JPH08217832A - Molding - Google Patents

Abstract

(57) [Abstract] [Purpose] Excellent mechanical strength, and when used in combination with other hydrophobic resins, it does not reduce the mechanical strength of other hydrophobic resins and is excellent in moldability. To provide a molded product of polyvinyl alcohol resin. A novel polyvinyl alcohol-based resin comprising a copolymer containing 0.1 to 20 mol% of an ethylenically unsaturated dicarboxylic acid monoamide containing a specific N, N-dibranched alkylamide component as a copolymerization component Become.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded article using polyvinyl alcohol (hereinafter abbreviated as PVA), and more particularly to a molded article using a novel PVA resin and having excellent mechanical strength.

[0002]

2. Description of the Related Art Conventionally, it has been widely used for molded articles such as fibers, films, sheets, pipes, tubes, drip-proof films, temporary films and water-soluble fibers for chemical lace. Then, it has been attempted to introduce a sulfonic acid group into PVA for the purpose of improving antistatic property, antifogging property, water dispersibility in water-soluble use, lowering dew condensation property and improving moldability of the molded product. There is.

[0003]

However, in the case of introducing the above-mentioned sulfonic acid group, the (meth) allylsulfonic acid (sodium) and vinyl acetate are copolymerized and then saponified. Modification with sulfonic acids tends to reduce the mechanical strength of the obtained molded product.

[0004]

As a result of intensive studies to solve the above drawbacks, the present inventor has found that an ethylenic compound containing an N, N-dibranched alkylamide component represented by the following chemical formula 1 as a modifying component. Saturated dicarboxylic acid monoamide (A)
PVA containing 0.1 to 20 mol% of a copolymer component
Molded products of resin series have excellent mechanical strength, antistatic properties,
It was found that the mechanical strength of the resin does not decrease even if it is blended with other hydrophobic resin for the purpose of imparting hydrophilicity, and the present invention has been completed.

Embedded image Here, R ₀ is shown in Chemical formula 2.

Embedded image (However, n is 1 to 3, R _{1 to} R ₃ are each hydrogen or an alkyl group or an aryl group, and two or more are not hydrogen at the same time, and the total number of carbon atoms of R _{1 to} R ₃ is 4 or more.)

The present invention will be described in detail below. The modified PVA (hereinafter sometimes simply referred to as modified PVA) -based resin of the present invention contains the (A) unit as an essential component as described above, and the (A) unit is the N, N-dicarboxylic acid represented by the above chemical formula 1. An ethylenically unsaturated dicarboxylic acid monoamide unit containing a branched alkylamide component and having the above-mentioned functional groups of R _{1 to} R ₃ . Examples of the copolymerizable monomer containing the (A) unit include N, N-diisobutyl maleic acid monoamide, N, N-diisoamyl maleic acid monoamide, N,
N-di (2-ethylhexyl) maleic acid monoamide,
N, N-diisobutyl fumaric acid monoamide, N, N-diisoamyl fumaric acid monoamide, N, N-di (2-ethylhexyl) fumaric acid monoamide, N, N-diisobutylitaconic acid monoamide, N, N-diisoamylitaconic acid Monoamide, N, N-di (2-ethylhexyl) itaconic acid monoamide, N, N-diisobutyl citraconic acid monoamide, N, N-diisoamyl citraconic acid monoamide, N, N-di (2-ethylhexyl) citraconic acid monoamide, etc. Of these, N, N-diisobutyl maleic acid monoamide is preferably used. The carboxylic acid component in the (A) unit of the modified PVA-based resin of the present invention is a free carboxyl group or a salt thereof.

Usually, in order to produce the modified PVA resin of the present invention, the vinyl ester copolymer obtained by copolymerizing (A) and the vinyl ester (B) is saponified. Examples of (B) include vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, and the like, and vinyl acetate is preferable from the economical viewpoint.

