JP2002284818A - Novel vinyl alcohol resin and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel vinyl alcohol resin excellent in viscosity stability of its aqueous solution, high-speed applicability, and water solubility; and its use. SOLUTION: This novel vinyl alcohol resin contains 1,2-glycol units as side chains. Its use includes an adhesive, a molded article, a coating agent, an emulsifier, and a suspension agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel vinyl alcohol resin containing a 1,2-glycol component in a side chain,
In particular, the present invention relates to a polyvinyl alcohol-based resin, and more particularly, to a novel vinyl alcohol-based resin having excellent viscosity stability of an aqueous solution and its use.

[0002]

2. Description of the Related Art Hitherto, polyvinyl alcohol resins have been used as emulsifiers, suspending agents, surfactants, and fiber processing by utilizing their film forming properties (film forming properties, oil resistance, strength, etc.) and water solubility. It is widely used as agents, various binders, paper processing agents, adhesives, films and the like. And, except for special cases, it is usually used as an aqueous solution. Depending on the purpose of use, polyvinyl alcohol of various degrees of saponification is used, but when using a relatively high degree of saponification polyvinyl alcohol-based resin, when dissolved in water to form an aqueous solution, such as in winter when the water temperature is low, The viscosity of the aqueous solution increases with time and the fluidity deteriorates. In an extreme case, the aqueous solution may gel and lose the fluidity at all, which is a serious problem.

As a method for improving the low-temperature viscosity stability of such an aqueous solution of a polyvinyl alcohol-based resin, there are methods such as lowering the degree of saponification, introducing a hydrophobic group, and introducing an ionic group. The method of introducing a hydrophobic group has the disadvantage that, when dissolving a polyvinyl alcohol-based resin, it is necessary to dissolve the polyvinyl alcohol-based resin at a considerably high temperature or the cloud point is lowered. Further, the method of introducing an ionic group has a disadvantage that the water resistance of the dried film is low. Further, polyvinyl alcohol resins having a low degree of saponification have problems such as generation of acetic acid odor when applied to films and the like, and are disliked in packaging applications for foods and cosmetics. Further, as a water-soluble film for unit packaging, a film made of a partially saponified polyvinyl alcohol-based resin having a low degree of saponification has been used because of its excellent cold water solubility and mechanical strength. However, in the case of the type of medicine to be packed, for example, an alkaline medicine (borax, sodium carbonate, various detergents),
There is a problem in that saponification gradually progresses during storage and the water becomes insoluble or hardly soluble in cold water due to a change to a completely saponified polyvinyl alcohol resin.

To improve the low-temperature viscosity stability of an aqueous solution of a polyvinyl alcohol-based resin, Japanese Patent Application Laid-Open No. H11-279210 discloses that the pressure in a polymerization machine is reduced from the atmospheric pressure during the polymerization of an aliphatic vinyl ester. And the reaction temperature is higher than the boiling point of the reaction solution at atmospheric pressure by 2
Polyvinyl alcohol obtained by polymerizing at a temperature higher by ~ 80 ° C and saponifying the obtained aliphatic polyvinyl ester has been proposed. Further, JP-A-11-279986 discloses that the polyvinyl alcohol has good high-speed coating properties. It has been proposed that Japanese Patent Application Laid-Open No. 9-272775 discloses a technique for improving water solubility by modification with sulfonic acid.
A technique for improving water solubility by oxyalkylene modification is disclosed. Further, JP-A-9-272775 discloses that
There is disclosed a water-soluble film technique in which a polyhydric alcohol obtained by adding a predetermined amount of an alkylene oxide to a polyvinyl alcohol resin having a saponification degree of 50 to 99 mol% is added.

[0005]

However, Japanese Patent Application Laid-Open No. 11-279210 and Japanese Patent Application Laid-Open No.
In the technology disclosed in Japanese Patent No. 986, there is a problem that it is necessary to pressurize in order to raise the polymerization temperature, and it is necessary to provide a pressurizing facility in the production, and the obtained polyvinyl alcohol is contained in the main chain. Due to the presence of 1,2-glycol, a hydroxyl group is present as a secondary alcohol, and the reactivity with a cross-linking agent and the like is poor, and the heat resistance of polyvinyl alcohol is also poor, and there is a drawback that coloring is easy. . Further, it is not easy to control the amount of 1,2-glycol that can be introduced, and the viscosity stability of the aqueous solution and the coating property at the time of high-speed coating are not yet satisfactory, and further improvement is required. I have. Also, JP-A-11-2
In the technique disclosed in Japanese Patent No. 22546, it is not easy to increase the degree of polymerization of the polyvinyl alcohol-based resin, and it is difficult to obtain a polyvinyl alcohol-based resin film having high mechanical strength, and the film becomes hardly soluble in hard water. There are problems such as. In the oxyalkylene group modification disclosed in JP-A-63-168439, it is difficult to increase the degree of polymerization of the polyvinyl alcohol-based resin to 1000 or more, and the alkylene oxide is easily cleaved by an acid, and the water solubility of the film is reduced. However, there is a problem that it is easy to change with time. Furthermore, the technique disclosed in Japanese Patent Application Laid-Open No. 9-272775 has not yet solved the problem that the degree of saponification increases with time when an acidic substance or an alkaline substance is packaged.

Under such circumstances, in the present invention, the viscosity stability and aqueous solubility of the aqueous solution are excellent, the coating property at the time of high-speed coating and the adhesion to the adherend are excellent, and the crosslinking agent Novel vinyl alcohol-based resin (I) containing a 1,2-glycol component in the side chain, which has high reactivity with the like, contains a crosslinking agent and has excellent water resistance when formed into a film, and the novel vinyl alcohol It is also a precursor of the base resin (I),
A vinyl ester-based monomer (A) excellent in viscosity stability of an aqueous solution and excellent solubility in water as a film without odor such as acetic acid odor, and 2,2-dialkyl-4-vinyl represented by the general formula (3) It is an object of the present invention to provide a novel vinyl alcohol resin (II) obtained by saponifying a copolymer (AC) with -1,3-dioxolane (C), and its use.

[0007]

Means for Solving the Problems However, as a result of diligent studies on such a problem, the present inventors have found that 1,2-
The present inventors have found that a novel vinyl alcohol-based resin (I) containing a glycol component meets the above object, and have completed the present invention. In the present invention, the 1,2-formula represented by the general formula (1)
The novel vinyl alcohol-based resin (I) containing a glycol structural unit is preferred.

[0008]

Embedded image However, R ¹ , R ² and R ³ are each independently hydrogen or an alkyl group.

The novel vinyl alcohol resin (I) of the present invention is a copolymer (AB) of a vinyl ester monomer (A) and a vinyl ethylene carbonate (B) represented by the general formula (2). Or a copolymer of a vinyl ester monomer (A) and a 2,2-dialkyl-4-vinyl-1,3-dioxolane (C) represented by the general formula (3) (C) AC) is preferably obtained by saponifying and deketalizing, or it is preferable to saponify a copolymer (AD) of a vinyl ester monomer (A) and glycerin monoallyl ether (D). .

[0010]

Embedded image However, R ¹ , R ² and R ³ are each independently hydrogen or an alkyl group.

[0011]

Embedded image However, R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently hydrogen or an alkyl group.

In the present invention, a copolymer (A) of a vinyl ester monomer (A) and a 2,2-dialkyl-4-vinyl-1,3-dioxolane (C) represented by the general formula (3) is used. The novel vinyl alcohol (II) obtained by saponifying -C) is useful as a precursor of the above-mentioned vinyl alcohol (I) containing 1,2-glycol in the side chain. (II) itself has excellent viscosity stability of an aqueous solution and solubility in water as a film, and further has a lower melting point than modification so that moldability (extrusion molding,
(E.g., injection molding).

In the present invention, the novel vinyl alcohol resin (I) or (II) can be effectively used for various applications such as adhesives, molded products, coating agents, emulsifiers, suspending agents and the like.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The novel vinyl alcohol-based resin (I) of the present invention may contain a 1,2-glycol component in the side chain of the vinyl alcohol-based resin, and in particular, the 1,2-glycol represented by the above general formula (1) -It preferably contains a glycol structural unit. In the above general formula (1), R ¹ , R ² and R ³ are each independently hydrogen or an alkyl group. The alkyl group is not particularly limited, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group,
An alkyl group having 1 to 4 carbon atoms such as an isobutyl group and a tert-butyl group is preferred. Such an alkyl group is, if necessary, a halogen group, a hydroxyl group, an ester group, a carboxylic acid group,
It may have a substituent such as a sulfonic acid group.

