JPH09110926A - Carbonic-esterified polyvinyl alcohol derivative and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a novel carbonic-esterified polyvinyl alcohol deriv. having specific kinds of repeating units by subjecting polyvinyl alcohol and a diaryl carbonate to transesterification. SOLUTION: This polyvinyl alcohol deriv. comprises repeating cyclic carbonic ester units represented by formula I [wherein (a) is the molar fraction of the structure comprising the repeating units based on the deriv.; the same applies hereunder], repeating polyvinyl alcohol units represented by formula II [wherein (b) is the molar fraction], repeating polyvinyl acetate units represented by formula III [wherein (c) is the molar fraction. being 0-0.3]. and repeating monocarbonic ester units represented by formula IV [wherein R1 is H or a 1-4C group; and (d) is the molar fraction] and/or repeating cross-linked carbonic ester units represented by formula V [wherein (e) is the molar fraction], subject to the condition that the molar fractions, (a) to (e), satisfy at the same time the relations represented by formulas VI and VII.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel carbonic acid esterified polyvinyl alcohol derivative obtained by a carbonic acid esterification reaction of polyvinyl alcohol (hereinafter referred to as "carbonic acid esterified PVA derivative") and a method for producing the same. More specifically, a polymer produced by a transesterification reaction of polyvinyl alcohol and a diaryl carbonate represented by the general formula (VI), that is, a cyclic carbonic acid ester structure composed of the repeating unit represented by the general formula (I), A polyvinyl alcohol structure comprising a repeating unit represented by the general formula (II) and a polyvinyl acetate structure comprising a repeating unit represented by the general formula (III), and a repeating unit represented by the general formula (IV) In the presence or absence of a carbonic acid esterified PVA derivative containing a monocarbonic acid ester structure composed of units and / or a crosslinked carbonic acid ester structure composed of repeating units represented by the general formula (V), and an esterification reaction catalyst In the reaction solvent, the melting point of the reaction solvent or higher and the boiling point of the reaction solvent or 200 The present invention relates to a method for producing a carbonate esterified PVA derivative, which comprises reacting polyvinyl alcohol with a diaryl carbonate in a temperature range lower than the lower one of ° C.

The carbonate esterified PVA derivative of the present invention is
Physical and chemical properties differ depending on the degree of carbonic acid esterification and the composition ratio of hydroxyl groups and acetyl groups, and the degree of carbonic acid esterification is low. It can be used in the field of application as polyvinyl alcohol itself, such as textile processing agents for textiles and textile processing, paper processing agents, emulsion stabilizers, adhesives, binders, films and the like.
On the other hand, the degree of carbonic acid esterification is increased, and it has excellent toughness, flexibility, flexibility, heat resistance, adhesiveness, dispersibility, water resistance, oil resistance, solubility in organic solvents, transparency, etc.
Various resins such as phenol resin, epoxy resin, urethane resin, urea resin, alkyd resin, melamine resin, natural resin and plastic such as triethylene glycol, tricresyl phosphate, dibutyl phthalate, dibutyl sebacate, methyl acetyl ricinoleate and castor oil. Those having excellent compatibility with the agent are, by themselves, or mixed with the other compatible resin or plasticizer, and are used as wash primers, powder coatings, metal coatings, metal foil coatings, metal inks, Application to paints such as vacuum deposition paints, glossy surface protection paints, waterproof paints, wood paints, leather paints, concrete paints, adhesion to printed circuit boards, adhesion of enamel electric wires for coils, adhesion of metals, heat seal adhesives , Pressure sensitive adhesive, film adhesive, electrodeposited flocking adhesive, leather adhesive, etc. , IC ceramic binder, magnetic tape binders, electrostatic copier toners, reflective sheet binder, brake lining binders, such as nonwoven binders, etc. Application to various binders may be used for a wide range of fields.

[0003]

2. Description of the Related Art Conventionally, many studies have been reported on ester compounds of polyvinyl alcohol (PVA) which is a synthetic polymer. However, most of these studies are synthetic reactions by addition polymerization or cyclopolymerization from a vinyl monomer corresponding to the basic structure of the PVA ester to be produced, and the chemical reaction of the polymer itself utilizing the hydroxyl group of PVA. When it comes to esterification research, the number is not large. So far, PV
The research by A's own esterification reaction has been studied as a research object of a chemical reaction of a polymer alcohol or for the purpose of improving the properties of PVA.

However, the esterification of PVA by the reaction of PVA itself makes it possible to synthesize a PVA ester which cannot be synthesized from a monomer, and the PVA is made highly functional.
It is considered to be an important reaction in the sense of improving performance and finding new uses for PVA.
The acetalization reaction of A is a very important reaction in terms of industrial use of PVA. Since PVA is insolubilized in water due to acetalization, PVA is used as a fiber or as an industrial material in various industrial fields. Has reached the end. As an example of such a report, Japanese Patent Laid-Open No. 53-
In JP-A-143691, JP-A-54-20073, JP-A-54-118490, etc., a modified polyvinyl alcohol-based polymer whose side chain is modified with a cyclic acid anhydride is water-soluble depending on its production conditions. It is disclosed that it can be a polymer having various properties ranging from a polymer to a water-insoluble water-absorbing polymer. Further, JP-B-63-58868 discloses that the modified polyvinyl alcohol-based polymer is suitable. By applying a solution prepared by dissolving in a different solvent to various base materials, or after mixing with various base materials, by heat treating the base material subjected to the treatment,
It is disclosed to obtain a coating material having excellent water absorption or hygroscopicity. Further, in JP-B-60-8043 and JP-B-60-8044, an unsaturated carboxylic acid compound is added to an aqueous PVA solution or a polar organic solvent solution of PVA to carry out an esterification reaction, and then an aldehyde compound is added. PV by acetalization reaction
A method of producing polyvinyl acetal useful as an adhesive, a paint, etc. by modifying A has been proposed. Furthermore, JP-B-4-28001 discloses that a photopolymerizable or photocrosslinkable mixed composition is constituted by esterifying PVA with an activated carboxylic acid derivative in the presence of a tertiary amine. A method for producing an acylated polyvinyl alcohol used is disclosed in Japanese Patent Publication No. 6-41520, in which a polyvinyl alcohol grafted three with enhanced waterproofness by a ring-opening esterification reaction of PVA and an acrylate / maleic anhydride copolymer. Original copolymers are each disclosed. Thus, in the esterification reaction of PVA itself, by utilizing the reactivity of the hydroxyl group, a new functional group is introduced into the side chain and PVA has a new function.
The expression of properties is considered to be an important and effective method.

On the other hand, as a study of esterification utilizing the reactivity of the hydroxyl group of the hydroxyl group-containing compound, attempts have been made to esterify a hydroxy compound (alcohol) with a carbonic acid diester, for example, JP-A-5-1250.
No. 21 proposes a method for producing a carbonate by subjecting a hydroxy compound such as an aliphatic alcohol, an alicyclic alcohol, or an aromatic alcohol to a transesterification reaction with dimethyl carbonate in the presence of a transesterification catalyst. . And, in particular, US Pat. No. 5,091,543 discloses alkyl ammonium salts, pyridinium salts,
1,2-diols or 1,3-diols are carbonated in the presence of a catalyst selected from a strong amine or a weak base ion exchange resin containing a tertiary amine and an alkylammonium group or a tertiary amino group. A method for producing a 5- or 6-membered cyclic carbonate, monocarbonate and carbonic acid diester by reacting with a carbonic acid diester such as dimethyl, diethyl carbonate and diphenyl carbonate while distilling and removing an alcohol or a phenolic compound as a by-product. Is disclosed.

Therefore, if the reaction of such a diol with a carbonic acid diester can be applied not only to a monomer but also to a polymer, it is considered possible to synthesize a polymer ester having a carbonic acid ester having a cyclic structure in the polymer. As such a polymer ester, a polymer containing a 6-membered cyclic carbonate structure and a 5-membered cyclic carbonate structure simultaneously obtained by polymerization of divinyl carbonate is already known (Bull. Che.
m. Soc. Japan, 38 (11), 1905 (1965), etc.). However, there have been no research reports on the reaction between a polymer having a hydroxyl group and a carbonic acid diester, particularly a carbonic acid esterification reaction of PVA with a carbonic acid diester as an example of the synthesis of a PVA ester that cannot be synthesized by polymerizing monomers. Of.

[0007]

The object of the present invention is to provide various physical and chemical properties from a water-soluble polymer to a water-insoluble polymer by a carbonic acid esterification reaction of polyvinyl alcohol with a diaryl carbonate. Obtained as a polymer, a fiber processing agent, a paper processing agent, an emulsion stabilizer,
In addition to applications as water-soluble polyvinyl alcohol such as adhesives, binders, films, etc., as a water-insoluble polymer, by itself, or by mixing with other resins or plasticizers compatible with it, paints, It is an object of the present invention to provide a novel carbonic acid esterified PVA derivative useful for application to adhesives, binders, etc., which cannot be synthesized from the corresponding monomer, and a method for producing the same.

