JPH09272732A - Production of copolymer of polyoxyalkylene with aliphatic polyester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a copolymer of polyoxyalkylene with an aliphatic polyester useful as a biodegradable hydrogel by reacting a specified aliphatic polyester copolymer with a compound in a molten state under specified conditions. SOLUTION: An aliphatic polyester copolymer (A) comprising 20-90wt.% aliphatic polyester consisting mainly of a 4-10C aliphatic dicarboxylic acid component and a 2-6C aliphatic diol component and 80-10wt.% polyoxyalkylene component having a number-average molecular weight of 300 or above and having a reduced viscosity of 1.0 to below 1.8 as measured under specified conditions is mixed with at least one compound (B) selected among compounds represented by formula I (R is a 2-8C divalent aliphatic residue; and Ar is a 6-12C aryl), formula II (R' is R; and n is 3-11) and formula III (Ar' is Ar) and used in an amount satisfying formula IV [X is the content (mol/10<6> g) of the terminal OH groups of A before being mixed with component B; Y is the amount (wt.%/polymer) of B added; and W is the molecular weight of B], and the resulting mixture is reacted in a molten state in the presence of a polycondensation catalyst in a vacuum or in an atmosphere of an inert gas to obtain a product having a reduced viscosity of 1.8 or above.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyoxyalkylene copolymerized aliphatic polyester, more specifically, a polyoxyalkylene having a high degree of polymerization in which a hydrophobic component is mainly an aliphatic polyester and a hydrophilic component is mainly a polyoxyalkylene component. The present invention relates to a novel method for efficiently producing a copolymerized aliphatic polyester.

[0002]

BACKGROUND OF THE INVENTION Thermoplastic polymers generally have excellent moldability,
It has mechanical properties and is used in large quantities for various purposes as fibers, films, plastics, etc. However,
In recent years, plastics waste has been regarded as a problem as one of the environmental problems on a global scale, and there is a demand for the development of a polymer material that decomposes in a natural environment. Among them, plastics which are decomposed by microorganisms are particularly expected to be functional materials having excellent environmental compatibility.

Aliphatic polyesters have been known to have biodegradability, and typical examples thereof include poly-3-hydroxybutyric acid ester, poly ε-caprolactone, polylactic acid and polyglycolic acid. be able to.

By the way, crosslinked hydrogel materials are now widely used in the field of biochemical applications such as contact lenses, implants, microspheres and drug delivery systems. However, the lack of processability due to its crosslinkability is mentioned as a drawback, and in recent years, hydrogels having no crosslink structure have been developed.

As mentioned above, aliphatic polyesters are known to have biodegradability. On the other hand, PEG is known to be rapidly eliminated from the inside of the living body, and is considered to be safe for the living body. Therefore, it is expected that the PEG-copolymerized aliphatic polyester in which the aliphatic polyester is a hydrophobic component and the PEG is a hydrophilic component can be applied as a hydrogel having biodegradability.

The dyeability, hydrophilicity, adhesiveness of polyester,
A method of copolymerizing polyester with a polyether such as polyethylene glycol (PEG) for the purpose of improving physical properties has been conventionally known. However, the PEG component is generally low in polymerizability, and since it is difficult to increase the degree of polymerization of an aliphatic polyester even with its own homopolymer by an ordinary polymerization method, an aliphatic polyester having a high degree of polymerization of many PEG copolymerization components is difficult. Obtaining a / PEG copolymer and its rapid production are extremely difficult tasks.

At present, a method by ring-opening polymerization of a cyclic ester and a cyclic ether, or ring-opening copolymerization of a cyclic acid anhydride and an excess of cyclic ether has been proposed, but the cyclic compound is once produced and purified. Therefore, there is a problem in productivity.

