JP2001139750A - Water-resistant composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a water-resistant composition remarkably excellent not only in cold water, but also in warm water and hot water, without problems such as viscosity stability and without any problems about safety when dried or heat-treated at <=70 deg.C particularly at about room temperature to 50 deg.C, further relatively lower temperature such as room temperature after forming a film or applying to a substrate. SOLUTION: This water-resistant composition comprises a homogeneous mixture of (A) a vinyl alcohol-based polymer having 1-20 mol% <=4C α-olefin unit or a vinyl alcohol-based polymer having 1-20 mol% <=4C α-olefin unit and 0.01-1 mol% silyl group with (B) an organic titanium compound having chelate type ligand. In the composition, weight compounding ratio (A/B) of the component A to the component B is (99.99/0.01) to (60/4).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition having excellent water resistance comprising a specific modified vinyl alcohol-based polymer and an organic titanium compound having a chelate type ligand.

[0002]

2. Description of the Related Art Conventionally, vinyl alcohol-based polymers (hereinafter, vinyl alcohol-based polymers may be abbreviated as PVA) have been widely used as various kinds of binders, adhesives or surface treatment agents. Is known to have excellent performance unmatched by other water-soluble resins. However, because PVA is water-soluble,
There is a drawback that the water resistance, particularly when dried at a low temperature, is low, and various methods for improving this drawback have been conventionally studied. For example, a method is known in which PVA is crosslinked with glyoxal, glutaraldehyde or dialdehyde starch, a water-soluble epoxy compound, a methylol compound, or the like. However, in order to make PVA sufficiently water-resistant by this method, it is necessary to perform heat treatment at a high temperature of 100 ° C. or more, particularly 120 ° C. or more for a long time. It is also known to use strongly acidic conditions such as pH 2 or less in order to make water resistant by drying at low temperature, but in this case, the viscosity stability of the PVA aqueous solution is poor and gelation occurs during use. In addition to having problems, it has a drawback that water resistance is insufficient. In addition, there is a problem that the use of such severe conditions causes the PVA to be colored, thereby impairing the appearance of the film. Further, a method of crosslinking carboxyl group-containing PVA with a polyamide epichlorohydrin resin and a method of crosslinking acetoacetyl group-containing PVA with a polyhydric aldehyde compound such as glyoxal are also known. Requires a large amount of polyamide epichlorohydrin, and the latter has problems such as extremely low water stability but extremely poor viscosity stability of the PVA aqueous solution. Use of polyamide epichlorohydrin or polyhydric aldehyde is not preferable from the viewpoint of safety.

[0003] A method of imparting water resistance by blending titanium lactate with an aqueous composition containing PVA is also known (Japanese Patent Application Laid-Open No. 49-94768). When coated at a relatively low temperature around room temperature after coating, as described in Comparative Example 1 described later, sufficient water resistance cannot be imparted, such as collapse of a sheet in boiling water, and a PVA aqueous solution containing titanium lactate. Has a problem that the low temperature storage viscosity stability is poor.

It is also known to use a filler such as titanium oxide in combination with a modified PVA having an ethylene unit content of 3 to 15 mol% to obtain a heat-sensitive recording material by mixing alkali metal ions. (Kaihei 9-24016) and the use of titanium oxide in combination has extremely poor water resistance as described in Comparative Example 4 described later.