[0008]

[Means for Solving the Problems] The inventors of the present invention have utilized the esterification reaction, which is one of the chemical reactions of the hydroxyl groups of polyvinyl alcohol, to synthesize a novel ester derivative of polyvinyl alcohol by the reaction of polyvinyl alcohol itself. As a result of repeated intensive studies, in the presence or absence of a base catalyst for an esterification reaction such as an alkylammonium salt, in an aprotic polar solvent of polyvinyl alcohol (such as dimethyl sulfoxide), the melting point of the solvent or more, In addition, by carrying out the esterification reaction of polyvinyl alcohol with the diaryl carbonate within a temperature range of boiling point or 200 ° C., whichever is lower, various differences from a water-soluble polymer to a water-insoluble polymer are obtained. With physical and chemical properties, and therefore fiber processing , A novel carbonate esterified PVA derivative that can be used in a wide range of fields such as paper processing agents, paints, adhesives and binders (that is, containing a cyclic carbonate structure, a polyvinyl alcohol structure and a polyvinyl acetate structure, and a monocarbonate ester) It was found that a polymer comprising a structure and / or a crosslinked carbonic acid ester structure) was obtained, and the present invention was completed.

That is, the first invention according to claim 1 is the carbonic esterified PV of the general formula (I) (wherein a is a structure consisting of the repeating unit represented by the formula).
A cyclic carbonic acid ester structure composed of repeating units represented by A derivative) and the general formula (II) (wherein, b is a structure of repeating units represented by the formula) A polyvinyl alcohol structure comprising a repeating unit represented by an esterified PVA derivative) and the general formula (III) (wherein c is a structure comprising a repeating unit represented by the formula, A polyvinyl acetate structure comprising a repeating unit represented by a molar fraction in the carbonic acid esterified PVA derivative, which is a value in the range of 0 to 0.3), and
The general formula (IV) (wherein, R ₁ represents a hydrogen atom, or an alkyl group or an alkoxy group having 1 to 4 carbon atoms, and d is a structure of a repeating unit represented by the formula. , A monocarbonate structure comprising a repeating unit represented by a carbonic acid esterified PVA derivative) and / or the general formula (V) (wherein e is a repeating unit represented by the formula). Containing a cross-linked carbonic acid ester structure consisting of repeating units represented by a repeating unit represented by a structure consisting of units in a carbonic acid esterified PVA derivative, and further, the values of a to e are in the formula (I) (where Where a, b, d and e
Represents the same meaning as a, b, d and e in the general formulas (I), (II), (IV) and (V) respectively and the above formula (II) (wherein a to e are represented). Can have the same meanings as a to e in the above general formulas (I) to (V) at the same time, and can be achieved by providing a carbonate esterified PVA derivative.

A second invention according to claim 2 is polyvinyl alcohol and the general formula (VI) (wherein R is
₁ has the same meaning as R ₁ in the above general formula (IV), and R ₂ represents a hydrogen atom or an alkyl group or an alkoxy group having 1 to 4 carbon atoms. In addition,
R ₁ and R ₂ may be the same or different) and a diaryl carbonate represented by the formula (1) is reacted to provide a method for producing a carbonic acid esterified PVA derivative according to the first invention. it can. A third invention according to claim 3 is, in a reaction solvent, in the presence or absence of an esterification reaction catalyst, at least the melting point of the reaction solvent, and the boiling point of the reaction solvent or 200 ° C. It can be achieved by providing a method for producing a carbonate esterified PVA derivative according to the second invention, characterized in that polyvinyl alcohol and the diaryl carbonate are reacted in a temperature range lower than or equal to the lower temperature.

Further, a fourth invention according to claim 4 is the method for producing a carbonate esterified PVA derivative according to the third invention, characterized in that the reaction solvent is an aprotic polar solvent. According to a fifth aspect of the present invention, in the ion exchange, the esterification reaction catalyst contains an alkyl ammonium salt, a pyridinium salt, a diazabicycloalkene, a tertiary amine, an alkyl ammonium group or a tertiary amino group. 7. A method for producing a carbonic acid esterified PVA derivative according to the third or fourth invention, which is a base catalyst selected from the group consisting of a resin and an alkaline catalyst, and the sixth method according to claim 6. In the invention, the carbonic acid esterified PVA derivative according to any one of the second to fifth inventions is characterized in that the diaryl carbonate is diphenyl carbonate. Law, can be achieved by providing, respectively.

The present invention will be described in detail below. The carbonic acid esterified PVA derivative of the present invention is a novel polymer obtained by subjecting polyvinyl alcohol to a carbonic acid esterification reaction with a diaryl carbonate described below by a method described below. That is, the polymer is a repeating unit represented by the above general formula (I) (wherein a represents a mole fraction in the carbonic acid esterified PVA derivative of the structure consisting of the repeating unit represented by the formula). And a general formula (II) (wherein, b represents a mole fraction of the structure consisting of the repeating unit represented by the formula in the carbonic acid esterified PVA derivative). And a polyvinyl alcohol structure comprising a repeating unit, and the general formula (III) (wherein c is
The molar fraction of the structure composed of the repeating unit represented by the formula in the carbonic acid esterified PVA derivative is shown as 0 to
And a polyvinyl acetate structure comprising a repeating unit represented by the formula (IV), wherein R ₁ is a hydrogen atom or 1
To d represent an alkyl group or an alkoxy group having 4 carbon atoms, and d represents a repeating unit represented by the formula, which represents a mole fraction in the carbonic acid esterified PVA derivative). And / or the general formula (V)
(In the formula, e represents a mole fraction of the structure consisting of the repeating unit represented by the formula in the carbonic acid esterified PVA derivative), and contains a crosslinked carbonate structure consisting of the repeating unit. The values of a to e are the same as those in the formula (I) (where a, b, d and e are respectively a, b in the general formulas (I), (II), (IV) and (V)). , D and e) and the above formula (II) (wherein a to e respectively have the same meanings as a to e in the general formulas (I) to (V)) at the same time. It is a carbonated PVA derivative characterized by satisfying. Therefore, the chemical structure of the polymer is represented by the following general formula (VII)

[0013]

Embedded image (In the formula, a to e are respectively represented by the general formula (I).
Has the same meaning as a to e in (V), and a
Is 0.003 to 0.408, and d and e are 0 to
The value is in the range of 0.816, and 0 <(2a + d
+ E) / (2a + b + d + e) ≦ 0.816, and
2a + b + c + d + e = 1.0 at the same time).

Since polyvinyl alcohol is produced exclusively by hydrolysis (saponification) of polyvinyl acetate, as will be described later, the polyvinyl acetate monomer represented by the general formula (III) is contained in the polyvinyl alcohol. A polyvinyl acetate structure consisting of repeating structural units remains. Since this polyvinyl acetate structure does not change during the carbonic acid esterification reaction of the polyvinyl alcohol and the diaryl carbonate of the present invention, the composition ratio of the polyvinyl acetate structure in the carbonic acid esterified PVA derivative is Is equal to the composition ratio of. Then, the composition ratio of the polyvinyl acetate structure in the polyvinyl alcohol, the degree of saponification when producing the raw material polyvinyl alcohol of the present invention from polyvinyl acetate,
That is, it depends on the saponification degree of polyvinyl alcohol. In the present invention, as described below, the saponification degree of the raw material polyvinyl alcohol is 70 to 100 mol%, that is, the composition ratio of the polyvinyl acetate structure in the raw material polyvinyl alcohol is 0 to 30 mol%, and therefore, The mole fraction (c) of the polyvinyl acetate structure comprising the repeating unit represented by the general formula (III) in the carbonic acid esterified PVA derivative can take a value in the range of 0 to 0.3.

The carbonic acid esterification reaction of the present invention is a dephenolic compound reaction between a hydroxyl group having a polyvinyl alcohol structure consisting of repeating vinyl alcohol monomer structural units in the raw material polyvinyl alcohol and a diaryl carbonate described below, that is, It is based on a bifunctional transesterification reaction of polyvinyl alcohol with diaryl carbonate, and the polyvinyl alcohol structure in the raw material polyvinyl alcohol is composed of the repeating unit represented by the general formula (I) by the carbonic esterification reaction. A cyclic carbonic acid ester structure, or in addition to the structure, a monocarbonic acid ester structure composed of the repeating unit represented by the general formula (IV) and / or a crosslinked carbonic acid ester composed of the repeating unit represented by the general formula (V). The structure is modified. Therefore, the amount of modification is
2 times the molar fraction (a) of the cyclic carbonic acid ester structure consisting of the repeating unit represented by the general formula (I) in the VA derivative (the repeating unit represented by the general formula (I) constituting the cyclic carbonic acid ester structure). Is equal to (because it is generated from 2 repeating structural units of the vinyl alcohol monomer constituting the polyvinyl alcohol structure), or this value and the above formula (IV) in the carbonate esterified PVA derivative. And a mole fraction (d) of a monocarbonic acid ester structure consisting of repeating units, and a mole fraction (e) of a crosslinked carbonic acid ester structure consisting of repeating units represented by the general formula (V) in the carbonic acid esterified PVA derivative. Equal to (2a + d + e). Further, the molar fraction (b ₀ ) of the polyvinyl alcohol structure composed of vinyl alcohol monomer repeating structural units in the raw material polyvinyl alcohol is calculated by the value of 2a and the general formula (II) in the carbonate esterified PVA derivative. The sum of the values of the mole fraction (b) of the polyvinyl alcohol structure consisting of the repeating units shown, that is, equal to (2a + b), or the value of 2a, the value of d, and the value of e, Sum with the value of b, that is, (2a + b +
equal to d + e). Therefore, the carbonic acid esterification degree (mol%) of the raw material polyvinyl alcohol, that is, the modification rate (mol%) is {2a / (2a + b)} × 100 or {(2a + d + e) / (2a + b + d + e)} × 100.
Is obtained as the value of By the way, it is not possible to completely carbonate the polyvinyl alcohol structure consisting of the vinyl alcohol monomer repeating structural unit in polyvinyl alcohol, and in the carbonic acid esterification reaction as well as in the case of acetalization of polyvinyl alcohol with an aldehyde compound. Similarly, the theory of Flory is assumed to be valid, and the theoretical maximum carbonation degree is 81.6.
It is said to be mol%.