Further, in the synthesis by the condensation method, the method disclosed in JP-A-7-1 is used.
In Japanese Patent No. 65896, a polycarboxylic acid (PLA) having a high degree of polymerization is prepared by adding a dicarboxylic acid component as a third component to a polymerization reaction system so as to match the molar balance of a carboxyl group and a hydroxyl group.
A method for obtaining a PEG copolymer has been reported. However, in such a method, it is specified that it is difficult to obtain a polymer having a high degree of polymerization as the amount of PEG copolymerized increases. A polymer having a small PEG copolymerization amount with respect to this polylactic acid (PLA) has a low swelling degree and does not sufficiently exhibit the performance as a hydrogel.

Further, polyethylene succinate / PE
A method of chain extension of a G copolymer with adipoyl chloride has been proposed (J. Macromol. Sci., A2.
3,411-422. ), But such a method does not have satisfactory productivity because the chain extension reaction is carried out in a solution.

In JP-A-7-304839, a polyvalent isocyanate is used when 100 parts of an aliphatic polyester consisting of succinic acid and 1,4-butanediol is reacted with 1 to 30 parts of PEG having a molecular weight of 300 or more. The method of addition is described. However, since the obtained PEG-copolymerized polyester has a urethane bond, weather resistance and heat stability are insufficient, and biodegradability tends to be impaired.

[0011]

It is an object of the present invention to provide polyoxyalkylene copolymerized aliphatic polyesters useful as biodegradable hydrogels.

[0012]

Means for Solving the Problems As a result of intensive investigations by the present inventors in order to obtain a copolymerized aliphatic polyester having a high degree of polymerization and having a large amount of polyoxyalkylene component, the present inventors have found that it has an ester-forming functional group at the terminal. A polyoxyalkylene compound having a number average molecular weight of 300 or more is copolymerized at 80 to 10% by weight to an aliphatic polyester copolymer having a specific viscosity, a specific compound is added at a specific ratio, and the mixture is melt-reacted to obtain a target polymer. The present invention has been achieved by finding that the product can be quickly obtained.

That is, according to the present invention, 20 to 90% by weight of an aliphatic polyester (A) mainly composed of an aliphatic dicarboxylic acid component having 4 to 10 carbon atoms and an aliphatic diol component having 2 to 6 carbon atoms, and Reduced viscosity (phenol / 1,1,2,2-) composed of 80 to 10% by weight of polyoxyalkylene component (B) having a number average molecular weight of 300 or more.
Tetrachloroethane mixed solvent (weight ratio 6/4), concentration 1.2 g / dl, measured at temperature 35 ° C.) 1.0 or more and 1.8
In the aliphatic polyester copolymer (C) which is less than the following formula, at least one compound (D) selected from the group consisting of compounds represented by the following formulas (1), (2) and (3) is represented by the following formula (4 ) Is added, and the polycondensation catalyst is added, and the polycondensation reaction is performed in the presence of a polycondensation catalyst under reduced pressure or in an inert gas atmosphere to produce a polyoxyalkylene copolymerized aliphatic polyester having a reduced viscosity of 1.8 or more. Is the way.

[0014]

Embedded image Ar-OOC-R-COO-Ar (1) (In the formula (1), R is a divalent aliphatic residue having 2 to 8 carbon atoms, and Ar is 6 to 6 carbon atoms. 12 represents the aryl group.)

[0015]

Embedded image

(In the formula (2), R'is a divalent aliphatic residue having 2 to 8 carbon atoms, and n is an integer of 3 to 11.)

[0017]

[Chemical 6]

(In the formula (3), Ar 'has 6 to 12 carbon atoms.
Represents an aryl group. )

[0019]

[Number 2] in ^{0.1WX ≦ 10 4 Y ≦ 2.0WX (} 4) ( formula (4), X is OH end groups of the compound (D) before addition of the aliphatic polyester copolymer (C) (mol / 10
⁶ g), Y represents the amount of the compound (D) added (% by weight / polymer), and W represents the molecular weight of the compound (D). )

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below.

The aliphatic polyester copolymer (C) in the present invention is composed of 20 to 90% by weight of the aliphatic polyester (A) and 80 to 10% by weight of the polyoxyalkylene component (B).

