JPH10204167A - High-molecular-weight polyester and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyester improved in tearability by selecting a polyester having such a specified number average mol.wt. that the elongation at break is a specified value or higher when measured at a specified pulling speed. SOLUTION: An aliph. glycol (e.g. 1,2-hexanediol) having a branched hydrocarbon group is thermally reacted with an aliph. dicarboxylic acid (e.g. succinic anhydride) having no branched hydrocarbon group to give a branched oligomer. Separately, succinic anhydride is thermally reacted with an aliph. glycol (e.g. ethylene glycol) having no branched hydrocarbon group under a reduced pressure to give a low-mol.-wt. polyester. The above-obtd. oligomer and polyester are mixed and reacted with each other at 180-280 deg.C under a reduced pressure in the presence of a catalyst (e.g. an organotitanium compd.) to give a high-mol.-wt. polymer having a number average mol.wt. of 30,000-200,000 and an elongation at break of 10% or higher when measured at a pulling speed of 1,000mm/min according to the plastic tensile test method (ASTM D882-90A).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a high molecular weight aliphatic polyester, a method for producing the same, and a molded product.
More specifically, the present invention relates to a high-molecular-weight polyester having improved “easiness of tearing”, a production method thereof, and a molded product.

[0002]

2. Description of the Related Art Aliphatic polyesters are generally recognized as biodegradable, and are expected to be used alone or in combination with various additives in molded articles such as fibers, sheets and films. In particular, when used for a sheet or a film, not only a sufficient strength is required, but also a property that is difficult to tear is required.

As a method for producing an aliphatic polyester, a method of directly esterifying a dicarboxylic acid and a glycol, a method of transesterifying an alkyl ester of a dicarboxylic acid and a glycol to obtain a glycol ester and / or a low polymer thereof, Next, a method of heating and stirring the mixture under high vacuum for a long time to perform polycondensation is known.

However, the aliphatic polyesters obtained by these methods have a number-average molecular weight of 30,000 or less, and only those which easily tear when molded into sheets or films.

Conventionally, as a method for improving the "easiness of tearing", for example, Japanese Patent Application Laid-Open No. 5-295071 discloses the use of a tri- or higher functional copolymer component. It is dangerous and is not an industrial manufacturing method. Even if it could be manufactured, the gel was mixed in the product, which was not suitable for practical use.

[0006] In addition, no practical method of evaluating "easiness of tearing" has been known so far, and a plastic tensile test (JIS K7113, AS
Although TMD638) is generally widely used, such a test method can determine the strength, the elastic modulus, and the elongation, but cannot evaluate the actual “teariness”.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and has a high molecular weight fat having improved tearability, which can be used as sheets, films and other molded products. It is an object of the present invention to provide an aliphatic polyester, a method for producing the same, and a molded article containing the high-molecular-weight aliphatic polyester.

[0008]

Means for Solving the Problems The present inventors have intensively studied a method capable of quantitatively measuring the actual easiness of tearing, and as a result, have found that a tensile test (ASTM-D882-
90 (Method A)) was found to be proportional to the actual "easiness of tearing" when measured at a tensile speed of 1000 mm / min.

As a result of evaluation by this method, an aliphatic polyester having a number average molecular weight of less than 30,000 is easily broken,
It turned out to be impractical.

A high molecular weight comprising 1 to 100 mol% of an aliphatic ester unit having a branched hydrocarbon group (A) and 0 to 99 mol% of an aliphatic ester unit having a linear hydrocarbon group (B). It has been found that aliphatic polyesters can improve the "teariness".

That is, the present invention provides a plastic having a number average molecular weight of 30,000 to 20,000 having a breaking elongation of 10% or more as measured at a tensile strength of 1000 mm / min in a tensile test (ASTM-D882-90 (Method A)).
0 high molecular weight aliphatic polyester (I).

In another aspect of the present invention, the present invention relates to an aliphatic ester unit having a branched hydrocarbon group (A) in an amount of from 1 to 100 mol% and a linear hydrocarbon group having an aliphatic ester unit (B) in an amount of 0 to 100 mol%. Number average molecular weight of 300 comprising ~ 99 mol%
00 to 200,000 high molecular weight aliphatic polyester (I
I).

For example, the high molecular weight aliphatic polyester contains an aliphatic dicarboxylic acid component containing an aliphatic dicarboxylic acid having a branched hydrocarbon group and / or an anhydride thereof and a cyclic acid anhydride, and a cyclic ether. It is a high molecular weight aliphatic polyester obtained by subjecting an aliphatic glycol component to ring-opening polymerization.

Further, the invention of the production method of the present invention includes the following (1)
To (3).

(1) Fat containing aliphatic carboxylic acid having two carboxyl groups in the molecule and having a branched hydrocarbon group having 2 or more carbon atoms to which the carboxyl group is bonded and / or an anhydride thereof A method for producing the high-molecular-weight aliphatic polyester, which comprises reacting an aliphatic dicarboxylic acid component with an aliphatic glycol component. (2) an aliphatic dicarboxylic acid component having two hydroxyl groups in a molecule; (3) a method for producing the high molecular weight aliphatic polyester, which comprises reacting an aliphatic glycol component containing an aliphatic glycol having a branched hydrocarbon group having 2 or more carbon atoms to which a hydroxyl group is bonded. An aliphatic carboxylic acid having two carboxyl groups and having a branched hydrocarbon group having 2 or more carbon atoms to which the carboxyl groups are bonded, and / or An aliphatic dicarboxylic acid component containing a product, and an aliphatic glycol component containing an aliphatic glycol having two hydroxyl groups in a molecule and having a branched hydrocarbon group having 2 or more carbon atoms to which the hydroxyl group is bonded, Wherein the aliphatic dicarboxylic acid component contains a cyclic acid anhydride, wherein the aliphatic dicarboxylic acid component contains a cyclic acid anhydride, In addition, it is preferable that the aliphatic glycol component contains a cyclic ether because it can be efficiently produced.