Therefore, the minimum value of the carbonic acid esterification degree desired in the present invention is 1 mol%, as will be described later, but when carrying out the carbonic acid esterification reaction of polyvinyl alcohol with this value as a target, The production amount of the cyclic carbonic acid ester structure composed of the repeating unit represented by the general formula (I) is minimized, and the value of a is the minimum value of 0.003. In the carbonic acid esterification reaction of polyvinyl alcohol, the monocarbonic acid ester structure composed of the repeating unit represented by the general formula (IV) and the crosslinked carbonic acid ester structure composed of the repeating unit represented by the general formula (V) are respectively formed. When not generated, the values of d and e have a minimum value of 0. On the other hand, in the carbonic acid esterification reaction of the polyvinyl alcohol, the saponification degree is 100 mol%.
Of polyvinyl alcohol as a raw material, only the cyclic carbonic acid ester structure composed of the repeating unit represented by the general formula (I), or only the monocarbonic acid ester structure composed of the repeating unit represented by the general formula (IV), or When only the cross-linked carbonic acid ester structure composed of the repeating unit represented by the general formula (V) is produced with the above-mentioned theoretical maximum carbonic acid esterification degree, a, d and e have the maximum values. is there.

That is, the value of a is 0.003 to
The value of d and e varies within the range of 0.408.
It fluctuates within the range of up to 0.816. In this case, the values of d and e are 0, that is, the general formula (I
V) when a monocarbonic acid ester structure consisting of the repeating unit and a crosslinked carbonic acid ester structure consisting of the repeating unit represented by the general formula (V) is not formed, or when at least one of the values of d and e is When it takes a value within the above range other than 0, that is, a monocarbonate structure consisting of the repeating unit represented by the general formula (IV) and / or a crosslinked carbonate consisting of the repeating unit represented by the general formula (V). When the structure is generated, the a,
The values of b, d and e satisfy the above mathematical formula (I) indicating the degree of carbonic acid esterification in the carbonic acid esterification reaction of the polyvinyl alcohol of the present invention, that is, the modification rate of the polyvinyl alcohol structure in the polyvinyl alcohol by the reaction. Must. Further, the values of a to e are
Since it represents the mole fraction of the structural component composed of each repeating unit constituting the carbonic acid esterified PVA derivative of the present invention, the above formula (II) must also be satisfied.

In the present invention, the cyclic carbonic acid ester structure, monocarbonic acid ester structure in the carbonic acid esterified PVA derivative having the chemical structure represented by the general formula (VII),
The composition ratios of the cross-linked carbonic acid ester structure, the polyvinyl alcohol structure and the polyvinyl acetate structure are not particularly limited, and can be freely selected within a range in which the values of a to e satisfy the above ranges. However, the composition ratio of the cyclic carbonic acid ester structure, the monocarbonic acid ester structure, and the crosslinked carbonic acid ester structure in the carbonic acid esterified PVA derivative is such that the carbonic acid ester of the raw material polyvinyl alcohol in the carbonic acid esterification reaction of the polyvinyl alcohol with the diaryl carbonate. It is related to the degree of acidification, and generally, the lower the degree of carbonic acid esterification (that is, the less progress of the carbonic acid esterification reaction), the higher the composition ratio of the monocarbonic acid ester structure. It is said that the composition ratio of the cyclic carbonic acid ester structure tends to increase as the carbonic acid esterification degree increases (that is, the carbonic acid esterification reaction progresses more). Further, it is said that as the degree of carbonic acid esterification further increases (that is, the carbonic acid esterification reaction further proceeds), the composition ratio of the crosslinked carbonic acid ester structure increases. The target product in the carbonic acid esterification reaction of the present invention is a cyclic carbonic acid ester structure composed of the repeating unit represented by the general formula (I), and a monocarbonic acid ester structure composed of the repeating unit represented by the general formula (IV). The cross-linked carbonic acid ester structure composed of the repeating unit represented by the general formula (V) is a rather undesirable by-product. Therefore, in the present invention,
In the carbonic acid esterification reaction of the polyvinyl alcohol with the diaryl carbonate, the repeating unit represented by the general formula (I) in the carbonic acid esterified PVA derivative obtained by appropriately selecting the carbonic acid esterification degree of the raw material polyvinyl alcohol The composition ratio of the cyclic carbonic acid ester structure consisting of, the monocarbonic acid ester structure consisting of the repeating unit represented by the general formula (IV) and the cross-linked carbonic acid ester structure consisting of the repeating unit represented by the general formula (V), that is, the above a The values of ~ e can be appropriately selected according to the purpose.

As the carbonic acid esterified PVA derivative, the difference in the carbonic acid esterification degree and the composition ratio of the hydroxyl group and the acetyl group, that is, the values of a to e in the general formula (VII) showing the chemical structure of the polymer, In other words, the cyclic carbonic acid ester structure composed of the repeating unit represented by the general formula (I), the monocarbonic acid ester structure composed of the repeating unit represented by the general formula (IV), and the general formula (V)
In the polymer having a cross-linked carbonic acid ester structure composed of the repeating unit represented by, a polyvinyl alcohol structure composed of the repeating unit represented by the general formula (II) and a polyvinyl acetate structure composed of the repeating unit represented by the general formula (III). Due to the difference in the composition ratio in (2), a polymer having various different physical and chemical properties from a water-soluble polymer to a water-insoluble polymer can be obtained.

For example, in the present invention, the carbonic acid esterified PVA derivative having no crosslinked carbonic acid ester structure consisting of the repeating unit represented by the general formula (V) has a degree of polymerization of 200 to 5,000 and a specific gravity (n-hexane as a medium). Is 1.20 to 1.40, the glass transition temperature (measured by the DSC method) is 60 to 90 ° C., and the melting point (D
(Measured by SC method) is 200 to 240 ° C, and tensile yield point strength (measured in accordance with ASTM D638) is 100 to 5
00 kgf / cm ² , tensile breaking strength (ASTM D63
8) is 100 to 700 kgf / cm ² ,
Also, the tensile elongation at break (measured according to ASTM D638) is preferably 50 to 400%.

On the other hand, when the carbonic acid esterified PVA derivative has a crosslinked carbonic acid ester structure composed of the repeating unit represented by the general formula (V), the carbonic acid esterified PVA derivative is intermolecularly crosslinked.
The degree of polymerization is infinite.

Further, regarding the solubility of the carbonic acid esterified PVA derivative of the present invention in water at room temperature, the following formula (III)

[0023]

(Equation 3)

Different properties are exhibited depending on the degree of carbonic acid esterification of the carbonic acid esterified PVA derivative represented by. That is, the carbonic acid esterified PVA derivative is soluble in water up to a carbonic acid esterification degree of about 13 mol%, but partially swells in water in the range of about 13 to 35 mol%. When it exceeds 35 mol%, it becomes almost completely insoluble. Therefore, carbonated PV
As the use of the A derivative, the above-described fiber processing agent, paper processing agent, emulsion stabilizer, adhesive, binder, film, etc.
To leave the field of application as polyvinyl alcohol, a water-soluble polymer, the carbonated PVA derivative should be at least water soluble and have a low degree of modification with a degree of carbonation of about 13 mol% or less. It is preferable. Further, in consideration of application to paints, adhesives, binders, etc. by mixing with other thermosetting resins or plasticizers which are compatible with the carbonate esterified PVA derivative, the carbonate esterified PVA derivative is Considering the reaction between the residual hydroxyl group due to the polyvinyl alcohol structure and the thermosetting resin or the plasticizer, it should be limited to a water-soluble one or one that swells in water at best and has a carbonic acid esterification degree of 35. It is preferably not more than mol%. On the other hand, polyvinyl alcohol is largely modified by carbonic acid esterification, and its polar carbonate group (-O
Utilizing the excellent adhesiveness and adhesion of COO-),
When it is intended to be applied to paints, adhesives, binders, etc. by itself, the carbonic acid esterified PVA derivative has a high modification rate such that the carbonic acid esterification degree exceeds 35 mol%, that is, a water-insoluble region. It is preferable that

Further, the carbonic acid esterified PVA derivative of the present invention has the following characteristics as its solubility in an organic solvent. For example, in the case of dimethyl sulfoxide, when the carbonic acid esterification degree is 65 mol% or less, it is soluble in the solvent, but when it exceeds about 65 mol%,
It may be partially dissolved in the solvent, probably because of the gelation due to the formation of the crosslinked carbonic acid ester structure composed of the repeating unit represented by the general formula (V), that is, the formation of the intermolecular crosslink bond. On the other hand, it is insoluble in tetrahydrofuran in all regions of the carbonic acid esterification degree desired in the present invention. Further, in the case of formic acid, it is soluble in the solvent when the carbonic acid esterification degree is about 10 mol% or less, but becomes swelled in the range of about 10 to about 50 mol%, and about 50 to about 65 mol. %, It becomes soluble again, and in the range of more than about 65 mol%, as in the case of the above-mentioned dimethyl sulfoxide, it may be a partially dissolved state due to gelation due to the formation of intermolecular cross-linking bonds. It shows a unique property.

