dissolve in the solvent and the solvent is limited. Further, regarding the vinylsilane monomer unit represented by the general formula (3),
If this ratio is less than 1 mol%, curing will be extremely slow when a coating film is formed, and if it exceeds 25 mol%, the coating film will become brittle and peeling will occur.

The fluorine-containing vinyl ether copolymer of the present invention is a fluorine-containing vinyl ether copolymer having a number average molecular weight of 2,000 to 200,000 in which the above-mentioned monomer units are randomly arranged. .

The fluorine-containing vinyl ether copolymer of the present invention has a proton nuclear magnetic resonance spectrum (hereinafter, ¹ H-NM
The compound can be easily identified by measuring R). That is, the fluorine-containing vinyl ether copolymer of the present invention first has the general formula (2) at about δ4.2 ppm.

[0034]

Embedded image

A peak based on the proton of the methylene group adjacent to the ether bond of the fluorine-containing vinyl ether monomer unit represented by is observed.

Further, in the fluorine-containing vinyl ether copolymer of the present invention, a vinyl ether monomer unit and a vinylsilane monomer unit are included.

[0037]

[Chemical 15]

[0038]

Embedded image

The peaks of the protons constituting each of the methine groups are observed. Here, the observed wavelength of this peak varies depending on the types of monomer units bonded before and after each of the vinyl ether monomer unit and the vinylsilane monomer unit. That is, when the fluorine-containing vinyl ether monomer units are arranged before and after the vinyl ether monomer unit and the vinylsilane monomer unit, the peaks of the methine group shift, respectively. Therefore, four different peaks are observed depending on the arrangement of the following vinyl ether monomer unit and other monomer units before and after the vinyl silane monomer unit (herein, fluorine-containing vinyl ether). The bond form of the monomer unit is

[0040]

[Chemical 17]

Although there are two orientations of ¹ H-NMR, the ¹ H-NMR peak is hardly affected by this difference in the orientation of the bond. ).

1) A or C- [A (C)]-A or CA A: vinyl ether monomer unit 2) B- [A (C)]-A or CB: fluorine-containing vinyl ether unit 3) A or C- [A (C)]-B monomer unit 4) B- [A (C)]-B C: vinylsilane monomer unit And, at the peak of the methine group of the vinyl ether monomer unit, Among them, the peak of 1) and the one of the above is around 3.5 ppm, and the peak of the one of 2) of the above sequence is around 3.8 ppm.
In addition, a peak of 3) in the above sequence occurs in the vicinity of 4.0 ppm, and a peak of 4) in the sequence above occurs in the vicinity of 4.4 ppm.

In the peak of the methine group of the vinylsilane monomer unit, the peak of 1) in the above sequence is near 0.7 ppm, and the peak of 2) in the above sequence is also around 0.7 ppm. At around 1.0 ppm, the peak of 3) in the sequence is present at around 1.2 ppm, and the peak of some of sequence 4) is at around 1.6 ppm.

In the copolymer of the present invention, the total integrated value of the peaks of the respective methine groups of the vinyl ether monomer unit and the vinylsilane monomer unit and the peak of the methylene group of the fluorine-containing vinyl ether monomer unit. It is possible to know the content of each monomer unit by relatively comparing the total integrated values of.

The number average molecular weight of the fluorine-containing vinyl ether copolymer of the present invention is in the range of 2,000 to 200,000. Further, the range of 5,000 to 100,000 is preferable in terms of practicality. Number average molecular weight is 2,
A copolymer having a molecular weight of less than 000 has a relatively large number of terminal groups, so that the effects such as water repellency are reduced and the original function is not exhibited. Further, a copolymer having a number average molecular weight of more than 200,000 is not preferable because its solubility in a general organic solvent is poor and the method of use is limited.

The fluorine-containing vinyl ether copolymer of the present invention can be produced by the following method.

That is, the general formula (4)

[0048]

Embedded image

(Wherein R is an alkyl group) 20 to 60 mol% of a vinyl ether monomer represented by the general formula (5)

[0050]

[Chemical 19]

(However, R _f is a perfluoroalkyl group, or

[0052]

Embedded image

(However, p is an integer of 0 or more.). ) Fluorine-containing vinyl ether monomer 30)
70 mol%, and further, the general formula (6)

[0054]

[Chemical 21]

(Wherein X ¹ , X ² and X ³ are the same or different, and at least one is a group capable of being hydrolyzed to form a hydroxyl group). It is a method of copolymerizing with mol%.

As the vinyl ether monomer used in the present invention, known compounds can be used without any limitation as long as they satisfy the general formula (4). Specific examples are methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, cyclohexyl vinyl ether, 2-ethylhexyl vinyl ether and n-octyl vinyl ether. The effects of the present invention can be achieved even if these vinyl ether monomers are used alone or as a mixture of two or more kinds.