The ratio of each unit of the modified PVA resin is
N, N shown in the above chemical formula 1 from the viewpoint of film forming property and economical efficiency
An ethylenically unsaturated dicarboxylic acid monoamide unit (A) containing a dibranched alkylamide component (A) in an amount of 0.1 to 20 mol%, preferably 0.1 to 10 mol%, a vinyl ester unit (B) and a vinyl alcohol unit ( C) is 8 in total
A range of 0 to 99.9 mol% is suitable. Furthermore, the saponification degree (vinyl alcohol unit (C) relative to the total amount of vinyl ester unit (B) and vinyl alcohol unit (C))
Is not particularly limited, but is preferably 60 mol% or more from the viewpoint of productivity of the modified PVA-based resin and the like.

The degree of polymerization of the modified PVA resin used in the present invention is not particularly limited, but it is preferably 300 to 3,000. If the degree of polymerization is less than 300, the mechanical strength will decrease, and conversely, if it exceeds 3,000, the moldability will increase. It tends to decrease.

Next, the method for producing the modified PVA resin of the present invention will be described. The modified PVA-based resin of the present invention saponifies the copolymer of the above-mentioned ethylenically unsaturated dicarboxylic acid monoamide monomer containing the N, N-dibranched alkylamide component represented by Chemical Formula 1 and vinyl ester. Obtained by

Such ethylenically unsaturated dicarboxylic acid monoamides (A) include maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid,
An ethylenically unsaturated dicarboxylic acid such as citraconic anhydride or an anhydride thereof, or an acid halide thereof is used with a secondary amine represented by Chemical formula 3 without catalyst or with a suitable acid catalyst (sulfuric acid,
It can be obtained by reacting in the presence of hydrochloric acid, a protonic acid such as P-toluenesulfonic acid). Such amines include diisobutylamine, diisoamylamine,
Di (2-ethylhexyl) amine may be mentioned.

Embedded image Here, R ₀ is shown in Chemical formula 2.

Embedded image (However, n is 1 to 3, R _{1 to} R ₃ are each hydrogen or an alkyl group or an aryl group, and two or more are not hydrogen at the same time, and the total number of carbon atoms of R _{1 to} R ₃ is 4 or more.)

In the polymerization, other unsaturated monomers copolymerizable with the monomers other than the above-mentioned two components, such as alkyl vinyl ether, methacrylamide, ethylene, propylene, as long as the gist of the present invention is not impaired. ,
Olefins such as α-hexene, α-octene, α-dodecene and α-octadodecene, nitriles such as acrylonitrile and methacrylonitrile, alkyl acrylates, methacrylic acid alkyl esters, crotonic acid alkyl esters, maleic acid dialkyl esters, itacone A small amount of acid dialkyl ester, citraconic acid dialkyl ester, fumaric acid dialkyl ester and the like may be copolymerized.

The copolymerization reaction is a known polymerization method in radical polymerization, for example, bulk polymerization, solution polymerization, emulsion polymerization,
Although it can be arbitrarily selected from suspension polymerization and the like, solution polymerization is preferable from the industrial viewpoint. Further, any method such as batch polymerization and continuous polymerization can be selected. There are no particular restrictions on the method of charging the monomers during the polymerization, and any method such as batch charging, divided charging, continuous charging may be employed. Branched alkyl acrylamide and ethylenically unsaturated carboxylic acid or salts thereof are used as PVA molecules. A divided charging method or a continuous charging method is advantageous in that it can be uniformly introduced into the inside.

As a catalyst for the copolymerization, known radical polymerization catalysts such as azobisisobutylnitrile, acetyl peroxide, benzoyl peroxide, and lauryl peroxide, and low-temperature active radicals such as azobisdimethylvaleronitrile and azobismethoxydimethylvaleronitrile. A catalyst or the like is used. Further, the reaction temperature can be appropriately selected from the temperature range known to those skilled in the art.

In such polymerization, other unsaturated monomers copolymerizable with the monomers other than the above-mentioned two components, such as alkyl vinyl ether, methacrylamide, ethylene, propylene, and α, unless the purpose of the present invention is impaired. −
Olefin such as hexene, α-octene, α-dodecene, α-octadodecene, nitriles such as acrylonitrile and methacrylonitrile, alkyl acrylate, alkyl methacrylate, alkyl crotonic acid, dialkyl maleate, dialkyl itaconate A small amount of ester, citraconic acid dialkyl ester, fumaric acid dialkyl ester and the like may be copolymerized.