The molded article of the present invention also relates to a molded article containing the high-molecular-weight aliphatic polyester.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION High Molecular Weight Aliphatic Polyester As a method for measuring the elongation at break of the high molecular weight aliphatic polyester of the present invention, a plastic tensile test (ASTM-D
882-90 (Method A)) and a pulling speed of 100
The elongation at break when a tensile test was performed at 0 mm / min was measured. Specifically, for example, a high molecular weight aliphatic polyester,
Molding temperature 130 ° C, molding pressure 150 using a compression molding machine
Molding under conditions of kgf / cm ² and molding time of 2 minutes,
A film having a thickness of 200 μm was prepared, this film was punched out with a dumbbell, and measured by performing a tensile test at a tensile speed of 1000 mm / min.

The high-molecular-weight aliphatic polyester (I) of the present invention has a tensile speed of 1000 mm in the above method.
The elongation at break as measured in / min is 10% or more, preferably 50% or more, and more preferably 100% or more.
When the elongation at break is less than 10%, a film which is very easily torn without being able to absorb the impact when a sharp force is applied or a sharp object is hit cannot be absorbed.

The high-molecular-weight aliphatic polyester (I) of the present invention further has a pulling speed of 100 in the above method.
Breaking strength of 10 kgf / c when measured at 0 mm / min
m ² or more, preferably 50 kgf / cm ² or more, more preferably 100 kgf / cm ² or more, from the viewpoint of obtaining a film more resistant to breakage.

Further, the high-molecular-weight aliphatic polyester (I) of the present invention further has a pulling speed of 100 in the above method.
200 kgf tensile modulus when measured at 0 mm / min
/ Mm ² or less, preferably 100 kgf / mm ² or less, from the viewpoint that the film becomes more flexible.

The other high molecular weight polyesters of the present invention (I
I) includes 1 to 100 mol% of an aliphatic ester unit having a branched hydrocarbon group (A) and 0 to 99 mol% of an aliphatic ester unit having a linear hydrocarbon group (B). Is a high molecular weight aliphatic polyester.

Examples of the branched hydrocarbon group include propylene, ethylethylene, 1,2-dimethyl-ethylene, methylmethylene, 2-methyl-tetramethylene, octadecylethylene, and 1-methyl-trimethylene. , Propylethylene group, 1,3-dimethyl-trimethylene group, butylethylene group, 2,5-dimethyl-tetramethylene group, 2,2-dimethyl-trimethylene group,
1,1,3,3-tetramethyl-trimethylene group, 1,
1,4,4-tetramethyl-tetramethylene group, 1-butyl-2-ethyl-trimethylene group, 2,2-dimethyl-3-isopropyl-trimethylene group, 2-butyl-2
-Ethyl-1,3-trimethylene group, decanylethylene group, dodecanylethylene group, groups obtained by removing hydroxyl groups from dipropylene glycol, and the like.

Examples of the linear hydrocarbon group include ethylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, decamethylene, and octadecamethylene. .

The aliphatic ester units (A) and (B) may contain a group other than a hydrocarbon group such as an ether group, a ketone group and a sulfide group.

The high molecular weight aliphatic polyester of the present invention has a number average molecular weight of 30,000 to 200,000.
It is preferably 40,000 to 150,000, more preferably 50,000 to 100,000. In order to use an aliphatic polyester as a film, sheet, or other molded product, the number average molecular weight must be at least 30,000 or more. If it is lower than this, it is brittle, or there is an industrial problem such as inability to stretch, it is possible to increase the molecular weight by reacting with a chain extender, but the process becomes multi-step,
It is industrially disadvantageous because the used chain extender causes fisheye of the film. In consideration of thermal deterioration and strength, the number average molecular weight of the high molecular weight aliphatic polyester is preferably 40,000 or more, more preferably 50,000 or more. On the other hand, if the number average molecular weight is set to 200,000 or more, it takes a long time for the reaction, which is industrially disadvantageous. The number-average molecular weight is 200,000 or less, preferably 150,000 or less, and more preferably 100,000 or less, because a long-term reaction increases the generated volatile components.

The method for obtaining the high molecular weight aliphatic polyester of the present invention is not particularly limited, and specific production methods thereof include the following production methods (1) to (3) of the present invention.
Is preferable, and particularly, an aliphatic dicarboxylic acid component containing an aliphatic dicarboxylic acid having a branched hydrocarbon group and / or an anhydride thereof and a cyclic acid anhydride, and an aliphatic glycol component containing a cyclic ether. The method of ring-opening polymerization is preferred in terms of production efficiency. Succinic anhydride is particularly preferred as the cyclic acid anhydride, and ethylene oxide is particularly preferred as the cyclic ether. The cyclic ether may have a branched hydrocarbon group.

The high-molecular-weight aliphatic polyester of the present invention may contain, if necessary, other components such as a crystal nucleating agent, a pigment, a dye, a heat-resistant agent, a coloring inhibitor, an antioxidant, a weathering agent, a lubricant,
Antistatic agents, stabilizers, fillers, reinforcing materials, flame retardants, plasticizers, and other polymers can be added as long as the effects of the present invention are not impaired.

The high molecular weight aliphatic polyester of the present invention comprises
It can be applied to ordinary molding methods such as extrusion molding, injection molding, hollow molding, vacuum molding and the like, and can be molded products such as various parts, containers, materials, appliances, films, sheets, fibers, nonwoven fabrics and the like.

Method for Producing High Molecular Weight Aliphatic Polyester The invention of the method for producing a high molecular weight aliphatic polyester of the present invention relates to the following (1) to (3).