Furthermore, the carbonated PV of the present invention
As the chemical properties of the A derivative, it is possible to cite the property of being resistant to an acid such as not being hydrolyzed by an aqueous formic acid solution or an aqueous hydrochloric acid solution. On the other hand, it has the drawback of being weak against alkali, such as being easily hydrolyzed by an aqueous solution of sodium hydroxide or potassium hydroxide,
It can be said that it is more resistant to alkali hydrolysis than a polyester resin obtained by an esterification reaction by polycondensation of a polybasic acid and a polyhydric alcohol and having a use as a paint or an adhesive.

As described above, the present invention, from water-soluble ones to water-insoluble ones, has a purpose (use) for its use.
According to the above, carbonic acid esterified PVA derivatives having various different physical and chemical substances are targeted.

Next, a method for producing the carbonic acid esterified PVA derivative of the present invention will be described. In the present invention, the polyvinyl alcohol used as a raw material is a vinyl monomer that repeats the polymer main chain, that is, —CH ₂ CH (O
H) -is a generic term for water-soluble or at least water-dispersible polymers having a structural unit. Polyvinyl alcohol is currently industrially produced mainly by hydrolyzing (saponifying) a polymer of vinyl acetate. From this fact, it can be said that polyvinyl alcohol is generally a hydrolyzate of polyvinyl acetate (saponified product). ) Can be said. A number of brands having different degrees of polymerization and degrees of hydrolysis (degrees of saponification) are commercially available. In the present invention, it is not particularly limited as long as it has a property as polyvinyl alcohol, and all commercially available brands can be used, but the average degree of polymerization is in the range of 200 to 5,000. Therefore, polyvinyl alcohol having a saponification degree of 70 to 100 mol% can be preferably used. Further, the form is preferably powdery. Therefore, the polyvinyl alcohol used in the present invention is a polyvinyl alcohol structure composed of repeating polyvinyl alcohol monomer structural units and a repeating structure of vinyl acetate monomer structure represented by the general formula (III). It has a vinyl acetate structure and has the following general formula (VIII)

[0029]

Embedded image (In the formula, b ₀ represents a mole fraction of a polyvinyl alcohol structure composed of repeating vinyl alcohol monomer structural units in polyvinyl alcohol, 0.7
It is a value in the range of to 1.0. In addition, c in the formula represents the mole fraction in the polyvinyl alcohol of the structure composed of the repeating unit represented by the general formula (III), and 0 to
The value is in the range of 0.3).

The esterifying agent used in the carbonic acid esterification reaction of the polyvinyl alcohol in the present invention includes the above-mentioned general formula (VI) (in the formula, R ₁ and R
₂ represents a hydrogen atom, or a lower alkyl group or a lower alkoxy group having 1 to 4 carbon atoms, R ₁
And R ₂ may be the same or different). Specifically, R ₁ and R ₂ may be the same or different and each is a hydrogen atom, and a methyl group, ethyl group, n-propyl group bonded to the ortho, meta or para position with respect to the benzene nucleus. Group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, methoxy group, ethoxy group,
A diaryl carbonate represented by the above general formula (VI), which is selected from the group consisting of a propoxy group and a butoxy group, and examples thereof include diphenyl carbonate, di (o-methylphenyl) carbonate, and di (m-methylphenyl carbonate). ), Di (p-methylphenyl) carbonate, di (o-ethylphenyl) carbonate, di (m-ethylphenyl) carbonate, di (p-ethylphenyl) carbonate, di (on-propylphenyl) carbonate, carbonic acid Di (on-butylphenyl), di (o-carbonate)
-Methoxyphenyl), di (o-ethoxyphenyl) carbonate, di (o-propoxyphenyl) carbonate, di (o) carbonate
-Butoxyphenyl), carbonic acid o-methylphenylphenyl, carbonic acid m-methylphenylphenyl, carbonic acid o-methoxyphenylphenyl, carbonic acid o-methylphenyl.
Examples thereof include o-ethylphenyl, o-methylphenyl carbonate and o-methoxyphenyl carbonate. In some cases, it is possible to use them as a mixture thereof. In the present invention, in consideration of economical efficiency and availability, among the above, a diaryl carbonate in which R ₁ and R ₂ in the general formula (VI) are the same is preferable, and specifically, Is preferably diphenyl carbonate or di (o-methoxyphenyl) carbonate, particularly preferably diphenyl carbonate.

It is necessary to use the diaryl carbonate in an amount corresponding to the desired value of the carbonic acid esterification degree represented by the above formula (III). That is, as described above, the carbonic acid esterification degree can be 1 mol% or more and the theoretical maximum esterification degree based on Flory's theory, which is 81.6 mol% or less. 1 to the purpose
70 mol% is preferable, and from the residual polyvinyl alcohol properties to those in which the polyvinyl alcohol properties are greatly modified, the above-mentioned carbonic acid is used depending on various uses of the obtained carbonic acid esterified PVA derivative. The degree of esterification can be chosen and a corresponding amount of the diaryl carbonate may be used, depending on the degree of carbonic acid esterification. Specifically, the diaryl carbonate is 0.1 to 20 times the molar amount of polyvinyl alcohol, preferably 0.1.
It is preferable to use 1 to 10 times the molar amount. When the amount used is less than 0.1 times the molar amount, the carbonic acid esterification reaction of polyvinyl alcohol hardly progresses, so that the carbonic acid esterification degree cannot be at least 1 mol% or more, and the property of polyvinyl alcohol is The improved carbonic acid esterified PVA derivative of interest cannot be efficiently obtained, which is not preferable. Further, if the amount used is more than 20 times the molar amount, the degree of carbonic acid esterification can hardly be expected to be improved, which is not preferable in terms of profitability. Further, in the carbonic acid esterification reaction, gel formation becomes remarkable, and a homogeneous reaction is caused. Since it becomes difficult to carry out the reaction, the stability of the reaction system may decrease, which is not preferable. The formation of a remarkable gel during the carbonic acid esterification reaction is accompanied by an increase in the carbonic acid esterification degree in the obtained carbonic acid esterified PVA derivative having a crosslinked carbonic acid ester structure composed of the repeating unit represented by the general formula (V). It is considered that the reason is that the formation of intermolecular cross-links due to the formation becomes remarkable, and the solubility of polyvinyl alcohol in the reaction solvent, which will be described later, decreases due to the increase in the amount of the diaryl carbonate used. Further, when the amount of the diaryl carbonate used is in the range of 10 to 20 times by mole, there is a tendency that improvement in the carbonic acid esterification degree cannot be expected, and at the time of the carbonic acid esterification reaction, the intermolecular chain due to the crosslinked carbonic acid ester structure is increased. The stability of the reaction system may decrease due to gelation due to the formation of cross-links and the decrease in the solubility of polyvinyl alcohol in the reaction solvent described later. As the amount of the diaryl carbonate used with respect to the amount of polyvinyl alcohol increases, gelation of the reaction system during the carbonic acid esterification reaction is more likely to occur due to the reasons described above, but to what extent the diaryl carbonate is used. Whether gelation can occur in the amount depends on the type and amount of the solvent and the catalyst used, the reaction temperature, the reaction time, and the like, and it cannot be unequivocally stated. However, the carbonic acid esterification reaction should be controlled so as to minimize gelation of the undesired reaction system. For example, in the carbonic acid esterification reaction of polyvinyl alcohol in a dimethylsulfoxide solvent, the amount of the diaryl carbonate used is preferably not more than 5 times the molar amount of polyvinyl alcohol so that gelation of the reaction system does not occur. preferable.

As the reaction solvent of the present invention, those having the action of dissolving or swelling the polyvinyl alcohol and having no reactivity with the diaryl carbonate, that is, an aprotic polar solvent can be used. Examples of the aprotic polar solvent include amide compounds such as formamide, N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAC) and hexamethylphosphoric amide (HMPA), and dimethyl sulfoxide (DMSO). , N-methyl-2-pyrrolidone (NMP) and the like can be preferably mentioned, and among these, use of DMSO, DMAC, NMP and the like is preferable, and use of DMSO is particularly preferable. Further, in the present invention, a mixture of the aprotic polar solvent with an organic solvent which forms a homogeneous phase and has no reactivity with the diaryl carbonate can also be used. Examples of the organic solvent include aliphatic hydrocarbons such as n-hexane and n-octane, aromatic hydrocarbons such as benzene, toluene and xylene, ketones such as acetone, methyl ethyl ketone and methyl propyl ketone, dichloromethane and dichloroethane. Specific examples thereof include halogenated hydrocarbons, ethers, dioxane and tetrahydrofuran.

