JP2008095090A - Method for producing water-disintegratable block copolymer and water-disintegratable block copolymer obtained by the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a block copolymer usable as a novel plastic material having a rapid decomposability in a large amount of water (water disintegratability) while maintaining a certain form in the air and absorbing a certain amount of moisture content. <P>SOLUTION: A method for producing a water-disintegratable block copolymer comprising a step of reacting (a): (a1) a polyalkylene glycol and/or (a2) an aliphatic polyester having a hydroxy group at both ends obtained by esterification of a polyalkylene glycol and an aliphatic dicarboxylic acid or its anhydride, (b) an aliphatic polyester having a hydroxy group at both ends not including a polyoxyalkylene group, and (c) a chain extending agent having a plurality of functional groups to react with a hydroxy group is provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a water-disintegrable block copolymer and a water-disintegrable block copolymer obtained by the method.

Because of its excellent durability, ordinary plastics are not easily decomposed in a natural environment.
Therefore, from the viewpoint of environmental problems, there is a demand for the development of a plastic that maintains a certain form during use and rapidly decomposes in the natural environment after use.

As a kind of degradable plastics, aliphatic polyesters are conventionally known as plastics having so-called “biodegradability” that are degradable by microorganisms in the natural environment (in many cases in the soil) (see, for example, Patent Document 1). ).
Japanese Unexamined Patent Publication No. 07-304839

  However, these conventional aliphatic polyesters exhibit a certain level of degradation performance in soil and activated sludge, but exhibit sufficient degradation performance for applications that require rapid degradation in the water environment, that is, in water. It wasn't something to do.

  The present invention can be used as a new plastic material that has a constant form in air and can absorb a certain amount of moisture, but has a rapid degradability (water disintegration) in a large amount of water. An object of the present invention is to provide a method for producing a block copolymer.

  As a result of intensive studies to solve the above problems, the present inventors have found that a block copolymer produced by the following specific production method retains a certain form in the air and a certain amount of moisture. The present invention was completed by discovering that it can be used as a new plastic material having rapid degradability (water disintegrating property) in a large amount of water while being able to absorb water.

That is, this invention is a manufacturing method of the water disintegrating block copolymer characterized by making the following (a), (b), and (c) react.
(A): (a1) and / or (a2) below
(A1): Polyalkylene glycol (a2): Aliphatic polyester having hydroxyl groups at both ends obtained by esterification reaction of polyalkylene glycol and aliphatic dicarboxylic acid or anhydride thereof (b): Including polyoxyalkylene group Aliphatic polyester having hydroxyl groups at both ends (c): Chain extender having a plurality of functional groups that react with hydroxyl groups The above (a) has a structural unit represented by the following general formula (1), (b) Preferably has a structural unit represented by the following general formula (2) (however, in the following general formulas (1) and (2), n + m ≧ 3).

  (In the formula (1), n is an integer of 1 or more, l is 0 or 1, A is a structural unit derived from polyalkylene glycol having a number average molecular weight of 300 to 20,000, and G1 has 1 carbon atom. -18 aliphatic hydrocarbon groups.)

  (In the formula (2), m is an integer of 1 or more, k is 0 or 1, E is an aliphatic hydrocarbon group having 1 to 18 carbon atoms, G2 is an oxygen atom or the following general formula (3 ).)

(In Formula (3), G3 is a C1-C18 aliphatic hydrocarbon group.)
(A) is an aliphatic polyester having hydroxyl groups at both ends obtained by esterification reaction of polyethylene glycol and aliphatic dicarboxylic acid or anhydride thereof;
(B) may be polybutylene adipate having hydroxyl groups at both ends, or polyethylene butylene adipate having hydroxyl groups at both ends.

(A) is an aliphatic polyester having hydroxyl groups at both ends obtained by esterification reaction of polyethylene glycol and aliphatic dicarboxylic acid or anhydride thereof;
(B) may be polybutylene succinate having hydroxyl groups at both ends.

The (a), (b) and (c) are preferably reacted in an organic solvent containing a dispersant.
(A) is an aliphatic polyester having hydroxyl groups at both ends obtained by esterification reaction of polyethylene glycol and aliphatic dicarboxylic acid or anhydride thereof;
(B) is a polyethylene carbonate having hydroxyl groups at both ends;
It is preferable to react (a), (b), and (c) in an organic solvent containing a dispersant.

  (A) and (b) are mixed in an amount such that the weight ratio ((a) :( b)) is 100: 1 to 100: 100, and the total amount of (a) and (b) is 100 parts by weight. On the other hand, it is preferable to add 0.5 to 10 parts by weight of (c) for reaction.

It is preferable that the aliphatic dicarboxylic acid is succinic acid.
The dispersant is preferably a resin having a branched polyolefin unit and an aliphatic polyester unit.

The dispersant is preferably at least one resin selected from the group consisting of the following (i) to (iv).
(I) Resin in which hydroxyl group of polyol obtained by dehydration condensation of alkenyl succinic anhydride and polyol is masked (ii) Dehydration condensation of fatty acid on part of residual hydroxyl group of polyester obtained by dehydration condensation of dicarboxylic acid and pentaerythritol (Iii) After graft-polymerizing an ethylenically unsaturated monomer to a resin in which a part of the hydroxyl group of the polyol obtained by dehydration condensation of an unsaturated bond-containing dicarboxylic acid and the polyol remains, the remaining hydroxyl group Masked resin (iv) After masking the remaining hydroxyl group of the resin in which a part of the hydroxyl group of the polyol obtained by dehydration condensation of the unsaturated bond-containing dicarboxylic acid and the polyol remains, graft polymerization of the ethylenically unsaturated monomer A chain extender having a plurality of functional groups that react with the hydroxyl group Preference is given to tylene diisocyanate or adipoyl dichloride.