Next, the fluorine-containing vinyl ether used in the present invention is a compound represented by the above general formula (5). This fluorine-containing vinyl ether has good copolymerizability with the above-mentioned vinyl ether monomer and vinylsilane monomer. This is an ether-bonded group of fluorine-containing vinyl ether, that is, a perfluoroalkyl group or

[0058]

[Chemical formula 22]

It is considered that the carbon atom bonded to is replaced by a hydrogen atom and the electron density of the double bond is increased, so that the polymerizability is improved.

In the above fluorine-containing vinyl ether,
The carbon number of R _f is not particularly limited, but in consideration of the effect and cost, it is preferably a perfluoroalkyl group having 1 to 12 carbon atoms, and specifically, —CF ₃ , —CF ₂ CF.
_{3, -CF 2 CF 2 CF 3} , -CF 2 (CF 2 CF 2) q CF 3
(Q = 1~4), - CF (CF 3) {OCF 2 CF (CF
₃ )} _r OCF ₂ CF ₂ CF ₃ (r = 0 to 2) and the like.

These fluorine-containing vinyl ethers can be easily obtained by reacting the corresponding alkali metal salt of fluorine-containing alcohol with tetrafluoroethylene. Below, those are illustrated.

[0062]

[Chemical formula 23]

Next, as the vinyl silane monomer used in the present invention, known compounds can be used without any limitation as long as they satisfy the general formula (6). Specific examples include alkoxyvinylsilane such as trimethoxyvinylsilane, triethoxyvinylsilane, ethoxydimethylvinylsilane, and ethyldimethoxyvinylsilane; hydrolyzable groups such as halogenated vinylsilane such as chlorodimethylvinylsilane, dichloromethylvinylsilane, and bromodiethylvinylsilane. Is to have. The effects of the present invention can be achieved even if these vinylsilane monomers are used alone or as a mixture of two or more kinds.

In the present invention, the composition of the vinyl ether monomer, the fluorine-containing vinyl ether, and the vinyl silane monomer is (4): 20 to 60 mol%, (5):
Copolymerization is carried out at 30 to 70 mol% and (6): 1 to 25 mol%. For example, bulk polymerization, solution polymerization and the like. As the polymerization initiator used for the polymerization, known compounds can be used. For example, diacyl peroxides such as octanoyl peroxide and lauroyl peroxide;
Peroxydicarbonates such as diisopropylperoxydicarbonate and dipropylperoxydicarbonate; peroxyesters such as butylperoxyacetate and butylperoxypivalate; azo peroxides such as azobisbutyronitrile Moreover, perfluorobutyl peroxide and the like are used as the fluorine-based peroxide. One or more of these polymerization initiators may be used.

When solution polymerization is carried out, the solvent used may be any one which does not inhibit the polymerization and can dissolve the monomers used. For example, use aliphatic hydrocarbons such as hexane and heptane; aromatic hydrocarbons such as benzene and toluene; halogen-based solvents such as methylene chloride, carbon tetrachloride, and 1,1,2-trichlorotrifluoroethane. You can

The polymerization temperature depends on the decomposition temperature of the polymerization initiator, but the polymerization can usually proceed at 10 to 100 ° C.

If necessary, a chain transfer agent such as mercaptan can be used for controlling the molecular weight.

The fluorine-containing vinyl ether copolymer of the present invention is

[0069]

[Chemical formula 24]

A silanol group can be generated due to the group contained in the vinylsilane monomer unit represented by and capable of being hydrolyzed into a hydroxyl group. Since the silanol groups are condensed and crosslinked, such a fluorine-containing vinyl ether copolymer has the ability to cure and form a strong coating film. Such curing can be easily caused by exposing the copolymer to an atmosphere in the presence of water such as air. Usually, it is suitable to carry out by drying the organic solvent after applying the organic solution of the copolymer. The temperature is not particularly limited, and room temperature is sufficient. The organic solvent is usually used in the field of paints, and may be any one as long as it can dissolve the fluoropolymer, for example, aromatic hydrocarbons such as benzene, toluene, xylene, acetone, methyl ethyl ketone, etc. , Ketones such as diethyl ether, dipropyl ether, tetrahydrofuran and the like, halogenated hydrocarbons such as dichloroethane, chlorobenzene, and 1,1,2-trichlorotrifluoroethane can be used without limitation. Dissolved concentration of copolymer is 5 ~ 60wt%
Is common. In addition, a silanol curing catalyst may be added as necessary to accelerate the curing rate. Here, a known silanol curing catalyst can be used. For example,
Carboxylic acid metal salts such as dibutyltin dilaurate, stannous acetate, stannous octoate, lead naphthenate, iron 2-ethylhexanoate; organic bases such as ethylamine, hexylamine, dibutylamine, piperidine, mineral acids, organic fatty acids, etc. Can be used. The blending amount of these silanol condensation catalysts is not particularly limited, but is preferably 0.01 to 5 wt% with respect to the polymer weight.