The amount of the reaction solvent used may be at least an amount sufficient to dissolve or swell the polyvinyl alcohol. The type of the reaction solvent used, as well as the charged amount of the polyvinyl alcohol and the diaryl carbonate, may be used. Kind and amount of use, kind and amount of catalyst, reaction temperature, reaction time and other carbonic acid esterification reaction conditions, further, in the carbonic acid esterification reaction, the polyvinyl alcohol is dissolved in the reaction solvent, or the reaction solvent Since it depends on whether or not it swells at, it is difficult to specify it unconditionally. Therefore, for example, DMSO is used as the reaction solvent.
When using, the amount of the reaction solvent (DMSO) used is preferably 1 to 60 times (volume ratio) of the polyvinyl alcohol. When the amount used is less than 1 time, the polyvinyl alcohol is not sufficiently dissolved in the DMSO solvent,
Since the reaction proceeds in a heterogeneous system, uniform carbonation becomes difficult, and the resulting carbonized PV
It is not preferable because the quality of the A derivative varies.
On the other hand, even if a DMSO solvent in excess of 60 times is used, the effect of the reaction solvent of dissolving the polyvinyl alcohol and advancing the carbonic acid esterification reaction by the diaryl carbonate in a homogeneous system has already been achieved. ,
Further effects cannot be expected, and more than necessary energy is consumed for recovering the DMSO solvent from the reaction system by the method described later, which is not profitable.

In the present invention, as described above, various kinds of physical and chemical substances are used, from water-soluble substances to water-insoluble substances, depending on the purpose of use (use). Since the target is a carbonate esterified PVA derivative, when selecting the above reaction solvent,
Depending on the use of the obtained carbonic acid esterified PVA derivative,
In other words, an appropriate reaction solvent should be selected depending on where the target value of the degree of carbonic acid esterification is set to carry out the carbonic acid esterification reaction.

In the present invention, in the carbonic acid esterification reaction of the polyvinyl alcohol with the diaryl carbonate, an alkyl ammonium salt, a pyridinium salt, a diazabicycloalkene, a tertiary amine, an alkyl ammonium group or a tertiary amino group is used. An esterification reaction catalyst which is a base catalyst selected from the group consisting of an ion exchange resin and an alkaline catalyst contained therein can be used. The catalyst has a function of promoting the carbonic acid esterification reaction of polyvinyl alcohol as shown by the following formula (IX).

[0036]

Embedded image

The alkylammonium salt as the esterification reaction catalyst of the present invention is a compound represented by the following general formula (X).

[0038]

Embedded image (Wherein, R _{3 to} R ₆ represent a hydrogen atom, a hydroxyalkyl group, an alkyl group, an aryl group, or an aralkyl group which may be the same or different from each other, and when these are an alkyl group or an aralkyl group, Is a linear, branched or cyclic hydrocarbon group having 1 to 30 carbon atoms, and X is a halogen atom, a hydroxyl group, an alkoxide, a carbonate group, a bicarbonate group, a dihydrogen phosphate group and a bisulfate. Represents a monovalent anion selected from the group consisting of groups)

Specific examples of the alkyl ammonium salt and the pyridinium salt are tetra n-butyl ammonium chloride (TBAC), tetra n-butyl ammonium bromide (TBAB) and tetra n-butyl ammonium iodide (TBAI). , Tetra-n-butylammonium fluoride (TBAF)
Such as tetrabutylammonium halide (TBA
X), tri-n-butylamine hydrochloride, tetra-n-butylammonium dihydrogen phosphate, trimethylammonium iodide, trimethylamine hydrochloride, trimethylbenzylammonium chloride, tetraoctylammonium bromide, tetra-n-butylammonium hydroxide, tetrahydrogensulfate Examples thereof include n-butylammonium, pyridinium methyl iodide, pyridine hydrochloride, trimethyl 2-hydroxyethylammonium chloride and a mixture of two or more thereof. Further, as the diazabicycloalkene, 1,8-diazabicyclo [5,4,0] 7-undecene (DBU) and the like can be preferably mentioned. Examples of the tertiary amine include all amines having one electron pair and an aliphatic hydrocarbon substituent and / or an aromatic hydrocarbon substituent, and in particular, the following general formula (XI The tertiary amines represented by) are preferred.

[0040]

Embedded image (Wherein, R _{7 to} R ₉ represent a linear, branched or cyclic alkyl group having 1 to 30 carbon atoms, which may be the same or different, a hydroxyalkyl group, an aryl group, or an aralkyl group. .)

Specifically, triethylamine and tri-n-
Propylamine, tri-n-butylamine, methyldiethylamine, N, N-dimethylcyclohexylamine, pyridine, N, N-dimethylethanolamine, N, N-
Mention may be made of diethylpropanolamine and mixtures of two or more of these. Further, the above-mentioned ion exchange resin that can be used as the esterification reaction catalyst in the present invention is a strongly basic or weakly basic anion exchange resin catalyst containing an alkylammonium group or a tertiary amino group as an active group. . A typical example of a strongly basic anion exchange resin catalyst is produced by reacting a chloromethylated styrene / divinylbenzene copolymer with a tertiary amine selected from trimethylamine or N, N-dimethylethanolamine. A quaternary ammonium salt derivative of a styrene / divinylbenzene copolymer that can be used, specifically, Amberlite IRA-400 (Cl) or Amberlite IRA-400 (OH) manufactured by Rohm and Haas Co., Suitable examples include anion exchange resins such as Dowex 1X2-100 manufactured by Dow Chemical Company. On the other hand, examples of weakly basic anion exchange resins include amine derivatives of chloromethylated polystyrene, polycondensation products of epichlorohydrin with secondary or tertiary amines, amination polycondensation products of phenol with formaldehyde, and the like. As a representative example,
Specifically, anion exchange resins such as Amberlite IRA-93 and Duolite A-75 manufactured by Rohm and Haas are preferable. Furthermore, examples of the alkaline catalyst used in the present invention include potassium hydroxide, sodium hydroxide, sodium hydride, metallic sodium, potassium amide, sodium amide, potassium alcoholate such as potassium methylate and potassium ethylate (particularly potassium hydroxide). Specific examples thereof include sodium alcoholate (especially sodium methylate) such as methylate), sodium methylate and sodium ethylate.

In the present invention, it is preferable to use TBAX, DBU, triethylamine, tri-n-propylamine, tri-n-butylamine and the like such as TBAC, TBAB and TBAI among the esterification reaction catalysts described above. When the quaternary ammonium salt TBAX is used, the carbonic acid esterification increases as the electronegativity of the halogen increases in the order of TBAI <TBAB <TBAC, that is, the more easily the quaternary ammonium salt dissociates. Since the yield of the PVA derivative and the degree of carbonic acid esterification shown by the above formula (III) increase, it can be said from the above that it is preferable to use TBAC>TBAB> TBAI in the order of TBAX. TBAF, which is one of TBAX of quaternary ammonium salt, is
Although it has the highest electronegativity among the primary ammonium salts, like the case of DBU, since it is a strong base and the catalyst is too strong, the carbonic acid esterification PVA derivative obtained by accelerating the carbonic acid esterification reaction is obtained. It is considered that decomposition occurs, the yield of the carbonic acid esterified PVA derivative decreases as compared with other quaternary ammonium salts, and the monocarbonic acid ester structure composed of the repeating unit represented by the general formula (IV) is considerably reduced. It becomes a carbonic acid esterified PVA derivative that has many. And this carbonate esterified PVA
Decomposition of the derivative is also observed when TBAC is used as the esterification reaction catalyst, and in this case, as compared with the case where TBAB or TBAI is used as the esterification reaction catalyst, in the obtained carbonic acid esterified PVA derivative, It is considered that the composition ratio of the monocarbonate structure composed of the repeating unit represented by the general formula (IV) increases.
From the above, among the above TBAX, TBAB
Is most preferably used.

As described above, various base catalysts can be used in the carbonic acid esterification reaction of the polyvinyl alcohol with the diaryl carbonate, but in the present invention,
These esterification reaction catalysts are not essential. That is, the carbonic acid esterification reaction proceeds even in the absence of the esterification reaction catalyst. In this case, the reaction is, for example, D
When carried out in the presence of an aprotic polar solvent such as MSO, the following general formula (XII)

[0044]

Embedded image

[0045] (wherein Shikichu, R ₁ and R ₂ are each the general formula (VI) as defined represent R ₁ and R ₂ in) as shown in the reaction is believed to proceed, the Carbonated PVA rich in monocarbonate structure consisting of repeating units represented by the general formula (IV)
A derivative is obtained. Therefore, the amount of the above-mentioned esterification reaction catalyst required for the carbonic acid esterification reaction is the charged amount of the polyvinyl alcohol, the type and amount of the diaryl carbonate, the type and amount of the reaction solvent,
The reaction temperature, the reaction pressure, the reaction time, and the carbonic acid esterification reaction conditions such as the target value of the carbonic acid esterification degree vary depending on the conditions and cannot be unconditionally limited. When a catalyst is used, 50% by weight or less, preferably 30% by weight or less, based on the polyvinyl alcohol, and when other catalysts are used, 25 mol% or less, and preferably 25 mol% or less based on the polyvinyl alcohol. It is preferably 10 mol% or less. The amount of the esterification reaction catalyst used is 50% by weight or 25% by mole with respect to the polyvinyl alcohol.
Even if the amount is increased, the preferable effect is hardly improved by using a large amount of the catalyst, which is not preferable from the economical aspect.

The carbonic acid esterification reaction of the present invention needs to proceed in a homogeneous system in a solution. That is, it is necessary to carry out the carbonic acid esterification reaction in a state in which the polyvinyl alcohol is dissolved in the reaction solvent, or in a state in which the polyvinyl alcohol is swollen in the reaction solvent, and for that purpose, the carbonic acid esterification is performed. While the reaction is in progress,
The reaction solvent should be maintained in a liquid state. Therefore, the reaction temperature is at least the melting point of the reaction solvent,
In addition, the temperature is preferably in the range of the boiling point of the reaction solvent or less. However, in this case, the reaction temperature is 20
If the temperature exceeds 0 ° C., an undesired thermal decomposition reaction of the raw material polyvinyl alcohol will occur simultaneously. Therefore, the reaction temperature in the carbonic acid esterification reaction of the present invention is not less than the melting point of the reaction solvent and the boiling point of the reaction solvent or 200 ° C
It is preferable that the temperature is lower than the lower one of the two.