(1) Fat containing aliphatic carboxylic acid having two carboxyl groups in the molecule and having a branched hydrocarbon group having 2 or more carbon atoms to which the carboxyl group is bonded and / or an anhydride thereof A method for producing the high-molecular-weight aliphatic polyester, which comprises reacting an aliphatic dicarboxylic acid component with an aliphatic glycol component. (2) an aliphatic dicarboxylic acid component having two hydroxyl groups in a molecule; Reacting an aliphatic glycol having a branched hydrocarbon group having 2 or more carbon atoms to which a hydroxyl group is bound and / or an aliphatic glycol component containing an epoxide thereof; 3) an aliphatic hydrocarbon having two carboxyl groups in the molecule and having a branched hydrocarbon group having 2 or more carbon atoms to which the carboxyl groups are bonded; An aliphatic dicarboxylic acid component containing boric acid and / or an anhydride thereof, an aliphatic glycol having two hydroxyl groups in a molecule and a branched hydrocarbon group having 2 or more carbon atoms to which the hydroxyl groups are bonded, and And / or an aliphatic glycol component containing the epoxide,
The method for producing the high-molecular weight aliphatic polyester characterized by reacting the aliphatic dicarboxylic acid having a branched hydrocarbon group or an anhydride thereof, for example, methyl succinic acid, ethyl succinic acid, dimethyl succinic acid, methyl malonic acid, 3-methyladipic acid, octadecyl succinic anhydride and the like.

The aliphatic dicarboxylic acid component referred to in the present invention includes, in addition to the aliphatic dicarboxylic acid having a branched hydrocarbon group or its anhydride, succinic acid, adipic acid, suberic acid, sebacic acid, azelaic acid, decane acid Dicarboxylic acids such as dicarboxylic acid, octadecane dicarboxylic acid and dimer acid; esters of these dicarboxylic acids; succinic anhydride, maleic anhydride, itaconic anhydride, glutaric anhydride, adipic anhydride, citraconic anhydride, phthalic anhydride, and trianhydride Melitic acid, pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride, butane-1,
2,3,4-tetracarboxylic dianhydride, maleic anhydride homopolymer, maleic anhydride-vinyl acetate copolymer,
Maleic anhydride-ethylene copolymer, maleic anhydride-
Acid anhydrides such as isobutylene copolymer, maleic anhydride-isobutyl vinyl ether copolymer, maleic anhydride-acrylonitrile copolymer, and maleic anhydride-styrene copolymer are exemplified. Further, a part of the dicarboxylic acid or its ester or an acid anhydride thereof may be changed to one selected from a difunctional or higher functional polycarboxylic acid and its anhydride, and a trifunctional or higher functional oxycarboxylic acid. Malic acid as trifunctional or higher oxycarboxylic acid,
Tartaric acid, citric acid and the like can be mentioned. Above all, in order to produce a polyester in which an acid component and an alcohol component are linearly bonded, a polyester having two carboxyl groups in one molecule is preferable.

The proportion of the branched aliphatic dicarboxylic acid and / or anhydride used is 1 to 40% by weight, preferably 5 to 30% by weight, based on the whole aliphatic dicarboxylic acid component. The above range is preferable because there is no decrease in the melting point and there is an effect of improving the easiness of tearing.

Examples of the aliphatic glycol having a branched hydrocarbon group include 1,2-propanediol, dipropylene glycol, 1,2-butanediol,
3-butanediol, 2,3-butanediol, 1,2
-Pentanediol, 2,4-pentanediol, 1,
2-hexanediol, 2,5-hexanediol,
2,2-diethyl-1,3-propanediol, 2,4
-Dimethyl-2,4-pentanediol, 2,5-dimethyl-2,5-hexanediol, 2-ethyl-1,3
-Hexanediol, 2,2,4-trimethyl-1,3
-Pentanediol, 2-butyl-2-ethyl-1,3
-Propanediol, 1,2-dodecanediol, 1,
2-tetradecanediol and the like, and as the epoxide of these glycols, propylene oxide, 1,
Examples thereof include 2-epoxybutane and 2,3-epoxybutane.

The aliphatic glycol component referred to in the present invention includes, in addition to the aliphatic glycol having a branched hydrocarbon group, ethylene glycol, propylene glycol,
3-propanediol, 1,4-butanediol, 1,
Glycols such as 5-pentanediol, 1,6-hexanediol and decamethylene glycol; and epoxides of the glycol. It is also possible to use polyoxyalkylene glycol as a part of the glycol component, and examples thereof include polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol and copolymers thereof. It is also possible to use a trifunctional or higher polyhydric alcohol as a part of the glycol component. In particular, in order to form a polyester in which an acid component and an alcohol component are linearly bonded, a polyester having two hydroxyl groups in one molecule is preferable. Examples of the polyhydric alcohol include glycerin, trimethylolpropane, and pentaerythritol. It is also possible to use diepoxide as a part of the glycol component, for example, (poly) ethylene glycol diglycidyl ether, (poly) propylene glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, resorcin diglycidyl ether, Neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, adipic acid diglycidyl ester,
ο-Diglycidyl phthalate, diglycidyl terephthalate, hydroquinone diglycidyl ether, bisphenol S diglycidyl ether, glycerol diglycidyl ether, sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl Ether, diglycerol polyglycidyl ether, triglycidyl tris (2-hydroxyethyl) isocyanurate, glycerol triglycidyl ether, trimethylolpropane polyglycidyl ether and the like.

The proportion of the branched aliphatic glycol and / or its epoxide is from 1 to 40% by weight, preferably from 5 to 30% by weight, based on the entire aliphatic glycol component.
It is. The above range is preferable because there is no decrease in the melting point and there is an effect of improving the easiness of tearing.

In the production method of the present invention, the reaction method is not particularly limited and may be appropriately selected depending on the raw materials. Examples thereof include: (i) polycondensation of dicarboxylic acid or its ester or its anhydride with glycol. (Ii) a method of subjecting a cyclic acid anhydride and a cyclic ether to ring-opening polymerization, followed by polycondensation.

In the production of the high-molecular-weight aliphatic polyester by the method (i), the total amount of the dicarboxylic acid (or ester thereof) component and the glycol component may be initially mixed and reacted, or as the reaction proceeds, the division may be carried out. It can be added even if it is added. As the polycondensation reaction, a normal esterification reaction is performed, and then the degree of polymerization is increased by a transesterification method. At this time, the distinction between the esterification reaction and the transesterification reaction does not necessarily need to be clear.

