JPH03163109A - Preparation of water-soluble thermoplastic resin - Google Patents

Abstract

PURPOSE:To prepare the title resin which is melt moldable and gives a film excellent in the physical properties by modifying a maleic anhydride copolymer with a polyoxyalkylene glycol monoether. CONSTITUTION:A maleic anhydride copolymer (pref. a copolymer having a mol.wt. of 1000-1000000 and obtd. by copolymerizing one mol of maleic anhydride with one mol or higher of an alpha-olefin, esp. isobutylene) is estrified with a polyoxyalkylene glycol monoether of RO(AO)nH (wherein R is 1-10C alkyl; A is 2-4C vic-alkylene; and n>=1, pref. 100>n>=1, still pref. 50>n>=1) to give the title resin, which is useful for a hot-melt binder, water-base binder, adhesive, thread, film, fibrous molded product, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing a thermoplastic water-soluble resin by adding polyoxyalkylene glycol monoether to a maleic anhydride copolymer. [Prior Art] Conventionally, there has been known a method for producing a maleic anhydride copolymer by copolymerizing maleic anhydride with an α-olefin such as ethylene, isobutylene, diisoptylene, or a vinyl compound such as styrene or methyl vinyl ether. There is. Maleic anhydride copolymers are mainly used as water-soluble binders. However, these copolymers have a high softening point, poor hot melt moldability, and are hard and brittle, which limits their use. [Problems to be Solved by the Invention] In view of the above-mentioned current situation, the present invention is capable of melt molding and improves film physical properties by adding polyoxyalkylene glycol monoether to a maleic anhydride copolymer and modifying it. The aim is to provide a method for producing excellent thermoplastic water-soluble resins. [Means for Solving the Problems] According to the present invention, the above problems can be solved by using a maleic anhydride copolymer and the general formula (1) RO(AO)ll}l (1) (wherein R is a carbon number of 1 to 10 is an alkyl group, and A is a vic-alkylene group having 2 to 4 carbon atoms which may be substituted with a phenyl group, and A in each ( ) may be the same or different, and if different, is an ester with a polyoxyalkylene glycol monoether represented by (the same A and different A may be connected in a block manner or randomly through 0, and n is an integer of 1 or more). The problem is solved by a method for producing a thermoplastic water-soluble resin, which is characterized by carrying out a chemical reaction.

The present invention will be explained in detail below.

The maleic anhydride copolymer used in the present invention is a combination of maleic anhydride and carbon-carbon-double bond-containing monomers copolymerizable with alpha-olefins and/or other types of maleic anhydride. It refers to a copolymer produced by a chain reaction through multiple bonds.

The maleic anhydride used may contain some amount of maleic anhydride derivatives such as maleic acid, maleic acid monoalkyl ester, maleic acid dialkyl ester, chloromaleic acid, and citraconic acid. The content of these derivatives is not particularly limited, but is usually up to 80% (w/w).

The α-olefin herein means a linear or branched olefin having a double bond at the 1-position, such as ethylene, brobylene, 1-butene, isobutylene, ■-pentene, 2-methyl-l-butene, 1-hexene, 2-
Methyl-1-pentene, 3-methyl-1-bentene, 2
-Ethyl-1-butene, diisobutylene, etc. with 2 or more carbon atoms
12, preferably 2 to 8 α-olefins are included.

These α-olefins may be used alone or in combination of two or more. The thermoplastic water-soluble resin of the present invention obtained by modifying the isoptylene-maleic anhydride copolymer has a high heat distortion temperature and thermal decomposition temperature, and has excellent strength, so it is particularly preferable to use isobutylene.