In the carbonic acid esterification reaction of the present invention, the reaction pressure is not particularly limited, and it can be carried out under any of reduced pressure, normal pressure and increased pressure. However, in the case of pressurization, pressure resistance performance is required of the manufacturing equipment, and in the case of decompression, pressure reduction equipment is required. The higher the temperature of the carbonic acid esterification reaction, the faster the reaction rate. Therefore, when it is necessary to increase the yield of the carbonic acid esterified PVA derivative to be obtained and the degree of carbonic acid esterification, the reaction temperature should be within the above range. It is better to raise the temperature.
However, if the temperature at the time of the reaction of the carbonic acid esterification reaction is too high, the reaction becomes non-uniform and the quality of the resulting carbonic acid esterified PVA derivative such as meltability, transparency and mechanical properties is adversely affected, The diaryl carbonate or reaction solvent used may become thermally unstable. Therefore, in such a case, it is preferable to reduce the pressure of the reaction system to maintain the reaction temperature at a low level. The reaction time also varies depending on the carbonic acid esterification conditions such as the charged amount of the polyvinyl alcohol, the type and amount of the diaryl carbonate, the type and amount of the reaction solvent, the reaction temperature, and the target value of the carbonic acid esterification degree, 5 minutes to 50
It is suitable for about time, preferably about 10 minutes to 30 hours. If the time is less than about 5 minutes, the carbonic acid esterification reaction of the polyvinyl alcohol does not proceed sufficiently, resulting in carbonic acid esterified PV.
A derivative cannot be obtained with the target yield and degree of carbonic acid esterification, and when it is longer than about 50 hours,
Further improvement in the degree of carbonic acid esterification cannot be expected, and the formation of intermolecular chain crosslink bonds due to the formation of the crosslinked carbonic acid ester structure composed of the repeating unit represented by the general formula (V) becomes remarkable, which is not preferable for the present invention. Undesirable reaction system gelation is promoted and the resulting carbonate esterified PV
In any case, the derivative A may be subjected to a long-term heat history, resulting in deterioration of quality due to heat deterioration.

The carbonic acid esterification reaction of the present invention is preferably carried out while stirring by an appropriate method such as mechanical stirring with a stirrer. The carbonic acid esterification reaction of the present invention is preferably carried out in an inert gas atmosphere in order to prevent undesired hydrolysis and oxidation of the resulting carbonic acid esterified PVA derivative. As an inert gas,
In addition to nitrogen gas, rare gases such as argon gas and helium gas can be preferably used.

In the present invention, the method for producing the carbonic acid esterified PVA derivative by the carbonic acid esterification of the polyvinyl alcohol is not particularly limited and may be carried out according to a conventional method, either batch type or continuous type. Can also be implemented. For example, after dissolving or swelling a predetermined amount of the polyvinyl alcohol in a predetermined amount of the reaction solvent, it is supplied to a reaction device with a suitable stirrer, further, a predetermined amount of the diaryl carbonate and esterification reaction catalyst, respectively, The reaction may be carried out by heating at a predetermined temperature with stirring under a normal pressure, or a predetermined reduced pressure or a predetermined pressure, and performing a reaction for a predetermined time. In this case, the diaryl carbonate may be added in divided amounts as appropriate without being added in a predetermined amount at a time. Also, the esterification reaction catalyst may be added to the reaction system in a required amount at one time, or may be divided and added in an appropriate number of times. Furthermore, in the present invention, based on the crosslinked carbonic acid ester structure during the carbonic acid esterification reaction, in order to prevent the formation of intermolecular cross-linking bonds, in the carbonic acid esterification reaction, the selection of the degree of polymerization of the raw material polyvinyl alcohol,
It is also necessary to consider the selection of carbonic acid esterification reaction conditions that are as gentle as possible within the range of the reaction temperature and reaction time described above.

In the method of the present invention, subsequently, the reaction solution obtained as described above is added to the precipitation solvent, and the mixture is allowed to stand for an appropriate period (for example, one day and one night) to obtain the above-mentioned general formula (VII). Carbonated esterified P having the chemical structure shown in
A precipitate of the VA derivative is obtained. The precipitation solvent may be a poor solvent for the carbonic acid esterified PVA derivative, and is an alcohol having 1 to 4 carbon atoms which is liquid at room temperature, for example, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol. , N-butyl alcohol, isobutyl alcohol, sec-butyl alcohol and the like. Of these, methyl alcohol and ethyl alcohol are preferable, and ethyl alcohol is particularly preferable. The amount of the precipitation solvent used is preferably 1 to 20 times (volume ratio) the amount of the reaction solution. If the amount used is less than 1 time,
The carbonate esterified PVA derivative is not sufficiently precipitated from the reaction solution, which is not preferable. In addition, if the amount used is more than 20 times, further effects of the precipitation solvent cannot be expected, and more energy is consumed for recovery of the precipitation solvent, which is economically unfavorable. There is. When a solid catalyst such as the above-mentioned ion exchange resin catalyst is present in the above-mentioned carbonic acid esterification reaction, prior to addition of the reaction solution to the above precipitation solvent, filtration, centrifugation, other known It is necessary to separate the solid content from the reaction solution according to the method.

Therefore, the reaction mixture containing the carbonate esterified PVA derivative precipitate is separated into solids by a known method such as filtration or centrifugation. Then, the solid content is washed with the same solvent as that used as the precipitation solvent, for example, ethyl alcohol, and then the same solvent as that used as the precipitation solvent, for example, ethyl alcohol as an extraction solvent, Soxhlet extraction, etc. Carbonate esterified PVA which is a extraction residue after extraction treatment by a known method
The derivative is purified by removing impurities such as residual reaction solvent. Then, the obtained raffinate is dried at a temperature of 100 ° C. or lower by a known method such as hot air drying, vacuum drying, and freeze drying, so that it has the above-mentioned various characteristics and the general formula (VII Thus, the carbonic acid esterified PVA derivative of the present invention having the chemical structure shown in (1) can be obtained.

By the way, in the present invention, when the composition ratio of the monocarbonic acid ester structure consisting of the repeating unit represented by the general formula (IV) in the carbonic acid esterified PVA derivative obtained by the carbonic acid esterification reaction increases, When the carbonic acid esterified PVA derivative is added to a precipitation solvent, for example, ethyl alcohol, the phenoxy group or the substituted phenoxy group in the monocarbonic acid ester structure has an affinity for ethyl alcohol,
Precipitation of carbonate esterified PVA derivative is unlikely to occur because the derivative becomes soluble. Therefore, in the present invention,
When the solid mixture (polymer product) is separated and collected by filtration, centrifugation or the like of the reaction mixture containing the carbonate esterified PVA derivative precipitate, the obtained filtrate is collected,
By using an evaporator or a rotary evaporator, the ethyl alcohol and the reaction solvent in the filtrate are removed by evaporation and concentration to remove the carbonate esterified PVA derivative dissolved in the filtrate, and then the precipitate It is desirable to recover the carbonic acid esterified PVA derivative that does not precipitate by adding the reaction solution to the precipitation solvent by performing separation / collection, washing with a small amount of solvent and drying in the same manner as described above.

Then, when recovering the polymer product from the above-mentioned filtrate, the solvent evaporated from the filtrate and the filtrate obtained when separating and recovering the precipitate of the polymer product obtained by concentrating the filtrate are unreacted. Polyvinyl alcohol, diaryl carbonate, reaction solvent, esterification reaction catalyst,
It contains a by-product phenolic compound, a precipitation solvent, and the like. These are, if necessary, recovered, and then subjected to distillation, column chromatography such as liquid chromatography, recrystallization, selective solvent extraction, and JP-A-5-125021. A known separation operation method such as a pervaporation method or a vapor permeation method using a selective permeation membrane disclosed in JP-A-6-157407 or the like is used alone or in appropriate combination. The above substances are isolated and reused.

[0054]

EXAMPLES Next, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples and comparative examples. In the following examples and comparative examples, the characteristics of the carbonic acid esterified PVA derivative (however, in the comparative examples, the obtained solid matter) and the molded articles thereof were determined by the following methods.

(1) Carbonation degree of carbonic acid esterified PVA derivative 100 mg of a carbonic acid esterified PVA derivative sample
After drying under reduced pressure at 0 ° C. for 2 hours or more to sufficiently remove water, the material was precisely weighed by the displacement weighing method. This has a capacity of 200 ml
0.5m Sodium hydroxide (NaOH) solution [commercial item (for volumetric analysis)] 30m
1 was added and hydrolyzed at room temperature overnight. At this time, most of the carbonic acid esterified PVA derivative sample was dissolved, and the cyclic carbonic acid ester structure composed of the repeating unit represented by the general formula (I) and the repeating unit represented by the general formula (IV) in the sample were dissolved. And the ester moiety of the crosslinked carbonic acid ester structure composed of the repeating unit represented by the general formula (V) were hydrolyzed. In addition, the same operation as described above was carried out with a system containing no carbonate esterified PVA derivative sample as a blank. Then, these are heated on a hot plate at 70 ° C. for 4 hours and allowed to cool at room temperature, and then ion-exchanged water 5
0 ml was added, and the mixture was titrated with a 0.5N hydrochloric acid (HCl) solution [commercial item (for volumetric analysis)] while stirring. In addition,
For this titration, an automatic titrator (Mitsubishi Chemical Co., Ltd., GT-
Type 05) was used. Then, by acid-base titration with hydrochloric acid, there are three types of inflection points: a point of neutralization with excess alkali (point A), a point of neutralization with sodium carbonate (point B), and a point of neutralization with sodium hydrogen carbonate (point C). From the titration result, the consumption amount of the alkali consumed for the hydrolysis of the carbonic acid esterified PVA derivative sample was calculated, and the carbonic acid esterification degree of the carbonic acid esterified PVA derivative was calculated by the following mathematical formula (IV).