  The present invention includes a water-disintegrating block copolymer produced by the above production method.

  According to the present invention, it is possible to provide a water-disintegrating block copolymer which is a new plastic material having an unprecedented rapid decomposition performance in water.

<Method for producing water-disintegrating block copolymer>
The method for producing a water-disintegrating block copolymer of the present invention is characterized by reacting the following (a), (b), and (c).

(A): (a1) and / or (a2) below
(A1): Polyalkylene glycol (a2): Aliphatic polyester having hydroxyl groups at both ends obtained by esterification reaction of polyalkylene glycol and aliphatic dicarboxylic acid or anhydride thereof (b): Including polyoxyalkylene group Aliphatic polyester having hydroxyl groups at both ends (c): Chain extender having a plurality of functional groups that react with hydroxyl groups (a) used in the present invention is any one represented by (a1) and / or (a2) It may be a thing.

  As (a), it is preferable to have a structural unit represented by the following general formula (1).

(In the formula (1), n is an integer of 1 or more, l is 0 or 1, A is a structural unit derived from polyalkylene glycol having a number average molecular weight of 300 to 20,000, and G1 has 1 carbon atom. -18 aliphatic hydrocarbon groups.)
(A) used in the present invention preferably has a structural unit represented by the above formula (1), and among them, n is preferably 1 to 50.

  Examples of the polyalkylene glycol (a1) include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and mixtures thereof. The number average molecular weight of the polyalkylene glycol is 300 to 20,000, preferably 400 to 5,000, more preferably 500 to 2,000. The polyalkylene glycol is not particularly limited, but polyethylene glycol is preferable from the viewpoint of hydrophilicity and degradability.

  The aliphatic polyester having a hydroxyl group at both ends of (a2) can be obtained by esterification reaction of polyalkylene glycol and aliphatic dicarboxylic acid or its anhydride, and the polyalkylene glycol is the same as (a1) above. Is used.

  Examples of the aliphatic dicarboxylic acid include succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, or a mixture thereof. Also, anhydrides of these aliphatic dicarboxylic acids can be used.

The aliphatic dicarboxylic acid or anhydride thereof is not particularly limited, but succinic acid or succinic anhydride is preferable.
(A) used in the present invention is preferably an aliphatic polyester having hydroxyl groups at both ends obtained by an esterification reaction of polyethylene glycol and an aliphatic dicarboxylic acid or an anhydride thereof from the viewpoint of biodegradability.

  A known method can be used for the esterification reaction between polyalkylene glycol and aliphatic dicarboxylic acid or its anhydride. In order to use both ends as hydroxyl groups, the hydroxyl group / carboxyl group ratio (molar ratio). ) Is in the range of 1.05 to 1.50, preferably in the range of 1.10 to 1.30. If it is less than 1.05, the remaining unreacted carboxylic acid group may adversely affect the block copolymerization reaction in the subsequent step, which is not preferable. On the other hand, when the molecular weight is larger than 1.50, the resulting aliphatic polyester has a low molecular weight, which may adversely affect physical properties such as water absorption and strength reduction.

  (B) used in the present invention may be any aliphatic polyester that does not contain a polyoxyalkylene group and has hydroxyl groups at both ends. For example, it is obtained from an aliphatic diol and an aliphatic dicarboxylic acid. Aliphatic polyester, aliphatic polycarbonate, aliphatic poly (hydroxycarboxylic acid), or a mixture thereof.

  (B) preferably has a structural unit represented by the following general formula (2).

  (In the formula (2), m is an integer of 1 or more, k is 0 or 1, E is an aliphatic hydrocarbon group having 1 to 18 carbon atoms, G2 is an oxygen atom or the following general formula (3 ).)

(In Formula (3), G3 is a C1-C18 aliphatic hydrocarbon group.)
(B) used in the present invention preferably has a structural unit represented by the above formula (2), and among them, m is preferably 5 to 150.
When (a) used in the present invention has the structural unit represented by the general formula (1) and (b) has the structural unit represented by the general formula (2) In the general formulas (1) and (2), n + m ≧ 3 is preferable, and 200 ≧ n + m ≧ 6 is more preferable. When n + m satisfies the above relationship, both water absorption and water disintegration can be achieved.

E and G ₃ are each independently an aliphatic hydrocarbon group having 1 to 18 carbon atoms, preferably an aliphatic hydrocarbon group having 2 to 10 carbon atoms.
When (b) is an aliphatic polyester obtained from an aliphatic diol and an aliphatic dicarboxylic acid, examples of the aliphatic diol include ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, or these And the like.

  The aliphatic diol is not particularly limited, but ethylene glycol, tetramethylene glycol, or a mixture thereof is preferable from the viewpoint of water disintegration and water absorption of the final water disintegrable block copolymer.

  Examples of the aliphatic dicarboxylic acid include succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, or a mixture thereof. It is safe to use an aliphatic dicarboxylic acid anhydride. Although not particularly limited, succinic acid and adipic acid are preferable.

A known method can be used for the esterification reaction. However, since both ends are hydroxyl groups as in the case of (a2), the hydroxyl group / carboxyl group ratio (molar ratio) is 1.05 to 1.50. The range is preferably 1.10 to 1.30. If it is less than 1.05, the remaining unreacted carboxylic acid group may adversely affect the block copolymerization reaction in the subsequent step, which is not preferable. On the other hand, when the molecular weight is larger than 1.50, the resulting aliphatic polyester has a low molecular weight, which may adversely affect physical properties such as water absorption and strength reduction.