Other types of carbon-carbon/double bond-containing monomers copolymerizable with maleic anhydride used here include styrene,
Vinyl compounds such as alkyl-substituted styrene, vinyl ether, vinyl ester, vinyl halide, allyl ether, allyl alcohol, allyl ester, acrylonitrile, acrylic ester, methacrylic ester, acrylic amide, methacrylic amide, isobrene, butadiene, etc. Dienes, maleimide, N-monosubstituted male ξ
An example is de. These monomers can be used alone or in combination of two or more, and further in combination with α-olefin. The copolymer composition molar ratio of the maleic anhydride copolymer used in the present invention is maleic anhydride (as a whole if it contains a maleic anhydride derivative)
1 mole of alpha-olefin or other type of monomer
~5 mol is appropriate. If it is less than 1 mol, the thermoplasticity of the copolymer will be poor, and if it is more than 5 mol, the water solubility of the copolymer will be reduced. Even when a mixture of α-olefin and other types of monomers is used, the total amount may be within the above value.

The molecular weight of the maleic anhydride copolymer is not particularly limited, but may be within a range in which the physical properties of the thermoplastic water-soluble resin obtained by the present invention, such as heat molding processability, strength of molded products, and flexibility, are appropriate. 1,000 to 1,000,000 is preferable.

The maleic acid copolymer used in the present invention can be obtained by copolymerizing the above-mentioned α-olefin and/or other types of monomers with maleic anhydride using a radical catalyst. The maleic acid copolymer used in the present invention is partially known, and also by known methods (for example, Japanese Patent Publication No. 53-38
No. 095), the above-mentioned α-olefin and/or other types of monomers are copolymerized with maleic anhydride using a radical catalyst. In summary, the radical polymerization catalysts used in such copolymerization include organic peroxides such as kiemene hydroperoxide, t-butylhydroperoxide, and penzoyl peroxide, α. α′-azobisisobutyronitrile, α,α′-azo α-ethylbutyronitrile,
Azo compounds such as α, α′-azo α-methylvaleronitrile are commonly mentioned. Polymerization is carried out by solution polymerization or precipitation polymerization using a solvent that does not inhibit radical polymerization, such as acetone, methyl ethyl ketone, benzene, toluene, ethyl acetate, isopropyl acetate, dioxane, tetrahydrofuran, or chloroform. Do not use. It is also possible to carry out bulk polymerization. Polymerization temperature is not particularly limited, but is usually 0 to 20.0
℃ range, and the polymerization time is also usually in the range of 1 to 50 hours. Separation of the maleic anhydride copolymer from the polymerized solution is carried out in the case of precipitation polymerization by filtering and removing the liquid from the precipitated polymer and drying, or in the case of solution polymerization by expelling the solvent and drying. The polyoxyalkylene glycol monoether of the general formula ([), which is the other raw material of the present invention, has 1 to 1 carbon atoms.
In the presence of a chlorine catalyst such as potassium hydroxide, sodium hydroxide, pyridine, picoline, or 2-methylimidazole, or an acid catalyst such as boron trifluoride or tin tetrachloride, even if a phenyl group is substituted with the alkanol of 0. Good carbon number 2
Obtained by addition reaction of ~1o vic-alkylene oxide. Furthermore, alkanol having 1 to 10 carbon atoms and Li%K% Has IIlg, Zns Art s
A polyoxyalkylene glycol monoether of the general formula (■.) can also be obtained by polymerizing a vic-alkylene oxide having 2 to 10 carbon atoms using an alcoholate with Sn or Fe as an initiator. Examples of alkanols having 1 to 10 carbon atoms used in the present invention include methanol, ethanol, propanol, butanol, heptanol, nonanol, decanol, etc. Examples of alkylene oxide include ethylene oxide, propylene oxide, 1,2-epoxybutane, 1.
Examples include 2-epoxypenkune and styrene oxide. The addition reaction of alkylene oxide to alcohol proceeds almost stoichiometrically, yielding a polyoxyalkylene glycol monoether whose average number of added moles is the molar ratio of added alkylene oxide to alcohol. There is no strict upper limit for on in the above general formula (1), but if it is too large, the addition reaction of ethylene oxide will take a long time, and the resulting polyoxyalkylene glycol monoether and maleic anhydride copolymer will Since the ester reaction is also slow, the catalyst is preferably an integer of about 100 or less, more preferably about 50 or less. 1 to 5% by weight is appropriate. Solvents are usually not required, but solvents without active hydrogen, such as acetone, tetrahydrofuran,
It may be diluted with dioxane, etc. The reaction is usually 30-15
It is appropriate to carry out the test at 0°C for 1 to 30 hours. After the reaction, if there is no unreacted alkylene oxide remaining in the reaction solution, the reaction solution containing polyoxyalkylene glycol monoether can be used as it is for the esterification reaction, and if there is no unreacted alkylene oxide left in the reaction solution. If any alkylene oxide remains, it is preferable to remove the alkylene oxide by distillation before use. The thermoplastic water-soluble resin of the present invention can be obtained by adding polyoxyalkylene glycol monoether of general formula (I) to a maleic anhydride copolymer in an esterification reaction. As for the esterification conditions, it is preferable to charge the maleic anhydride copolymer and the esterification catalyst into polyoxyalpylene glycol monoether diluted with an organic solvent if necessary, and heat and stir the mixture. Note that the esterification referred to in the production method of the present invention is half-esterification. Suitable esterification catalysts include acid catalysts such as formic acid and p-}luenesulfonic acid, or basic catalysts such as tertiary ammonium, pyridine, and imidazole compounds. The amount of the esterification catalyst used is 0.1 to 3% by weight in the case of an acid catalyst and 0.1% by weight in the case of a basic catalyst based on the maleic anhydride copolymer.
~5% by weight is appropriate. When used, suitable solvents are those that dissolve both the raw material compound system and the product compound, such as dimethylformamide, acetone, and tetrahydrofuran.