In the esterification reaction and transesterification reaction, it is usually necessary to use a small amount of a catalyst. When the esterification method and the transesterification reaction by dehydration condensation are used in combination,
It is also possible to carry out ester exchange reaction using a catalyst after carrying out esterification without a catalyst. As a catalyst,
There is no particular limitation as long as it is generally used.
i, Ge, Zn, Fe, Mn, Co, Zr, Hf, V,
Ir, La, Ce, Li, Ca, Mg, Sn, Ba, N
organic metal compounds such as i, organic acid salts, metal alkoxides,
Examples include metal oxides, metal hydroxides, carbonates, phosphates, sulfates, nitrates, and chlorides. The amount of the catalyst to be used is 0.001 to 5 parts by weight, preferably 0.01 to 0.5 parts by weight, based on 100 parts by weight of the usually obtained high molecular weight aliphatic polyester.

In the case of obtaining a poly (condensed) compound by the method (i), there is no problem in the esterification reaction by a known method. For example, a reaction temperature of 180 to 280 ° C. and a normal pressure
The reaction is carried out at a reduced pressure of 1 mmHg, followed by a transesterification reaction. The conditions for the transesterification reaction include:
Reaction temperature 180-280 ° C, preferably 230-270
° C, degree of vacuum 0.5 mmHg or more, preferably 1.0 mm
Hg or more, more preferably 1.0 to 3.0 mmHg. It is. When the reaction temperature is lower than this range, the reaction time becomes extremely long, and when the reaction temperature is higher than this range, it is industrially disadvantageous because of significant coloration and a large amount of volatile components. When the degree of pressure reduction is less than 0.5 mmHg, that is, when a high vacuum is applied, a large amount of by-products and low molecular weight compounds are generated by depolymerization. Due to the reduction in the degree of decompression and the performance of the vacuum pump due to the generation of these volatile components, the reaction time becomes extremely long or the molecular weight does not reach a predetermined value. Further, the yield is remarkably reduced due to generation of volatile components, and even if recovered, these volatile components are not used, and thus become a serious economic problem. Decompression degree is 3.0
When the pressure is lower than mmHg, the reaction time becomes extremely long, which is industrially disadvantageous.

Regarding the method (ii), first, the step of ring-opening polymerization of a cyclic acid anhydride and a cyclic ether will be described below.

It has been known that the cyclic acid anhydride such as succinic anhydride used in the present invention does not homopolymerize. By cyclically adding cyclic ether in the presence of a polymerization catalyst to such a cyclic acid anhydride that is not homopolymerized and polymerizing, a polyester in which an acid component and an alcohol component are substantially copolymerized alternately can be produced in a short time. Can be generated.

The polymerization can be carried out by a method such as polymerization in a solvent or bulk polymerization. In polymerization in a solvent, the cyclic acid anhydride is used by dissolving it in a solvent. In bulk polymerization, the cyclic acid anhydride is melted before use in the present invention.

The polymerization in a solvent can be carried out either batchwise or continuously. Examples of the solvent used include benzene, toluene, xylene, cyclohexane, n
-Inert solvents such as hexane, dioxane, chloroform and dichloroethane.

The polymerization catalyst is not particularly limited, and those usually used in ring-opening polymerization of polyester are used. For example, tetramethoxy zirconium, tetraethoxy zirconium, tetra-iso-propoxy zirconium, tetra-iso-butoxy zirconium, tetra-n-butoxy zirconium, tetra-t-butoxy zirconium, triethoxy aluminum, triethoxy aluminum, tri-n-propoxy aluminum, tri- iso-propoxyaluminum, tri-n-butoxyaluminum, tri-i
So-butoxyaluminum, tri-sec-butoxyaluminum, mono-sec-butoxy-di-iso-
Propoxy aluminum, ethyl acetoacetate aluminum diisopropylate, aluminum tris (ethyl acetoacetate), tetraethoxy titanium, tetra-iso-propoxy titanium, tetra-n-propoxy titanium, tetra-n-butoxy titanium, tetra-se
c-butoxytitanium, tetra-t-butoxytitanium, tri-iso-propoxygallium, tri-iso-propoxyantimony, tri-iso-butoxyantimony, trimethoxyboron, triethoxyboron, triethoxyboron
iso-propoxyboron, tri-n-propoxyboron, tri-iso-butoxyboron, tri-n-butoxyboron, tri-sec-butoxyboron, tri-t-
Butoxyboron, tri-iso-propoxygallium,
Tetramethoxygermanium, tetraethoxygermanium, tetra-iso-propoxygermanium, tetra-n-propoxygermanium, tetra-iso-butoxygermanium, tetra-n-butoxygermanium, tetra-sec-butoxygermanium, tetra-
metal alkoxides such as t-butoxygermanium; antimony pentachloride, zinc chloride, lithium bromide, tin chloride (I
V), halides such as cadmium chloride and boron trifluoride diethyl ether; trimethylaluminum, triethylaluminum, diethylaluminum chloride, ethylaluminum dichloride, tri-iso-
Alkyl aluminum such as butyl aluminum; alkyl zinc such as dimethyl zinc, diethyl zinc, diisopropyl zinc; tertiary amine such as triallylamine, triethylamine, tri-n-octylamine, benzyldimethylamine; phosphotungstic acid, phosphomolybdic acid, silica Heteropoly acids such as tungstic acid and alkali metal salts thereof; zirconium oxychloride, zirconyl octylate, zirconyl stearate, zirconium compounds such as zirconyl nitrate and the like, among which zirconyl octylate, tetraalkoxy zirconium,
Trialkoxy aluminum compounds are particularly preferred. The amount of the polymerization catalyst used is not particularly limited, but is usually 0.001 to 1 based on the total amount of the cyclic acid anhydride and the cyclic ether.
0% by weight. Regarding the method of adding the polymerization catalyst, the polymerization catalyst may be added to the cyclic acid anhydride or may be added sequentially like a cyclic ether.