In the present invention, the method for obtaining the novel vinyl alcohol resin (I), in particular, the polyvinyl alcohol resin is not particularly limited, but the vinyl ester monomer (A) and the vinyl represented by the general formula (2) are used. Copolymer with ethylene carbonate (B) (A
-B) a method of saponifying and decarboxylating vinyl ester monomer (A) and 2,2 represented by the above general formula (3)
Method of saponifying and deketalizing copolymer (AC) with dialkyl-4-vinyl-1,3-dioxolane (C), vinyl ester monomer (A) and glycerin monoallyl ether (D) And a copolymer (A-
The method of saponifying D) is preferably used. Hereinafter, the methods (1) to (4) will be described.

[Method] The vinyl ester monomers (A) used in the present invention include vinyl formate, vinyl acetate, vinyl propionate, vinyl valerate, vinyl butyrate, vinyl isobutyrate, vinyl pivalate, and vinyl caprate. , Vinyl laurate, vinyl stearate, vinyl benzoate, vinyl versatate and the like,
Among them, vinyl acetate is preferably used from the viewpoint of economy.

The vinyl ethylene carbonate (B) is not particularly limited as long as it has a structure represented by the above general formula (2). In the above general formula (2), R ¹ , R ² ,
As R ³ , those similar to the aforementioned general formula (1) can be mentioned. Among them, in terms of availability and good copolymerizability,
Vinylethylene carbonate in which R ¹ , R ² and R ³ are hydrogen is preferred.

In copolymerizing the vinyl ester monomer (A) with the vinyl ethylene carbonate (B), bulk polymerization, solution polymerization, suspension polymerization, dispersion polymerization,
Alternatively, a known method such as emulsion polymerization can be employed, but usually, solution polymerization is performed. There are no particular restrictions on the method of charging the monomer components during the polymerization, and any method such as batch charging, split charging, and continuous charging may be employed, but vinyl ethylene carbonate binate (B) is used in the molecular chain of the polyvinyl ester-based polymer. Drop polymerization is preferred from the viewpoints of uniform distribution of the polymer in water, improvement in reactivity with a cross-linking agent, and physical properties such as a decrease in the melting point of polyvinyl alcohol. Particularly, the HANNA method (reactivity ratio: r ( V
A polymerization method based on EC) = 5.4, r (VAc) = 0.85) is preferred.

Examples of the solvent used in the polymerization include lower alcohols such as methanol, ethanol, propanol and butanol, and ketones such as acetone and methyl ethyl ketone. The amount of the solvent used may be appropriately selected in consideration of the chain transfer constant of the solvent in accordance with the degree of polymerization of the target copolymer (AB). For example, when the solvent is methanol, S ( (Solvent) / M (monomer) =
0.01 to 10 (weight ratio), preferably 0.05 to 3
(Weight ratio).

In the copolymerization, a polymerization catalyst is used,
Examples of such a polymerization catalyst include known radical polymerization catalysts such as azobisisobutyronitrile, acetyl peroxide, benzoyl peroxide, and lauryl peroxide, and low-temperature active radicals such as azobisdimethylvaleronitrile and azobismethoxydimethylvaleronitrile. A polymerization catalyst and the like can be mentioned, and the amount of the polymerization catalyst used depends on the polymerization catalyst and cannot be unconditionally determined, but is arbitrarily selected according to the polymerization rate. For example, when azoisobutyronitrile or acetyl peroxide is used, the amount of azoisobutyronitrile or acetyl peroxide is 0.0
It is preferably from 1 to 0.2 mol%, particularly preferably from 0.02 to 0.1 mol%.
5 mol% is preferred. The reaction temperature of the copolymerization reaction is 40
It is preferable that the temperature is from about ° C to the boiling point (depending on the solvent used).

In the present invention, the content of the vinyl ethylene carbonate (B) is not particularly limited, but may be from 0.1 to
The content is preferably 20 mol%, more preferably 0.1 mol%.
It is 5 to 15 mol%, particularly preferably 1 to 10 mol%, particularly preferably 2 to 7 mol%. When the content of the vinyl ethylene carbonate (B) is less than 0.1 mol%, reactivity with a crosslinking agent or the like is low, and no improvement effect is observed in terms of viscosity stability of the aqueous solution. The workability is also lowered, and if it exceeds 20 mol%, the water resistance of the polyvinyl alcohol-based resin coating is lowered, which is not preferable.

The vinyl monomer (A) thus obtained
Copolymer (A) with vinyl ethylene carbonate (B)
-B) is then saponified and decarboxylated. The saponification is carried out by dissolving the copolymer (AB) in an alcohol or a hydrous alcohol and using an alkali catalyst or an acid catalyst. Examples of the alcohol include methanol, ethanol, propanol, tert-butanol and the like, and methanol is particularly preferably used. The concentration of the copolymer (AB) in the alcohol is appropriately selected depending on the viscosity of the system, but is usually selected from the range of 10 to 60% by weight. Examples of the catalyst used in the saponification include alkali hydroxides such as sodium hydroxide, potassium hydroxide, sodium methylate, sodium ethylate, potassium methylate, and lithium methylate; alkali catalysts such as alcoholate; sulfuric acid; Hydrochloric acid, nitric acid, metasulfonic acid,
Acid catalysts such as zeolites and cation exchange resins are exemplified.

The amount of the saponification catalyst to be used is appropriately selected depending on the saponification method, the target degree of saponification, and the like. When an alkali catalyst is used, it is usually used with respect to the vinyl ester monomer (A). 0.1 to 30 mol%, preferably 2 to 15 mol% is suitable. Further, the reaction temperature of the saponification reaction is not particularly limited, but is preferably from 10 to 150 ° C, more preferably from 10 to 60 ° C, particularly preferably from 20 to 50 ° C.

In the present invention, decarboxylation is usually carried out together with the saponification under the above-mentioned saponification conditions without any special treatment after saponification, and the ethylene carbonate ring is opened. , 2-glycol component. Thus, a novel vinyl alcohol-based resin containing a 1,2-glycol component in the side chain of the present invention, particularly a polyvinyl alcohol-based resin can be obtained. In addition, under a constant pressure (normal pressure to 100 kg / cm ² ) and at a high temperature (50 to ² kg).
00 ° C) without saponifying the vinyl ester moiety.
It is also possible to perform decarboxylation, and in such a case, after performing decarboxylation, the above saponification can also be performed.

[Method] 2,2- used in the present invention
Dialkyl-4-vinyl-1,3-dioxolane (C)
Is not particularly limited as long as it has a structure represented by the general formula (3). In the general formula (3),
R ¹ , R ² , and R ³ are the same as those in the above general formula (1), and R ⁴ and R ⁵ are each independently hydrogen or an alkyl group, and the alkyl group is not particularly limited. For example, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group and a tert-butyl group is preferable. Such an alkyl group may have a substituent such as a halogen group, a hydroxyl group, an ester group, a carboxylic acid group, and a sulfonic acid group, if necessary. Among them, from the viewpoint of availability and good copolymerizability, 2,2-dimethyl-4-vinyl-1,2 in which R ¹ , R ² , and R ³ are hydrogen and R ⁴ and R ⁵ are methyl groups. 3-Dioxolane is preferred.

The copolymerization of the vinyl ester monomer (A) with 2,2-dialkyl-4-vinyl-1,3-dioxolane (C) is carried out in the same manner as described above.

In the present invention, 2,2-dialkyl-
The content of 4-vinyl-1,3-dioxolane (C) is not particularly limited, but is preferably 0.1 to 20 mol%, more preferably 0.5 to 15 mol%, and particularly preferably 1 to 15 mol%. 10 mol%. When the content of the 2,2-dialkyl-4-vinyl-1,3-dioxolane (C) is less than 0.1 mol%, a crosslinking agent for a polyvinyl alcohol-based resin having 1,2-glycol obtained in a side chain thereof is obtained. Is low in reactivity with water, the viscosity stability of the aqueous solution is inferior, and the effect of improving the coating property at the time of high-speed coating is not recognized. If it exceeds 20 mol%, the crystallinity of the polyvinyl alcohol resin is low. It is not preferable because the water resistance is lowered, probably because it is too formed.

The vinyl monomer (A) thus obtained
The copolymer (A-C) of 2,2-dialkyl-4-vinyl-1,3-dioxolane (C) is then saponified and deketalized. Saponification is performed in the same manner as in the above method.