  When (b) is an aliphatic polycarbonate, for example, polyethylene carbonate, polypropylene carbonate, or a mixture thereof can be used. Although it does not specifically limit, polyethylene carbonate is preferable. A known method can be used as a method for producing an aliphatic polycarbonate. However, in order to improve dispersibility in a later step, the aliphatic polycarbonate has a low molecular weight. Specifically, the number average molecular weight is 50. Or less, preferably 300 to 30,000. In addition, it is also possible to use a high molecular weight polymer having a molecular weight of 100,000 or more, which has been reduced in molecular weight by hydrolysis.

When (b) is an aliphatic poly (hydroxycarboxylic acid), examples of the hydroxycarboxylic acid used as a raw material include lactic acid, glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 4-hydroxyvaleric acid, and 5-hydroxyvaleric acid. Examples include herbal acid, 6-hydroxycaproic acid, and a mixture thereof. When there is an optically active substance, any optically active substance may be used.

Although not particularly limited, (b) is preferably polybutylene adipate, polyethylene butylene adipate, polybutylene succinate, or polyethylene carbonate.
(C) used in the present invention is a chain extender having a plurality of functional groups that react with hydroxyl groups. The functional group that reacts with the hydroxyl group of the chain extender is not particularly limited as long as it is capable of extending the polymer chain by binding to the hydroxyl groups at both ends of (a) and (b). A bond, a carbonate bond, and a urethane bond are preferable.

  Examples of the bond that becomes an ester bond include oxalyl dichloride, succinyl dichloride, adipoyl dichloride, sebacoyl dichloride, dodecandioyl dichloride, etc. having two acid chloride groups in the molecule. Other N, N′-acyl bislactam compounds include N, N′-sacyl biscaprolactam, N, N′-adipylbisbutyrolactam, N, N′-suberyl biscaprolactam, N, N′-sacylbi Examples include spiperidone and N, N′-adipylbispiperidone. Furthermore, examples of the aliphatic dicarboxylic acid diaryl ester include diphenyl succinate, diphenyl glutarate, diphenyl adipate, diphenyl sebacate and the like.

  Examples of the bond that becomes a carbonate bond include diethyl carbonate, dipropyl carbonate, dibutyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate, and the like.

  Examples of the bond that becomes a urethane bond include methylene diisocyanate, ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, octamethylene diisocyanate, and the like. In the case of a urethane reaction, a general urethane reaction catalyst such as dibutyltin dilaurate, dibutyltin diacetate, or bismuth tris (2-ethylhexanoate) can be used as a catalyst as necessary.

Although not particularly limited, (c) is preferably hexamethylene diisocyanate or adipoyl dichloride.
When (a) and (b) are combined with the chain extender (c), the ratio of the functional group amount / total hydroxyl group amount in (c) affects the molecular weight of the block copolymer to be produced. Higher molecular weight is obtained as this ratio is closer to 1.0, and the ratio is preferably in the range of 0.925 to 1.075 from the viewpoint of improving mechanical strength and dispersibility.

As a method for producing the water-disintegrating block copolymer of the present invention, the above (a) and (b) are mixed in such an amount that the weight ratio ((a) :( b)) is 100: 1 to 100: 100. In addition, it is preferable to add 0.5 to 10 parts by weight of (c) and react with respect to 100 parts by weight of the total of (a) and (b). An example will be described below.

  The inside of the reaction vessel having a stirrer, a raw material introduction mechanism, and a temperature control mechanism is replaced with an inert gas. Charge (a) and (b) into a reaction vessel. At this time, the amount of (a) and (b) is such that the weight ratio ((a) :( b)) is preferably 100: 1 to 100: 100, more preferably 100: 3 to 100: 50. And

  After (a) and (b) are melted, the chain extender (c) is introduced into the reaction vessel while stirring in the vessel. The introduction amount is preferably 0.1 to 10 parts by weight of (c) with respect to 100 parts by weight of the total of (a) and (b). The introduction method is not particularly limited, and may be introduced continuously or intermittently. The reaction may be carried out in a molten state, but preferably, an organic solvent and a dispersing agent are charged thereafter, and (a), (b) and (c) are reacted in an organic solvent containing the dispersing agent.

As the organic solvent used in the production method of the present invention, an organic solvent having a low solubility of the resulting water-disintegrable block copolymer is preferable. For example, the organic solvent is composed of an aliphatic hydrocarbon, an ester solvent, a ketone solvent, and an aromatic solvent. Preferably, the solvent is at least one solvent selected from the group.

  Specifically, aliphatic hydrocarbons include aliphatic hydrocarbons having 3 to 20 carbon atoms such as hexane, heptane, octane, pentane, and cyclohexane, and ester solvents include methyl acetate and ethyl acetate. , Various esters having 3 to 20 carbon atoms such as n-butyl acetate, isobutyl acetate, amyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-butyl ether acetate, ethyl Examples include esters having various alkoxy groups having 3 to 20 carbon atoms such as ethoxypropionate, and examples of ketone solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl isobutyl ketone, methyl amyl ketone, cyclohexa Include the number of carbon atoms, such as emissions is a ketone solvent, from 3 to 20, the aromatic solvent, toluene, xylene, aromatic solvent carbon atoms, such as are 6-20 ethylbenzene. Of these, aliphatic hydrocarbons such as hexane, heptane, and isooctane are preferable for improving polymer dispersibility.

The dispersant used in the present invention has an effect of dissolving in the organic solvent described above and stably dispersing the resulting water-disintegratable block copolymer.
The dispersant is preferably a resin having a branched polyolefin unit and an aliphatic polyester unit.