If the degree of esterification is too small, the resulting esterified product will have insufficient thermoplasticity, so it is appropriate that 5% or more, especially 8% or more, of the maleic anhydride groups in the copolymer be esterified. .

The reaction temperature varies depending on the type of maleic anhydride copolymer and polyoxyalkylene glycol monoether used, but is generally preferably 50 to 200°C. A suitable reaction time is 1 to 30 hours.

After the esterification reaction is completed, the unreacted polyoxyalkylene glycol monoether and the solvent used are removed by distillation to obtain the thermoplastic water-soluble citrus resin of the present invention as a residue.

The thermoplastic water-soluble resin produced by the method of the present invention has various physical properties (
softening point, melt viscosity, film strength, and water solubility), but it is generally melt moldable and has excellent film properties.

Such thermoplastic water-soluble resins include hoftmelt binders,
Possible applications include water-based binders, absorbent compositions, polymer alloys, dispersants, and adhesives, and it can also be used in the form of threads, films, and fibers.

Although it is generally difficult to structurally represent the thermoplastic water-soluble resin obtained by the method of the present invention, for example, when the maleic anhydride copolymer is a copolymer consisting of maleic anhydride and isoptylene, , acid group) and 1 GHz
5 of the maleic anhydride groups of the maleic anhydride copolymer at a ratio of 1 to 5 mol of the latter structural unit per 1 mol of the former structural unit consisting of the structural unit represented by C(CI3)t-.
% or more can be expressed as a copolymer half-esterified with polyoxyalkylene glycol monoether of general formula (I). Similarly, when the maleic anhydride copolymer is a copolymer consisting of maleic anhydride and ethylene or styrene, the above
The structural unit represented by -CUt -CHt- or -C
It can be expressed as a copolymer in which the structural unit represented by Ht - CH (ph) is replaced. In addition, in the case of a copolymer consisting of maleic anhydride, N-phenylmaleimide, and isobutylene, the maleic anhydride copolymer of the first example is added to 1 mole of the former structural unit consisting of the structural unit with pH. On the other hand, it can be expressed as a copolymer in which the latter structural units are replaced with a maleic anhydride copolymer in a total proportion of 1 to 5 moles.