The copolymer obtained by such a method is then saponified. As the saponification method, any method such as kneader saponification, continuous saponification, and pearl saponification can be adopted. In the saponification step, the residual monomer is expelled as necessary, and then saponification is performed according to a conventional method. To be done. Examples of the catalyst used for saponification include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, sodium methylate, sodium ethylate and potassium methylate, alkali catalysts such as alcoholate, sulfuric acid, hydrochloric acid and the like. An acid catalyst is used. The saponification reaction temperature is not particularly limited and is usually selected from the range of 10 to 60 ° C, preferably 20 to 50 ° C, and the saponification reaction is 5 to 24 ° C.
It takes place over 0 minutes. Neutralize after the saponification reaction,
The desired modified PVA-based resin can be obtained by washing with alcohol or the like and drying if necessary. Next, a method of molding a molded product using the obtained modified PVA-based resin will be described.

The modified PVA resin can be used alone or in combination with other resins. The modified PV
As a method of molding the A-based resin alone, a known PVA-based resin molding method can be adopted. For example, a casting method, a casting method, or the like can be adopted. When these molding methods are performed, the PVA-based resin is subjected to molding as an aqueous solution of 1 to 50% by weight to obtain a molded product such as a film or a sheet. Of. The modified PVA-based resin of the present invention is also very useful when used in combination with other resins. Examples of other resins include polyamide-based resins, polyolefin-based resins, polyester-based resins, polyvinyl chloride-based resins and the like. Hydrophobic resins are mentioned.

The mixing ratio of the PVA-based resin and the hydrophobic resin cannot be generally determined depending on the kind of the hydrophobic resin, but usually 50-100,000 of the hydrophobic resin is added to 100 parts by weight of the PVA-based resin. It is selected from the range of parts by weight. When blending the PVA-based resin and the hydrophobic resin, a method of dry blending a predetermined amount of each of them and a method of melt blending are possible. When the hydrophobic (thermoplastic) resin as described above is used in combination, melt molding is possible, and examples of the melt molding method include an injection molding method, an extrusion molding method and a transfer molding method. The extrusion molding method includes blow molding, inflation molding, coextrusion molding, extrusion coating and the like.

The injection conditions are preferably set within a range of, for example, a cylinder temperature of 150 to 250 ° C., a mold temperature of 10 to 100 ° C., and an injection pressure of 500 to 2000 kg / cm ² , and extrusion conditions such as a die. Temperature 1
It is preferable that the temperature is set to about 50 to 250 ° C. and the screw compression section temperature is set to a temperature about 5 to 30 ° C. higher than the discharge section temperature. The molded product of the present invention obtained by such a method has a
Compared to PVA-based resin, it has excellent mechanical strength, and when used in combination with other hydrophobic resins, it does not reduce the mechanical strength of other hydrophobic resins and is excellent in molding processability. , It is very useful for applications such as film, sheet, pipe, tube, drip-proof film, temporary film, and water-soluble fiber for chemical lace.

[0019]

Since the molded product of the present invention uses a specific modified PVA-based resin, the modified PVA-based resin alone has excellent mechanical strength as compared with other (modified) PVA-based resins. When used in combination with other hydrophobic resins, it does not reduce the mechanical strength of other hydrophobic resins and has excellent moldability, and can be used for fibers, films, sheets, pipes, tubes,
Very useful for applications such as drip-proof coatings, temporary coatings, and water-soluble fibers for chemical lace.

[0020]

EXAMPLES The present invention will be specifically described below with reference to examples. In the examples, "%" and "parts" mean weight basis unless otherwise specified. (Production of modified PVA resin) 500 parts of maleic anhydride,
65.9 parts of diisobutylamine was charged into a flask, and the reaction was carried out at 60 ° C. for 2 hours while stirring. After completion of the reaction, the reaction product was recrystallized to obtain the compound represented by Chemical formula 4.