The dispersant used in the present invention is preferably at least one resin selected from the group consisting of the following (i) to (iv).

(I) Resin in which hydroxyl group of polyol obtained by dehydration condensation of alkenyl succinic anhydride and polyol is masked (ii) Dehydration condensation of fatty acid on part of residual hydroxyl group of polyester obtained by dehydration condensation of dicarboxylic acid and pentaerythritol (Iii) After graft-polymerizing an ethylenically unsaturated monomer to a resin in which a part of the hydroxyl group of the polyol obtained by dehydration condensation of an unsaturated bond-containing dicarboxylic acid and the polyol remains, the remaining hydroxyl group Masked resin (iv) After masking the remaining hydroxyl group of the resin in which a part of the hydroxyl group of the polyol obtained by dehydration condensation of the unsaturated bond-containing dicarboxylic acid and the polyol remains, graft polymerization of the ethylenically unsaturated monomer The above-mentioned alkenyl succinic anhydride is, for example, α-olefin converted to anhydrous So-called ene added indirectly substituted onto ynoic acid - are known compounds obtained by the synthesis.

  The polyol is a compound having at least two hydroxyl groups in the molecule, and polyalkylene ether glycol, polyester obtained by polymerizing diol and dicarboxylic acid, and a mixture thereof are used.

Examples of the dicarboxylic acid used in the alkyd resin include aromatic dibasic acids such as isophthalic acid and terephthalic acid, and aliphatic dibasic acids such as adipic acid and sebacic acid.
Examples of the unsaturated bond-containing dicarboxylic acid include maleic acid and itaconic acid, and anhydrides thereof can also be used.

  The reagent for masking the hydroxyl group is not particularly limited as long as it has one functional group that reacts with the hydroxyl group in the molecule and the other terminal group has a functional group that is inactive in the non-aqueous dispersion polymerization reaction system. Are, for example, monoisocyanate compounds such as ethyl isocyanate, butyl isocyanate, and hexyl isocyanate.

  In the method for producing a water-disintegrating block copolymer of the present invention, a catalyst can be used as necessary. When adding the catalyst, it is added while controlling the reaction temperature. It is not always necessary to add the solvent after the addition of the solvent. It is also possible to start the reaction by adding a catalyst after adding the chain extender (c) to (a) and (b). Alternatively, it is also possible to add a catalyst to the chain extender (c) in advance, and add these to (a) and (b) for reaction.

  The catalyst used for the reaction is not particularly limited, and known catalysts generally used for the reaction of isocyanates and polyols such as organometallic compounds, metal salts, tertiary amines, other base catalysts and acid catalysts are used. be able to. Examples include dibutyltin dilaurate (hereinafter abbreviated as DBTDL), dibutyltin diacetate, dibutyltin di (dodecylthiolate), dibutyltin di (dodecylthiolate), dimethyltin dilaurate, stannous octanoate, 1,1,3 , 3, -tetrabutyl-1,3-dilauryloxycarbonyl-distanoxane, bismuth tris (2-ethylhexanoate), phenylmercuric acetate, zinc octoate, lead octoate, zinc naphthenate, lead naphthenate, triethylamine (TEA), tetra Methylbutanediamine (TMBDA), N-ethylmorpholine (NEM), 1,4-diaza [2.2.2] bicyclooctane (DABCO), 1,8-diazabicyclo [5.4.0] -7-undecene ( DBU), N, N'-dimethyl There is such as 1,4-diazacyclohexane (DMP). Of these, a catalyst containing tin and bismuth is more preferable because of its high activity.

  The amount of the catalyst used in the reaction varies depending on the reaction temperature and the type of the catalyst and is not particularly limited, but is 0.0001 to 0.1 mol, more preferably 0, per mol of the total of (a) and (b). About 0.001 to 0.1 mol is sufficient.

  Further, the reaction is carried out under the condition in which substances other than the above-mentioned (a), (b) and chain extender (c), for example, ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, etc. coexist. Also good.

The reaction temperature varies depending on the type and amount of the catalyst used, but 50 to 180 ° C. is appropriate. More preferably, it is 60-150 degreeC, More preferably, it is the range of 80-120 degreeC. If the reaction temperature is less than 50 ° C., the reaction rate is slow and not economical. Moreover, when it exceeds 180 degreeC, a product may thermally decompose.

The reaction time varies depending on the type and amount of the catalyst used, the reaction temperature, and the like, and is not particularly limited, but about 1 minute to 10 hours is sufficient.
The reaction pressure is not particularly limited. The reaction can be carried out at normal pressure, reduced pressure or increased pressure. More preferably, the reaction is performed under normal pressure or weak pressure.

  It is preferable that the stirring device is provided with stirring conditions necessary for dispersion. As a stirring blade for that purpose, a general stirring blade (such as a turbine, paddle, inclined paddle, fouler blade, or squid blade) may be used, or a disper, a homomixer, or the like may be used.

The water-disintegrating block copolymer obtained by the above production method has the above-mentioned unit derived from (a), the unit derived from (b), and the unit derived from (c).
Although the preferable quantity ratio of the unit derived from (a), the unit derived from (b), and the unit derived from (c) is influenced by the number average molecular weight and composition ratio of each unit, the unit derived from (a) The unit derived from (c) is preferably 0.5 to 10 parts by weight based on 100 parts by weight in total with the unit derived from (b). If the amount of the unit derived from (c) is too large, the water-disintegrating property of the water-disintegrating block copolymer tends to be reduced.