〔Example〕

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited thereto.

Example: 64 g of methanol and 0.0 g of 2-methylimidazole in an autoclave. After charging 32 g and replacing with nitrogen, 6
Addition reaction was carried out for 10 hours by gradually pressurizing 528 g of ethylene oxide at 0 to 80°C. After the reaction is complete, the remaining unreacted ethylene oxide is removed by distillation, and the average number of added moles of ethylene oxide is 6 (according to gel permeation chromatography (GPC) analysis, from n = 4 centered on n-6). 8) of polyoxyethylene glycol monomethyl ether was obtained.

Next obtained polyoxyethylene glycol monomethyl ether 1 7. 8 g, isobutylene-maleic anhydride copolymer with a weight average molecular weight of 50,000 (isoban 04,
■Kuraray) (Copolymerization molar ratio isoptylene:maleic anhydride = 1:1) 30.8g, 2-methylimidazole 0.50g, and dimethylformamide (DMF)
) was charged into a three-necked flask equipped with a reflux condenser, and stirred and heated at 80 to 90° C. for 5 hours under a N2 gas stream to perform an esterification reaction.

When the unreacted polyoxyethylene glycol monomethyl ether in the reaction-completed solution was quantified by GPC using PPG (polybropylene glycol) as an internal standard, an average reaction rate of polyoxyethylene glycol heptamethyl ether of 50% was obtained. Ta. DM by holding the reaction completed solution at 120°C under reduced pressure.
F and unreacted polyoxyethylene glycol monomethyl ether were distilled off to obtain a partial ester of isobutylene-maleic anhydride copolymer with polyoxyethylene glycol monomethyl ether 9. 5 g was obtained. The structure of the obtained partially esterified product was confirmed by elemental analysis, acid value, and infrared absorption spectrum measurements.

Elemental analysis C: 59.8% (theoretical value 60.2%) H: 7
．． 3% (theoretical value 7.2%) Acid value 519■KOH/g (theoretical value 523■K
OR/g), that is, the esterification rate was 14.9%.

Infrared absorption spectrum 3550cm-' ν01I (carboxylic acid) 1
750aa-' νC. O (ester, carboxylic acid) 186'0.1800al-' pc-0 (maleic anhydride group) 1120 value-1 νC10 (ether bond) Next, the obtained partial ester compound was heated at 150°C
A transparent sheet with a thickness of 1 nm was produced by heat pressing for 3 minutes at a pressure of 50 kg/cs"G. The softening point of this sheet was measured to be 120°C, and a tensile test using an Instron (tensile speed 50 m/win), the breaking strength was 8 Q kg/am''G and the breaking elongation was 30%. Furthermore, 10 g of the obtained ester compound, 6.34 g of 25% Nus water, and 50 g of water were charged into a three-necked Fudesco equipped with a reflux condenser, and when heated and stirred at 50 to 60°C for 30 minutes, a transparent aqueous solution was obtained. Ta.

It should be noted that the isoptylene-maleic anhydride copolymer used as a raw material had no thermoplasticity and could not be shaped into a certain shape by heat pressing. This fact was also true for the raw material maleic anhydride copolymer used in the following examples. 1 1N autoclave and 4 ethanol 6. 1 g and 2
- After charging 0.5 g of methylimidazole and replacing with nitrogen,
440 g of ethylene oxide was gradually introduced under pressure at 70 to 90°C and the addition reaction was carried out for 10 hours. polyoxyethylene glycol monoethyl ether t- obtained t-
;． Next, the obtained polyoxyethylene glycol monoethyl ether 2 9. 2 g, imptylene-maleic anhydride copolymer with a weight average molecular weight of 150,000 (isoban IO,
■Kuraray) (copolymer composition molar ratio isoptylene:maleic anhydride-1:1) 30.8g, 0.50g of 2-methylidazole, and 150g of DMF were charged into a three-necked flask equipped with a reflux condenser, and N2 Lower 100-120
The mixture was stirred and heated at ℃ for 6 hours to carry out the esterification reaction.