It is also known to obtain an adhesive by blending an inorganic filler such as titanium sulfate with a modified PVA having an ethylene unit content of 1 to 24 mol% (Japanese Patent Laid-Open No. 8-28).
3682), even when titanium sulfate is used in combination, the water resistance is extremely poor as described in Comparative Example 5 described later.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art. After the film is formed or after the substrate is coated, the temperature is 70 ° C. or less, particularly around room temperature to 50 ° C., and further around room temperature. Even when drying or heat treatment at a relatively low temperature, not only cold water but also warm water, hot water is remarkably excellent in water resistance, there is no problem such as viscosity stability, and there is no problem in terms of safety. An object is to provide a water-resistant composition.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to provide a modified P having 1 to 20 mol% of α-olefin units having 4 or less carbon atoms.
VA and an α-olefin unit having 4 or less carbon atoms are 1 to
At least one modified PVA selected from the group consisting of modified PVA having 20 mol% and 0.01 to 1 mol% of silyl group;
(A) and a homogeneous mixture of an organotitanium compound (B) having a chelate type ligand, wherein the component (A) and the component (B)
The weight ratio (A) / (B) of the components is 99.99 / 0.
This is achieved by providing a water resistant composition that is between 01 and 60/40.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION α in the water-resistant composition of the present invention
-Modified PVA having 1 to 20 mol% of olefin units
(A) is in the presence of an α-olefin (in the case of a gas at normal pressure, such as ethylene and propylene, under the pressure of such a gas)
In which the α-olefin-vinyl ester copolymer obtained by polymerizing the vinyl ester monomer is saponified. Vinyl ester monomers include vinyl formate, vinyl acetate, vinyl propionate,
Examples thereof include vinyl valerate, vinyl caproate, vinyl laurate, vinyl stearate, vinyl benzoate, vinyl pivalate, and vinyl versatate, with vinyl acetate being preferred. As a polymerization method of the vinyl ester monomer, a solution polymerization method, a bulk polymerization method,
Known polymerization methods such as a suspension polymerization method and an emulsion polymerization method are used, and usually, a solution polymerization method using an alcohol such as methanol as a solvent is used. The polymerization temperature is not particularly limited, but is usually arbitrarily selected between 0 ° C and 150 ° C.
As a method for saponifying a vinyl ester polymer, various known methods can be used. Usually, sodium alcoholate, sodium hydroxide, potassium hydroxide, or the like is used in an alcohol solvent (which may contain a small amount of water). A saponification method using an alkali is used.

The above modified PVA (A) can be converted to α-amino acid in the presence of a thiol compound such as thiolacetic acid, mercaptopropionic acid or an alkyl mercaptan having 18 or less carbon atoms.
A modified product having a mercapto group or a carboxyl group at the terminal obtained by copolymerizing an olefin and a vinyl ester monomer and saponifying it may be used.

It is important that the content of the α-olefin unit having 4 or less carbon atoms in the modified PVA (A) is 1 to 20 mol%, preferably 1.5 to 18 mol%, and more preferably 2 to 20 mol%.
-15 mol% is more preferable, and 2-13 mol% is the best. When the content of the α-olefin is lower than the lower limit or higher than the upper limit, the object of the present invention is not achieved as is apparent from Comparative Examples 11 and 12 described later.

Examples of the α-olefin having 4 or less carbon atoms include ethylene, propylene, 1-butene and isobutene, and ethylene is the best as apparent from the examples described later.

Next, in the present invention, the modified PVA (A) contains 1 to 20 mol% of an α-olefin unit having 4 or less carbon atoms.
And modified PVA having 0.01 to 1 mol% of silyl group
(A) is mentioned, but this modified PVA is the best modified PVA because the effect of the present invention is remarkably improved, as is clear from the examples described later.

The PVA (A) having an α-olefin unit having 4 or less carbon atoms and a silyl group can be obtained by various methods, but usually, in the synthesis of the modified PVA having the α-olefin unit described above. An olefinically unsaturated monomer having the following silyl group (I) during the copolymerization of an α-olefin having 4 or less carbon atoms with a vinyl ester, or having a group capable of forming a silyl group (I) after polymerization or saponification By saponifying the vinyl ester copolymer obtained by copolymerization with

As the silyl group, those represented by the following formula (I) are preferred.

[0015]

Embedded image

Wherein R1 represents a hydrogen atom or a hydrocarbon group which may have a substituent and has 8 or less carbon atoms, preferably an alkyl group, and R2 represents an alkoxyl group having 1 to 40 carbon atoms or Acyloxyl group (where alkoxyl group,
An acyloxyl group may have a substituent containing oxygen), n + m is 3 or less, n is an integer of 0 to 2, m
Represents an integer of 0 to 3, and X represents a monovalent metal. Monovalent metals include sodium and potassium, which are mainly introduced during saponification. ｝

The silyl group (I) has on the side chain or terminal of the modified PVA (A), and the silyl group (I) and the PVA
A linking group that is not cleaved during saponification may be interposed between the side chains or the terminals of (A).

