JPS61148203A - Polyvinyl alcohol based polymer having fluorine-containing group - Google Patents

Abstract

PURPOSE:A novel polyvinyl alcohol based polymer, containing a specific fluorine- containing monomer units, having improved water and oil repellency and specific dissolving characteristics originating from the association between the fluorine- containing groups, and useful as a surface treating agent, etc. CONSTITUTION:A polymer, obtained by copolymerizing a fluorine-containing monomer with a vinyl ester, e.g. vinyl acetate, and saponifying the resultant copolymer, and containing preferable 0.02-5mol% one or more of fluorine- containing monomer units expressed by formulas I-VII (R<1>-R<4> are H, 1-20C alkyl, allyl or aralkyl; M is alkali metal salt or ammonium salt group; Rf is fluorine-containing group; X is linking group; m is 0 or 1).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyvinyl alcohol (hereinafter polyvinyl alcohol may be abbreviated as PVA) polymer having a fluorine-containing group. More specifically, the following general formula (I
PVA containing at least one type of fluorine-containing monomer unit represented by ) to (■), having excellent water repellency and oil repellency, and having unique solution properties derived from the association between fluorine-containing groups
Related to polymers.

Conventional Technology As is well known, fluorocarbon surfaces have extremely low surface energy, and have surface chemical characteristics such as being ``resistant to wet'', ``resistant to staining'', and ``easy to slip'', as well as being heat resistant and resistant. Excellent chemical properties. Recently, surface processing technology using fluorocarbons that takes advantage of these properties has progressed and is being applied in various fields.

In addition, so-called fluorine-based surfactants have attracted much attention because they have excellent interfacial properties in a variety of ways compared to conventional hydrocarbon-based surfactants, and are effective even in small amounts.

Problems to be Solved by the Invention However, on the other hand, fluorocarbon compounds are generally extremely expensive, so it is necessary to develop a field that utilizes only the surface properties formed by fluorocarbons, except when utilizing the bulk properties of fluorocarbons. There is expected. A typical example is fluorine-based antifouling treatment, which imparts water and oil repellency to fibers. However, when used in combination with other materials, especially when adhesion is required, the characteristics of the fluorocarbon surface can be a hindrance, and new technical solutions are needed.

Means for Solving the Problems Under these circumstances, the present inventors investigated the modification of Pv'A polymers with fluorine-containing groups, and as a result, completed the present invention.

The present invention has a major feature in -6~ containing at least one fluorine-containing monomer unit represented by the following general formulas (I) to (VII).

(1) +CH2-CR÷ "CH2 0-(X demand Rf (■) (-CH2-CR+ 0-(X)ilii-Rf (III) (-CH2-CR± C=0 0M) The type of fluorine-containing group Rf in each formula (1) to (VI+) greatly influences the properties of the PVA polymer obtained. In order to express s Rf, for example, R
(-CF2+- (R represents F or H),
It is essential that n is 2 or more, and the larger the n, the greater the effect, but if n exceeds 20, the solubility in the polymerization system during production will decrease and the solubility of the resulting PVA polymer will decrease. Therefore, it is preferable that n is in the range of 2 to 20. Also, when Rf contains atoms such as oxygen, nitrogen, sulfur, etc., the same thing can be said as in the case of R(-CFz+n).
2-20), H-(-CF2-)-(n = 2-2
0 ), (CF3-)-CF-(-CF2CF2(n
-0 to 20), (CFa-)-C1F((-CFz-
)−(n=O~20), 2
n F-(-CF2CF2-09 (n = 1 to 10),
Examples include F(-CFCFa-CF20U1 (n = 1 to 10) 0 In addition, X in each of the above formulas (I) to (■) is a link between the PVA polymer main chain and the fluorine-containing group Rf. As a group, acetic acid, alkyl group,
It represents an alkyl ether group, an alkylthioether group, etc., but is not particularly necessary.

91 The PVA-based polymer of the present invention can also be produced by a so-called polymer reaction of a PVA-based polymer, but it can also be produced by a so-called polymer reaction of a PVA-based polymer, but it can also be produced by using vinyl esters such as e-vinyl acetate and corresponding to each of the above formulas (I) to (VII). It is industrially advantageous to produce it by copolymerizing and saponifying monomers.

In this case, if the Rf group is bonded by a group that is cleaved by a saponification reaction, such as an ester group, the PVA-based polymer having a fluorine-containing group of the present invention cannot be obtained. For this reason, it is necessary that X be a stable bond under the conditions in which the saponification reaction is carried out.