Based on the amount of unreacted polyoxyethylene glycol monoethyl ether in the reaction-completed solution, the average reaction rate of polyoxyethylene glycol monoethyl ether was 30%. The reaction completed liquid was poured into a large amount of water to precipitate the polymer, unreacted polyoxyethylene glycol 7-ethyl ether 5 and DMF were removed, and the mixture was dried under reduced pressure at 80°C.
39.0 g of an isoptylene-maleic anhydride copolymer partially esterified with polyoxyethylene glycol monoethyl ether (esterification rate 10%) was obtained.

The obtained partially esterified product was heated at 150°C x 50 kg/■2
Heat press for 3 minutes under G condition to a thickness of 0. 5tm
A transparent sheet was created. The softening point of this sheet is 10
0℃, and the breaking strength in a tensile test is 20 kg.
/cs"G, and the elongation at break was 350%.

Furthermore, 20 g of the obtained esterified product, 5% NHs water
．． When stirring and heating 15 g of 15 g and 100 g of water at 50°C for 10 minutes, a transparent aqueous solution was obtained. 1 g
and 0.7 g of 2-methyl ξdazole, and after purging with nitrogen, heated to 90-100°C. Then, 264 g of ethylene oxide was gradually added to carry out an addition reaction for 15 hours to obtain boroxyethylene glycol monobutyl ether having an average number of added moles of ethylene oxide of 6.

27.1 g of polyoxyethylene glycol monobutyl ether thus obtained, weight average molecular weight 45,000 (G
Isobutylene-maleic anhydride mono-N (according to PC analysis)
- Phenylmaleimide copolymer (copolymer combination molar ratio of isobutylene:maleic anhydride:N-phenylmaleimide -0.52:0.42:0.0B) 3 5.
2 g, 1.0 g of pyridine, and 100 g of acetone were placed in a three-necked flask equipped with a reflux condenser, and heated under N2 for 80~
Esterification reaction was carried out by heating and stirring at 100°C for 4 hours. The reaction rate of polyoxyethylene glycol monobutyl ether was 45% from the analysis results of the reaction completed liquid.

DM by holding the reaction completed solution at 120°C under reduced pressure.
F and unreacted polyoxyshetylene glycol monobutyl ether are distilled off to obtain isobutylene-maleic anhydride-
Partial esterification product of N-phenylmale ξ-do copolymer with polyoxyethylene glycol monobutyl ether 4 6. 8 g was obtained. Next, the obtained partially esterified product (esterification rate 20%
) was heat pressed for 5 minutes at 150°C x 5 Q kg/cm"G to produce a sheet with a thickness of 1 nm. The softening point of this sheet was 100°C, and the breaking strength in a tensile test was 60 kg/cm"G. cu2G, the elongation at break was 50%. Also, 20 g of the esterified product, 6.2 g of 25% NH3 water
When 50 g of water was stirred and heated at 70 to 80°C for 30 minutes, a transparent aqueous solution was obtained.

The isoptylene-maleic anhydride mono-N-phenylmaleimide copolymer was produced as follows: 250 g of ethyl acetate. ．． t-7' thyl alcohol 110
g, 29.4 g of maleic anhydride, 9.9 g of N-phenylmaleimide, and 0.9 g of α,α'-azobisisobutyronitrile. 60 g of isobutylene was placed in an If autoclave equipped with a stirrer, and after stirring and purging with nitrogen for 30 minutes, 2.2 g of isobutylene was added. 0 g and the solution inside the autoclave is 80 g.
After raising the temperature to 80°C, the temperature was maintained at 80°C for 6 hours to carry out a polymerization reaction. After the polymerization reaction is completed, the autoclave solution is cooled to room temperature and degassed, and the contents are taken out from the autoclave, and the precipitated polymer is filtered and dried to obtain isobutylene/maleic anhydride/N-phenylmaleimide ternary copolymer 5. 7.
9 g was obtained. The weight average molecular weight and copolymer composition of this terpolymer were as described above.