The aliphatic polyester (A) is mainly composed of an aliphatic dicarboxylic acid component having 4 to 10 carbon atoms and an aliphatic diol component having 2 to 6 carbon atoms. Examples of the aliphatic dicarboxylic acid component having 4 to 10 carbon atoms include succinic acid, glutaric acid, adipic acid, sebacic acid and the like. These aliphatic dicarboxylic acids may be used for polymerization as they are, or their acid anhydrides,
It may be used as an ester-forming derivative such as a lower alkyl ester.

As the aliphatic diol component having 2 to 6 carbon atoms, ethylene glycol, trimethylene glycol,
Propylene glycol, tetramethylene glycol, diethylene glycol, neopentylene glycol and the like can be mentioned.

Aliphatic polyester (A) in the present invention
Is mainly composed of the above components, but may partially contain a component other than the above. Examples of the component include glycolic acid, lactic acid, ε-oxycaproic acid, hydroxyethoxyacetic acid, β-hydroxybutyric acid, β-hydroxyvaleric acid and the like. These can be used preferably in a proportion of about 30 mol% or less based on all repeating units.

Examples of the polyoxyalkylene component (B) include the following formulas (5) and / or (6)

[0026]

HO (C _m H _2m O) _p H (5) (In the formula (5), m is an integer of 1 to 4, and p is appropriate when the number average molecular weight is 300 or more. It shows a value.)

[0027]

Embedded image R ¹ OOC (CH ₂ ) ₁ O (C _m H _2m O) _p (CH ₂ ) ₁ COOR ² ... (6) (In the formula (6), R ¹ and R ² are each independently. , A hydrogen atom or a monovalent hydrocarbon residue having 1 to 8 carbon atoms, l is 1
The integers of 4 and p and m are the same as those in the above formula (5). ) And a polyoxyalkylene compound having an ester-forming functional group at the terminal. Specifically, polyoxyalkylene glycols such as polyethylene glycol, polyethylene glycol biscarboxymethyl ether, polypropylene glycol and polytetramethylene glycol can be preferably mentioned.

The polyoxyalkylene component (B) has a number average molecular weight of 300 or more. When the molecular weight is less than 300, the melting point of the aliphatic polyester copolymer (C) becomes low, which makes it impractical and also makes it difficult to increase the molecular weight. The number average molecular weight is preferably 600 or more, more preferably 1000 or more. The upper limit of the number average molecular weight is not particularly limited, but is practically 50,000.

The above-mentioned aliphatic polyester (A) in the aliphatic polyester copolymer (C) is 20 to 90% by weight, and the polyoxyalkylene component (B) is 80 to 10% by weight. Thus, a swellable biodegradable hydrogel having excellent mechanical strength can be obtained. In particular, when the proportion of the polyoxyalkylene component (B) exceeds 80% by weight, the hydrolysis rate is too high and the handleability becomes poor. Also,
If it is less than 10% by weight, it does not swell so much when immersed in water, and sufficient performance as a hydrogel cannot be exhibited. The proportion of the polyoxyalkylene component (B) in the aliphatic polyester copolymer (C) is preferably from the viewpoint of handleability, mechanical strength and performance as a hydrogel of the obtained polyoxyalkylene copolymerized aliphatic polyester. Thirty
To 75% by weight, more preferably 40 to 70% by weight
It is.

The above aliphatic polyester copolymer (C)
Is an aliphatic dicarboxylic acid, an acid anhydride of the aliphatic dicarboxylic acid, an alkyl ester of the aliphatic dicarboxylic acid,
Alternatively, a conventionally known method of esterifying or transesterifying the mixture of these with the aliphatic diol, and then, for example, adding the polyoxyalkylene compound having an ester-forming functional group at the terminal to the reaction system and performing melt polycondensation However, the method for producing the aliphatic polyester copolymer (C) is not limited to this.