Having a silyl group (I) or polymerizing,
Specific examples of the olefinically unsaturated monomer having a group capable of forming a silyl group (I) after saponification include, for example, vinyltrimethoxysilane, vinyltris- (β-methoxyethoxy) silane, allyltrimethoxysilane, and vinyltrimethoxysilane. Acetoxysilane, allyltriacetoxysilane, vinylmethyldimethoxysilane, vinyldimethylmethoxysilane, vinylmethyldiethoxysilane, vinyldimethylethoxysilane, vinylmethyldiacetoxysilane,
Vinyldimethylacetoxysilane, vinylisobutyldimethoxysilane, vinyltriisopropoxysilane, vinyltributoxysilane, vinyltrihexyloxysilane, vinylmethoxydihexyloxysilane, vinyldimethoxyoctyloxysilane, vinylmethoxydioctyloxysilane, vinyltrioctyl Roxysilane, vinylmethoxydilauroxysilane, vinyldimethoxylauryloxysilane, vinylmethoxydioleyloxysilane,
Vinyldimethoxyoleyloxysilane, 3- (meth) acrylamido-propyltrimethoxysilane, 3- (meth) acrylamido-propyltriethoxysilane, 3
-(Meth) acrylamide-propyltri (β-methoxyethoxy) silane, 2- (meth) acrylamide-2
-Methylpropyltrimethoxysilane, 2- (meth) acrylamide-2-methylethyltrimethoxysilane,
N- (2- (meth) acrylamido-ethyl) -aminopropyltrimethoxysilane, 3- (meth) acrylamido-propyltriacetoxysilane, 2- (meth) acrylamido-ethyltrimethoxysilane, 1- (meth) acrylamido- Methyltrimethoxysilane, 3-
(Meth) acrylamido-propylmethyldimethoxysilane, 3- (meth) acrylamido-propyldimethylmethoxysilane, 3- (N-methyl- (meth) acrylamido) -propyltrimethoxysilane, 3-((meth) acrylamido-methoxy) -3-Hydroxypropyltrimethoxysilane, 3-((meth) acrylamido-methoxy) -propyltrimethoxysilane, dimethyl-3- (meth) acrylamido-propyl-3-
Examples include (trimethoxysilyl) -propylammonium chloride, dimethyl-2- (meth) acrylamido-2-methylpropyl-3- (trimethoxysilyl) -propylammonium chloride, but are not limited thereto. The content of the silyl group is 0.01
It is important that the content is 0.1 to 1 mol%, preferably 0.1 to 1 mol%.
1 mol%. Further, in PVA (A) having an α-olefin unit having 4 or less carbon atoms and a silyl group, a preferable range of the α-olefin unit having 4 or less carbon atoms includes the α-olefin unit having 4 or less carbon atoms described above. PVA
This is the same as the preferred range of (A).

A vinyl alcohol polymer (A) having an α-olefin unit having 4 or less carbon atoms and a silyl group (I)
As other methods for obtaining the above-mentioned α-
In the synthesis of a vinyl alcohol polymer having an olefin unit, polymerization of an α-olefin and a vinyl ester is performed in the presence of a comonomer having an epoxy group such as allyl glycidyl ether or butadiene monoxide,
The resulting α-olefin-vinyl ester copolymer having an epoxy group, a compound having a mercapto group and a silyl group in the same molecule, such as trimethoxysilylmethyl mercaptan, and then saponified, followed by saponification to obtain a vinyl alcohol-based compound. Examples of the method include a method of forming a polymer. Also, α-
In the synthesis of a vinyl alcohol-based polymer having an olefin unit, a compound having a mercapto group and a silyl group in the same molecule, such as trimethoxysilylmethyl mercaptan, is used as a chain transfer agent for polymerization, and the obtained α-olefin is obtained. -A method of saponifying a vinyl ester polymer to obtain a vinyl alcohol polymer having an α-olefin unit and a silyl group (in this case, a terminally modified product), but is not limited to these methods. is not.

The degree of polymerization of the modified PVA (A) is not particularly limited, but is preferably from 50 to 10,000, more preferably from 100 to 7000, even more preferably from 150 to 5,000. 20
Most preferably, it is 0 to 4000. Here, the degree of polymerization is a value measured according to JIS K6726.
It is determined from the intrinsic viscosity measured in water at ° C.