The saponified product of the copolymer (AC) after saponification (before deketalization) is a novel vinyl alcohol-based resin (II) per se and contains 1,2-glycol in the side chain. It is useful as a precursor of the vinyl alcohol resin (I). Such a novel vinyl alcohol resin (I
I) In particular, the polyvinyl alcohol resin is excellent in viscosity stability of an aqueous solution, easy solubility in water, coatability on paper at high speed coating, and easy solubility even in a completely saponified product. A film is obtained, and there is an advantage that acetic acid odor which is a problem in partially saponified PVA is not recognized. Further, since the melting point drop is large, it is advantageous in terms of moldability such as extrusion molding and injection molding. Further, even when reacting with a crosslinking agent such as a methylolated melamine resin or an isocyanate, the reactivity is low in the state of the vinyl alcohol-based resin (II), but the aqueous solution is made acidic and deketalization is performed to increase the reaction rate. There are also advantages such as controllability.

Regarding the deketalization of the saponified product of the copolymer (AC), when the saponification is carried out using an alkali catalyst, the saponification is carried out and then the aqueous solvent (acid) is used using an acid catalyst. Water, water / acetone, mixed solvent of lower alcohols such as water / methanol, etc.)
It is converted to a 1,2-glycol component. Acid catalysts used for deketalization include acetic acid, hydrochloric acid, sulfuric acid, nitric acid,
Examples include metasulfonic acid, zeolite, and cation exchange resin. Further, when the saponification is performed using an acid catalyst, usually, without performing any special treatment after the saponification,
Under the above-mentioned saponification conditions, deketalization is carried out together with the saponification to be converted into a 1,2-glycol component. Thus, a novel vinyl alcohol-based resin (I) containing a 1,2-glycol component in the side chain of the present invention, in particular, a polyvinyl alcohol-based resin can be obtained.

[Method] In the above method, it can be obtained by using glycerin monoallyl ether (D) in place of vinylethylene carbonate (B). It is preferable to adopt a method such as charging, divided charging, continuous charging, and the like, and it is also possible to perform drop polymerization.
When azoisobutyronitrile or acetyl peroxide is used, the amount of the polymerization catalyst used is preferably 0.05 to 0.7 mol% with respect to the vinyl ester monomer (A). The content is preferably 0.1 to 0.5 mol%. When glycerin monoallyl ether (D) is used as a copolymer monomer, a vinyl alcohol-based resin containing a 1,2-glycol component, particularly, a polyvinyl alcohol-based resin containing a 1,2-glycol component is naturally used without decarboxylation. Obtainable.

In the present invention, a novel vinyl alcohol-based resin (I) and a novel vinyl alcohol (II) can be obtained by the above-mentioned methods (1) to (4). The degree of polymerization of is suitably selected according to the purpose of use, and is not particularly limited.
~ 4000, more preferably 300 ~ 260
0, particularly preferably 500 to 2200. If the degree of polymerization is less than 300, the strength of the coating film or film obtained by reacting with the crosslinking agent is low, and if it exceeds 4000, the amount of modification of 1,2 glycol is introduced within the range of the amount of modification intended for the present invention. It is not preferable because it becomes difficult. Similarly, the polymerization degree of the vinyl alcohol resin (II) of the present invention is also 300.
To 4000, preferably 300 to 2600, more preferably 500 to 2200.

The degree of saponification of the vinyl alcohol resin (I) or (II) of the present invention is not particularly limited.
It is preferably from 3 to 100 mol%, more preferably from 75 to 1 mol%.
00 mol%, particularly preferably 85 to 100 mol%, more preferably 98.1 to 100 mol%. Particularly preferably, 99.5 to 100 mol%. If the saponification degree is less than 63 mol%, the water solubility is undesirably low. Also, a vinyl monomer (A) and a vinyl ethylene carbonate (B) or 2,2-dialkyl-4-vinyl-1,3-
In addition to dioxolane (C) or glycerin monoallyl ether (D), copolymerizable components such as ethylene, propylene, isobutylene, α-octene, α-dodecene, α
It is also preferable to copolymerize an α-olefin such as octadecene to obtain an α-olefin-vinyl alcohol-based resin from the viewpoint of the viscosity stability of the aqueous solution of the vinyl alcohol-based resin, and the content of the α-olefin is 0.1 to 10 mol. %, Particularly preferably 2 to 8 mol%.

Further, another unsaturated monomer can be copolymerized as a copolymerizable component. As the unsaturated monomer, for example, vinylene carbonates, acrylic acid, methacrylic acid, crotonic acid, maleic acid, maleic anhydride,
Unsaturated acids such as itaconic acid or salts thereof or mono- or dialkyl esters; nitriles such as acrylonitrile and methacrylonitrile; amides such as diacetone acrylamide, acrylamide and methacrylamide; ethylene sulfonic acid, allyl sulfonic acid and methallyl sulfone Olefinsulfonic acids such as acids or salts thereof, alkyl vinyl ethers, dimethylallyl vinyl ketone, N-vinylpyrrolidone, vinyl chloride, vinylidene chloride, polyoxyethylene (meth) allyl ether,
Polyoxyalkylene (meth) allyl ether such as polyoxypropylene (meth) allyl ether, polyoxyethylene (meth) acrylate, polyoxyalkylene (meth) acrylate such as polyoxypropylene (meth) acrylate, polyoxyethylene (meth) Acrylamide, polyoxyalkylene (meth) acrylamide such as polyoxypropylene (meth) acrylamide,
Polyoxyethylene (1- (meth) acrylamide-
1,1-dimethylpropyl) ester, polyoxyethylene vinyl ether, polyoxypropylene vinyl ether, polyoxyethylene allylamine, polyoxypropylene allylamine, polyoxyethylene vinylamine, polyoxypropylene vinylamine and the like.

Further, N-acrylamidomethyltrimethylammonium chloride, N-acrylamidoethyltrimethylammonium chloride, N-acrylamidopropyltrimethylammonium chloride, 2-acryloxyethyltrimethylammonium chloride,
2-methacryloxyethyltrimethylammonium chloride, 2-hydroxy-3-methacryloyloxypropyltrimethylammonium chloride, allyltrimethylammonium chloride, methallyltrimethylammonium chloride, 3-butenetrimethylammonium chloride, dimethyldiallylammonium chloride, diethyldiallylammonium chloride, etc. And acetoacetyl group-containing monomers. By setting the polymerization temperature to 100 ° C. or higher, it is possible to use a PVA main chain in which 1,2-glycol is introduced.

Thus, a novel vinyl alcohol-based resin (I) containing a 1,2-glycol component in the side chain is obtained, and the vinyl alcohol-based resin (I) has a very excellent effect on the viscosity stability of the aqueous solution. In addition, since a hydroxyl group is present as a primary alcohol, an isocyanate compound,
It also has high reactivity with crosslinking agents such as polyamide epichlorohydrin, glyoxal, melamine resins, methylolmelamine, and methylolated bisphenol S.
Also, it has good coatability without thickening even under high shear during high-speed coating. Above all, the isocyanate-based compound is a compound having two or more isocyanate groups in a molecule, for example, tolylene diisocyanate (TDI), hydrogenated TDI, trimethylolpropane-TDI adduct (for example, “Des, manufactured by Bayer AG,
modur L "), triphenylmethane triisocyanate, methylenebisdiphenyl isocyanate (MD
I), hydrogenated MDI, polymerized MDI, hexamethylene diisocyanate, xylylene diisocyanate, 4,4-
Examples include dicyclohexylmethane diisocyanate and isophorone diisocyanate. In addition, a prepolymer having a terminal group having an isocyanate group, which is previously polymerized with an excess of a polyisocyanate in a polyol, may also be used. As the compounding ratio of the isocyanate compound, the molar ratio of isocyanate group to hydroxyl group (NCO / O
H) is preferably from 0.1 to 2.

A novel vinyl alcohol obtained by saponifying a copolymer (AC) of a vinyl ester monomer (A) and 2,2-dialkyl-4-vinyl-1,3-dioxolane (C) II) is obtained as a precursor of a vinyl alcohol-based resin (I) containing a 1,2-glycol component in the side chain, and as such, has an effect on the viscosity stability of the aqueous solution, the solubility in water, and the moldability. It has excellent effects.

Further, the vinyl alcohol resin (I) or (II) of the present invention can be used for various applications by utilizing its properties, and specific examples thereof include the following. (1) Adhesives Adhesives for wood, paper, aluminum foil, plastics, etc., adhesives, re-wetting agents, binders for nonwoven fabrics, binders for various building materials such as gypsum boards and fiber boards, binders for various powder granulations, Examples thereof include additives for cement and mortar, hot-melt adhesives, pressure-sensitive adhesives, and fixing agents for anionic paints.