According to the present invention, the above-mentioned aliphatic polyester copolymer (C) is first prepared, and then the formula (1),
By adding at least one compound (D) selected from the compounds represented by (2) and (3) and performing a melt reaction, an aliphatic polyester having a high degree of polymerization and having a large amount of polyoxyalkylene copolymerized can be rapidly produced. It can be manufactured.

Here, the aliphatic polyester copolymer (C) has a reduced viscosity of 1.0 or more and less than 1.8. This reduced viscosity was 1.1 in a phenol / 1,1,2,2-tetrachloroethane mixed solvent (weight ratio 6/4).
It is a value measured at 2 g / dl and a temperature of 35 ° C. When the reduced viscosity is less than 1.0, the degree of polymerization when the compound (D) is reacted is insufficient, which is not preferable. The reduced viscosity of the aliphatic polyester copolymer (C) is preferably 1.2 or more, more preferably 1.5 or more.

In the present invention, the aliphatic polyester copolymer (C) is reacted with a compound selected from the following formulas (1) to (3).

[0034]

Embedded image Ar-OOC-R-COO-Ar (1) (In the formula (1), R is a divalent aliphatic residue having 2 to 8 carbon atoms, and Ar is 6 to 6 carbon atoms. 12 represents the aryl group.)

[0035]

Embedded image

(In the formula (2), R'is a divalent aliphatic residue having 2 to 8 carbon atoms, and n is an integer of 3 to 11.)

[0037]

Embedded image

(In the formula (3), Ar 'has 6 to 12 carbon atoms.
Represents an aryl group. In the above formula (1), R represents a divalent aliphatic residue having 2 to 8 carbon atoms, and specific examples thereof include ethylene, trimethylene, tetramethylene, hexamethylene, octamethylene and cyclohexylene. You can Ar represents an aryl group having 6 to 12 carbon atoms, and specific examples thereof include phenyl, tolyl, and naphthyl. A
Of these, phenyl is preferable as r.

Specific examples of the compound represented by the above formula (1) include aliphatic dicarboxylic acid diaryl esters such as diphenyl succinate, diphenyl glutarate, diphenyl adipate and diphenyl sebacate.

In the above formula (2), R'represents a divalent aliphatic residue having 2 to 8 carbon atoms, specifically, ethylene, trimethylene, tetramethylene, hexamethylene,
Octamethylene, cyclohexylene and the like can be mentioned. n is an integer of 3-11.

The compound can be obtained by a conventionally known method. For example, it can be easily obtained by subjecting a dicarboxylic acid dihalide to an acylation reaction of 2 mol times the amount of lactam.

Specific examples of the compound represented by the above formula (2) include N, N'-succinylbis-ε-caprolactam, N, N'-glutaroylbis-ε-caprolactam and N, N'-. Adipoylbis-ε-caprolactam,
Preferable examples include lactam compounds such as N, N′-sebacoil bis-ε-caprolactam.

In the above formula (3), Ar 'represents an aryl group having 6 to 12 carbon atoms, specifically, phenyl,
Trill, naphthyl and the like can be mentioned.

Specific examples of the compound represented by the above formula (3) include carbonic acid diesters such as diphenyl carbonate and diparatolyl carbonate.

The compounds represented by the above formulas (1) to (3) may be used alone or in combination of two or more kinds.

When the compound represented by the above formula (1) is used as the above compound, the component derived from the compound is the aliphatic polyester in the polyoxyalkylene copolymerized aliphatic polyester finally obtained ( It is preferable because it is the same as the component of A).

The compound represented by the above formula (2) is
Since the reactivity is high, the final polymer can be obtained in a short time, and it can be preferably used in terms of productivity.

According to the present invention, the aliphatic polyester copolymer (C) is reacted with at least one compound (D) selected from the compounds represented by the above formulas (1), (2) and (3). In doing so, an amount satisfying the following formula (4) is added, and the melting reaction is performed under reduced pressure or in an inert gas atmosphere.