The degree of saponification of the modified PVA (A) is not particularly limited, but is preferably 65 to 99.99 mol%, more preferably 80 to 99.8 mol%, and 90 to 90 mol%. More preferably, it is 99.7 mol%.

The modified PVA (A) may have one or two or more other monomer units as long as the purpose of the present invention is not impaired. Examples of such a unit include acrylic acids, methacrylic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride, unsaturated acids such as itaconic acid and salts thereof or having 1 to 1 carbon atoms.
18 mono or dialkyl esters; acrylamide, C 1-18 N-alkylacrylamide,
Acrylamides such as N, N-dimethylacrylamide, 2-acrylamidopropanesulfonic acid and salts thereof, acrylamidopropyldimethylamine or salts thereof or quaternary salts thereof; methacrylamide, having 1 carbon atom
Methacrylamides such as N-alkyl methacrylamide, N, N-dimethyl methacrylamide, 2-methacrylamidopropanesulfonic acid and salts thereof, methacrylamidopropyldimethylamine or acid salts or quaternary salts thereof; N-vinylamides such as vinylpyrrolidone, N-vinylformamide and N-vinylacetamide; vinyl cyanides such as acrylonitrile and methacrylonitrile; vinyl ethers such as alkyl vinyl ethers having 1 to 18 carbon atoms, hydroxyalkyl vinyl ethers and alkoxyalkyl vinyl ethers Classes: polyethylene glycol allyl ether, methoxy polyethylene glycol allyl ether, polypropylene glycol allyl ether, polyethylene glycol-polypropylene Allyl ethers having a poly (oxyalkylene) group such as recall allyl ether; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride and vinyl bromide; allyl acetate, allyl chloride, allyl alcohol; Examples include, but are not limited to, dimethylallyl alcohol. The content of these monomer units is not particularly limited, as long as the resulting polymer is water-soluble, but the content of these components is usually preferably 10 mol% or less.

In the present invention, among the above modified PVAs, PVA having 1 to 20 mol% of α-olefin units having 4 or less carbon atoms and 0.01 to 1 mol% of silyl groups is the best, PVA having 1 to 20 mol% of α-olefin units of 4 or less is preferred.

The organotitanium compound (B) having a chelate type ligand constituting the water-resistant composition of the present invention includes:
Titanium lactate, a partially or completely neutralized product thereof (for example, titanium lactate monoammonium salt, titanium lactate diammonium salt, titanium lactate monosodium salt, titanium lactate disodium salt, titanium lactate monopotassium salt, titanium lactate dipotassium salt), Diisopropoxy titanium bis (triethanol aminate), di-n-butoxy titanium bis (triethanol aminate), diisopropoxy titanium bis (acetyl acetonate), titanium tetrakis (acetyl acetonate), poly titanium bis (acetyl acetonate), etc. But are not limited to these. Among these organic titanium compounds, water-soluble ones are preferable,
Specific examples include titanium lactate, titanium lactate ammonium salt, diisopropoxytitanium bis (triethanol aminate), and di-n-butoxytitanium bis (triethanol aminate). These organic titanium compounds do not necessarily have to be used alone, and may be used as a mixture of two or more as necessary.

Here, the chelate type ligand is 1
A ligand capable of coordinating bidentate or multidentate by covalent bond or hydrogen bond to two titanium atoms, such as hydroxycarboxylic acid or its salt (lactic acid, Representative examples include, but are not limited to, malic acid, tartaric acid, salicylic acid and salts thereof), β-diketone (such as acetylacetone), and amino alcohol (such as triethanolamine).

In the water-resistant composition of the present invention, the modified PV
The weight blending ratio [(A) / (B)] of A (A) and the organic titanium compound (B) having a chelate type ligand is 99.
It is important that the ratio is 99 / 0.01 to 60/40,
Preferably it is 99.97 / 0.03 to 70/30,
99.95 / 0.05 to 80/20 is more preferable, and 9
9/1 to 85/15 are more preferred, and 99/1 to 87 /
13 is particularly preferred. (A) / (B) is 99.99 /
If it exceeds 0.01, the water-resistant effect is low as shown in Comparative Example 3 described below, and if it is less than 60/40, the solution gels as shown in Comparative Example 6 described below, which is not preferable.