(2) Molded articles Fibers, films (especially water-soluble films for packaging articles such as agricultural chemicals, detergents, laundry clothes, civil engineering additives, bactericides, dyes, pigments, etc.), sheets, pipes, tubes, Examples thereof include a leak-proof film, a provisional film, for a chemical lace, and a water-soluble fiber, and are particularly useful when used as such a water-soluble film. Such uses will be described in further detail.

The saponification degree of the vinyl alcohol-based resin (polyvinyl alcohol-based resin) when used for such a film application is preferably from 65 to 98 mol%, and further, from the viewpoint of easy water solubility imparted with acid resistance and alkali resistance. Based resin (I) is preferred, and the degree of saponification at that time is 98.
It is preferably from 1 to 100 mol%, more preferably from 99 mol% to 10 mol%.
0 mol% is preferred. Such saponification degree is 98.1 mol%
If it is less than 1, it is not preferable because the water solubility of the film decreases with time when a drug or the like comprising an acidic substance or an alkaline substance is contained and stored. The amount of modification of 1,2-glycol for use in drug packaging is preferably 0.5 to 15 mol%, more preferably 1 to 10 mol%, particularly 3 to 7 mol%, particularly 4 to 7 mol%. % Is preferable, and when the modification amount is less than 0.5 mol%, the solubility of the film in cold water decreases,
Conversely, if it exceeds 15 mol%, the crystallinity will be too low,
The film strength is undesirably reduced. The average degree of polymerization of the vinyl alcohol-based resin when used for a film is preferably from 400 to 4000, and more preferably from 500 to 2
600, especially 550-2000, especially 700-180
If the average degree of polymerization is less than 400, the mechanical strength, toughness, and impact resistance of the film decrease. If the average polymerization degree exceeds 4,000, the solution viscosity at the time of preparing the film increases and molding becomes difficult. This is not preferable because bubbles in the solution cannot be removed.

The method for producing a film using the vinyl alcohol resin of the present invention is not particularly limited, and is appropriately selected depending on the required film thickness and intended use. Usually, a cast film forming method from a vinyl alcohol-based resin, a dry film forming method [extrusion into an inert gas such as air or nitrogen], a wet film forming method [the vinyl alcohol-based resin (I) is used in a poor solvent. Extrusion] and a gel film forming method. Examples of the solvent used when preparing the vinyl alcohol-based resin solution include dimethyl sulfoxide, dimethylformamide, dimethylacetamide, ethylene glycol, glycerin, water, hexafluoroisopropyl alcohol, and the like. Also, lithium chloride,
An aqueous solution of an inorganic salt such as calcium chloride can be used alone or in combination with the above organic solvent. Among these, water, dimethyl sulfoxide, a mixed solution of dimethyl sulfoxide and water, glycerin, and ethylene glycol are preferred. The concentration of the vinyl alcohol-based resin solution used during film formation varies depending on the film formation method, but is usually 10 to 60% by weight, and the temperature during film formation is usually in the range of room temperature to 250 ° C. After film formation, if necessary, uniaxial or biaxial stretching or rolling can be performed. The temperature at the time of stretching such a film is usually in the range of room temperature to 270 ° C. Further, by applying a heat treatment at about 100 to 150 ° C. after the film formation, the dissolution rate of the film can be controlled within a certain range. In order to improve the anti-blocking property and water solubility of the film, it is preferable to apply a matting process, an embossing process, or a spray of an anti-blocking agent on the film surface. The shape and transparency of the film are not particularly limited. The film thickness is
It is individually determined according to the type of the alkaline substance or the acidic substance, the amount of the alkaline substance or the acidic substance, the packaging form, and the dissolution rate, but usually about 20 to 100 μm is preferable.

In addition to the above alkaline substances and acidic substances, main packaging objects are chlorine-containing substances, substances having polyvalent metal salts such as copper and cobalt, polycarboxylic acid-containing substances, polyamine-containing substances, boric acid. Included substances, pesticides and the like. The alkaline substance is not particularly limited as long as the pH of the solution, dispersion, or slurry when dissolved or dispersed in water exceeds 7, but preferably the pH is 8 or more. Preferably, the pH is 8.5 or more,
More preferably, the pH is 9 or more. Specific examples include household clothing detergents, industrial clothing detergents, household dishwashing detergents, industrial dishwashing detergents, building and car detergents, industrial water detergents, inorganic powder dispersants, various surfactants, and the like. No. Individual drugs include alkali metal salts or alkaline earth metal salts of inorganic acids such as sodium carbonate, sodium bicarbonate, sodium silicate, sodium metasilicate, sodium phosphate, sodium polyphosphate, and sodium acetate, sodium succinate , Alkali metal salts of organic acids such as sodium tartrate, sodium stearate, and sodium polyacrylate; amine compounds; alkaloids; and the like, in the form of powder, slurry, gel, or a mixture of several of these. Any of the composite forms described above.

Agrochemicals are chemicals defined by the Agricultural Chemicals Control Law, and include, for example, fungicides and insecticides used for controlling animals such as fungi, nematodes, mites, and rats that harm crops and agricultural and forestry products. And the like. Specifically, germicidal spraying agents such as Bordeaux, soil such as chlorpicrin, seed disinfectant,
Examples include insecticides such as organic phosphorus and DDT, osmotic insecticides such as Schuldan, growth regulators such as naphthylacetic acid, attractants, and repellents.

In producing a molded article including the above-mentioned film, it is preferable to add a plasticizer. As the plasticizer, a trihydric to hexahydric alcohol (glycerin, trimethylolpropane, Glycerin, pentaerythritol, xylol, arabinose, ribulose, sorbitol, etc.), various alkylene oxides (ethylene oxide, propylene oxide, mixed adducts of ethylene oxide and propylene oxide, etc.)
Is mentioned. Further, gallic acid, salts of gallic acid, esters thereof and hydroxylcarboxylic acids having a reducing property (such as citric acid, tartaric acid and L-ascorbic acid) may be added.

(3) Coating agents Clear coating agent for paper, pigment coating agent for paper, sizing agent for paper, sizing agent for textiles, warp paste, fiber processing agent, leather finishing agent, paint, anti-fog agent, Metal corrosion inhibitor, brightener for galvanizing, antistatic agent, conductive agent,
Temporary paints, etc.

(4) Emulsifiers Ethylenically unsaturated compounds, butadiene compounds, emulsifiers for emulsion polymerization of various acrylic monomers, hydrophobic resins such as polyolefins and polyester resins, epoxy resins,
Post-emulsifiers such as paraffin, bitumen, etc.

(5) Suspending agents Pigment dispersion stabilizers such as paints, ink, aqueous color, adhesives, etc.
Dispersion stabilizers for suspension polymerization of various vinyl compounds such as vinyl chloride, vinylidene chloride, styrene, (meth) acrylate, and vinyl acetate;

(6) Blending Agent for Hydrophobic Resin An antistatic agent for a hydrophobic resin, a hydrophilicity-imparting agent, a composite fiber, a film and other additives for molded articles, etc.

(7) Thickeners Thickeners for various aqueous solutions and emulsions. (8) Flocculant-related flocculants for suspensions and dissolved substances in water, drainage of pulp and slurry, etc. (9) Soil conditioner-related (10) Photosensitizer, electron-sensitive, photosensitive resist resin, etc. (11) Other ion exchange resins, ion exchange membranes, chelate exchange resins, etc. Among the above, the utility is particularly expected for the uses (1) to (5).

[0050]

The present invention will be specifically described below with reference to examples. In the examples, “parts” and “%” mean on a weight basis unless otherwise specified.

Example 1 In a reaction vessel equipped with a reflux condenser, a dropping funnel and a stirrer, 1300 g of vinyl acetate (A), 260 g of methanol, and vinyl ethylene carbonate (B) (R ¹ , R ² and R ³ were all used) Hydrogen) (51.69 g, 3 mol%) was charged, azobisisobutyronitrile was charged at 0.04 mol% (based on the charged vinyl acetate monomer), and the temperature was increased under a nitrogen stream with stirring to carry out polymerization. went. Two hours after the start of polymerization, 0.04 mol% of azobisisobutyronitrile was further added.
(Vs. vinyl acetate monomer initially charged) was added, and the polymerization was further continued. Thereafter, the polymerization rate of vinyl acetate (A) was 8
When it reached 3.9%, the polymerization charged with the polymerization inhibitor was terminated. Subsequently, unreacted vinyl acetate monomer was removed from the system by a method of blowing methanol vapor to remove the copolymer (A).
A methanol solution of -B) was obtained.