[Chemical 4] R ₀ is shown in Chemical formula 5.

Embedded image The yield was 95%.

A polymerization vessel equipped with a reflux condenser, a dropping funnel, and a stirrer was charged with 1,000 parts of vinyl acetate and 150 parts of methanol, and the temperature was raised under a nitrogen stream while stirring to obtain 0.6 of azobisisobutyronitrile at 62 ° C. A solution prepared by dissolving 1 part in 19.4 parts of methanol was added to initiate polymerization.
Polymerization was performed while continuously adding dropwise 272 parts of a methanol solution containing 27.2 parts of the compound N, N-diisobutylmaleic acid monoamide obtained above from the polymerization initiation point over 5 hours while the vinyl acetate ester polymerization rate was 50%. The polymerization was terminated when the percentage reached. Then, the unreacted vinyl acetate monomer was removed out of the system by a method of blowing methanol vapor to obtain a methanol solution of the copolymer. Then, the solution was diluted with methanol to adjust the concentration to 30% and charged in a kneader, and sodium hydroxide was added to neutralize while keeping the solution temperature at 35 ° C.

To this, sodium hydroxide was further added in an amount of 30 mmol based on the vinyl acetate unit in the polymer and kneaded. As the saponification reaction proceeded, a saponified product was deposited and finally became a particulate form. The resulting modified PVA-based resin was filtered, washed well with methanol, and dried in a hot air drier to obtain the desired product. The modified PVA resin thus obtained was extracted and washed with methanol using a Soxhlet extractor, and the degree of modification with diisobutyl maleic acid monoamide was analyzed by ¹ H-NMR. As a result, the degree of modification was 2.0 mol%. In addition, modified PVA
The saponification degree of the system resin was 90 mol% when analyzed by quantifying the amount of alkali consumption required for hydrolysis of the residual vinyl acetate unit. The viscosity of the 4% aqueous solution of the modified PVA-based resin measured by a B-type viscometer is 30 cps / 20 ° C.
Met.

Further, the IR spectrum and ¹ H-NMR (D ₂ O) spectrum of the obtained modified PVA resin are shown below. ^{IR: 3350cm -1, 1100cm -1 -OH} 2950cm -1, 1420cm -1 -CH 1650cm -1 -C = O 1585cm -1 COONa 1 H-NMR: 0.9ppm -CH (CH 3) 2 methyl protons Methyl protons of 2.1ppm -O-CO-CH ₃ Example 1 After preparing a 10% aqueous solution of the above-mentioned modified PVA-based resin, the aqueous solution was poured onto a glass plate to prepare a film having a dry thickness of 100 μm. Then, the film was punched out into a No. 3 dumbbell and subjected to mechanical strength (tensile strength) at 20 ° C. and 65% RH with an Autograph IM-1100 type (load cell 5 kg, pulling speed 100 mm / min) manufactured by Shimadzu Corporation. , Elongation) was measured.

Examples 2 to 7 and Comparative Examples 1 to 6 Ethylenically unsaturated dicarboxylic acid monoamides were synthesized under the components and conditions shown in Table 1 and various ethylenically unsaturated dicarboxylic acid monoamides and vinyl acetate were obtained. The copolymerization of the above (modified PVA with the components and charging amounts shown in Table 2)
The production of various modified PVA-based resins shown in Table 3 by copolymerization with vinyl acetate (in Comparative Example 6 without adding a modifying monomer) and saponification by the same procedure as in (Production of resin). Then, a film was produced using the PVA-based resin in the same manner as in Example 1, and the mechanical strength was measured in the same manner as in Example 1. Table 4 shows the evaluation results of the examples and the comparative examples.