Thus, in the present invention, a specific modified PVA, that is, PVA having 1 to 20 mol% of α-olefin units having 4 or less carbon atoms, and αA having 4 or less carbon atoms.
-Having at least one type of modified PVA (A) selected from PVA having 1 to 20 mol% of olefin units and 0.01 to 1 mol% of silyl groups, and a specific organic titanium compound, that is, a chelate type ligand; The organotitanium compound (B) is uniformly mixed, and the specific P
VA (A) and a specific organotitanium compound (B) are mixed at a specific weight ratio, that is, [(A) / (B)] is 99.99.
By using a ratio of /0.01 to 60/40,
After coating the composition comprising (A) and (B) on a substrate,
Alternatively, even when treated at a relatively low temperature after film formation, that is, at 70 ° C. or lower, particularly around room temperature to 50 ° C., and even around room temperature, it exhibits excellent water resistance, especially boiling water resistance, and (A) and (B)
It is surprising that an aqueous solution obtained by uniformly mixing the above exhibits excellent low temperature storage viscosity stability.

The water-resistant composition of the present invention comprises a homogeneous mixture of the above-mentioned specific modified PVA (A) and an organotitanium compound (B) having a chelate type ligand, and comprises (A) and (B) Weight blending ratio is (A) / (B) = 99.99 /
The essential condition is 0.01 to 60/40, but a solvent, various additives, another water-soluble resin, an aqueous polymer dispersion or the like can be contained depending on the use.
As a solvent, water is preferably used, and a solvent such as various alcohols, ketones, dimethylformamide, and dimethylsulfoxide can be used in combination. Examples of the additives include various antifoaming agents, various dispersants, nonionic or anionic surfactants, silane coupling agents, pH regulators, and fillers such as calcium carbonate, clay, talc, and flour. Examples of the water-soluble resin include carboxymethylcellulose, cellulose derivatives such as hydroxyethylcellulose, poly (meth) acrylic acid, polyhydroxy (meth) acrylate or a copolymer thereof,
(Meth) acrylic polymers such as polyacrylamide, polyvinylpyrrolidone or a copolymer thereof, polyvinylacetamide, modified PVA containing a carboxyl group, modified PVA containing a sulfate group, modified PVA containing a sulfonic acid group, modified PVA containing a phosphoric acid group, Modified PVA containing secondary ammonium base
And general PVA and the like.
Examples of the aqueous polymer dispersion include aqueous dispersions of acrylic polymers and copolymers, ethylene-vinyl acetate copolymers, vinyl ester polymers and copolymers, and styrene-butadiene copolymers.

In the present invention, it is important that the component (A) and the component (B) are a homogeneously mixed composition. As a method of uniformly mixing, the component (A) and the component (B) are used. Are dissolved or dispersed in a solvent, preferably water, or a method of mixing an aqueous solution of the component (A) with an aqueous solution of the component (B). Modified PVA (A)
When the molded product of Example 1, for example, a film is immersed in an aqueous solution of an organotitanium compound (B) having a chelate type ligand, the components (A) and (B) are not uniformly mixed, and thus a comparative example described later. As is clear from FIG. 13, a molded product excellent in water resistance, which is the object of the present invention, cannot be obtained.

After the composition comprising the above (A) and (B) of the present invention is formed or coated on a substrate, the composition is dried or heat-treated at a low temperature, such as near room temperature, to obtain not only cold water but also hot water or boiling water. Since a sufficient water resistance effect can be obtained even with water, it is not usually necessary to perform the treatment at a particularly high temperature.However, it is not possible to perform drying or heat treatment at a high temperature to obtain a higher water resistance effect. There is no problem depending on the application. However, in this case, it is not preferable to perform the treatment at an extremely high temperature, because the coating of the composition or the like may rarely be colored. In general, a heat treatment at about 70 ° C. is sufficient.