Next, the solution was diluted with methanol, adjusted to a concentration of 30%, and charged into a kneader.
While maintaining the temperature at 0 ° C, a 2% methanol solution of sodium hydroxide was added in an amount of 8 mmol% with respect to the vinyl acetate (A) unit in the copolymer to perform saponification and decarboxylation. As the saponification and decarboxylation proceeded, the saponified product was precipitated, and finally became particulate. The produced polyvinyl alcohol was separated by filtration, washed well with methanol, and dried in a hot air drier to obtain an intended product.

The degree of saponification of the obtained polyvinyl alcohol was 99.2 mol% when analyzed by the amount of alkali consumed for hydrolysis of the remaining vinyl acetate units. The degree of polymerization was in accordance with JIS K 6726. As a result of analysis, it was 1260. The viscosity of a 4% aqueous solution of the polyvinyl alcohol was 15.4 mPa · s (20 ° C.) as measured by a Heppler viscometer, and the amount of modification was 2.7 mol% as calculated from NMR measurement. .

The assignment of IR spectrum and ¹ H-NMR (internal standard substance: tetramethylsilane, solvent: d6-DMSO) spectrum of the obtained polyvinyl alcohol was as follows. FIG. 1 shows an IR chart, and FIG. 2 shows an NMR chart. In addition, "2" manufactured by Hitachi, Ltd. was used for IR measurement.
70-30 "and NMR measurement" AV
Ance DPX400 "was used.

[IR] (see FIG. 1) 3360 cm ^-1 : OH (strong) 2950, 2910 cm ^-1 : methylene (strong) 1440 cm ^-1 : methylene (strong) 1240 cm ^-1 : methine (weak) 1144 cm ^-1 : crystal Band (between H and OH, strong
g) 1100 cm ^-1 : CO (medium) 850 cm ^-1 : methylene (medium) 660 cm ^-1 : OH (medium block)

[ ¹ H-NMR] (see FIG. 2) 1.376 to 1.538 ppm: methylene proton 3.528 ppm: methylene proton of primary methylol 3.849 ppm: methine proton 4.139 to 4.668 ppm: hydroxyl group

The copolymer before saponification and decarboxylation (A-
The assignment of the IR spectrum of B) was as follows. I
The R chart is shown in FIG.

[0058] [IR] (see FIG. 3) 2980,2940cm ^-1: methylene ^{(medium) 1810cm -1: C =} O (strong, carbonyl carbonate ^{group) 1740cm -1: C = O (} strong, residual acetic acid groups) 1438 cm ^-1 : methylene, 1379 cm ^-1 : CH ₃ COO 1240 cm ^-1 : methylene

The following evaluation was performed on the obtained polyvinyl alcohol. (Viscosity stability of aqueous solution) An 8% aqueous solution of polyvinyl alcohol was placed in a glass container, and the temperature of the aqueous solution was set to 20 ° C. Next, leave the glass container in a constant temperature water bath at 5 ° C,
The viscosities after standing for 1 hour and 24 hours were measured, and the thickening ratio was determined and evaluated as follows.・ ・ ・: Thickening ratio is less than 2.5 times. X: The thickening ratio is 2.5 times or more. The thickening ratio is calculated by the following equation. Thickening ratio = (viscosity after 24 hours at 5 ° C.) / (Viscosity after 1 hour at 5 ° C.)

(High-speed coating property) As a paper coating agent, 30 ° C.
Was used to measure the increase in viscosity of a 10% aqueous solution of polyvinyl alcohol under a high shear rate, and evaluated as follows. As a measuring device, a flow tester CFT-5 manufactured by Shimadzu Corporation was used.
00C was used.・ ・ ・: When the maximum value of the viscosity rise comes when the shear rate is 6 × 10 ⁶ / s or more ×: When the maximum value of the viscosity rise comes when the shear rate is less than 6 × 10 ⁶ / s

(Wood Adhesion Performance) The obtained polyvinyl alcohol was stirred and completely dissolved in distilled water at 80 ° C., and an aqueous solution having a concentration of about 15% was prepared. The aqueous polyvinyl alcohol solution was placed in a mold made of tetrafluoroethylene resin. And an isocyanate compound (MDI, isocyanate group content: 6.71 × 10 ⁻³ mol / g) as a crosslinking agent, to prepare an adhesive. The mixing ratio of the isocyanate compound and polyvinyl alcohol is such that the molar ratio of the isocyanate group and the hydroxyl group in the polyvinyl alcohol is (NCO / O
H) to give 0.2. The obtained adhesive was applied to an adherend (merkaba: average specific gravity 0.73, water content about 12).
%) So as to have an application amount of 220 g / m ^2, and after application, press-clamping at about 1 MPa at 20 ° C. × 1 day.
A heat treatment was performed at 2 ° C. for 2 hours, and a tensile test was performed at a crosshead speed of 10 mm / min as a single lap tensile shear type test piece. ○: Adhesive strength is 30 kgf / cm ² or more ×: Adhesive strength is less than 30 kgf / cm ²

(Water resistance of the film) The obtained polyvinyl alcohol was stirred and completely dissolved in distilled water at 80 ° C, and then an aqueous solution having a concentration of 9% was prepared. A cast film (100 μm × 1.5 cm × 4 cm) was prepared by mixing 10% with polyvinyl alcohol. The drying conditions after the casting were 25 ° C. × 4 days.
When the obtained film was immersed in 200 ml of hot water at 80 ° C. for 1 hour without stirring, the weight swelling ratio and the dissolution rate were calculated from the following formulas, and the water resistance was evaluated. The evaluation criteria are as follows.

Weight swelling ratio = weight of swollen film /
Absolute dry weight of swollen film Elution rate = [(absolute dry weight of film before immersion−absolute dry weight of swollen film) / absolute dry weight of film before immersion] ×
100 Here, the absolute dry weight of the swollen film is the weight when the film is immersed and then dried at 105 ° C. for 1 hour,
The absolute dry weight of the film before immersion is the weight when the film obtained above is dried at 105 ° C. for 5 minutes.

[Swelling magnification] ・ ・ ・: less than 3 times ・ ・ ・: less than 3 to 5 times ×: 5 times or more [elution rate (%)] ・ ・ ・: less than 5% ・ ・ ・: 5 to 5 Less than 10% ×: 10% or more

(Water solubility of film) A 10% aqueous solution of the obtained polyvinyl alcohol was prepared and cast on a hot roll at 60 ° C to prepare a film having a thickness of 30 µm. The film sample was cut into a square of 40 mm × 40 mm, which was sandwiched between slide mounts, immersed in water stirred at 20 ° C., and the time (number of seconds) until the film was completely dissolved was measured. We evaluated as follows. ○ ・ ・ ・ Within 40 seconds △ ・ ・ ・ Within 40 ~ 70 seconds × ・ ・ ・ Over 70 seconds

Example 2 A reaction vessel equipped with a reflux condenser, a dropping funnel and a stirrer was charged with 1300 g of vinyl acetate (A), 190 g of methanol, and vinyl ethylene carbonate (B) (R ¹ , R ² and R ³ were all used). 40.1 g (2.28 mol%) was charged, azobisisobutyronitrile was added at 0.06 mol% (based on the charged vinyl acetate monomer), and the temperature was increased under a nitrogen stream while stirring. The polymerization was started at 67 ° C., and at the same time, 10.17% of vinyl ethylene carbonate (B)
The methanol solution was charged according to the HANNA method, and 116 ml was charged until the polymerization rate reached 85.3%.

Incidentally, vinyl ethylene carbonate (B)
Is HAN so that it polymerizes uniformly with vinyl acetate (A).
The formula of NA [Reactivity ratio (r) of vinylethylene carbonate (B) = 5.4, reactivity ratio of vinyl acetate (A) (r)
= 0.85] was charged according to the polymerization rate. When the polymerization rate of vinyl acetate (A) reaches 85.3%, the polymerization is terminated. Subsequently, unreacted vinyl acetate monomer is removed from the system by a method of blowing methanol vapor to remove the copolymer (A). A methanol solution of -B) was obtained.

Next, the solution was diluted with methanol, adjusted to a concentration of 30%, and charged into a kneader.
While maintaining the temperature at 0 ° C, a 2% methanol solution of sodium hydroxide was added in an amount of 9 mmol% with respect to the vinyl acetate (A) unit in the copolymer (AB) to perform saponification and decarboxylation. . As the saponification and decarboxylation proceeded, the saponified product was precipitated, and finally became particulate. The produced polyvinyl alcohol was separated by filtration, washed well with methanol, and dried in a hot air drier to obtain an intended product.