Furthermore, the general formula (I) which occupies in the PVA-based polymer of the present invention
The content of the fluorine-containing cumulative monomer units represented by (VII) is set to 0.00000000000000000000000000000000000000000000000000000000000000000 type type type type type type type type type form type type form type type form type form type form nature condition form.
It is preferably in the range of 0.01 to 10 mol. L<, o, and more preferably in the range of 0.02 to 5 mol.

Furthermore, there is no particular restriction on the degree of polymerization or the distribution of degree of polymerization of the PVA polymer having a fluorine-containing group of the present invention, but the degree of polymerization is 2.
00 or more, preferably 300 or more, and 10,000 or less because of excellent strength performance.

The saponification degree is 50 molti or more, preferably 70 molti or more.

Furthermore, the PVA-based polymer having a fluorine-containing group of the present invention may contain at least one of the fluorine-containing monomer units represented by the above general formulas (I) to (VII), and may contain other monomers. There is no problem in containing monomer units such as ethylene, carboxylic acid or its salt, sulfonic acid or its salt, amine, amide, and the like.

The PVA-based polymer containing at least one type of fluorine-containing monomer unit represented by the general formulas (I) to (VII) of the present invention is one of the following compounds corresponding to the formulas (■) to (■). (■)′～(
(2) It is produced by copolymerizing a fluorine-containing monomer represented by formula 7 with a vinyl ester such as vinyl acetate, and saponifying the copolymer.

(I)lCH2=CR" ♂H2 0-(X), Rf (old'CH2=CR" O-(X), Rf (1!I)'C1■2=CR' C=:O General formula above Specific examples of fluorine-containing monomers represented by (I)' to (■)' include CH2=CHCl'I
20CH2+CFz+-H.

CH2=CHCH+0CH2, (-CF2'+-H%C
Mountain=CHCH20CH2-(もF2toH,・CH2=C
HCH20CH2I CF2 introduction H1C Le = C appears ■ Coffee 1 ÷
σ2~F1CH2=CHCH20C1(2CHz, (-
CF2F, CH2=CH0CH2-(-CF2)H
1CH2-CHDCH2%CF2+-H, CH2=CM
)CH2-fcF2-)-H1CH2flatCHOCH2-
(-CF2+-H, CH2壬cHOc part l÷CF2←F
1CH2=CH0CI(2CH2+CF2)-F, O
H,1=CHCON(CH3)CHz%CF2')-F
.

CH2=CHCON(CzHs)CHHPF6F, C
E(2=cHcON(C4HJI)CHHPF6-F1
CHz=CHCON(CHa)CH2+cFz+-F,
CH3=C(C3F7)COOCH3, CH2=C(
C3F7)CN, CH2=C(C7F15)CN,
CH2=C(C9F19)CN.

CH2=C(C3F7)CONH2, CHz=C(C7
F1s) COONa and the like.

All of the monomers represented by the above general formulas (I)' to (■)' are stable to alkalis, and when producing fiPVA-based polymers by saponifying polyvinyl ester-based polymers, they are The ether bond or amide bond to which the fluorine group is bonded is not cleaved, and the PVA-based composite having the fluorine-containing group of the present invention is obtained.

The polymerization method for obtaining the PVA-based polymer of the present invention is generally known, such as bulk polymerization, solution polymerization, suspension polymerization,
Although any method such as emulsion polymerization may be employed, solution polymerization using methanol, toluene, etc. is most preferred industrially. Further, as a polymerization process, production can be performed by any of batch, semi-batch, and continuous processes. Further, the initiator used is usually a known radical polymerization initiator. For example, 2,2'-azobisinbutyronitrile, 2,2'-azobis(4-methoxy-2,
(4-dimethylvaleronitrile), benzoyl peroxide, diimpropyl peroxydicarbonate, potassium persulfate, and the like. The polymerization temperature can be appropriately set depending on the initiator used, but is preferably 10 to 90°C.

Examples of the vinyl ester used in the present invention include vinyl acetate, vinyl formate, vinyl propionate, vinyl persate (Veova 10, a product of Shell Co., Ltd.), vinyl laurate, and the like. P
In order to obtain a VA polymer, it is preferable to use vinyl acetate as a main component.