The composition comprising the above (A) and (B) of the present invention makes use of water resistance in low-temperature treatment, and excellent film forming properties and film strength to make use of inorganic materials, paper, and various kinds of materials. It is effectively used as a coating agent for organic materials such as resin base materials, particularly as a surface coating agent for paper and various resin films. Here, examples of the resin film include films such as polyester, polystyrene, polyamide, polyvinyl chloride, polymethyl methacrylate, cellulose acetate, polycarbonate, and polyimide. Further, the composition of the present invention is a recording material, especially a coating layer of a heat-sensitive recording material that cannot be heat-treated at a high temperature,
Particularly, it is used very effectively for the overcoat layer. The water-resistant composition of the present invention includes an inorganic or organic adhesive or binder, a coating vehicle, a dispersant such as a pigment dispersion, a polymerization stabilizer or a post-additive for a crosslinkable emulsion, a gelatin blend or a photosensitive resin. It can be widely used for an image forming material, a substrate for hydrogel such as a cell-fixed gel or an enzyme-fixed gel, and also for applications where a water-soluble resin has been conventionally used. Furthermore, it can be used for molded products such as films, sheets, and fibers.

[0032]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. In the examples, unless otherwise noted.
“%” And “parts” mean “% by weight” and “parts by weight”, respectively.

Swelling degree and dissolution rate of sheet material The swelling degree and dissolution rate of sheet material in the following examples were calculated as follows. Swelling degree (fold) = b / (axe / d) Elution rate (%) = [{(axe / d) -c} / (axe
/ D)] × 100 a: Weight (g) of sheet before dipping b: Weight (g) of sheet pulled up after dipping in water at 20 ° C. for 24 hours c: Dip for 24 hours in water at 20 ° C. After pulling up, 105 ° C
(G) after drying for 24 hours at d: Weight (g) of sheet cut separately d: Weight (g) after drying the sheet cut at d at 105 ° C. for 24 hours

Representative modified PVA used in the following examples
A synthesis example of (two types of PVAs, PVA-1 and PVA-5) will be described. Synthesis Example 1 Synthesis Example of PVA Having Ethylene Unit Vinyl acetate 59.2k was placed in a 100-L pressure reactor equipped with a stirrer, a nitrogen inlet, an ethylene inlet, and an initiator inlet.
g of methanol and 6.2 kg of methanol, the temperature was raised to 60 ° C., and the system was purged with nitrogen for 30 minutes by nitrogen bubbling.
Then, ethylene was introduced and charged so that the pressure in the reaction tank became 0.6 MPa. A 2.8 g / L solution of 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) dissolved in methanol as an initiator was prepared.
Nitrogen was replaced by bubbling with nitrogen gas. After adjusting the inside temperature of the reaction vessel to 60 ° C., 66 mL of the above-described initiator solution was injected, and polymerization was started. During the polymerization, ethylene was introduced to adjust the reaction tank pressure to 0.6 MPa and the polymerization temperature to 6 MPa.
Maintained at 0 ° C., the above initiator solution was continuously added at 200 mL / hr. After 4 hours, when the conversion reached 40%, the system was cooled to stop the polymerization. After the reactor was released and ethylene was removed, nitrogen gas was bubbled through to completely remove ethylene. Then, unreacted vinyl acetate monomer was removed under reduced pressure to obtain a methanol solution. The solution adjusted to 20% had a molar ratio (moles of NaOH / polyvinyl acetate (P
Saponification was performed by adding a 0.05 mol / l solution of NaOH in methanol (10% concentration). Modified P obtained
The degree of saponification of VA (PVA-1) was 98.4 mol%.

A methanol solution of PVAc obtained by removing the polymerized and unreacted vinyl acetate monomer was precipitated in n-hexane and reprecipitated by dissolving in acetone three times.
Drying under reduced pressure at 0 ° C. yielded purified PVAc. The ethylene modification amount of the PVAc determined by proton NMR measurement was 4.5.
Mole%. After saponifying the above methanol solution of PVAc at an alkali molar ratio of 0.2, methanol Soxhlet was performed for 3 days, and then dried to obtain purified PVA. The average degree of polymerization of the PVA was determined according to the standard method of JIS K6726.
It was 1550 when measured according to.