The degree of saponification of the obtained polyvinyl alcohol was 99.6 mol% when analyzed by the amount of alkali consumed for hydrolysis of the remaining vinyl acetate units. The degree of polymerization was in accordance with JIS K 6726. The result of analysis was 1,360. The viscosity of a 4% aqueous solution of the polyvinyl alcohol was 18.5 mPa · s (20 ° C.) as measured by a Heppler viscometer, and the amount of modification was 3.1 mol% as calculated from NMR measurement. .

The IR spectrum, ¹ H-NMR (internal standard substance: tetramethylsilane, solvent: d6-DMSO) spectrum and ¹³ C-N of the obtained polyvinyl alcohol
MR (internal standard: 3- (Trimethylsilyl) propionic-2,
2,3,3-d ₄ acid, sodium salt, solvent: D ₂ O / H ₂ O = 1 /
1) The assignment of the spectrum was as follows. ¹³ CN
The MR chart is shown in FIGS. 4 and 5 (enlarged view).

[IR] A spectrum similar to that of FIG. 1 of Example 1 was obtained. [ ¹ H-NMR] A spectrum similar to that of FIG. 2 of Example 1 was obtained.

[ ¹³ C-NMR] (see FIGS. 4 and 5) 30.2 to 31.0 ppm: methylene carbon 37.0 to 37.2 ppm: methylene carbon 39.9 to 41.1 ppm: methylene carbon 46.2 ４７47.4 ppm: methylene carbon 66.3 to 66.7 ppm: primary carbon of methylol 67.8 to 68.1 ppm: methine carbon 69.0 to 69.6 ppm: methine carbon 70.5 to 77.2 ppm: methine carbon 77.1 to 77.4 ppm: methine carbon The same evaluation as in Example 1 was performed on the obtained polyvinyl alcohol.

Example 3 A reaction vessel equipped with a reflux condenser, a dropping funnel and a stirrer was charged with 1000 g of vinyl acetate (A), 500 g of methanol, 2,2
-Dimethyl-4-vinyl-1,3-dioxolane (C)
(R ¹ , R ² , and R ³ are all hydrogen, and R ⁴ and R ⁵ are all methyl groups.) 44.7 g (3 mol%) was charged,
Azobisisobutyronitrile was added in an amount of 0.065 mol% (based on the charged vinyl acetate monomer), and the temperature was increased under a nitrogen stream with stirring to carry out polymerization. The chain transfer constant of 2,2-dimethyl-4-vinyl-1,3-dioxolane (C) is 0.023. When the polymerization rate of vinyl acetate (A) reaches 84.7%, the polymerization is terminated, and then the unreacted vinyl acetate monomer is removed from the system by a method of blowing methanol vapor to remove the copolymer (A). A methanol solution of -C) was obtained.

Next, the solution was diluted with methanol, adjusted to a concentration of 30%, and charged into a kneader.
While maintaining the temperature at 0 ° C, saponification was performed by adding a 2% methanol solution of sodium hydroxide in an amount of 9 mmol% with respect to the vinyl acetate (A) unit in the copolymer (AC). As the saponification progressed, a saponified product was precipitated, and finally became a particulate form. The saponified product is dispersed in 3N hydrochloric acid (a mixed solvent of water / methanol = 1/1), deketalized at 60 ° C., the produced polyvinyl alcohol is separated by filtration, washed well with methanol, and dried with hot air. Dried in the machine,
The desired product was obtained.

The degree of saponification of the obtained polyvinyl alcohol was 99.2 mol% when analyzed by the amount of alkali consumed for hydrolysis of the remaining vinyl acetate units, and the degree of polymerization was in accordance with JIS K 6726. When the analysis was performed, it was 500. The viscosity of a 4% aqueous solution of the polyvinyl alcohol was 5.02 mPa · s (20 ° C.) as measured by a Heppler viscometer, and the amount of modification was 3.0 mol% as calculated from NMR measurement. .

The IR spectrum and ¹ H-NMR (internal standard substance: tetramethylsilane, solvent: d6-DMSO) spectrum of the obtained polyvinyl alcohol were assigned as follows.

[IR] A spectrum similar to that of FIG. 1 of Example 1 was obtained. [ ¹ H-NMR] A spectrum similar to that of FIG. 2 of Example 1 was obtained. The same evaluation as in Example 1 was performed for the obtained polyvinyl alcohol.

The IR of the copolymer (AC) before saponification was
The assignment of the spectrum, the IR spectrum of the saponified copolymer (AC) before deketalization, and the ¹ H-NMR (internal standard substance: tetramethylsilane, solvent: d-methanol) spectrum were as follows. . The copolymer (A-
FIG. 6 shows the IR chart of C), FIG. 7 shows the IR chart of the saponified copolymer (AC), and FIG. 8 shows the NMR chart.

[0079] [IR] (see FIG. 6) 2980,2940cm ^-1: methylene ^{(medium) 1740cm -1: C =} O (strong, residual acetate groups) 1438cm ^{-1: _{methylene, 1379cm -1: CH 3 COO 1240cm}} - ¹ : methylene

[IR] (see FIG. 7) 3360 cm ^-1 : OH (strong) 2950, 2910 cm ^-1 : methylene (strong) 1440 cm ^-1 : methylene (strong) 1240 cm ^-1 : methine (weak) 1144 cm ^-1 : crystal Band (between H and OH, strong
g) 1100 cm ^-1 : CO (medium) 850 cm ^-1 : methylene (medium) 660 cm ^-1 : OH (medium broad)

[ ¹ H-NMR] (refer to FIG. 8) 1.25 ppm: methyl proton (methyl of dimethyl ketal) 1.31 to 1.33 ppm: methyl proton (methyl of dimethyl ketal) 1.38 to 1. 66 ppm: methylene protons 1.87 to 1.99 ppm: methyl protons 3.84 to 3.91 ppm: methine protons 4.14 to 4.55 ppm: hydroxyl groups

The copolymer (AC) before deketalization
For the saponified product, the viscosity stability of the aqueous solution and the evaluation of the water solubility of the film were evaluated in the same manner as described above.

Example 4 A reaction vessel equipped with a reflux condenser, a dropping funnel and a stirrer was charged with 1000 g of vinyl acetate (A), 100 g of methanol,
-Dimethyl-4-vinyl-1,3-dioxolane (C)
(R ¹ , R ² , and R ³ are all hydrogen and R ⁴ and R ⁵ are all methyl groups.) 14.9 g (1 mol%) was charged.
Azobisisobutyronitrile was charged in an amount of 0.045 mol% (based on the charged vinyl acetate monomer), the temperature was increased under a nitrogen stream with stirring, and polymerization was started at 68 ° C. When the polymerization rate of vinyl acetate (A) reaches 90%, the polymerization is terminated, and then the unreacted vinyl acetate monomer is removed out of the system by a method of blowing methanol vapor to obtain a copolymer (AC). A) methanol solution was obtained.

Next, the solution was diluted with methanol, adjusted to a concentration of 30%, and charged into a kneader.
While maintaining the temperature at 0 ° C, saponification was performed by adding a 2% methanol solution of sodium hydroxide in an amount of 9 mmol% with respect to the vinyl acetate (A) unit in the copolymer (AC). As the saponification progressed, a saponified product was precipitated, and finally became a particulate form. The saponified product is dispersed in 3N hydrochloric acid (a mixed solvent of water / methanol = 1/1), deketalized at 60 ° C., the produced polyvinyl alcohol is separated by filtration, washed well with methanol, and dried with hot air. Dried in the machine,
The desired product was obtained.

The degree of saponification of the obtained polyvinyl alcohol was 99.3 mol% when analyzed by the amount of alkali consumed for hydrolysis of the remaining vinyl acetate units, and the degree of polymerization was in accordance with JIS K 6726. As a result of analysis, it was 1110. The viscosity of a 4% aqueous solution of the polyvinyl alcohol was 13 mPa · s (20 ° C.) as measured with a Höppler viscometer, and the modification amount was N
It was 0.9 mol% as calculated from MR measurement.

The assignment of IR spectrum and ¹ H-NMR (internal standard substance: tetramethylsilane, solvent: d6-DMSO) spectrum of the obtained polyvinyl alcohol was as follows.

[IR] A spectrum similar to that of FIG. 1 of Example 1 was obtained. [ ¹ H-NMR] A spectrum similar to that of FIG. 2 of Example 1 was obtained. The same evaluation as in Example 1 was performed for the obtained polyvinyl alcohol.