[0049]

Equation 3] ^{0.1WX ≦ 10 4 Y ≦ 2.0WX (} 4) the formula (4) in, OH end groups X is the amount of compound (D) before addition of the aliphatic polyester copolymer (C) (mol / 10 ⁶
g) and Y represent the added amount of the compound (D) (% by weight / polymer), and W represents the molecular weight of the component (D). Compound (D)
When the addition amount Y of is out of the range of the formula (4), the effect of increasing the degree of polymerization becomes insufficient and the effect as a hydrogel is not sufficient.

The melting reaction is carried out in the presence of a polycondensation catalyst under reduced pressure or in an inert gas atmosphere. Here, as the polycondensation catalyst, those conventionally known in the art can be used, for example, antimony compounds such as antimony oxide, tin acetate, tin compounds such as dibutyltin oxide, titanium compounds such as tetraalkoxytitanate, and zinc acetate. And zinc compounds, calcium compounds such as calcium acetate, manganese compounds such as manganese acetate, and alkali metal compounds such as sodium carbonate and potassium carbonate. The amount of these polycondensation catalysts used is preferably about 0.001 to 0.1 mol% and more preferably about 0.005 to 0.05 mol% based on the dicarboxylic acid component used. As the polycondensation catalyst, it is preferable to use the catalyst used for producing the polyester (A) from the aliphatic dicarboxylic acid and the aliphatic diol as it is, and in that case, the above-mentioned formulas (1), (2) and (3) are used. It is not necessary to newly add at least one kind of compound (D) selected from the compounds represented by the formula (1) when adding and reacting.

When this melting reaction is carried out using the compound (D) represented by the above formula (1) as one component, the compound does not vaporize and the compound and the aliphatic polyester copolymer are The aromatic monohydroxy compound produced by the reaction with the terminal OH group of (C) is preferably rapidly distilled out of the reaction system, and from this point, it is preferable to carry out the melt reaction under a suitable reduced pressure.

On the other hand, when the melting reaction is carried out using the compound represented by the above formula (2), the compound and the aliphatic polyester copolymer (C) are not volatilized in some cases. It is preferable that the cyclic lactam compound produced by the reaction with the terminal OH group be rapidly distilled out of the reaction system, and from this point, it may be preferable to carry out the melt reaction under an appropriate reduced pressure. The compound represented by the formula (2) is a terminal OH of the aliphatic polyester copolymer (C).
The ring-opening reaction with the group is not limited to this, and an inert gas atmosphere may be used. These largely depend on the catalyst used. For example, the former reaction is likely to occur in a tin compound such as dibutyltin diacetate and the latter reaction is likely to occur in a titanium compound such as tetraalkoxytitanate.

When the melt reaction is carried out using the compound represented by the above formula (3), the compound (D) does not volatilize and the compound and the aliphatic polyester copolymer (C) are used. It is preferable that the aromatic monohydroxy compound produced by the reaction with the terminal OH group or COOH group is rapidly distilled out of the reaction system, and from this point, it is preferable to carry out the melt reaction under an appropriate reduced pressure.

The melting reaction temperature in the present invention is not particularly limited, but is preferably about 160 to 260 ° C., 180
It is more preferable to set the temperature to about 250 ° C.

The reaction time at that time is not particularly limited, and it varies depending on the kinds of the aliphatic polyester copolymer (C) and the compound (D) used and the reaction temperature, but it is generally about 5 to 120. It is preferably about 10 minutes, more preferably about 10 to 60 minutes.

According to the production method of the present invention, the reduced viscosity is 1.8.
The above polyoxyalkylene copolymerized aliphatic polyester having a high degree of polymerization can be easily produced. If the reduced viscosity is less than 1.8, the mechanical strength and toughness of the polymer will be insufficient and the range of use will be greatly limited. The reduced viscosity of the obtained polyoxyalkylene copolymerized aliphatic polyester is preferably 2.0 or more, more preferably 2.3 or more.