  The water-disintegrable block copolymer produced by the production method of the present invention has a weight average molecular weight of usually 10,000 to 10,000,000, preferably 30,000 to 1,000,000. It is a range. Within this range, the strength and elongation of the resin are good and the molding processability is excellent.

  In the present invention, the weight average molecular weight, number average molecular weight, and molecular weight distribution (weight average molecular weight / number average molecular weight) are all values in terms of polyethylene oxide determined by gel permeation chromatography (GPC).

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.
[Example]
The weight average molecular weight, number average molecular weight, and molecular weight distribution (weight average molecular weight / number average molecular weight) in this example were measured using Shimadzu LC-10A, column: SHODEX KD-806M.
30 cm × 2 pieces, detection: RI detector, solvent: DMF.

[Production Example 1] Synthesis of Aliphatic Polyester (R-1) Containing Polyoxyethylene Part and Both Ends are Hydroxyl Anhydrous to a 3000 ml stirring rod round bottom flask equipped with a Dean-Stark apparatus (water separator) 90.4 g (0.90 mol) of succinic acid, 990.1 g (0.99 mol) of polyethylene glycol 1000 having a molecular weight of 1000, and 1.63 g of tetraisopropyl orthotitanate are added as a catalyst. To this, 800 ml of diethylbenzene as an azeotropic solvent was added and refluxed for 8 hours. Next, the solvent was distilled off under reduced pressure, and the mixture was stirred at 200 ° C. for 5 hours under a reduced pressure of 5 mmHg to conduct a polyesterification reaction. Polyester (R-1) obtained after cooling had a terminal hydroxyl value of 4.79 KOH mg / g, an acid value of 0.63 KOH mg / g, and a number average molecular weight calculated from the terminal hydroxyl value of 23,400.

[Production Example 2] Synthesis of Aliphatic Polyester (R-2) Containing Polyoxyethylene Part and Both Ends are Hydroxyl Groups In a 2000 ml round bottom flask with a stir bar equipped with a Dean-Stark apparatus (water separator) 70.2 g (0.59 mol) of acid, 1486.0 g (0.74 mol) of polyethylene glycol 2000 having a molecular weight of 2000, and 0.38 g of tetraisopropyl orthotitanate as a catalyst were stirred at 180 ° C. for 46 hours for polyesterification reaction Went. Polyester (R-2) obtained after cooling had a terminal hydroxyl value of 23.5 KOH mg / g, an acid value of 0.61 KOH mg / g, and a number average molecular weight calculated from the terminal hydroxyl value of 4,780.

[Production Example 3] Synthesis of polybutylene succinate (PBS) having hydroxyl groups at both ends 488.5 g (4.14 mol) of succinic acid in a 2000 ml round bottom flask equipped with a Dean-Stark apparatus (water separator) ), 410.3 g (4.55 mol) of 1,4-butanediol and 0.06 g of tetraisopropyl orthotitanate as a catalyst, stirred at 180 ° C. for 6 hours, and further under reduced pressure of 31 mmHg at 180 ° C. for 8 hours. The mixture was stirred to conduct a polyesterification reaction. The PBS diol obtained after cooling had a terminal hydroxyl value of 39.4 KOHmg / g, an acid value of 0.39 KOHmg / g, and a number average molecular weight calculated from the terminal hydroxyl value of 2,850.

[Production Example 4] Synthesis of polyethylene carbonate (PEC-1) having hydroxyl groups at both ends (1) Catalyst preparation 10.4 g of commercially available zinc oxide, 16.3 g of glutaric acid, 0.25 g of zinc sulfide and 23.1 g of dioxane. , Charged in a stainless steel ball mill inner cylinder with an internal volume of 500 ml containing 30 stainless steel balls with a diameter of 15.8 mm and 30 stainless steel balls with a diameter of 19 mm, and contacted with a planetary ball mill for 9 hours at an acceleration of 3.5 G It was. The obtained contact-treated product was dried under reduced pressure at 150 ° C. for 3 hours to obtain a zinc-containing catalyst.

(2) Polymerization In an autoclave having an internal volume of 3000 cc, 893.90 g of 1,3-dioxolane containing 89 ppm of water, 2.40 g of the above zinc-containing catalyst and ethylene oxide 219
. 00 g was charged and carbon dioxide was added at room temperature to a pressure of 1.5 MPa. Then, it heated up to 80 degreeC and superposed | polymerized for 2 hours. Immediately after the temperature increase, the pressure increased to 2.7 MPa, but carbon dioxide gas was consumed with the reaction, and the pressure decreased. After completion of the polymerization, the autoclave was cooled and then depressurized to take out the polymerization solution. The polymerization solution was in a state where the polymer was completely dissolved. The polymer solution taken out was filtered through a filter having a pore diameter of 1 micron to remove the solid zinc-containing catalyst, and the filtrate was dried to obtain a polymer. The polymer yield was 217.70 g. Moreover, the number average molecular weight by GPC measurement of the obtained polyethylene carbonate (PEC-0) was 48,000.

(3) Reduction in molecular weight by hydrolysis In a 2000 ml round bottom flask with a stir bar, 78.56 g of the above-mentioned polyethylene carbonate (PEC-0), 1.75 g of an aqueous sodium carbonate solution as a catalyst, 175 ml of water and 700 ml of 1,3-dioxolane were added. And stirred at 70 ° C. for 7 hours. After standing to cool, a catalyst neutralizing amount of sulfuric acid was added, and 1,3-dioxolane was distilled off under reduced pressure. The resulting reaction product was placed in a separatory funnel and extracted twice with 400 ml of methylene chloride. The obtained oil layer was washed 6 times with 200 ml of water and then dried over magnesium sulfate, and methylene chloride was distilled off under reduced pressure using a rotary evaporator. The obtained polyethylene carbonate (PEC-1) was 27.50 g, and the number average molecular weight was reduced to 5200. ^The amount of carbon adjacent to the hydroxyl group and the amount of carbon in the main chain were determined by ¹³ C-NMR, and the amount of terminal hydroxyl group was calculated. As a result, it was 0.36 mmol / g.