The copolymer (AC) before deketalization
The assignments of the IR spectrum and the ¹ H-NMR (internal standard substance: tetramethylsilane, solvent: d-methanol) spectrum of the saponified compound were as follows.

[IR] A spectrum similar to that of FIG. 7 of Example 3 was obtained. [ ¹ H-NMR] A spectrum similar to that of FIG. 8 of Example 3 was obtained. In addition, for the saponified copolymer (AC) before deketalization, the viscosity stability of the aqueous solution and the water solubility of the film were evaluated in the same manner as described above.

Example 5 A reaction vessel equipped with a reflux condenser, a dropping funnel and a stirrer was charged with 1300 g of vinyl acetate (A), 520 g of methanol, and 39.9 g (2 mol%) of glycerin monoallyl ether (D).
Was added, and 0.07 mol% of azobisisobutyronitrile (based on the charged vinyl acetate monomer) was added, and the temperature was increased under a nitrogen stream with stirring to carry out polymerization. Two hours after the initiation of the polymerization, 0.05 mol% of the polymerization initiator was added, 5.1 mol of the polymerization initiator was added after 5.1 hours, and 0.05 mol% was added after 6 hours. The chain transfer constant of glycerin monoallyl ether (D) is 0.017. When the polymerization rate of vinyl acetate (A) reaches 70%, the polymerization is terminated, and then the unreacted vinyl acetate monomer is removed from the system by blowing methanol vapor to remove the methanol solution of the copolymer. Obtained.

Next, the solution was diluted with methanol, adjusted to a concentration of 40%, and charged into a kneader.
While maintaining the temperature at ° C, saponification was performed by adding a 2% methanol solution of sodium hydroxide in an amount of 9 mmol% with respect to the vinyl acetate (A) unit in the copolymer. As the saponification progressed, a saponified product was precipitated, and finally became a particulate form.
The saponified product was separated by filtration, washed well with methanol, and dried in a hot-air drier to obtain an intended product.

The degree of saponification of the obtained polyvinyl alcohol was 99.2 mol% when analyzed by the amount of alkali consumed for hydrolysis of the remaining vinyl acetate units. The degree of polymerization was in accordance with JIS K 6726. As a result of analysis, it was 860. The viscosity of a 4% aqueous solution of the polyvinyl alcohol was 9.2 mPa · s (20 ° C.) as measured by a Höppler viscometer.
It was 1.7 mol% as calculated from MR measurement.

¹ H—N of the obtained polyvinyl alcohol
MR (solvent: d6-DMSO) spectrum and ¹³ C-N
The assignment and chart of MR are as follows. [ ¹ H-NMR] (see FIG. 9) 1.363 to 1.508 ppm: methylene proton 1.8 to 2.0 ppm: methyl proton of residual acetyl group 3.826 ppm: methine proton 3.98 to 4 ppm: 1,2 -Hydroxyl group derived from glycol 4.140 to 4.568 ppm: hydroxyl group

[ ¹³ C-NMR] (see FIG. 10) 43.995 to 45.2 ppm: methylene carbon 63.351 ppm: methylene carbon 70.916 ppm: primary carbon and secondary carbon of methylol 65.222 to 65.394 ppm : Methine carbon 65.567 to 66.886 ppm: methine carbon 68.277 ppm: methine carbon The obtained polyvinyl alcohol was evaluated in the same manner as in Example 1.

Example 6 In a reaction vessel equipped with a reflux condenser, a dropping funnel and a stirrer, 1200 g of vinyl acetate (A), 300 g of methanol, and 55.3 g (3 mol%) of glycerin monoallyl ether (D) were added.
Was added, azobisisobutyronitrile was added in an amount of 0.15 mol% (based on the charged vinyl acetate monomer), and the temperature was increased under a nitrogen stream with stirring to carry out polymerization. Two hours after the initiation of polymerization, 0.1 mol% of the polymerization initiator was added, 5.1 mol% was added after 5.1 hours, and 0.1 mol% was added after 6 hours. The chain transfer constant of glycerin monoallyl ether (D) is 0.017. When the polymerization rate of vinyl acetate (A) reaches 80%, the polymerization is terminated.
Unreacted vinyl acetate monomer was removed from the system by blowing methanol vapor to obtain a methanol solution of the copolymer.

Next, the solution was diluted with methanol, adjusted to a concentration of 40%, and charged into a kneader.
While maintaining the temperature at 0 ° C., saponification was performed by adding a 2% methanol solution of sodium hydroxide in an amount of 10 mmol% based on vinyl acetate (A) units in the copolymer. As the saponification progressed, a saponified product was precipitated, and finally became a particulate form. The saponified product was separated by filtration, washed well with methanol, and dried in a hot-air drier to obtain an intended product.

The degree of saponification of the obtained polyvinyl alcohol was 99.5 mol% when analyzed by the amount of alkali consumed for hydrolysis of the remaining vinyl acetate units. The degree of polymerization was in accordance with JIS K 6726. The result of analysis was 707. The viscosity of a 4% aqueous solution of the polyvinyl alcohol was 7.2 mPa · s (20 ° C.) as measured with a Heppler viscometer.
It was 2.7 mol% as calculated from MR measurement.

¹ H—N of the obtained polyvinyl alcohol
The assignment of each peak of MR and ¹³ C-NMR was the same as in Example 5. The same evaluation as in Example 1 was performed for the obtained polyvinyl alcohol.

Comparative Example 1 In Example 1, vinyl ethylene carbonate (B)
, But only vinyl acetate (A) is polymerized (S / M
= 0.5, S: methanol, M: vinyl acetate) and saponification was performed in the same manner to obtain polyvinyl alcohol. The degree of saponification of the obtained polyvinyl alcohol was 99.5 mol% when analyzed by the amount of alkali consumed for hydrolysis of the remaining vinyl acetate units. The degree of polymerization was analyzed according to JIS K 6726. When it went, it was 1200. The viscosity of the 4% aqueous solution of polyvinyl alcohol was 15 mPa · s (20 ° C.) as measured by a Heppler viscometer. The same evaluation as in Example 1 was performed for the obtained polyvinyl alcohol.

Table 1 shows the evaluation results of Examples 1 to 6 and Comparative Example 1.

[Table 1] High-speed of aqueous solution Viscosity stability of water-resistant film of wood adhesive film Coatability Performance Weight swelling ratio Elution rate Water-soluble example 1 ○ ○ ○ ○ ○ ○ ○ 〃 2 ○ ○ ○ ○ ○ ○ 〃 3 ○ ○ ○ ○ ○ ○ (○----○) ４ 4 ○ ○ ○ △ △ △ (○----○) ５ 5 ○ ○ ○ △ △ △ ６ 6 ○ ○ ○ ○ 比較 Comparative Example 1 × × × × × × Note) In Examples 3 and 4, () indicates the copolymer (AC) before deketalization. Only the viscosity stability of the aqueous solution and the water solubility of the film were evaluated.

Example 7 Polymerization and saponification were carried out in the same manner as in Example 2 to obtain a degree of polymerization of 12
50, polyvinyl alcohol having a 1,2-glycol modification amount of 6.6 mol% in the side chain and a saponification degree of 98.5 mol was obtained. The viscosity of the 4% aqueous solution of polyvinyl alcohol was measured by a Heppler viscometer, and was found to be 15.2 mPa ·
s (20 ° C.). 100 parts of the obtained 15% aqueous solution of polyvinyl alcohol was prepared, 15 parts of glycerin was added, and the mixture was cast on a hot roll at 70 ° C. to produce a film having a thickness of 50 μm, and the following evaluation was performed.

(Solubility in cold water) The film (3) was added to 1000 cc of water at 10 ° C. in a 1 liter beaker.
cm × 3 cm) and stirred with a stirrer (250 r
pm), the time (seconds) until complete dissolution was measured.

(Alkali Resistance) A 10 cm × 15 cm bag was heat-sealed using the obtained film.
30g of sodium carbonate in it, 40 ℃ x 85%
Leave for half a year under the condition of RH, then 3 cm from the bag
A piece of a 3 cm film was collected, immersed in 1000 cc of water at 15 ° C. according to the above, and the time (second) required for complete dissolution under stirring was measured.

(Chemical resistance) Using the obtained film,
Heat seal to make a bag of 10cm x 15cm, in which 30g of sodium dichloroisocyanurate is packaged,
After leaving for half a year under the condition of 40 ° C. × 85% RH, a 3 cm × 3 cm film piece is collected from the bag, immersed in 1000 cc of water at 15 ° C. according to the above, and completely dissolved under stirring. The time (sec) was measured.