The polymerization temperature is not particularly limited as long as it is a temperature at which the cyclic acid anhydride reacts with the cyclic ether.
° C, preferably 50 to 150 ° C, more preferably 10 ° C.
0-150 ° C. During the reaction, the pressure in the reaction vessel varies depending on the reaction temperature, the presence or absence of a solvent, and the type of solvent.However, the increase in unreacted cyclic ether due to the increase in pressure due to the sequential addition of cyclic ether increases the polyether content in the reaction product. It is not preferable because the ether component is increased. Thus, pressure in the reaction vessel is preferably normal pressure ~50kgf / cm ^2, the addition of cyclic ethers such more preferably a normal pressure ~15kgf / cm ^2.

The cyclic ether is added successively by adding 3 to 9 cyclic ethers per hour to 100 parts by weight of the cyclic acid anhydride.
The amount is preferably 0 parts by weight, more preferably 5 to 50 parts by weight.

If the addition rate of the cyclic ether is lower than the lower limit of 3 parts by weight, the reaction is prolonged and the productivity is lowered, which is not industrially preferable. On the other hand, if it is higher than the upper limit of 90 parts by weight, the polyether component in the reaction product increases and only a polyester having a low melting point can be obtained.

The term "sequential addition of the cyclic ether" means that the cyclic ether is not added all at once, and it may be either a method of dropping continuously or a method of intermittent addition in multiple stages. It is preferable to add continuously so that the amount of addition does not largely change over time.

In the present invention, the reaction ratio of the cyclic acid anhydride and the cyclic ether is 40/60 to 6 in a molar ratio of these.
The ratio is preferably 0/40. In view of the fact that the residual cyclic acid anhydride and the terminal carboxyl group of the polyester reduce the physical properties of the polyester, the ratio of 40/60 to 49/49 is added in order to add the cyclic ether in excess. / 5
More preferably, the ratio is 1. By doing so, less than 50% of the terminal carboxyl groups of the polyester become carboxyl groups, and heat resistance is improved. If the ratio is out of the range, the unreacted monomer may increase and the yield may decrease. In the present invention, it is preferable that after the sequential addition of a predetermined amount of the cyclic ether determined in consideration of the above molar ratio, polymerization is continued at the reaction temperature to ripen. The polyester formed from the polymerization system after the aging reaction may be separated.

Next, the step of further polymerizing (condensing) the polymer obtained by the ring-opening polymerization of the method (ii) will be described.

The reaction conditions in the step of further polymerizing (condensing) the polymer obtained by the ring-opening polymerization in the method (ii) are as follows:
Reaction temperature 180-280 ° C, preferably 230-270
° C, degree of vacuum 0.5 mmHg or more, preferably 1.0 mm
Hg or more, more preferably 1.0 to 3.0 mmHg. When the reaction temperature is lower than this range, the reaction time becomes extremely long, and when the reaction temperature is higher than this range, it is industrially disadvantageous because of significant coloration and a large amount of volatile components. When the degree of pressure reduction is 0.5 mmHg or less, that is, when a high vacuum is applied, a large amount of by-products and low molecular weight compounds are generated by depolymerization. Reduction of the degree of decompression due to generation of these volatiles,
The reaction time becomes extremely long or does not reach a predetermined molecular weight due to a decrease in the performance of a vacuum pump or the like.
Further, the yield is remarkably reduced due to generation of volatile components, and even if recovered, these volatile components are not used, and thus become a serious economic problem. Decompression degree is 3.0mmH
When it is lower than g, the reaction time becomes extremely long, which is industrially disadvantageous.

In the method of (ii), in which the cyclic acid anhydride and the cyclic ether are subjected to ring-opening polymerization and then polycondensed, the generated volatile components can be suppressed to a small amount, and water and the like are not generated, and the method is relatively short. It is preferable because it can be produced industrially efficiently in a short time.

The aliphatic polyester obtained by the method (i) or (ii) may be further reacted with various chain extenders to increase the molecular weight.

Examples of the chain extender include isocyanates, epoxies, aziridines, oxazolines, polyvalent metal compounds, polyfunctional acid anhydrides, phosphoric esters, phosphites, and the like. You may.

Although the isocyanate compound is not particularly limited, it is a compound having two or more isocyanate groups in one molecule, for example, tolylene diisocyanate (“T
DI), 4,4'-diphenylmethane diisocyanate (also referred to as "MDI"), hexamethylene diisocyanate, xylylene diisocyanate, meta-xylylene diisocyanate, 1,5-naphthalenedi isocyanate, hydrogen Diisocyanate compounds such as diphenylmethane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, and isophorone diisocyanate; buret polyisocyanate compounds such as Sumidur N (manufactured by Sumitomo Bayer Urethane Co.); IL, HL (manufactured by Bayer AG), Coronate EH (Nippon Polyurethane Industry Co., Ltd.)
Polyisocyanate compound having an isocyanurate ring; adduct polyisocyanate compound such as Sumidur L (manufactured by Sumitomo Bayer Urethane Co., Ltd.); adduct polyisocyanate compound such as Coronate HL (manufactured by Nippon Polyurethane Co., Ltd.) And the like. These can be used alone or in combination of two or more. Further, a block isocyanate may be used.

The reaction ratio between the polyester and the isocyanate compound is not particularly limited. For example, the ratio (NCO / OH (molar ratio)) between the isocyanate group of the isocyanate compound and the hydroxyl group of the polyester is 0.1.
It is preferably from 5 to 3.0, and more preferably from 0.8 to 1.5.

In order to accelerate the urethanization reaction between the polyester and the isocyanate compound, a known catalyst such as an organotin compound or a tertiary amine may be used as needed.

The epoxy compound is not particularly limited, but has at least two epoxy groups in the molecule. Examples thereof include (poly) ethylene glycol diglycidyl ether, (poly) propylene glycol diglycidyl ether, and polytetramethylene. Glycol diglycidyl ether, resorcin diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, adipic acid diglycidyl ester, o-phthalic acid diglycidyl ester,
Terephthalic acid diglycidyl ester, hydroquinone diglycidyl ether, bisphenol S diglycidyl ether, glycerol diglycidyl ether, sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, Triglycidyl tris (2-hydroxyethyl) isocyanurate, glycerol triglycidyl ether, trimethylolpropane polyglycidyl ether, and the like.