Synthesis Example 2 Synthesis Example of PVA Having Silyl Group and Ethylene Unit A vinyl acetate (51.6 k) was placed in a 100-L pressure reactor equipped with a stirrer, a nitrogen inlet, an ethylene inlet, and an initiator inlet.
g, 13.7 kg of methanol and 111.0 g of vinyltrimethoxysilane, the temperature was raised to 60 ° C., and the system was replaced with nitrogen by bubbling nitrogen for 30 minutes. Then, ethylene was introduced and charged so that the reaction tank pressure became 0.65 MPa. A 2.8 g / L solution of 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) dissolved in methanol as an initiator was prepared, and the solution was replaced with nitrogen by bubbling with nitrogen gas. After adjusting the inside temperature of the reaction vessel to 60 ° C., 126 mL of the initiator solution was used.
And the polymerization was started. During the polymerization, ethylene was introduced to maintain the reactor pressure at 0.65 MPa and the polymerization temperature at 60 ° C., and the above initiator solution was continuously added at 390 mL / hr. After 4 hours, when the conversion reached 50%, the mixture was cooled to stop the polymerization. After the reactor was released and ethylene was removed, nitrogen gas was bubbled through to completely remove ethylene. Then, unreacted vinyl acetate monomer was removed under reduced pressure to obtain a methanol solution. The molar ratio (mol number of NaOH / mol number of polyvinyl acetate) was added to the solution adjusted to 25%.
Saponification was performed by adding a 0.05% NaOH methanol solution (10% concentration). Obtained modified PVA (PVA-5)
Was 98.2 mol%.

A methanol solution of PVAc obtained by polymerization and removal of unreacted vinyl acetate monomer is precipitated three times in n-hexane and dissolved in acetone for reprecipitation three times.
It dried under reduced pressure at ° C, and obtained purified PVAc. The amount of ethylene modification of the PVAc determined by proton NMR measurement was 6.5 mol%, and the amount of vinyl trimethoxysilane modification was 0.25 mol%. After saponifying the above methanol solution of PVAc at an alkali molar ratio of 0.2, methanol Soxhlet was performed for 3 days, and then dried to obtain purified PVA.
The average degree of polymerization of the PVA was 1030 when measured according to JIS K6726 of a conventional method.

Example 1 The PVA-1 obtained in Synthesis Example 1 (polymerization degree: 1550, saponification degree: 98.4 mol%, ethylene modification amount: 4.5 mol%) was dissolved in water to prepare a 4.5% aqueous solution. . This P
To 100 parts of the aqueous VA solution, 1.1 parts of TC-310 (a 45% solution of titanium lactate manufactured by Matsumoto Pharmaceutical Co., Ltd.) (0.5 parts as a pure titanium lactate) was added to give a 5% concentration of the water-resistant composition. A homogeneous mixed aqueous solution was prepared. This solution was cast and dried at 20 ° C. to obtain a colorless and transparent sheet (thickness: 100 μ). When the degree of swelling and the dissolution rate after immersing the obtained sheet in water (20 ° C.) for 24 hours were measured, the swelling degree was 7.7 times and the dissolution rate was 26%. Further, when the sheet was immersed in hot water in a boiling water bath for 1 hour and then pulled up, the sheet-like material maintained a firm shape and had no sliminess on the surface. Then, TCA was added to 100 parts of a 9% aqueous solution obtained by dissolving PVA-1 in water.
2.2 parts of 310 (1 part as pure titanium lactate)
In addition, a 10% concentration homogeneously mixed aqueous solution of the water-resistant composition was prepared. This solution had an aqueous solution viscosity (η0d) at 5 ° C. measured by a B-type viscometer immediately after preparation of the solution, which was 1630 m
Pa · s. After the solution was allowed to stand at 5 ° C. for one week and the viscosity was measured again, the aqueous solution viscosity (η7d) was 3
900 mPa · s, thickening ratio (η7d / η0d)
Was 2.4 times, and the low temperature storage viscosity stability was good.

Comparative Example 1 Example 1 was repeated except that PVA-9 having a polymerization degree of 1550 and a saponification degree of 98.4 mol% shown in Table 1 was used instead of PVA-1 (ethylene-modified) used in Example 1. A sheet (thickness: 100 μ) was obtained in the same manner as in the above. When the degree of swelling and dissolution rate of this sheet were measured in the same manner as in Example 1, the degree of swelling in water (20 ° C.) was 16 times and the dissolution rate was 45%. When the sheet was immersed in hot water in a boiling water bath for 1 hour, the shape of the sheet remained but was considerably brittle and could not be lifted. When a 10% aqueous solution of the composition was left at 5 ° C., the solution gelled after one day.