[0071]

Since the fluorine-containing vinyl ether copolymer of the present invention has a specific fluorine-containing vinyl ether monomer unit, it has weather resistance and water repellency as compared with resins obtained from ordinary vinyl ether monomers. Excellent oil repellency. Further, since it also has a vinylsilane monomer having a group capable of being hydrolyzed to a hydroxyl group, it cures in air and exhibits excellent chemical resistance and solvent resistance. Therefore, such a copolymer can be used as a paint or a surface coating agent, especially in a field where weather resistance and chemical resistance are problems.

[0072]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. The analysis and physical properties of the copolymer obtained in the present invention were measured by the following methods.

(1) Measurement of molecular weight 0.01 g of the obtained copolymer was added to tetrahydrofuran 10
It was dissolved in ml and the molecular weight was measured by gel permeation chromatography (GPC) with reference to standard polystyrene.

(2) Measurement of contact angle The contact angle was measured by using a contact angle measuring machine using water and n-hexadecane.

(3) Adhesion test According to JIS K 5400-1990 General paint test method 8.5.1 Cross-cut test, glass and aluminum were used as the base materials for measurement.

(4) Acetone Immersion Test The material coated on the substrate was immersed in acetone for 24 hours to examine the change in the surface of the coating film.

Example 1 In a four-necked flask having an internal volume of 200 cc and being purged with nitrogen,
Oxygen-removed fluorine-containing vinyl ether (R _f = C ₂ F ₅ ; hereinafter referred to as FVE) 36.8 g, n-butyl vinyl ether (hereinafter referred to as B)
12.8 g of VE), 4.7 g of trimethoxyvinylsilane (hereinafter referred to as TMOVS), and 0.26 g of azobisisobutyronitrile were charged, and they were polymerized at 60 ° C. for 8 hours. Next, the reactor was cooled, the reaction was stopped, the contents were dissolved in tetrahydrofuran, precipitated in a large amount of methanol, and dried. Polymer yield is 5
The polymerization rate was 80% at 4.5 g.

The purified polymer was measured by ¹ H-NMR (see FIG. 1) in a deuterated chloroform solvent.
A spectrum based on CH ₂ (4.2 ppm) of OCH ₂ CF ₂ CF ₃ was observed. Further, proton peaks derived from the methine group of the BVE unit were observed at 3.8, 4.0 and 4.4 ppm. In addition, the peak of the proton derived from the methine group of the TMOVS unit overlapped with the signal of BVE, so only the 0.7 ppm signal could be directly observed, but the signal of other protons derived from the BVE monomer was observed. Considering the integrated value calculated from, TMOVS at 1.0, 1.2, and 1.6 ppm
It was confirmed that the respective peaks derived from the methine group of were present. From this result, it was found that each monomer unit was randomly arranged. From this, the calculated fluorine-containing vinyl ether monomer unit content was 46.7 mol% and the n-butyl vinyl ether monomer unit content was 45.7 mol%.
Met. The number average molecular weight Mn of this polymer is 33,20.
And the weight average molecular weight Mw was 69,000. Next, the polymer obtained by the polymerization was mixed with tetrahydrofuran: xylene = 4: 1 (v / v) to obtain a mixed solution of about 10 wt.
% Of the solution was applied to each of the base materials and allowed to stand at room temperature in a humidity of 70% for 1 day, and then a coating film test was conducted. The results are shown in Tables 1 and 2.

Example 2 In a stainless steel autoclave with a stirrer having an internal volume of 300 cc, 1,1,2-trichlorotrifluoroethane 50.
0 g, FVE51.8 g, propyl vinyl ether 1
5.5 g (PVE), triethoxyvinylsilane (TE
OVS) 8.6 g, azobisisobutyronitrile 0.3
Charge 7 g, repeat solidification and degassing with liquid oxygen,
Oxygen in the system is removed. Then, it was polymerized at 60 ° C. for 8 hours. The reactor was then cooled, the reaction was stopped and the unreacted monomer and solvent were removed under reduced pressure. Next, the content was dissolved in tetrahydrofuran, precipitated in a large amount of methanol, and dried. The polymer yield was 58.7 g and the polymerization rate was 77%.