Furthermore, in the polymerization of the present invention, there is no problem in copolymerizing monomers that can be copolymerized with the above-mentioned vinyl esters. These monomers include olefins such as ethylene, propylene, and imbutylene, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Acrylic acid esters such as lauryl acrylate, methacrylic acid esters such as methacrylic acid or methyl methacrylate, butyl methacrylate, lauryl methacrylate, dimethylamine ethyl methacrylate, methacrylic acid (2-hydroxyethyl), vinyl chloride, chloride vinylidene,
710 vinylides such as vinyl fluoride, vinylidene fluoride, and tetrafluoroethylene, acrylamide, methacrylamide, 2-acrylamido-2-methylpropanesulfonic acid or its salts, acrylamide derivatives such as dimethylacrylamide, acrylonitrile, methacrylic acid + -Vinyl ethers such as IJ, methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, lauryl vinyl ether, maleic acid derivatives such as maleic anhydride, monoethyl maleate, maleic acid, itaconic acid, fumaric acid and These monoesters and diesters can be mentioned.

In order to obtain a PVA polymer by saponifying the polyvinyl ester polymer having a fluorine-containing group of the present invention, generally known methods such as alkali saponification and acid saponification can be employed, but industrially methanol solvent And NaOH-?
Methanolysis catalyzed by CHaONa is most advantageous. There is no particular restriction on the saponification temperature, but the obtained P
Coloring of VA polymers 1 20-6 from the viewpoint of prevention
Preferably, it is carried out at 0°C. In addition, the amount of NaOH or CHaONa used as a catalyst is 1 mol/l of vinyl ester unit.
It is preferable that the amount is in the range of 0.001 to 0.2 mol from the viewpoint of preventing coloration of the resulting PVA polymer and suppressing the amount of acetic acid. When a copolymer unit that consumes alkali, such as an acid, is used, it is necessary to add the amount within the above range and to perform saponification accordingly.

The PVA-based polymer of the present invention can be applied to various uses due to its excellent properties. For example, it can be applied to the surface treatment of paper and fibers, and when applied to vinylon yarn, it provides a surface with a low stiffness coefficient, and a new vinylon yarn that does not require the use of an oiling agent or is effective with the use of a very small amount can be obtained. Furthermore, the aqueous solution exhibits extremely low surface tension and can be used as a new fluorine-based surfactant.

Function and Effects of the Invention The PVA polymer having a fluorine-containing group of the present invention has two main characteristics. One is that the surface of a molded product such as a film obtained from an aqueous solution has excellent oil and water repellency.

PVA-based polymer films usually have a large surface energy, so they do not have so-called oil repellency, and because they are originally water-soluble, they also have insufficient water repellency. On the other hand, the surface of a molded article made from a PVA polymer having a fluorine-containing group according to the present invention has significantly excellent oil repellency and water repellency, reflecting the properties of the fluorine-containing group.

Another feature is seen in the solution properties. That is, phenomena such as an increase in solution viscosity and further gelation due to association between fluorine-containing groups. A similar phenomenon is also observed in the case of PVA-based polymers having long hydrocarbon chains instead of fluorine-containing groups, but the oil repellency is exhibited by the fluorine-containing PVA of the present invention.
These are properties unique to polymers, such as high solution viscosity and gelation depending on conditions, which can be achieved by introducing a small amount of fluorine-containing groups.Examples are shown below. The present invention will be specifically explained by citing the following, but the present invention is not limited to these.

In the following, unless otherwise specified, parts and parts refer to parts by weight and percent by weight.

Example 1 240 parts of vinyl acetate (hereinafter abbreviated as VAc), 50 parts of methanol, and fluorine-containing monomer [CH2=CH-CH2O-CL++CF2+-H] 3
．． 95 parts were placed in a reactor, the inside was sufficiently purged with nitrogen, the temperature was raised, and when the internal temperature reached 60°C, 10 parts of a methanol solution containing 0.0434 parts of 2,2'-azobisinbutyronitrile was added. and polymerization was started. Polymerization was carried out under stirring for 5 hours, and the polymerization rate was 55.6%. After cooling, the remaining VAc was expelled from the system together with methanol under reduced pressure while adding methanol to obtain a methanol solution of the copolymer. (Concentration 40.2%) Next, a part of this methanol solution was added to p[NaOH]/(VAc, :l
= 0.02 (% Le ratio).
A methanol solution was added and saponified at 40°C to obtain a polyvinyl alcohol (hereinafter abbreviated as PVA) copolymer. The degree of saponification is 98.7%, and the viscosity of 4% DMSO solution is 20
It was 130 Cp at ℃. Further, the fluorine-containing monomer content calculated by elemental analysis of F was determined to be 0.29 mol.

Example 2.3 Polymerization was carried out in the same manner as in Example 1, using different amounts of fluorine-containing monomers such as citron, and saponification to obtain a PVA-based copolymer. All the results are shown in Table 1.