[0057]

EFFECTS OF THE INVENTION According to the method of the present invention, it is difficult to obtain a polymer having sufficient mechanical properties by the usual melt polymerization method. A large amount of polyoxyalkylene component having a number average molecular weight of 300 or more is contained. It is possible to efficiently produce the aliphatic polyester copolymer copolymerized with. Specifically, a polyoxyalkylene component having a number average molecular weight of 300 or more is copolymerized at 80 to 10% by weight, and an aliphatic polyester copolymer having a specific viscosity range is prepared, and then the aliphatic dicarboxylic acid is added to the polymer. By adding a specific amount of a compound selected from a diaryl ester, a lactam compound and a carbonic acid diester and performing a melt reaction, a polymer having a high degree of polymerization can be easily and rapidly produced.

The polyoxyalkylene copolymerized aliphatic polyester obtained has excellent productivity and thus a good hue. Furthermore, since it is a polymer having a high degree of polymerization that exhibits sufficient mechanical properties and has sufficient toughness, it can be advantageously used as a plastic, a fiber, a film, a sheet, or the like. It can also be used as a hydrogel having a high degree of swelling that is easily decomposed.

Such a polymer is particularly useful as a container, a packaging material, a disposable material, and other various applications utilizing biodegradability, and its industrial significance is great. In addition, since the polymer is excellent in biocompatibility and biodegradability, the performance as a hydrogel is effectively used for implant, sustained drug release,
It is useful for medical applications such as contact lenses.

[0060]

The present invention will be described below with reference to examples, but the present invention is not limited thereto. `` Parts '' in the examples
Means "parts by weight".

The reduced viscosity (ηsp / C) is phenol / 1,
1,2,2-Tetrachloroethane mixed solvent (weight ratio 6 /
In 4), it was measured at a concentration of 1.2 g / dl and a temperature of 35 ° C.

The amount of COOH end groups is 100 mg of polymer.
Was dissolved in 10 ml of chloroform at room temperature for 20 minutes, 10 ml of benzyl alcohol was added, and titration was performed with a 0.1 N sodium hydroxide benzyl alcohol solution using phenol red as an indicator.

The amount of the OH end group was 500 mg of the polymer and 500 mg of succinic anhydride were melt-reacted at 120 ° C. to convert the end into COOH, and the polymer was purified by reprecipitation from a chloroform solution into ethanol. The amount was determined by measuring according to the method described above.

The melting point (Tm) of the polymer was measured by DSC at a temperature rising rate of 10 ° C./min.

The values of 0.1 WX, 10 ⁴ Y and 2.0 WX in the above formula (4) in each example are shown in Table 1 below.

[Example 1] Dimethyl succinate 19.9
Parts, tetramethylene glycol 30.3 parts and tetrabutyl titanate 0.014 parts were charged into a reaction vessel equipped with a distillation system through a rectification column, and finally the internal temperature of the reaction vessel was adjusted to 2
It was gradually heated to 10 ° C. When the distillation of methanol was completed, the transesterification reaction was stopped and the reaction product was
Transferred to a reaction vessel equipped with stirrer and vacuum distillation system. Next, polyethylene glycol biscarboxymethyl ether (average molecular weight 1,000, Wako Pure Chemical Industries, Ltd.) 23.0
Part in this reactor, and then 230 ° C in a nitrogen stream under normal pressure.
For 25 minutes, then at the same temperature for 30 minutes 0.12 mm
A vacuum condition of Hg was set, and the melting reaction was further performed for 160 minutes under the same condition. The obtained polymer is ηsp / C1.64, COO
The amount of H end groups was 15 mol / 10 ⁶ g, the amount of OH end groups was 206 mol / 10 ⁶ g, and the Tm was 92.4 ° C.

With respect to the polymer obtained by the above method,
0.35 parts of diphenyl carbonate was added in a molten state under normal pressure, and the mixture was melt-reacted under normal pressure in a nitrogen stream at 230 ° C. for 5 minutes and then at the same temperature for 30 minutes under vacuum conditions of 0.2 mmHg.
The polymer obtained after the reaction has ηsp / C2.69 and Tm9.
The copolymerization ratio of the polyoxyalkylene components was 0.5% at 50% by weight.