[Production Example 5] Synthesis of polyethylene carbonate (PEC-2) having hydroxyl groups at both ends In a 2000 ml round bottom flask with a stir bar, 100.99 g of the above polyethylene carbonate (PEC-0) and 1.70 g of an aqueous sodium carbonate solution as a catalyst , 180 ml of water and 820 ml of 1,3-dioxolane were added and stirred at 60 ° C. for 6 hours. After standing to cool, a catalyst neutralizing amount of sulfuric acid was added, and 1,3-dioxolane was distilled off under reduced pressure. The resulting reaction product was placed in a separatory funnel and extracted twice with 400 ml of methylene chloride. The obtained oil layer was washed 6 times with 200 ml of water and then dried over magnesium sulfate, and methylene chloride was distilled off under reduced pressure using a rotary evaporator. The obtained polyethylene carbonate (PEC-2) was 77.86 g, and the number average molecular weight was reduced to 10,800. ^The amount of carbon adjacent to the hydroxyl group and the amount of carbon in the main chain were determined by ¹³ C-NMR, and the amount of terminal hydroxyl group was calculated. As a result, it was 0.20 mmol / g.

[Production Example 6] Synthesis of Dispersant (1) 20 g of hexamethylene adipate having an average molecular weight of 1000 and 0.98 g of maleic anhydride were placed in a 100 ml three-necked flask equipped with a stirring blade, and the mixture was heated at 150 ° C under a nitrogen stream at Stir for hours. Furthermore, under a reduced pressure of 20 mmHg, the temperature was gradually raised to 170 ° C. and the mixture was stirred and then allowed to cool to obtain an unsaturated bond-containing polyol having an average molecular weight of 2000. 5 g of this unsaturated bond-containing polyol was placed in a 100 ml eggplant type flask, 10 g of butyl acetate was added, and then 10 g of lauryl methacrylate and 0.4 g of benzoyl peroxide were added dropwise from a dropping funnel in 30 minutes at 110 ° C. under a nitrogen stream. After maintaining at 110 ° C. for 2 hours, the reaction was further continued at 130 ° C. for 2 hours. Next, after adding 2 g of ethyl isocyanate and reacting at 80 ° C. for 6 hours, the unreacted material was distilled off at 5 mmHg to obtain a dispersant (1).

[Production Example 7] Synthesis of dispersant (2) 20.0 g of polybutenyl succinic acid (PIBSA-2: acid value 38.0 mgKOH / g, polystyrene equivalent weight average molecular weight 3500) manufactured by Toho Chemical Co., Ltd., polyethylene 10.0 g of glycol # 1000 (manufactured by Kanto Chemical Co., Ltd.) and 0.02 g of tetraisopropyl orthotitanate were placed in a 100 ml round bottom flask equipped with a stirring blade and reacted at 180 ° C. for 20 hours in a nitrogen stream. The reaction was further carried out at 180 ° C. for 20 hours under a reduced pressure of 5 mmHg. Next, after adding 4 g of ethyl isocyanate and reacting at 80 ° C. for 6 hours, the unreacted material was distilled off at 5 mmHg to obtain a dispersant (2) which was a brown rubber-like material.

  In a 500 ml four-necked separable flask equipped with a stirrer, thermometer, and condenser, 90.3 g of polyester (R-1) (synthesized in Production Example 1), polybutylene adipate (PBA) diol (Mitsui Chemical Polyurethane Co., Ltd.) ); Average molecular weight 2,000) 10.1 g (weight ratio: 9/1) was charged, and the inside of the reactor was kept in a nitrogen atmosphere. The temperature was raised to 70 ° C. in an oil bath to dissolve each diol. After dissolution, the temperature was raised to 90 ° C., and then 0.92 g of dispersant (1) (synthesized according to Production Example 6) and 100 g of isooctane were added to the reactor. After pumping in with nitrogen, the stirring rotation speed was increased to 1000 rpm. After stirring for 1 hour, 2.63 g of hexamethylene diisocyanate (HDI) (NCO / OH molar ratio = 0.980) was charged with a syringe, then 0.06 g of dibutyltin dilaurate (DBTDL) catalyst was added, and 6 By reacting for a period of time, a particulate block copolymer (1) dispersed in a solvent was obtained. The weight average molecular weight was 78,200, and the molecular weight distribution was 1.83.

  Except polyester (R-1) 85.7g, PBA diol 15.4g (weight ratio: 8.5 / 1.5), HDI 2.92g (NCO / OH molar ratio = 0.988) The same operation as in Example 1 was performed to obtain a particulate block copolymer (2). The weight average molecular weight was 86,200, and the molecular weight distribution was 1.96.

Example 1 except that 80.6 g of polyester (R-1), 20.1 g of PBA diol (weight ratio: 8/2), and 3.15 g of HDI (NCO / OH molar ratio = 0.924) were used. The same operation was performed to obtain a particulate block copolymer (3). The weight average molecular weight is 49,90
The molecular weight distribution was 0, and the molecular weight distribution was 1.82.

  85.1 g of polyester (R-1), 15.2 g of PBA diol (weight ratio: 8.5 / 1.5), 4.22 g of HDI (NCO / OH molar ratio = 0.994), and organic solvent Except for using heptane, the same operation as in Example 1 was performed to obtain a particulate block copolymer (4). The weight average molecular weight was 93,300, and the molecular weight distribution was 2.00.