[0025]

[Table 1]Conditions for the synthesis of ethylenically unsaturated dicarboxylic acid monoamides Synthetic monoamido acid Amine temperature Time yield(Part) (Part) (℃) (hr) (%) Di-BMMAm Diisobutylamine maleic acid 60 295 Di-BIMAm Itaconic anhydride Diisobutylamine 60 295 Di-AMMAm Maleic anhydride Diisoamylamine 60 2 97 D-EHMMAm Maleic anhydride Di (2 ethylhexyl) amine 60 292 Dn -DMMAm Maleic anhydride Di-n-propylamine 60 295Nn-OMMAm maleic anhydride n-octylamine 60 290  Note) The abbreviations are as follows. D-i-BMMAm; N, N-diisobutyl maleic acid monoamide D-i-BIMAm; N, N-diisobutylitaconic acid monoamide D-i-AMMAm; N, N-diisoamyl maleic acid monoamide D-EHMMAm; N, N -Di (2 ethylhexyl) maleic acid monoamide D-n-DMMAm; N, N-di-n-propyl maleic acid monoamide N-n-OMMAm; N-n-octyl maleic acid monoamide

[0026]

[Table 2] Type of monomer copolymerized with vinyl acetate, charged amount and polymerization rate (A) Monomer Polymerized rate type Charged amount (mol%) (%) Example 1 D-i-BMMAm 2. 0 50 〃 2 D-i-BMMAm 0.5 60 〃 3 D-i-BMMAm 8.0 47 〃 4 D-i-BIMAm 2.0 50 50 〃 5 D-i-AMMAm 2.0 55 〃 6 D- EHMMAm 2.0 45 〃 7 D-BMMAm 2.0 50 Comparative Example 1 D-n-DMMAm 2.4 53 〃 2 N-n-OMMAm 2.5 52 〃 3 MRM 3.0 55 〃 4 AMPS 2.0 55 〃 5 3M 2.0 60 〃 6 --- 87

Note: The charged amount represents a charged mole fraction (mol%) of the monomer (A) with respect to the total charged amount of the monomers. Abbreviations are as follows. D-i-BMMAm; N, N-diisobutyl maleic acid monoamide D-i-BIMAm; N, N-diisobutylitaconic acid monoamide D-i-AMMAm; N, N-diisoamyl maleic acid monoamide D-EHMMAm; N, N -Di (2 ethylhexyl) maleic acid monoamide D-n-DMMAm; N, N-di-n-propyl maleic acid monoamide N-n-OMMAm; N-n-octyl maleic acid monoamide 3M; monomethyl maleate MRM; mono ( Diisopropylmethyl) malate AMPS; N-sulfoisobutylene acrylamide sodium

[0028]

[Table 3]

The assignments of the IR spectrum and ¹ H-NMR spectrum of the modified PVA-based resins obtained in Examples 2 to 7 are shown below. (Modified PVA-based resin in Example ^{2) IR: 3350cm -1, 1100cm} -1 -OH 2950cm -1, 1420cm -1 -CH 1650cm -1 -C = O 1585cm -1 COONa 1 H-NMR: 0.9ppm - CH (CH ₃ ) ₂ methyl proton Methyl protons of 2.1ppm -O-CO-CH ₃

[0030] (modified PVA-based resin of Example ^{3) IR: 3350cm -1, 1100cm} -1 -OH 2950cm -1, 1420cm -1 -CH 1650cm -1 -C = O 1585cm -1 COONa 1 H-NMR: 0 .9ppm -CH (CH _{3) 2} methyl protons Methyl protons of 2.1ppm -O-CO-CH ₃

[0031] (modified PVA-based resin of Example ^{4) IR: 3350cm -1, 1100cm} -1 -OH 2950cm -1, 1420cm -1 -CH 1650cm -1 -C = O 1585cm -1 COONa 1 H-NMR: 0 .9ppm -CH (CH _{3) 2} methyl protons Methyl protons of 2.1ppm -O-CO-CH ₃

[0032] (modified PVA-based resin of Example ^{5) IR: 3350cm -1, 1100cm} -1 -OH 2950cm -1, 1420cm -1 -CH 1650cm -1 -C = O 1585cm -1 COONa 1 H-NMR: 0 .9ppm -CH ₂ -CH ₃ methyl protons Methyl protons of 2.1ppm -O-CO-CH ₃