Example 2 Dimethyl succinate 22.1
Parts, 30.8 parts of tetramethylene glycol and 0.02 parts of tetrabutyl titanate were placed in the same reaction vessel as in Example 1 and gradually heated until the inner temperature of the reaction vessel finally reached 215 ° C. When the distillation of methanol was completed, the transesterification reaction was stopped, and 28.0 parts of polyethylene glycol biscarboxymethyl ether (average molecular weight 1,000, manufactured by Wako Pure Chemical Industries, Ltd.) was added, and then the polymerization reaction was carried out in the same manner as in Example 1. (0.2 mmHg, 150 minutes). The polymer obtained has ηsp / C1.34 and a COOH end group content of 5
Mol / 10 ⁶ g, OH terminal group amount 227 mol / 10 ⁶ g, T
m was 88.7 ° C.

With respect to the polymer obtained by the above method,
0.39 parts of diphenyl adipate was added in a molten state under normal pressure, and the mixture was melt-reacted under normal pressure in a nitrogen stream at 230 ° C. for 3 minutes and then at the same temperature for 60 minutes under a vacuum condition of 0.25 mmHg. The polymer obtained after the reaction has ηsp / C2.04, Tm
87.8 ° C., copolymerization ratio of polyoxyalkylene component 52
% By weight.

Example 3 The transesterification reaction and the polymerization reaction were carried out in the same manner as in Example 2. The obtained polymer is ηsp
/C1.60, COOH end group amount 10 mol / 10 ⁶ g,
The amount of OH end groups was 210 mol / 10 ⁶ g, and the Tm was 90.2 ° C. N, N′-succinylbis-ε for the polymer
-0.48 parts of caprolactam was added and the reaction was carried out as in Example 2 (0.2 mmHg, 20 minutes). The polymer obtained after the reaction has ηsp / C 2.80 and Tm 89.0.
The copolymerization ratio of the polyoxyalkylene component at 52 ° C was 52% by weight.

Comparative Example 1 Transesterification reaction and polymerization reaction (0.2 mmHg, 180 minutes) in the same manner as in Example 2 except that finally diphenyl carbonate was not added.
However, only a polymer having ηsp / C1.67 (melting point 87.4 ° C.) was obtained.

Example 4 Dimethyl succinate 15.0
Parts, 22.3 parts of tetramethylene glycol and 0.01 parts of tetrabutyl titanate were placed in the same reaction container as in Example 1 and gradually heated until the internal temperature of the reaction container finally reached 213 ° C. When the distillation of methanol was completed, the transesterification reaction was stopped, 42.3 parts of polyethylene glycol biscarboxymethyl ether (average molecular weight 1,000, manufactured by Wako Pure Chemical Industries, Ltd.) was added, and then the polymerization reaction was carried out in the same manner as in Example 1. (0.18 mmHg, 210 minutes). The obtained polymer had ηsp / C1.71, a COOH end group amount of 20 mol / 10 ⁶ g, and an OH end group amount of 195 mol / 10.
⁶ g, Tm 58.6 ° C.

For the polymer obtained by the above method,
0.39 parts of diphenyl adipate was added in a molten state under normal pressure, and the mixture was melt-reacted under normal pressure in a nitrogen stream at 230 ° C. for 3 minutes and then at the same temperature for 60 minutes under a vacuum condition of 0.17 mmHg. The polymer obtained after the reaction has ηsp / C2.31, Tm
57.8 ° C., copolymerization ratio of polyoxyalkylene component 71
% By weight.

Comparative Example 2 The same transesterification reaction and polymerization reaction (0.2 mmHg, 300 minutes) were carried out as in Example 4, except that diphenyl adipate was not added finally. However, ηsp / C 1.77 (Tm 60.1 ° C)
No polymer was obtained.