The reaction with the epoxy compound can be carried out by first subjecting the cyclic acid anhydride and the cyclic ether to ring-opening polymerization and reacting the resulting polyester with the epoxy compound, or by simultaneously opening the cyclic acid anhydride, the cyclic ether and the epoxy compound. A reaction method or a method in which a cyclic acid anhydride, a cyclic ether and an epoxy compound are simultaneously subjected to a ring opening reaction and further reacted with the epoxy compound.

In order to accelerate the reaction between the polyester and the epoxy compound, a tertiary amine,
Known catalysts such as quaternary ammonium salts and imidazole compounds can be used freely.

The aziridine compound is not particularly limited. For example, 2,2'-bishydroxymethylbutanol-tris [3- (1-aziridinyl) propionate], ethylene glycol-bis [3- (1-aziridinyl) propionate] , Polyethylene glycol-bis [3- (1-aziridinyl) propionate], propylene glycol-bis [3- (1-aziridinyl) propionate], polypropylene glycol-bis [3
-(1-aziridinyl) propionate], tetramethylene glycol-bis [3- (1-aziridinyl) propionate], polytetramethylene glycol-bis [3- (1-aziridinyl) propionate], N,
N'-tetramethylenebisethylene urea, N, N'-pentamethylene bisethylene urea, N, N'-hexamethylene bisethylene urea, N, N'-heptamethylene bisethylene urea, N, N'-octamethylene bis Ethylene urea, N, N'-phenylenebisethylene urea, N,
N'-toluylene bisethylene urea, N, N'-diphenyl-4,4'-bisethylene urea, 3,3'-dimethyldiphenyl 4,4'-bisethylene urea, 3,3'-
Dimethoxydiphenyl 4,4'-bisethylene urea, diphenylmethane P, P-bisethylene urea and the like can be mentioned. One or more of these can be used.

The amount of the aziridine compound used is from 0.001 to 10% by weight, more preferably from 0.01 to 5% by weight, based on the polyester.

The oxazoline compound is not particularly restricted but includes, for example, 2-oxazoline, 2-methyl-2-oxazoline, 2-ethyl-2-oxazoline, 2-isopropyl-2-oxazoline, 2-butyl-2-oxazoline , 2-phenyl-2-oxazoline, 2,2'-
Bis- (2-oxazoline), 2,2'-methylene-bis- (2-oxazoline), 2,2'-ethylene-bis- (2-oxazoline), 2,2'-trimethylene-bis- (2- Oxazoline), 2,2'-tetramethylene-bis- (2-oxazoline), 2,2'-hexamethylene-bis- (2-oxazoline), 2,2'-octamethylene-bis- (2-oxazoline) , 2,2'-ethylene-bis- (4,4'-dimethyl-2-oxazoline), 2,2'-p-phenylene-bis- (2-oxazoline), 2,2'-m-phenylene-bis -(2-oxazoline), 2,2'-m-phenylene-bis-
(4,4'-dimethyl-2-oxazoline), bis-
(2-oxazolinylcyclohexane) sulfide, bis- (2-oxazolinyl norbornane) sulfide, and the like. One or more of these can be used. More preferably, 2,2'-m-phenylene-bis- (2-oxazoline), bis- (2-
Oxazolinyl norbornane) sulfide.

The reaction ratio between the polyester and the oxazoline compound is not particularly limited. For example, the ratio between the 2-oxazoline group (Ox) of the oxazoline compound and the carboxyl group (COOH) of the polyester (Ox
/ COOH (molar ratio)) is preferably 0.5 to 10.0, and more preferably 0.8 to 5.0.

In order to promote the reaction between the polyester and the oxazoline compound, a known catalyst such as an amine salt of an acidic compound may be used as needed.

The polyvalent metal compound is not particularly restricted but includes divalent or higher valent organometallic compounds, metal salts and / or metal alkoxides.

Preferred metals of the divalent or higher organometallic compound and / or metal salt include zinc, calcium,
Copper, iron, magnesium, cobalt, barium and the like can be mentioned. More preferably, after neutralization, zinc (II) acetylacetonate, zinc acetate, zinc formate, zinc propionate, zinc carbonate, etc., which can separate and recover the counter anion of the polyvalent metal compound from the reaction system as a volatile component, are mentioned. .

Examples of the metal alkoxide include aluminum isopropoxide, mono-sec-butoxyaluminum diisopropylate, aluminum ethylate, tetraisopropoxytitanium, tetra-n-butoxytitanium,
Examples thereof include tetra (2-ethylhexyloxy) titanium and tetrastearyloxytitanium.

The reaction ratio between the polyester and the polyvalent metal compound is not particularly limited, but in the case of a neutralization reaction between the carboxyl group at the terminal of the polyester and a divalent or higher valent organometallic compound and / or metal salt, for example, Ratio to the carboxyl group of the polyester (metal compound / C
OOH (molar ratio)) is preferably 0.1 to 2.0, more preferably 0.2 to 1.2.

In the case of the reaction between the hydroxyl group at the polyester terminal and the metal alkoxide, for example, the ratio of the metal compound to the hydroxyl group of the polyester (metal compound / OH (molar ratio)) may be 0.1 to 2.0. Preferably, 0.2
It is more preferable that the number is 1.2.

The polyfunctional acid anhydride is not particularly restricted but includes, for example, pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride, butane-1,2,3,4-tetracarboxylic dianhydride, Maleic acid homopolymer,
Maleic anhydride-vinyl acetate copolymer, maleic anhydride-ethylene copolymer, maleic anhydride-isobutylene copolymer, maleic anhydride-isobutylvinyl ether copolymer, maleic anhydride-acrylonitrile copolymer,
And maleic anhydride-styrene copolymer.