[0033] (modified PVA-based resin of Example ^{6) IR: 3350cm -1, 1100cm} -1 -OH 2950cm -1, 1420cm -1 -C-H 1650cm -1 -C = O ( amide I absorption band) 1585 cm ^{- 1 -COONa 1 H-NMR: 0.9ppm} -CH 2 -CH 3 methyl protons Methyl protons of 2.1ppm -O-CO-CH ₃

[0034] (modified PVA-based resin of Example ^{7) IR: 3350cm -1, 1100cm} -1 -OH 2950cm -1, 1420cm -1 -C-H 1650cm -1 -C = O ( amide I absorption band) 1585 cm ^{- 1 -COONa 1 H-NMR: 0.9ppm} -CH (CH 3) 2 methyl protons Methyl protons of 2.1ppm -O-CO-CH ₃

[0035]

[Table 4]

Examples 8 to 11 The modified PVA resin used in Example 1 was blended with hard polyvinyl chloride and nylon 12 as shown in Table 5, and melt-molded to prepare a film having a thickness of 100 μm. Then, the mechanical strength (tensile strength, elongation) and moldability of the film were examined. The evaluation results are also shown in Table 5. Table 5 also shows the mechanical strength (tensile strength, elongation) and moldability when using each of the rigid polyvinyl chloride and nylon 12 alone as Reference Examples 1 and 2. The method for measuring the mechanical strength was in accordance with the method of Example 1, and for moldability, it was examined whether or not a film having a thickness of 30 μm can be formed by melt extrusion with a T die at 200 to 210 ° C.

[0037]

TABLE 5 Mechanical strength moldability hydrophobic resin blend ratio tensile strength elongation (by weight) of the blend composition film (kg / cm ²⁾ (%) Reference Example 1 PVC 100/0 480 14 moldable Example 8 PVC 100/10 465 13 Moldable 〃 9 PVC 100/20 455 13 Moldable Reference Example 2 NY12 100/0 451 233 Moldable Example 10 NY12 100/10 440 215 Moldable 〃 11 NY12 100/20 425 200 Moldable Note ) PVC represents rigid polyvinyl chloride, NY12 represents nylon 12, and the blending ratio represents hydrophobic resin / modified PVA-based resin.

[0038]

EFFECTS OF THE INVENTION Since the molded product of the present invention uses a specific modified PVA-based resin, the modified PVA-based resin alone has excellent mechanical strength as compared with other (modified) PVA-based resins. In addition, when used in combination with other hydrophobic resin, it is excellent in molding processability without deteriorating the mechanical strength of other hydrophobic resin, and can be used for fibers, films, sheets, pipes, tubes, drip-proof films, Very useful for applications such as temporary coatings and water-soluble fibers for chemical lace.

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[Procedure amendment]

[Submission date] April 21, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

Embedded image Here, R ₀ is shown in Chemical formula 2.

Embedded image (However, n is 1 to 3, R _{1 to} R ₃ are each hydrogen or an alkyl group or an aryl group, and two or more are not hydrogen at the same time, and the total number of carbon atoms of R _{1 to} R ₃ is 4 That is all.)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C08L 27/06 LET C08L 27/06 LET 67/00 LPB 67/00 LPB 77/00 LQS 77/00 LQS

Claims (2)

[Claims] 1. A polyvinyl alcohol polymer containing 0.1 to 20 mol% of an ethylenically unsaturated dicarboxylic acid monoamide (A) as a copolymerization component, the amide component of the ethylenically unsaturated dicarboxylic acid monoamide (A). Is a polyvinyl alcohol-based resin represented by the following chemical formula 1. Embedded image Here, R ₀ is shown in Chemical formula 2. Embedded image (However, n is 1 to 3, R _{1 to} R ₃ are each hydrogen or an alkyl group or an aryl group, and two or more are not hydrogen at the same time, and the total number of carbon atoms of R _{1 to} R ₃ is 4 That is all.) 2. The molded product according to claim 1, wherein the hydrophobic resin is at least one selected from a polyamide resin, a polyolefin resin, a polyester resin, and a polyvinyl chloride resin.