Example 8 Polymerization and saponification were carried out in the same manner as in Example 2 to obtain a degree of polymerization of 130.
0, a polyvinyl alcohol having a 1,2-glycol modification amount of a side chain of 4.5 mol% and a saponification degree of 99.5 mol% was obtained. The viscosity of a 4% aqueous solution of the polyvinyl alcohol is
When measured by a Höppler viscometer, 16.8 mPa
S (20 ° C.). The same evaluation as in Example 7 was performed for the obtained polyvinyl alcohol.

Examples 9 and 10 The polyvinyl alcohols obtained in Examples 1 and 2 were evaluated in the same manner as in Example 7. In Example 9, the polyvinyl alcohol obtained in Example 1 was used.
In Example 10, the polyvinyl alcohol obtained in Example 2 was used.

Comparative Example 2 According to Comparative Example 1, unmodified polyvinyl alcohol having a degree of polymerization of 1400 and a degree of saponification of 88 mol% was obtained. The viscosity of the 4% aqueous solution of the polyvinyl alcohol was 15.5 mPa · s (20 ° C.) as measured with a Heppler viscometer. The same evaluation as in Example 7 was performed for the obtained polyvinyl alcohol.

Table 2 shows the evaluation results of Examples 7 to 10 and Comparative Example 2.

[Table 2] Cold water solubility (sec) Alkali resistance (sec) Chemical resistance (sec) Example 7 22 24 25 〃 8 25 27 28 ９ 9 31 38 38 ３１ 10 28 32 34 Comparative Example 2 72 280 Insoluble in water

[0111]

The novel vinyl alcohol resin (I) of the present invention contains 1,2-glycol in the side chain.
It shows a very excellent effect on the viscosity stability and water solubility of the aqueous solution, and has a high reactivity with a crosslinking agent and the like because of the presence of a hydroxyl group as a primary alcohol, so that a film having excellent water resistance can be obtained. is there. In addition, it has good coating properties without thickening even under high shear during high-speed coating, and also has excellent adhesion to an adherend. Further, a copolymer (AC) of a vinyl ester monomer (A) and 2,2-dialkyl-4-vinyl-1,3-dioxolane (C) represented by the general formula (3) is saponified. The novel vinyl alcohol-based resin (II) is useful as a precursor of the novel vinyl alcohol-based resin (I), has no unpleasant odor such as acetic acid odor, the viscosity stability of an aqueous solution, It shows an effect excellent in solubility. Further, the vinyl alcohol resin (I) or (II) of the present invention
Is effective for various uses, especially for adhesives, moldings, coatings, emulsifiers, suspending agents, etc. by utilizing its properties, and especially films made of vinyl alcohol resin (I) Is excellent in alkali resistance, acid resistance, etc., so even if alkaline and acidic substances are packaged for a long time, the solubility in cold water does not decrease, so it is also effective as a packaging film for various alkaline substances and various agricultural chemicals It is.

[0113]

[Brief description of the drawings]

FIG. 1 is an IR chart of the polyvinyl alcohol obtained in Example 1.

FIG. 2 shows a diagram of the polyvinyl alcohol obtained in Example 1.
It is a < ¹ > H-NMR chart.

FIG. 3 shows I of the copolymer (AB) obtained in Example 1.
It is an R chart.

FIG. 4 shows the relationship between the polyvinyl alcohol obtained in Example 2 and
It is a < ¹³ > C-NMR chart.

FIG. 5: Polyvinyl alcohol obtained in Example 2
FIG. 3 is a partially enlarged view of a ¹³ C-NMR chart.

FIG. 6 shows I of the copolymer (AC) obtained in Example 3.
It is an R chart.

FIG. 7 is an IR chart of a saponified copolymer (AC) (before deketalization) obtained in Example 3.

FIG. 8 is a ¹ H-NMR chart of a saponified copolymer (AC) (before deketalization) obtained in Example 3.

FIG. 9 shows the relationship between the polyvinyl alcohol obtained in Example 5 and
It is a < ¹ > H-NMR chart.

FIG. 10 is a ¹³ C-NMR chart of the polyvinyl alcohol obtained in Example 5.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09D 129/02 C09D 129/02 4J100 C09J 129/02 C09J 129/02 // C08L 29:04 C08L 29:04 SF term (reference) 3E086 AB01 AD01 AD13 BA02 BA15 BB72 CA29 CA35 4D077 AB14 AC01 BA07 CA11 DC19Z DC26Z DD03Y DD09Y DD13Y DE08Y 4F071 AA29 AF05 AH04 BA02 BB02 BC01 4J038 CE011 MA08 MA09 NA04 NA12 NA01 NA04 NA01 AE18Q AG02P AG03P AG04P AG05P AG08P AQ01Q BA03H BA03Q BC43P CA04 CA05 CA31 DA38 HA08 HA61 HB39 HE05 HE14 JA01 JA03 JA15 JA58 JA64 JA67

Claims (19)

[Claims] 1. A novel vinyl alcohol resin (I) containing a 1,2-glycol component in a side chain. 2. A novel vinyl alcohol-based resin (I) comprising a 1,2-glycol structural unit represented by the general formula (1). Embedded image However, R ¹ , R ² and R ³ are each independently hydrogen or an alkyl group. 3. A vinyl ester monomer (A) and a vinyl ethylene carbonate (B) represented by the general formula (2):
The novel vinyl alcohol resin (I) according to claim 1 or 2, wherein the copolymer (A-B) is saponified and decarboxylated. Embedded image However, R ¹ , R ² and R ³ are each independently hydrogen or an alkyl group. 4. A vinyl ester monomer (A) and a vinyl ethylene carbonate (B) represented by the general formula (2):
4. The novel vinyl alcohol resin (I) according to claim 3, wherein the copolymer (A-B) is copolymerized based on the HANNA method. 5. The novel vinyl alcohol resin according to claim 3, wherein the content of the vinyl ethylene carbonate (B) represented by the general formula (2) is 0.1 to 20 mol%. I). 6. A vinyl ester monomer (A) and 2,2-dialkyl-4-vinyl- represented by the general formula (3).
A novel vinyl alcohol resin (II) obtained by saponifying a copolymer (AC) with 1,3-dioxolane (C). Embedded image However, R ¹ , R ² , R ³ , R ⁴ and R ⁵ are each independently hydrogen or an alkyl group. 7. The method according to claim 1, wherein the content of 2,2-dialkyl-4-vinyl-1,3-dioxolan (C) represented by the general formula (3) is 0.1 to 20 mol%. Item 6. A novel vinyl alcohol resin (II) according to Item 6. 8. A vinyl ester monomer (A) and 2,2-dialkyl-4-vinyl- represented by the general formula (3).
The novel vinyl alcohol resin (I) according to claim 1 or 2, wherein the copolymer (AC) with 1,3-dioxolane (C) is saponified and deketalized. 9. The method according to claim 1, wherein the content of 2,2-dialkyl-4-vinyl-1,3-dioxolane (C) represented by the general formula (3) is 0.1 to 20 mol%. Item 8. The novel vinyl alcohol resin (I) according to Item 8. 10. A copolymer of a vinyl ester monomer (A) and glycerin monoallyl ether (D) (A-
The novel vinyl alcohol resin (I) according to claim 1 or 2, which is obtained by saponifying D). 11. The novel vinyl alcohol resin (I) according to claim 10, wherein the content of glycerin monoallyl ether is 0.1 to 20 mol%. 12. An adhesive using the novel vinyl alcohol-based resin (I) or (II) according to claim 1. 13. A molded article characterized by using the novel vinyl alcohol resin (I) or (II) according to claim 1. 14. The molded article according to claim 13, which is a water-soluble film for packaging an article selected from pesticides, detergents, laundry clothes, civil engineering additives, bactericides, dyes and pigments. 15. A water-soluble film for packaging an alkaline substance using a novel vinyl alcohol resin (I) or (II) having a saponification degree of 98.1 mol% or more. Moldings. 16. A water-soluble film for packaging agricultural chemicals, which uses a novel vinyl alcohol resin (I) or (II) having a saponification degree of 98.1 mol% or more. Moldings. 17. A coating comprising the novel vinyl alcohol-based resin (I) or (II) according to any one of claims 1 to 11. 18. An emulsifier using the novel vinyl alcohol resin (I) or (II) according to claim 1. 19. A suspending agent comprising the novel vinyl alcohol resin (I) or (II) according to any one of claims 1 to 11.