  90.3 g of polyester (R-2) (synthesized according to Production Example 2) instead of polyester (R-1), and 10.2 g of PBS diol (synthesized according to Production Example 3) instead of PBA diol (weight ratio: 9 / 1) The same procedure as in Example 1 was carried out except that 3.43 g (NCO / OH molar ratio = 0.951) of HDI and normal octane were used as the organic solvent to obtain a particulate block copolymer (5). Obtained. The weight average molecular weight was 160,000 and the molecular weight distribution was 1.89.

  90.4 g of polyester (R-2) instead of polyester (R-1), 10.5 g of polyethylene butylene adipate (PEBA) diol (Mitsui Chemical Polyurethane Co., Ltd .; average molecular weight 2,000) instead of PBA diol (Weight ratio: 9/1), HDI was 3.85 g (NCO / OH molar ratio = 0.951), and the organic solvent was changed to heptane. Combined (6) was obtained. The weight average molecular weight was 204,000, and the molecular weight distribution was 2.01.

  85.2 g of polyester (R-2) instead of the above polyester (R-1), 14.6 g of PEBA diol instead of PBA diol (weight ratio: 8.5 / 1.5), 4.00 g of HDI ( NCO / OH molar ratio = 0.951), except that heptane was used as the organic solvent, the same operation as in Example 1 was carried out to obtain a particulate block copolymer (7). The weight average molecular weight was 197,000, and the molecular weight distribution was 2.01.

  Polyester (R-1) (synthesized according to Production Example 1) 27.30 g, PBA diol (Mitsui Chemical Polyurethane Co., Ltd .; average molecular weight 2000) 3.30 g (weight ratio 9/1) ), 30 mL of toluene was added as a solvent and mixed at 90 ° C. As chain extenders, 0.63 g of hexamethylene diisocyanate (HDI) (NCO / OH molar ratio = 0.963) and 50 mg of dibutyltin dilaurate were respectively charged with a syringe and stirred at 90 ° C. for 4 hours. After adding 0.30 g of 2,6-di-tert-butyl-4-methylphenol as an antioxidant and mixing, toluene was distilled off under reduced pressure to obtain a block copolymer (8). The obtained block copolymer had a weight average molecular weight of 126,000 and a molecular weight distribution of 2.42.

  Except for polyester (R-1) 24.37 g, PBA diol 4.30 g (weight ratio: 8.5 / 1.5), HDI 0.67 g (NCO / OH molar ratio = 0.957) The same operation as in Example 8 was performed to obtain a block copolymer (9). The weight average molecular weight was 128,000, and the molecular weight distribution was 2.37.

24.00 g of polyester (R-1) and 6.00 g of PBA diol (weight ratio: 8 /
2) The same operation as in Example 8 was carried out except that HDI was changed to 0.80 g (NCO / OH molar ratio = 0.958) to obtain a block copolymer (10). The weight average molecular weight was 112,000 and the molecular weight distribution was 1.75.

  80.7 g of polyethylene glycol 20000 (manufactured by Merck; average molecular weight 20,000) is used instead of polyester (R-1), and 20 of polyethylene carbonate (PEC-1) diol (synthesized according to Production Example 4) is used instead of PBA diol. 0.2 g (weight ratio: 8/2) and the same procedure as in Example 1 except that HDI was changed to 0.888 g (NCO / OH molar ratio = 0.955), and a particulate block copolymer (11 ) The weight average molecular weight was 146,000, and the molecular weight distribution was 3.38.

  80.4 g of polyester (R-1), 20.0 g of polyethylene carbonate (PEC-1) diol instead of PBA diol (weight ratio: 8/2), 1.39 g of adipoyl dichloride instead of HDI (acid chloride) / OH molar ratio = 0.978), and the same operation as in Example 1 was carried out except that no catalyst was added to obtain a particulate block copolymer (12). The weight average molecular weight was 62,500, and the molecular weight distribution was 1.85.

  65.8 g of polyester (R-1), 28.5 g of polyethylene carbonate (PEC-2) diol (synthesized according to Production Example 5) instead of PBA diol (weight ratio: 7/3), 1.58 g of HDI (NCO / OH molar ratio = 0.987), and the same procedure as in Example 1 was performed except that 1.02 g of the dispersant (2) (synthesized according to Production Example 7) was used instead of the dispersant (1). A block copolymer (13) was obtained. The weight average molecular weight was 56,800, and the molecular weight distribution was 1.79.

[Comparative Example 1]
The same procedure as in Example 1 was carried out except that 100.9 g of polyester (R-1), 1.27 g of HDI (NCO / OH molar ratio = 0.958), and no PBA diol were used. A polymer (ratio 1) was obtained. The weight average molecular weight was 92,900, and the molecular weight distribution was 1.99.

[Comparative Example 2]
The same procedure as in Example 8 was carried out except that 31.1 g of polyester (R-1), 0.442 g of HDI (NCO / OH molar ratio = 0.993), and no PBA diol were used. A ratio 2) was obtained. The weight average molecular weight was 112,000 and the molecular weight distribution was 1.97.

[Preparation of water absorption and water disintegration test piece]
A 300 μm thick sheet obtained by hot pressing each of the block copolymers synthesized by the above production method at 80 ° C. was cut into a square having a side of 5 cm.