[0056]

(Equation 4)

(2) Infrared absorption spectrum (IR) of carbonate esterified PVA derivative It was measured by the following method using an FT-8000 type Fourier infrared spectrophotometer manufactured by JASCO Corporation. (KBr tablet method) Carbonate esterified PVA derivative sample 1 m
g was mixed with 150 mg of KBr (manufactured by Merck), and 6
After drying under reduced pressure at 0 ° C. for 2 hours or more to remove water, pressure tablets were formed and measured. (Film method) A carbonate esterified PVA derivative sample, which was dried under reduced pressure at 60 ° C for 2 hours or more to remove water, was dissolved in formic acid (commercial special grade product, purity: about 99% by weight) to a concentration of about 5% by weight. Then, it was gently dried on a plastic petri dish to prepare a film, and the film was measured. (Liquid film method) NaCl was used as a window plate of an alkali salt.
A small amount of a liquid sample of carbonated PVA derivative was added to NaC.
It was cast on a 1-plate and measured.

(3) Specific gravity of carbonic acid esterified PVA derivative It was measured by a substitution method using n-hexane as a medium, using an MC-1 electronic balance manufactured by Sartorius KK

(4) Glass transition temperature and melting point of carbonic acid esterified PVA derivative Differential scanning calorimeter (DSC-50 manufactured by Shimadzu Corporation)
Was measured under the conditions of a temperature rising rate of 20 ° C./min.

(5) Tensile Properties of Molded Articles Measured using a model 2005 tensile tester manufactured by Intesco Corporation. After molding a dried sample of a carbonic acid esterified PVA derivative (a carbonic acid esterified PVA derivative dried under reduced pressure at 60 ° C. for 2 hours or more to remove water), it was molded at 23 ° C. and a relative humidity of 50% (hereinafter abbreviated as “50% RH”). ) For 48 hours. Then, the yield point strength of the obtained test piece,
Measure strength at break and elongation at break according to ASTM D
According to 638, it was performed at 23 ° C. and 50% RH.

Example 1 (Preparation of Polyvinyl Alcohol / Dimethyl Sulfoxide Solution) Polyvinyl alcohol powder dried under reduced pressure at 60 ° C. for 3 hours or more (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., brand: NH-
18, average polymerization degree: 1800, saponification degree: 98.3 mol%) 1.0 g (polyvinyl alcohol structural unit component:
(0.0223 mol) was precisely weighed and placed in a 100 ml Erlenmeyer flask. To this, add 30 ml of dimethyl sulfoxide (commercial grade) and keep at 80 ° C for 5 hours (or until the polyvinyl alcohol powder is completely dissolved).
After heating and dissolving, the polyvinyl alcohol powder was completely dissolved in the dimethyl sulfoxide by standing still for one day or more to prepare a polyvinyl alcohol / dimethyl sulfoxide solution.

(Carbonate Esterification Reaction of Polyvinyl Alcohol) Polyvinyl alcohol / dimethyl sulfoxide solution prepared as described above (hereinafter simply referred to as “solution”)
Tends to cause a difference in concentration between the lower layer and the upper layer of the solution over time, so in order to make the solution completely uniform, the solution is heated at 80 ° C. for 1 hour before the reaction. It was stirred. To this solution, tetra-n-butylammonium bromide as a catalyst (commercially available special grade product, hereinafter referred to as "TB
Abbreviation "AB") 63 mg (1.96 × 10 ^-4 mol) and diphenyl carbonate (manufactured by Tokyo Chemical Industry Co., Ltd., purity: 99.0).
(Wt% or more) 6.10 g (0.0285 mol) was added, and then the above dimethyl sulfoxide was further added so that the total reaction system was 60 ml, and the mixture was stirred with a magnetic stirrer up to 120 ° C in an oil bath. The temperature was raised and the temperature was maintained for 6 hours to carry out a carbonic acid esterification reaction of polyvinyl alcohol.

The carbonic acid esterification reaction of polyvinyl alcohol proceeded in a homogeneous system, and no gelled material was observed during the reaction. After the lapse of the predetermined time, the reaction solution was poured into 500 ml of ethyl alcohol (commercial product) having a purity of 99% by volume to precipitate a polymer product, which was left standing overnight and then separated and collected by centrifugation. The recovered polymer product was further washed 3 times with 500 ml of the ethyl alcohol each time. Next, this polymer product was used with 500 ml of the ethyl alcohol as an extraction solvent,
The product was extracted with a Soxhlet extractor for 3 days for purification.
On the other hand, the filtrate obtained by the centrifugation is, after recovery, concentrated and removed ethyl alcohol of the precipitation solvent and dimethyl sulfoxide of the reaction solvent by a rotary evaporator, to obtain a polymer product which does not precipitate by charging into the ethyl alcohol. The obtained product was washed with a small amount of the above ethyl alcohol. Therefore, the polymer product separated and recovered by the centrifugation and the polymer product recovered by the concentration removal of the solvent by the rotary evaporator are combined, and the ethyl alcohol attached to these polymer products is replaced with dioxane. Lyophilization was performed to obtain a powdered polymer product, that is, a carbonic acid esterified PVA derivative. The carbonate esterified P
The yield of the VA derivative is 1.635 g, and is 0.5
The carbonic acid esterification degree (E) determined by the NNaOH solution hydrolysis method was 50.25 mol%.

Then, the carbonic acid esterified PV obtained above
In order to determine the chemical structure of the A derivative, infrared absorption spectrum (IR spectrum) measurement was performed in comparison with polyvinyl alcohol as a raw material. Carbonated esterified PV obtained
The IR spectrum of the A derivative is shown in FIG. 1 in comparison with that of the raw material polyvinyl alcohol, and the spectrum assignment is shown in Table 1.

[0065]

[Table 1]

This result shows that 1755 cm ^-1 and 1
C = O and C due to strong carbonic acid ester at 219 cm ^-1
Absorption due to stretching vibration of -O can be confirmed, and 770c
At m ⁻¹ and 870 cm ⁻¹ , absorption by cyclic carbonic acid ester could be confirmed. From this, it was possible to confirm the presence of a cyclic carbonic acid ester structure in the obtained carbonic acid esterified PVA derivative. Furthermore, since there is absorption by the stretching vibration of C-H by phenoxy groups 2858Cm ^-1, also, since the presence of weak absorption symmetry ring stretching vibration due to crosslinking carbonate to 889cm ^-1, the resulting carbonate It was also confirmed that a monocarbonate structure and a crosslinked carbonate structure were present in the esterified PVA derivative. Therefore, the obtained carbonic acid esterified PVA derivative has a cyclic carbonic acid ester structure composed of the repeating unit represented by the general formula (I) and a monocarbonic acid ester structure composed of the repeating unit represented by the general formula (IV). It was found that the compound had a chemical structure in which a crosslinked carbonic acid ester structure consisting of the repeating unit represented by the general formula (V) was slightly present.

Physical properties such as specific gravity, glass transition temperature and melting point of the obtained carbonic acid esterified PVA derivative were measured, and the results were as shown in Table 2. further,
The obtained carbonic acid esterified PVA derivative was dissolved in formic acid (commercial special grade product, purity: about 99% by weight) and gently dried on a plastic petri dish to form a film. A test piece for measuring physical properties was produced from this film, and the physical property, that is, the tensile property was measured using the test piece. Table 2 shows the results.

Example 2 The same operation as in Example 1 except that the amount of diphenyl carbonate used was changed to 6.10 g (0.0285 mol) to 1.20 g (5.61 × 10 ⁻³ mol). I went. No gel was observed in the reaction solution during the reaction, and the yield of the carbonic acid esterified PVA derivative in the form of white powder obtained by the same purification treatment as in Example 1 and the carbonic acid determined by the 0.5N NaOH solution hydrolysis method were used. The degree of esterification (E) was 1.167 g and 14.3 mol%, respectively. From the measurement result of the IR spectrum of the obtained carbonic acid esterified PVA derivative, the absorption based on the presence of the cyclic carbonic acid ester structure and the monocarbonic acid ester structure was confirmed, but the absorption based on the crosslinked carbonic acid ester structure was not confirmed. Also,
The results of measuring the physical properties of the carbonic acid esterified PVA derivative and the test piece for measuring the physical properties of the film were as shown in Table 2.