26.71 g of polyoxyethylene glycol monomethyl ether with an average added mole number of ethylene oxide of 6, obtained in the same manner as in Example 1, and an ethylene-maleic anhydride copolymer (EMA21) with a weight average molecular weight of 25,000. , Monsando) (copolymer composition molar ratio ethylene:maleic anhydride = 1:1) 37.86 g, 2-methylimidazole 0. 40 g and 120 g of DMF were placed in a three-necked flask equipped with a reflux condenser, and
Esterification reaction was carried out by stirring and heating at OO°C for 6 hours.

The reaction rate of polyoxyethylene glycol monomethyl ether was 58% based on the analysis value of unreacted polyoxyethylene glycol monomethyl ether in the reaction completed liquid.

DM by holding the reaction-completed solution at 120°C under vacuum.
F and unreacted polyoxyethylene glycol monomethyl ether were distilled off to obtain a partial esterification product of ethylene-maleic anhydride with polyoxyethylene glycol monomethyl ether (esterification rate 17.5%) 52.2
8g was obtained.

Next, the obtained partially esterified product was weighed at 150°C x 50 kg.
/ Heat pressed for 5 minutes under the conditions of CIlχG to a thickness of 1
I created a sheet of n. The softening point of this sheet is 80℃, and the breaking strength in a tensile test is 30kg/c.
The elongation at break was 80%. When 20 g of the esterified product and 100 g of water were heated at 70 to 80° C. for 1 hour, a transparent aqueous solution was obtained.

18.70 g of polyoxyethylene glycol monomethyl ether with an average number of added moles of ethylene oxide of 6, obtained by the same method as in Example 1, weight! Styrene-maleic anhydride copolymer with an average molecular weight of 6,000 (copolymerization & Iltc molar ratio -121 (NMR analysis) 42.48 g, 2-methyligodazole 0.40 g and DMF 120 g
into a three-necked flask equipped with a reflux condenser, 95~
Esterification reaction was carried out by stirring and heating at 105° C. for 6 hours.

The reaction rate of polyoxyethylene glycol monomethyl ether was 49% based on the analysis value of unreacted polyoxyethylene glycol monomethyl ether in the reaction completed liquid. I) by holding the reaction-completed solution at 120°C under vacuum.
MF and unreacted polyoxyethylene glycol monomethyl ether were distilled off to obtain a partially esterified product of ethylene-maleic anhydride copolymer with polyoxyethylene glycol monomethyl ether (esterification rate 14.6%).
) 51.25g was obtained.

Next, the obtained partially esterified product was heated at 150°C x 5 Q k
A sheet with a thickness of 1 am was made by heat pressing for 5 minutes under the conditions of
It was 0℃. In addition, 20 g of the esterified product, 125% N
'Hs water 5. When Og and 50 g of water were stirred and heated at 70-80°C for 30 minutes, a transparent aqueous solution was obtained. Add 48g of methanol and 1g of NaOH to the autoclave.
After purging with nitrogen, 522.9 g of propylene oxide was gradually added at 90 to 100°C to carry out an addition reaction for 15 hours to obtain polyoxypropylene glycol monomethyl ether with an average number of added moles of propylene oxide of 6.

Next, 34.25 g of polyoxypropylene glycol monomethyl ether was obtained, an isoptylene-maleic anhydride copolymer (isoban 0 4) having a weight average molecular weight of 50,000.
46.26g, 2-methylidazole 0. 5
0 g and 150 g of DMF were charged into a three-necked flask equipped with a reflux condenser, and stirred and heated at 90 to 100°C for 6 hours to perform an esterification reaction. The reaction rate of polyoxypropylene glycol monomethyl ether was 57% based on the analysis value of unreacted polyoxypropylene glycol monomethyl ether in the reaction completed liquid.