The reaction with the polyfunctional anhydride is carried out by first subjecting the cyclic acid anhydride and the cyclic ether to ring-opening polymerization and reacting the resulting polyester with the polyfunctional acid anhydride, or by reacting the cyclic acid anhydride with the cyclic ether. There is a method in which a polyfunctional acid anhydride is simultaneously subjected to a ring-opening reaction, or a method in which a cyclic acid anhydride, a cyclic ether, and a polyfunctional acid anhydride are simultaneously subjected to a ring-opening reaction, and further, a polyfunctional acid anhydride is reacted.

The amount of the polyfunctional acid anhydride is 0.001 to 10% by weight, more preferably 0.01 to 5% by weight, based on the polyester.

The phosphate or phosphite is not particularly limited, but may be a diester or a triester. Examples of the ester group include methyl, ethyl, propyl, butyl, phenyl and 2-ethylhexyl. Methyl, ethyl and phenyl are preferred in consideration of reactivity and economy.

The phosphate or phosphite is used in an amount of 0.001 to 10% by weight based on the polyester.
And more preferably 0.01 to 5% by weight.

The reaction temperature between the chain extender and the polyester is 20.
To 250 ° C, more preferably 100 to 200 ° C.
° C.

The method of reacting the chain extender with the polyester is not particularly limited, and examples thereof include a method in which the polyester is dissolved in an appropriate solvent and reacted with the chain extender, and a method in which the polyester is heated and melted and reacted with the chain extender. No.

In producing the high-molecular-weight aliphatic polyester of the present invention, a known reactor can be used, but a high-viscosity reactor can also be used.

In order for the transesterification reaction to proceed efficiently, it is necessary to easily volatilize the glycol produced during the reaction. That is, the free surface renewability of the contents of the reaction system is enhanced,
It is necessary to secure a wide gas-liquid contact surface (free surface area).
Specifically, in the case of a vertical reactor, when a flask or a reaction vessel equipped with a normal stirring device is used, the surface area with respect to the volume of the contents is increased by reducing the amount of the contents, so that a wide gas-liquid contact surface is obtained. Can be secured. In the case of a reactor equipped with a helical ribbon blade or a spiral deformed baffle, the surface area can be increased more efficiently.

In the horizontal reactor, a horizontal single-shaft or twin-shaft kneader in which stirring shafts connected to deformed blades are arranged side by side can efficiently increase the surface area.

The reactor for high viscosity used in the present invention may be a batch type or a continuous type. As a batch type, for example, an inverted conical ribbon blade type reactor (Mitsubishi Heavy Industries, Ltd.)
), Twisted lattice blade type reactor (Hitachi, Ltd.)
Can be mentioned. For the continuous type, for example, Hitachi Glasses Blade Polymerizer (manufactured by Hitachi, Ltd.), Hitachi Lattice Blade Polymerizer (manufactured by Hitachi, Ltd.), a self-cleaning reactor (manufactured by Mitsubishi Heavy Industries, Ltd.), a horizontal two-axis reactor (Manufactured by Mitsubishi Heavy Industries, Ltd.), KRC Kneader (manufactured by Kurimoto Iron Works), TEX-K (manufactured by Japan Steel Works, Ltd.), and a single shaft or a widely used extruder or devolatilizer for plastics A twin screw extruder and the like can be mentioned.

The high molecular weight aliphatic polyester thus obtained can be applied to ordinary molding methods such as extrusion molding, injection molding, hollow molding, vacuum molding, etc., and various parts, containers, materials, utensils, It can be a molded product such as a film, a sheet, a fiber, and a nonwoven fabric.

Molded Article The molded article of the present invention is a molded article containing the high molecular weight aliphatic polyester.

The molded article of the present invention can be obtained from the high-molecular-weight aliphatic polyester by a usual molding method such as extrusion molding, injection molding, hollow molding, vacuum molding and the like.

As the form of the molded product, various parts, containers,
Materials, devices, films, sheets, fibers, nonwoven fabrics and the like can be mentioned.

[0086]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. The parts in the examples represent parts by weight.

The evaluation method used in the examples is as follows. The results are summarized in Table 1.

(Molecular Weight) The number average molecular weight in terms of polystyrene was measured using a gel permeation chromatograph.

(Melting point) Measured by DSC.

(Biodegradability test) 130 ° C., 150 kg /
cm ² , a film having a thickness of 200 μm was prepared by a compression molding machine under the conditions of 2 minutes, and the obtained film was buried in a planter charged with soil, and sprinkled once a day.
The sample was stored in a thermo-hygrostat at 65 ° C. and a relative humidity of 65%, and the appearance change after 100 days was observed.

The soil used was one collected from Onohara, Minoh-shi and Nishiburi-cho, Suita-shi, and one obtained by mixing humus in a ratio of 3: 1: 3.

The results are described as follows.

(+): Change in appearance was observed.

(-): No change in appearance was observed. (Tensile test) According to ASTM-D882-90 (Method A), the tensile strength at break, tensile modulus and elongation at break were measured at a tensile speed of 1000 mm / min.

Example 1 1,2-hexanediol 2
0.0 part and 33.8 parts of succinic anhydride were put in a screw tube and stirred at a temperature of 80 ° C. for 7 hours. The supernatant of the obtained product was taken and allowed to cool to obtain a white wax-like branched oligomer (1).

Next, in a three-necked flask equipped with a stirrer, a Wiggrew fractionation tube equipped with a trap immersed in dry ice-methanol at the outlet, and a gas inlet tube, 120.08 parts of succinic anhydride and ethylene glycol 76. 63 parts were put and immersed in an oil bath. Raise the temperature of the oil bath,
Slowly flow nitrogen, temperature 185 ° C, normal pressure ~ 1.0mm
Water and excess ethylene glycol generated in 52 hours at a reduced pressure of Hg were distilled off to obtain a polyester (1) having a number average molecular weight of 6,000.