Example 3 The volume of the whole reaction system was changed to 60 ml by adding dimethyl sulfoxide to 50 ml, and the amount of diphenyl carbonate used was changed to 6.10 g (0.0285 mol) to 25.7 g ( The same operation as in Example 1 was performed, except that the amount was 0.120 mol). Although gel was observed in the reaction solution during the reaction, the reaction was continued for a predetermined time. After completion of the reaction, the yield of the spongy carbonic esterified PVA derivative obtained by the same purification treatment as in Example 1 and the carbonic acid esterification degree (E) determined by the 0.5N NaOH solution hydrolysis method were 1 and 2, respectively. .723 g and 6
It was 2.5 mol%.

Examples 4 and 5 In Examples 4 and 5, the amount of TBAB used as a catalyst was changed to 63 mg (1.96 × 10 ⁻⁴ mol) in Example 1 to obtain 16 mg (5.0 ×). The same operation as in Example 1 was performed except that the amount was 10 ⁻⁵ mol) and 0.378 g (1.17 × 10 ⁻³ mol). In any of the examples, generation of a gel-like substance was not observed during the reaction. The yield of the powdered carbonic acid esterified PVA derivative obtained in each example and the carbonic acid esterification degree (E) obtained by the 0.5N NaOH solution hydrolysis method are shown in Example 4.
1.604 g and 49.35 mol%, respectively, and in Example 5, 1.573 g and 53.35%, respectively.
It was 20 mol%. In addition, in each of the examples, the absorption based on the presence of the cyclic carbonic acid ester structure, the monocarbonic acid ester structure, and the crosslinked carbonic acid ester structure was confirmed from the measurement result of the IR spectrum of the obtained carbonic acid esterified PVA derivative.

Example 6 Diphenyl carbonate (manufactured by Tokyo Chemical Industry Co., Ltd., purity: 99.
0% by weight or more) 6.10 g (0.0285 mol) was used in place of di (o-methoxyphenyl) carbonate (Tokyo Chemical Industry Co., Ltd., first-class product) 7.81 g (0.0285 mol). Other than the above, the same operation as in Example 1 was performed.
No gel was observed during the reaction, and the carbonic esterified PV powder obtained by the same purification treatment as in Example 1 was used.
The yield of the A derivative and the carbonation degree (E) determined by the 0.5N NaOH solution hydrolysis method were, respectively,
1.627 g and 51.10 mol%. Also,
From the measurement results of the IR spectrum of the obtained carbonic acid esterified PVA derivative, absorption based on the presence of a cyclic carbonic acid ester structure, a monocarbonic acid ester structure, and a crosslinked carbonic acid ester structure was confirmed.

Comparative Example 1 As a blank test, diphenyl carbonate (manufactured by Tokyo Chemical Industry Co., Ltd., purity: 99.0% by weight or more) and TBAB (commercial special grade) as a catalyst were not added. The same operation as in Example 1 was performed. The amount of the obtained solid matter and the carbonation degree (E) determined by the 0.5N NaOH solution hydrolysis method were 0.986 g and substantially 0 mol%, respectively. That is, it was found that the obtained solid substance was the unreacted raw material polyvinyl alcohol itself. Table 2 shows the results of measuring the physical properties of the obtained solid matter and the film using the test piece for measuring the physical properties.

[0073]

[Table 2]

Comparative Example 2 Polyvinyl alcohol powder (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., brand name: NH-) which had been dried under reduced pressure at 60 ° C. for 3 hours or more in a glass autoclave having an internal volume of 200 ml.
18, average polymerization degree: 1800, saponification degree: 98.3 mol%) 1.0 g (polyvinyl alcohol structural unit component:
0.983 g, 0.0223 mol) and 30 ml of dimethylsulfoxide (commercial special grade product) were charged, and after purging with nitrogen gas, the mixture was heated at 80 ° C. for 5 hours while stirring,
Polyvinyl alcohol powder was dissolved in dimethyl sulfoxide. Next, when the temperature was raised to 220 ° C. with stirring, the solution began to turn yellow in the temperature rising process, and when it reached 220 ° C., it turned brown and stopped flowing, and after about 1 hour, it turned blackish brown. Since it became a gel and stirring became difficult, heating and stirring were stopped.

Comparative Example 3 Using the same glass autoclave as in Comparative Example 2,
The same treatment as in Comparative Example 2 was performed to prepare a dimethylsulfoxide solution of polyvinyl alcohol. Then, 63 mg of TBAB (commercial special grade) as a catalyst was added to this solution.
(1.96 × 10 ⁻⁴ mol) and diphenyl carbonate (manufactured by Tokyo Chemical Industry Co., Ltd., purity: 99.0% by weight or more) 6.10
After adding g (0.0285 mol), the total reaction system was 6
Dimethylsulfoxide (commercial special grade product) was further added so that the volume became 0 ml, and the mixture was purged with nitrogen gas. Then, 2
The temperature was raised to 20 ° C. and a carbonic acid esterification reaction of polyvinyl alcohol was tried. The above solution starts to turn yellow from the process of raising the temperature to 220 ° C., and upon completion of raising the temperature to 220 ° C., it turns brown and does not flow at the same time. The reaction was stopped.

From the results of Comparative Example 2 and this Comparative Example,
In the case where the reaction temperature was 220 ° C., it was presumed that diphenyl carbonate was not involved at all, that is, the decomposition of the raw material polyvinyl alcohol itself and the crosslinking reaction between polymer molecular chains were dominant. Therefore, the product of this comparative example was not worth further evaluating the chemical structure and physical properties.

[0077]

As described above, according to the present invention, a polymer having a 6-membered cyclic ester carbonate in the molecule,
Novel carbonated PVA with various physical and chemical properties ranging from water-soluble to water-insoluble
A derivative is obtained. Further, according to the method of the present invention, the above-mentioned carbonic acid esterified P which cannot be synthesized from the corresponding monomer is used.
The VA derivative can be efficiently produced, and the obtained carbonic acid esterified PVA derivative also has high quality. Therefore, the carbonic acid esterified PVA derivative of the present invention is a polyvinyl alcohol such as a fiber processing agent, a paper processing agent, an emulsion stabilizer, an adhesive, a pressure sensitive adhesive, a film, etc., depending on the physical and chemical properties of the obtained polymer ester. In addition to being used for its original purpose, water-insoluble substances alone or by mixing with other resins or plasticizers compatible with the polymer ester and modifying them, paints, adhesives, It can be effectively used for applications such as binders.

[Brief description of the drawings]

FIG. 1 is a view showing an IR spectrum of a carbonic acid esterified PVA derivative obtained in Example 1 and an IR spectrum of polyvinyl alcohol in comparison.

Claims (6)

[Claims] 1. A compound represented by the following general formula (I) (In the formula, a is a repeating unit represented by the formula and represents a mole fraction in a carbonate esterified polyvinyl alcohol derivative (hereinafter referred to as “carbonate esterified PVA derivative”)) And a cyclic carbonic acid ester structure consisting of the following general formula (II): (In the formula, b represents a mole fraction of the structure consisting of the repeating unit represented by the formula in the carbonate esterified PVA derivative), and the polyvinyl alcohol structure consisting of the repeating unit represented by the following general formula (III ) [Chemical 3] (Wherein c represents a mole fraction in the carbonic acid esterified PVA derivative of the structure consisting of the repeating unit represented by the formula, and is a value in the range of 0 to 0.3) And a polyvinyl acetate structure consisting of
Moreover, the following general formula (IV): (In the formula, R ₁ represents a hydrogen atom or an alkyl group or an alkoxy group having 1 to 4 carbon atoms, and d is a carbonic acid esterified PVA derivative having a structure consisting of the repeating unit represented by the formula. And a monocarbonate structure consisting of repeating units represented by the following general formula (V): (In the formula, e represents a mole fraction of the structure consisting of the repeating unit represented by the formula in the carbonic acid esterified PVA derivative), and contains a crosslinked carbonate structure consisting of the repeating unit. The values of a to e are the following formula (I): (In the formula, a, b, d and e have the same meanings as a, b, d and e in the general formulas (I), (II), (IV) and (V) respectively) and Formula (II) [Equation 2] (In the formula, a to e are respectively represented by the general formula (I).
To (V) have the same meaning as a to e in (V)) at the same time, a carbonic acid esterified PVA derivative. 2. Polyvinyl alcohol and the following general formula (V
I) [Chemical 6](However, in the formula, R₁Is R in the general formula (IV)₁
Has the same meaning as _TwoIs a hydrogen atom or 1 to 4
Alkyl or alkoxy groups having 4 carbon atoms
Represents Note that R₁And R_TwoAre the same or different
Reacting a diaryl carbonate represented by
The carbonic acid esterified PVA derivative according to claim 1,
Body manufacturing method. 3. A reaction solvent, in the presence or absence of an esterification reaction catalyst, above the melting point of the reaction solvent, and
The method for producing a carbonic acid esterified PVA derivative according to claim 2, wherein the polyvinyl alcohol and the diaryl carbonate are reacted in a temperature range not higher than the boiling point of the reaction solvent or 200 ° C., whichever is lower. 4. The carbonate esterified PV according to claim 3, wherein the reaction solvent is an aprotic polar solvent.
Method for producing A derivative. 5. The esterification reaction catalyst is an alkyl ammonium salt, a pyridinium salt, a diazabicycloalkene,
Carbonate esterification according to claim 3 or 4, which is a base catalyst selected from the group consisting of a tertiary amine, an ion exchange resin containing an alkylammonium group or a tertiary amino group, and an alkaline catalyst. PVA
Method for producing derivative. 6. The method for producing a carbonated PVA derivative according to claim 2, wherein the diaryl carbonate is diphenyl carbonate.