The reaction completed solution is maintained at 120°C under vacuum to DM.
F and unreacted polyoxypropylene glycol monomethyl ether were distilled off to obtain a partial esterification product of isoptylene-maleic anhydride copolymer with polyoxypropylene glycol monomethyl ether (esterification rate 17%).
) was obtained. Next, the obtained partially esterified product was heated to 150°C.
A sheet with a thickness of 11 was produced by heat pressing for 5 minutes at 50 kg/cs.
kg/cs+”G, and the elongation at break was 90%.
20g of the esterified product, 25% NH, 6.0g of water, 5g of water
When 0g was stirred and heated at 70°C for 2 hours, a transparent aqueous solution was obtained.

1st group 1 ll autoclave was charged with 163 g of polyoxyethylene glycol monomethyl ether with an average number of added moles of ethylene oxide of 3, and 0.5 g of NaOH.
After nitrogen substitution, propylene oxide 17 at 90-100℃
4 g was gradually charged and an addition reaction was carried out for 10 hours (average number of moles of propylene oxide added: 3) to produce polyoxyethylene/polyoxypropylene glycol monomethyl ether in which polyoxyethylene groups and polyoxypropylene groups were added in block form. Obtained. Next, 30.33 g of monomethyl ether obtained, 46.26 g of isoptylene-maleic anhydride copolymer (isoban 04) having a weight average molecular weight of 50,000, and 2-methyl ξ
1.50 g of Dazole was charged into a three-necked flask equipped with a reflux condenser, and the mixture was stirred and heated at 90 to 100° C. for 6 hours to perform an esterification reaction. The reaction rate of the seven-methyl ether was 43% based on the analysis of unreacted monomethyl ether in the reaction-completed solution.

DM by holding the reaction completed solution at 120°C under vacuum.
F and monomethyl ether were distilled off to obtain a partially esterified product of isobutylene-maleic anhydride copolymer. Next, the obtained partially esterified product (esterification rate 12.8
%) to 150'CX50kg/crm'' (.5
A sheet with a thickness of 1 m was produced by heat pressing for 1 minute. This sheet. The softening point is 115℃, the breaking strength in a tensile test is 45kg/cm"G, and the breaking elongation is 65%.
Met. In addition, 20 g of the esterified product, 25% NHs
Water 6. When Og and 50 g of water were stirred and heated at 70° C. for 1 hour, a transparent aqueous solution was obtained.

Lost Storm I Polyoxyethylene glycol monomethyl ether 2 with n=6 obtained in Example I 9. 6 g, isobane-
04 15.4g, 2-methylidazole 0. 6
0 g and 150 g of dimethylformamide were placed in a three-necked flask equipped with a reflux condenser, and heated to 110 g under a N2 stream.
The esterification reaction was carried out by stirring and heating at ~120°C for 12 hours. The reaction rate of polyoxyethylene glycol 7-methyl ether was 72% based on the analysis value of unreacted polyoxyethylene glycol monomethyl ether in the reaction-completed liquid. DMF and unreacted polyoxyethylene glycol monomethyl ether are removed by holding the reaction completed liquid at 120°C under vacuum, and a partially esterified product (esterified) of inbutylene-maleic anhydride copolymer with polyoxyethylene glycol monomethyl ether is removed. rate 72
%) 36.2g was obtained.

Next, the obtained partially esterified product was heated at 150°C x 50k
Heat press for 5 minutes under the condition of g/cm"G to a thickness of l.
I created the SM sheet. The softening point of this sheet was measured to be 105°C, and a tensile test using Instron (tensile speed 50 m/win) revealed a breaking strength of 55 kg/cm"G and a breaking elongation of 60%.
Met.

Furthermore, 10 g of the obtained esterified product, 25% NH, water 4
．． 5 g and 50 g of water were charged into a three-necked flask equipped with a reflux condenser, and heated and stirred at 50 to 60°C for 30 minutes, to obtain a transparent aqueous solution.