When the ¹ H-NMR of the purified polymer was measured in a deuterated chloroform solvent, OCH ₂ CF ₂
A spectrum based on CH ₂ (4.2 ppm) of CF ₃ was observed. In addition, proton peaks derived from the methine group of the PVE unit were observed at 3.8, 4.0 and 4.4 ppm. Further, the peak of the proton derived from the methine group of the TEOVS unit overlaps with the signal of PVE, so only the 0.7 ppm signal is directly observed, but it is calculated from the signals of other protons derived from the PVE monomer. Considering the integrated values of 1.0, 1.2,
It was confirmed that each peak derived from the methine group of TEOVS was present at 1 and 1.6 ppm. From this result, it was found that each monomer unit was randomly arranged. From this, the calculated fluorine-containing vinyl ether monomer unit content was 51.2 mol% and the propyl vinyl ether monomer unit content was 45.3 mol%. The number average molecular weight Mn of this polymer was 32,100, and the weight average molecular weight Mw was 67,000. Next, the polymer obtained by the polymerization was treated with tetrahydrofuran: xylene = 4: 1 (v
/ V) adjusted to about 10 wt% with a mixed solution, and 0.1 wt% of dibutyltin dilaurate as a silanol curing catalyst to the polymer weight was added to each of the solutions, and the solution was applied to a substrate at a humidity of 70% at room temperature. After being left in a wet state for 1 day, a coating film test was conducted. The results are shown in Tables 1 and 2.

Examples 3 to 13 Copolymerization was carried out in the same manner as in Example 1 except that various fluorine-containing vinyl ether monomer units, vinyl ether monomers and vinylsilane monomers were used and the composition shown in Table 1 was used. The polymerization rate, ¹ H-NMR measurement result, and coating film test result are shown in Tables 1 and 2. In addition, in the ¹ H-NMR measurement of each produced fluorine-containing vinyl ether copolymer, the signals were not directly observed because of duplication, but 1.0, 1.
It was confirmed that proton peaks derived from the methine group of the vinylsilane monomer unit also existed at 2 and 1.6 ppm.

Comparative Example In an autoclave with a stirrer made of stainless steel and having an internal volume of 300 cc, 50.0% of 1,1,2-trichlorotrifluoroethane was added.
g, butyl vinyl ether (BVE) 24.0 g, trimethoxy vinyl silane (TMOVS) 8.9 g, and azobisisobutyronitrile 0.5 g were charged, and solidification and deaeration with liquid oxygen were repeated to remove oxygen in the system. To do. Thereafter, 30.0 g of tetrafluoroethylene (TFE) is introduced into the autoclave and the temperature is raised. 8 at 60 ℃
Polymerized for hours. Then cool the reactor, stop the reaction,
Unreacted monomer was expelled. After that, the autoclave was opened, the contents were concentrated, dissolved in tetrahydrofuran, precipitated in a large amount of methanol, and dried. The polymer yield was 91.9 g and the polymerization rate was 81%.

The purified polymer was found to have a fluorine-containing vinyl ether monomer unit content of 52.3 mol% calculated from the results of ¹ H-NMR and ¹⁹ F-NMR measurements in a deuterated chloroform solvent, and contained n-butyl vinyl ether. The content of monomer units was 41.7 mol%. The number average molecular weight Mn of this polymer is 12,000, and the weight average molecular weight M
w was 25,000. Next, the polymer obtained by the polymerization was treated with tetrahydrofuran: xylene = 4: 1 (v /
v) The mixed solution was adjusted to about 10 wt%, and a solution containing 0.1 wt% of dibutyltin dilaurate as a silanol curing catalyst added to the weight of the polymer was applied to each base material, and the humidity was kept constant at room temperature and 70% humidity. After leaving it in the state for one day,
A coating film test was conducted. The results are shown in Tables 1 and 2.

[0084]

[Table 1]

[0085]

[Table 2]

[0086]

[Table 3]

[Brief description of drawings]

FIG. 1 is a proton nuclear magnetic resonance spectrum chart of the fluorine-containing vinyl ether copolymer of the present invention obtained in Example 1.

FIG. 2 is a diagram showing the content of each monomer unit constituting the fluorine-containing vinyl ether copolymer of the present invention.

Claims (1)

[Claims] 1. A general formula (1): (However, R is an alkyl group.) 20 to 60 mol% of a vinyl ether monomer unit represented by the general formula (2): (However, R _f is a perfluoroalkyl group, or (However, p is an integer of 0 or more.). 30 to 70 mol% of a fluorine-containing vinyl ether monomer unit represented by the formula (3) and a compound represented by the general formula (3): (However, X ¹ , X ² , and X ³ are the same or different,
At least one is a group that can be hydrolyzed to a hydroxyl group. The vinylsilane monomer unit represented by 1) is randomly arranged with 1 to 25 mol% and has a number average molecular weight of 2,000.
A fluorine-containing vinyl ether copolymer, which is 0 to 200,000.