□ Example 4 240 parts of vinyl acetate, 50 parts of methanol and fluorine-containing monomer [CH2=CH-0-CH2-(-CF2SF)
Pour 11.9 parts into a reaction vessel, and after thoroughly purging the inside with nitrogen, raise the temperature, and when the internal temperature reaches 60°C, 2.2 parts.
10 parts of a methanol solution containing 0.0434 parts of '-azobisinbutyronitrile was added to initiate polymerization. Polymerization was carried out under stirring for 7 hours, and the polymerization rate was 34.2%.

After cooling, the VAc remaining under reduced pressure was expelled from the system together with methanol while adding methanol.
A methanol solution of the combination was obtained. (concentration 35%) Next, take a part of this methanol solution and add [NaOH,
]/[VAc] = 0.0070 (mole ratio), a methanol solution of NaOH was added, and the mixture was saponified at 40°C to obtain a PVA copolymer. The degree of saponification is 84.5 molt, and the viscosity of 4% DMSO solution is 7° cp at 20°C.
Met. The fluorine-containing monomer content calculated from elemental analysis of F was 0.90 mol.

Example 5 A PVA-based copolymer was obtained by combining and saponifying M in the same manner as in Example 4 while changing the type and amount of the fluorine-containing monomer. The results are summarized in Table 2.

Table 2 Example 6 240 parts of vinyl acetate, 50 parts of methanol and fluorine-containing monomer [CH2= CHCON(CHa )CH2-(
-CF 2-J-7F) 26.1 parts into a reaction vessel,
After sufficiently purging the inside with nitrogen, the temperature was raised, and when the internal temperature reached 60°C, 10 parts of a methanol solution containing 0.0434 parts of 2,2'-azobisisobutyronitrile was added to initiate polymerization. . Polymerization was carried out under stirring for 2 hours, and the polymerization rate was 11.
．． It was 5%. After cooling, the remaining VAc was forced out of the system together with methanol under reduced pressure while adding methanol to obtain a methanol solution of the copolymer.

(concentration 42%) Next, a part of this methanol bath solution was
]/[VAC) = 0.02 (mole ratio). A methanol solution of NaOH was added, and the mixture was hydrogenated at 40'C to obtain a PVA-based copolymer (1). Saponification degree is 985
The viscosity of the DMSO solution is 78 at 20°C.
It was Cp. The fluorine-containing monomer content was calculated from elemental analysis of F to be 2.50 mol.

Example 7.8.9 A PVA copolymer was obtained by polymerizing and saponifying the fluorine-containing monomer using the same method as in Example 6 and 1iWJ while changing the type and conditions of the fluorine-containing monomer. The results are shown in Table 3.

Table 3 Next, regarding the effects of the fluorine-containing groups introduced by copolymerization for the PVA polymers obtained in Examples 1.2.3.8 and 9, PVA]]7 (■ manufactured by Kuraray, polymerization degree 170
0, saponification degree of 985 mol%). The test items and test methods are as follows, and the results are summarized in Table 4.

(1) Surface tension of aqueous solution 0.2 A water bath solution was prepared and measured at 20° C. using a Du Noulli type surface tension meter.

(2) Water repellency on the film surface A 3% aqueous solution was cast onto a PET film, air-dried at room temperature, and a 0.2 part thick film layer (4+) was coated.
After heat treatment at 60° C. for 10 minutes, water droplets were dropped on the air side of the film and the contact angle was measured.

(3) Oil repellency on the film surface Using the same film as made in (2), toluene droplets were dropped on the air side, and the state of "wetness" was observed and expressed as follows.

Items that cannot be wetted by toluene as droplets: 1 Items that can be partially wetted by toluene: 2 Items that can be completely wetted by toluene: 3 (4) Gelation 5% water bath solution for PVA that is soluble in boiled water Adjust 2
The state of gelation was observed by standing at 0°C.

What turned into gel:○ Things that don't gel: × Table 4

Claims (1)

[Scope of Claims] A polyvinyl alcohol polymer characterized by containing at least one type of fluorine-containing monomer unit represented by the following general formulas (I) to (VII). (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (III) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (IV) ▲ There are mathematical formulas, chemical formulas, tables, etc. Yes ▼ (V) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (VI) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (VII) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ However, R^1, R^2 , R^3 and R^4 represent H or an alkyl group having 1 to 20 carbon atoms, an allyl group, or an aralkyl group. M represents an alkali metal salt or an ammonium base. R_f represents a fluorine-containing group. X represents a linking group. m represents 0 or 1.