Practical Group E Polyoxyethylene glycol 7-methyl ether 1 with n=3 obtained in the same manner as in Example 1 6. 2g
, Isoban-04 15.4g, 2-Methylated Dazole 0. 50 g and 120 g of dimethylformamide
g into a three-necked flask equipped with a reflux condenser, and heated with N2
The esterification reaction was carried out by stirring and heating at 120 to 130° C. for 24 hours under a stream of air. The reaction rate of polyoxyethylene glycol monomethyl ether was 95% based on the analysis value of unreacted polyoxyethylene glycol monomethyl ether in the reaction completed liquid. Dimethylformamide and unreacted polyoxyethylene glycol monomethyl ether are removed by holding the reaction-completed solution at 120°C under vacuum to obtain a partially esterified product (ester) of isobutylene-maleic anhydride copolymer with polyoxyethylene glycol monomethyl ether. (95% conversion rate) was obtained.

Next, the obtained partially esterified product was heated at 200°C x 50k
A transparent sheet with a thickness of 1 was prepared by heat pressing for 5 minutes under the conditions of ``G/cs''. 50m/win), the breaking strength was 120 kg/an2G, and the breaking elongation was 20.
%Met.

Furthermore, 10 g of the obtained esterified product, 4 g of 25% N113 water, and 50 g of water were charged into a three-necked flask equipped with a reflux condenser, and heated and stirred at 50 to 60°C for 30 minutes.
A clear aqueous solution was obtained.

11.2g of methanol and metallic Na in Inutoyo Oku Retired Emperor 11 autoclave
p. Prepare 15 kg, and after replacing with nitrogen, 1lO~15
696.7 g of ethylene oxide was gradually added at 0°C and the reaction was carried out for 10 hours. After the reaction is complete, take out the contents and
Polyoxyethylene glycol monomethyl ether was obtained in which the average number of added moles of ethylene oxide was 45 (according to CGPC analysis, a mixture of the number of added moles of n=45 and n=37 to 53).

Next, 20.2 g of polyoxyethylene glycol monomethyl ether, 15.4 g of isobane, and 0.0 g of 2-methylimidazole were obtained. 50 g and 140 g of dimethylformamide were placed in a three-necked flask equipped with a reflux condenser, and stirred and heated at 100 to 110° C. for 20 hours under a N2 stream to perform an esterification reaction. The reaction rate of polyoxyethylene glycol monomethyl ether was 92% based on the analysis value of unreacted polyoxyethylene glycol monomethyl ether in the reaction completed liquid.

The dimethylformamide solvent was removed by holding the reaction solution at 80°C under vacuum, and a partial esterification product of isoptylene-maleic anhydride copolymer with polyoxyethylene glycol monomethyl ether and unreacted polyoxyethylene glycol monomethyl were obtained. Mixture of ethers 3 5. 4 g was obtained.

Next, the obtained partially esterified product was heated at 150°C x 50k
A sheet with a thickness of 1 was prepared by heat pressing at g/cn''G for 5 minutes.The softening point of this sheet was 80°C.

In addition, 20 g of the esterified product, 25% NH3 water, 5. Og
When 50 g of water was stirred and heated at 70 to 80° C. for 30 minutes, a transparent aqueous solution was obtained.

〔Effect of the invention〕

The present invention provides a thermoplastic water-soluble resin that can be melt-molded and has excellent film properties.

Re

Claims (1)

[Claims] Maleic anhydride copolymer and general formula RO(AO)_nH (wherein, R is an alkyl group having 1 to 10 carbon atoms, and A is a carbon number optionally substituted with a phenyl group) 2-4 vic
- It is an alkylene group, and the A's in each parenthesis may be the same or different, and if they are different, the same A and different A's may be connected in a block shape through O or randomly connected. 1. A method for producing a thermoplastic water-soluble resin, the method comprising carrying out an esterification reaction with a polyoxyalkylene glycol monoether represented by the formula (n is an integer of 1 or more).