Example 5 Dimethyl succinate 19.6
Parts, 28.0 parts of tetramethylene glycol and 0.014 parts of tetrabutyl titanate were placed in the same reaction container as in Example 1 and gradually heated until the internal temperature of the reaction container finally reached 220 ° C. When the distillation of methanol was completed, the transesterification reaction was stopped and PEG (average molecular weight 1,0
00) 23.7 parts, and then the polymerization reaction was carried out in the same manner as in Example 1 (0.15 mmHg, 180 minutes). The obtained polymer has ηsp / C1.62 and COOH end group amount of 16
Mol / 10 ⁶ g, OH end group amount 208 mol / 10 ⁶ g, T
m was 76.2 ° C.

With respect to the polymer obtained by the above method,
0.46 parts of diphenyl adipate was added in a molten state under normal pressure, and the mixture was melt-reacted under normal pressure in a nitrogen stream at 230 ° C. for 3 minutes and then at the same temperature for 30 minutes under a vacuum condition of 0.2 mmHg.
The polymer obtained after the reaction has ηsp / C2.75 and Tm7.
The copolymerization ratio of the polyoxyalkylene components was 3.5% at 51% by weight.

Example 6 The transesterification reaction and the polymerization reaction were carried out in the same manner as in Example 5. The obtained polymer is ηsp
/C1.60, COOH end group amount 15 mol / 10 ⁶ g,
The amount of OH end groups was 214 mol / 10 ⁶ g, and the Tm was 76.0 ° C. N, N′-adipoylbis-ε for the polymer
-0.46 parts of caprolactam was added and the reaction was carried out as in Example 5 (0.2 mmHg, 15 minutes). The polymer obtained after the reaction has ηsp / C2.78 and Tm74.1.
The copolymerization ratio of the polyoxyalkylene component at 51 ° C was 51% by weight.

[Comparative Example 3] In Example 5, finally, N,
The same transesterification reaction and polymerization reaction (0.12 m) except that N'-adipoylbis-ε-caprolactam was not added.
mHg, 240 minutes). However, ηsp
Only a polymer of /C1.58 (melting point 77.5 ° C) was obtained.

[0079]

[Table 1]

Claims (1)

[Claims] 1. An aliphatic polyester (A) comprising 20 to 90% by weight of an aliphatic dicarboxylic acid component having 4 to 10 carbon atoms and an aliphatic diol component having 2 to 6 carbon atoms, and a number average molecular weight. Concentration 1.2 g / in reduced viscosity (phenol / 1,1,2,2-tetrachloroethane mixed solvent (weight ratio 6/4)) composed of 80 to 10% by weight of 300 or more polyoxyalkylene component (B) dl, measured at a temperature of 35 ° C.) The aliphatic polyester copolymer (C) having a value of 1.0 or more and less than 1.8 is added to the group consisting of compounds represented by the following formulas (1), (2) and (3). Reduced viscosity, characterized in that at least one selected compound (D) is added in an amount satisfying the following formula (4) and melt-reacted in the presence of a polycondensation catalyst under reduced pressure or in an inert gas atmosphere. 1.8 or higher Method for producing lyoxyalkylene copolymerized aliphatic polyester. Embedded image Ar-OOC-R-COO-Ar (1) (In the formula (1), R is a divalent aliphatic residue having 2 to 8 carbon atoms, and Ar is 6 to 6 carbon atoms. 12 represents an aryl group.) (In the formula (2), R ′ is a divalent aliphatic residue having 2 to 8 carbon atoms, and n is an integer of 3 to 11.) (In the formula (3), Ar ′ represents an aryl group having 6 to 12 carbon atoms.) ## EQU1 ## 0.1WX ≦ 10 ⁴ Y ≦ 2.0WX (4) (In the formula (4), X is a compound) (D) OH end group amount of the aliphatic polyester copolymer (C) before addition (mol / 10
⁶ g), Y represents the amount of compound (D) added (% by weight / polymer, and W represents the molecular weight of compound (D)).