Examples 2 to 11 and Comparative Examples 2 to 11 The same procedures as in Example 1 were carried out except that the PVA-1 and TC-310 used in Example 1 and the amounts added were changed as shown in Tables 1 and 2. Performed similarly. Table 2 shows the results.

COMPARATIVE EXAMPLE 12 In place of PVA-1 (ethylene-modified) used in Example 1, PVA-11 having a polymerization degree of 1550, a saponification degree of 98.4 mol%, and an ethylene modification amount of 23 mol% was used. Example 1
An attempt was made to produce a sheet-like material in the same manner as described above, but since PVA-11 was not completely dissolved in water, water / methanol = 90/10
(Weight ratio) in the same manner as in Example 1 except that PVA-11 was dissolved using a mixed solvent (thickness of 100).
μ) was obtained. Although the obtained sheet was colorless,
It was translucent and cloudy glass. When the swelling degree and dissolution rate of this sheet were measured in the same manner as in Example 1, the swelling degree in water (20 ° C.) was 8.6 times and the dissolution rate was 35%. Place the sheet in hot water in a boiling water bath.
After immersion for a time, the sheet was completely disintegrated and could not be lifted. In addition, 10 of the composition
% Solution (solvent water / methanol = 90/10) was left at 5 ° C., and the solution gelled after one day.

Comparative Example 13 PVA-1 was dissolved in water to prepare a 5% aqueous solution of PVA-1. This aqueous solution was cast and dried at 20 ° C. to obtain a colorless and transparent sheet (thickness: 100 μ). The sheet was immersed in a 5% aqueous solution of titanium lactate (TC-310) and dried at 20 ° C. When the water resistance of the obtained sheet was measured in the same manner as in Example 1, the swelling degree was 8.3 times and the dissolution rate was 36%. When the sheet was immersed in hot water in a boiling water bath for 1 hour, the sheet was completely collapsed and could not be lifted.

[0043]

[Table 1]

[0044]

[Table 2]

1) ◎: small swelling, shape retention…: large swelling, shape retention △: unpullable (collapse) x: complete collapse 2) gelling in one day after standing 3) cyan-n-ethoxy titanium titanium The solution gelled when ethanol aminate was added 4) Gelled in 2 days after standing 5) Cloudy glass 6) PVA sheet immersed in titanium lactate aqueous solution 7) Countless cracks on the surface of the sheet Outbreak

[0046]

The water-resistant composition of the present invention can be used after film formation or after coating on a substrate, at 70 ° C. or lower, especially around room temperature to 50 ° C.
Even when drying or heat-treating at a relatively low temperature, such as around ℃ or even at room temperature, it has remarkably excellent water resistance not only to cold water but also to warm water and hot water, and has no problems such as viscosity stability and safety. Is also excellent.

Claims (4)

[Claims] (1) an α-olefin unit having 4 or less carbon atoms
At least one selected from a vinyl alcohol polymer having from 20 to 20 mol% and a vinyl alcohol polymer having from 1 to 20 mol% of an α-olefin unit having 4 or less carbon atoms and from 0.01 to 1 mol% of a silyl group; A homogeneous mixture of a modified vinyl alcohol polymer (A) and an organotitanium compound (B) having a chelate type ligand,
(A) / (B) Weight blending ratio of component (A) and component (B)
Is 99.99 / 0.01 to 60/40. 2. Modified vinyl alcohol polymer (A)
The water-resistant composition according to claim 1, which is a vinyl alcohol polymer having 1 to 20 mol% of α-olefin units having 4 or less carbon atoms and 0.01 to 1 mol% of a silyl group. 3. An α-olefin unit having 4 or less carbon atoms,
The water-resistant composition according to claim 1, which is an ethylene unit. 4. The water-resistant composition according to claim 1, wherein the organotitanium compound (B) having a chelate type ligand is at least one selected from titanium lactate and a partially or completely neutralized product thereof.