[Measurement of water absorption]
Place the test piece obtained above in a 500 ml beaker filled with water, take out the test piece at regular intervals, wipe off the water adhering to the surface, measure the weight, and absorb into the block copolymer. The amount of water produced was measured. The measurement was performed until the test piece collapsed, and the weight of water finally absorbed was defined as the absorption rate (% by weight) with respect to the weight of the first test piece. The results are shown in Table 1.

The block copolymer of the present invention has a certain amount of water absorption, and the water absorption of the block copolymer can be controlled by changing the composition of the block copolymer.
[Measurement of water disintegration]
A 300 ml beaker was charged with 300 ml of water and stirred at 200 rpm. The test piece was put in and the time until the test piece collapsed visually was measured for a maximum of 7 days. The results are shown in Table 2.

  The block copolymer of the present invention has the ability to disintegrate in a large amount of water, and the water disintegration property can be controlled over a wide range by changing the composition of the block copolymer.

  Since the block copolymer of the present invention has practically sufficient water disintegration and absorption properties, for example, water disintegratable articles, water disintegrating toilet cleaning articles, and water disintegrating packaging materials are available. Can be used.

  Further, the block copolymer of the present invention has applicability as an alternative material for all molded products that are expected to be left in water or discarded.

Claims (12)

A method for producing a water-disintegrating block copolymer, comprising reacting the following (a), (b), and (c):
(A): (a1) and / or (a2) below
(A1): Polyalkylene glycol (a2): Aliphatic polyester having hydroxyl groups at both ends obtained by esterification reaction of polyalkylene glycol and aliphatic dicarboxylic acid or anhydride thereof (b): Including polyoxyalkylene group Aliphatic polyester having hydroxyl groups at both ends (c): chain extender having a plurality of functional groups that react with hydroxyl groups (A) has a structural unit represented by the following general formula (1), and (b) has a structural unit represented by the following general formula (2) (however, the following general formulas (1) and (2) 2) n + m ≧ 3). The method for producing a water-disintegrating block copolymer according to claim 1, wherein:

(In the formula (1), n is an integer of 1 or more, l is 0 or 1, A is a structural unit derived from polyalkylene glycol having a number average molecular weight of 300 to 20,000, and G1 has 1 carbon atom. -18 aliphatic hydrocarbon groups.)

(In the formula (2), m is an integer of 1 or more, k is 0 or 1, E is an aliphatic hydrocarbon group having 1 to 18 carbon atoms, G2 is an oxygen atom or the following general formula (3 ).)

(In Formula (3), G3 is a C1-C18 aliphatic hydrocarbon group.) (A) is an aliphatic polyester having a hydroxyl group at both ends obtained by an esterification reaction of polyethylene glycol and an aliphatic dicarboxylic acid or an anhydride thereof;
The method for producing a water-disintegrable block copolymer according to claim 1 or 2, wherein (b) is polybutylene adipate having hydroxyl groups at both ends, or polyethylene butylene adipate having hydroxyl groups at both ends. (A) is an aliphatic polyester having a hydroxyl group at both ends obtained by an esterification reaction of polyethylene glycol and an aliphatic dicarboxylic acid or an anhydride thereof;
The method for producing a water-disintegrable block copolymer according to claim 1 or 2, wherein (b) is a polybutylene succinate having hydroxyl groups at both ends.   The water-disintegrating block co-polymer according to any one of claims 1 to 4, wherein (a), (b), and (c) are reacted in an organic solvent containing a dispersant. Manufacturing method of coalescence. (A) is an aliphatic polyester having a hydroxyl group at both ends obtained by an esterification reaction of polyethylene glycol and an aliphatic dicarboxylic acid or an anhydride thereof;
(B) is a polyethylene carbonate having hydroxyl groups at both ends;
The method for producing a water-disintegrating block copolymer according to claim 1 or 2, wherein (a), (b), and (c) are reacted in an organic solvent containing a dispersant.   (A) and (b) are mixed in such an amount that the weight ratio ((a) :( b)) is 100: 1 to 100: 100, and a total of 100 parts by weight of (a) and (b) (C) 0.5-10 weight part is added and made to react, The manufacturing method of the water-disintegrating block copolymer of any one of Claims 1-6 characterized by the above-mentioned.   The method for producing a water-disintegrable block copolymer according to any one of claims 1 to 7, wherein the aliphatic dicarboxylic acid is succinic acid.   The method for producing a water-disintegrating block copolymer according to any one of claims 5 to 8, wherein the dispersant is a resin having a branched polyolefin unit and an aliphatic polyester unit. The method for producing a water-disintegrating block copolymer according to claim 9, wherein the dispersant is at least one resin selected from the group consisting of the following (i) to (iv).
(I) Resin in which hydroxyl group of polyol obtained by dehydration condensation of alkenyl succinic anhydride and polyol is masked (ii) Dehydration condensation of fatty acid on part of residual hydroxyl group of polyester obtained by dehydration condensation of dicarboxylic acid and pentaerythritol (Iii) After graft-polymerizing an ethylenically unsaturated monomer to a resin in which a part of the hydroxyl group of the polyol obtained by dehydration condensation of an unsaturated bond-containing dicarboxylic acid and the polyol remains, the remaining hydroxyl group Masked resin (iv) After masking the remaining hydroxyl group of the resin in which a part of the hydroxyl group of the polyol obtained by dehydration condensation of the unsaturated bond-containing dicarboxylic acid and the polyol remains, graft polymerization of the ethylenically unsaturated monomer Resin made   The production of a water-disintegrating block copolymer according to any one of claims 1 to 10, wherein the chain extender having a plurality of functional groups that react with a hydroxyl group is hexamethylene diisocyanate or adipoyl dichloride. Method.   The water-disintegrating block copolymer manufactured by the method of any one of Claims 1-11.