Next, the obtained polyester (1) 1
0.0 part, 1.0 part of the branched oligomer (1) and tetra-
0.0004 parts of n-butyl titanate was added to a separable flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube. After performing nitrogen replacement three times, the trap was immersed in dry ice-methanol in a nitrogen stream. At a temperature of 240 ° C. under a reduced pressure of 1.0 to 1.1 mmHg with a vacuum pump equipped with
The reaction was carried out for 5.0 hours under the conditions described above to obtain a high molecular weight aliphatic polyester (1). Number average molecular weight by GPC measurement is 7
5000, melting point by DSC measurement was 90.6 ° C. The volatile matter attached to the trap and the upper part of the three-necked flask was 4.3% by weight based on the charged polyester.

During the reaction, no clogging of the vacuum line and no reduction in the performance of the vacuum pump were observed.

The obtained high molecular weight aliphatic polyester (1) was molded using a compression molding machine under the conditions of a molding temperature of 130 ° C., a molding pressure of 150 kgf / cm ² , and a molding time of 2 minutes. It was created. This film was punched into a dumbbell and subjected to a tensile test. The results are shown in Table 1.

Example 2 1,2-Propanediol 2
0.0 part and 52.6 parts of succinic anhydride were put into a screw tube and stirred at a temperature of 80 ° C. for 7 hours. The supernatant of the obtained product was collected and allowed to cool to obtain a white wax-like branched oligomer (2).

Next, 10.0 parts of the polyester (1) obtained in Example 1, 1.0 part of the branched oligomer (1) and 0.0004 parts of tetra-n-butyl titanate were added to a thermometer and a stirrer. And a nitrogen-introduced tube, and after purging with nitrogen three times, under a reduced pressure of 1.0 to 1.1 mmHg with a vacuum pump equipped with a trap immersed in dry ice-methanol in a nitrogen stream. The reaction was carried out at a temperature of 240 ° C. for 5.0 hours to obtain a high molecular weight aliphatic polyester (2). The number average molecular weight by GPC measurement was 80000, and the melting point by DSC measurement was 92.1.
° C. The volatile matter attached to the upper portion of the trap and the three-necked flask was 5.0 with respect to the charged polyester.
% By weight.

During the reaction, no clogging of the vacuum line and no reduction in the performance of the vacuum pump were observed.

The obtained high molecular weight aliphatic polyester (2) was molded using a compression molding machine under the conditions of a molding temperature of 130 ° C., a molding pressure of 150 kgf / cm ² , and a molding time of 2 minutes. It was created. This film was punched into a dumbbell and subjected to a tensile test. The results are shown in Table 1.

Example 3 To an autoclave were added 90.0 parts of succinic anhydride, 10.0 parts of octadecyl succinic anhydride and 2.99 parts of zirconyl octylate, and the atmosphere in the autoclave was replaced with nitrogen. Then, the temperature of the autoclave was gradually increased to 130 ° C. with stirring, and while maintaining the pressure in the autoclave at 4.0 to 8.1 kgf / cm ² at the same temperature, 231.26 parts of ethylene oxide was added at 42 parts per hour. Was introduced continuously over 5.5 hours at an addition rate of. After introducing ethylene oxide, a ripening reaction was performed at 130 ° C. for 1.0 hour, and then the system was returned to room temperature to obtain a polyester. G
The number average molecular weight by PC measurement was 28,000, and the melting point by DSC was 91.3 ° C.

The obtained polyester (11.5 parts) was added to a separable flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube. After purging with nitrogen three times, the polyester was immersed in dry ice-methanol in a nitrogen stream. With a vacuum pump equipped with a trap, under a reduced pressure of 1.0 to 1.2 mmHg, at a temperature of 240
The reaction was carried out at a temperature of 3.0 ° C. for 3.0 hours to obtain a high molecular weight aliphatic polyester (3). The number average molecular weight measured by GPC was 75,000, and the melting point measured by DSC was 90.9 ° C. The volatile matter attached to the upper part of the trap and the three-necked flask was 4.2% by weight based on the charged polyester.
Met.

During the reaction, no clogging of the vacuum line and no reduction in the performance of the vacuum pump were observed.

The obtained high molecular weight aliphatic polyester (3) was molded using a compression molding machine under the conditions of a molding temperature of 130 ° C., a molding pressure of 150 kgf / cm ² and a molding time of 2 minutes to obtain a film having a thickness of 200 μm. It was created. This film was punched into a dumbbell and subjected to a tensile test. The results are shown in Table 1.

(Comparative Example 1) 12.0 parts of the polyester (1) obtained in Example 1 was added to a separable flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube, and after purging with nitrogen three times. 1.0-1.2 m with a vacuum pump equipped with a trap immersed in dry ice-methanol in a nitrogen stream.
The reaction was carried out under a reduced pressure of mHg at a temperature of 240 ° C. for 3.0 hours to obtain a comparative polyester (1). The number average molecular weight measured by GPC was 89000, and the melting point measured by DSC was 99.6 ° C. The volatile matter attached to the upper portion of the trap and the three-necked flask was 5.6% by weight based on the charged polyester.

During the reaction, no clogging of the vacuum line and no reduction in the performance of the vacuum pump were observed.

The obtained comparative polyester (1) was molded using a compression molding machine at a molding temperature of 130 ° C. and a molding pressure of 150 kg.
Molding was performed under the conditions of f / cm ² and molding time of 2 minutes to prepare a film having a thickness of 200 μm. This film was punched into a dumbbell and subjected to a tensile test. However, the film was broken immediately after the start of the test, and measurement was impossible.

[0111]

[Table 1]

[0112]

The high molecular weight aliphatic polyester of the present invention is a high molecular weight aliphatic polyester having improved tearability. Furthermore, the high molecular weight aliphatic polyester is excellent in that it has biodegradability, has practical breaking strength, and has few gel-like substances. Therefore, the high molecular weight aliphatic polyester of the present invention can be effectively used for disposable packaging materials, daily necessities and the like.

According to the production method of the present invention, a high-molecular-weight aliphatic polyester having improved tearability and biodegradability can be synthesized in high yield without danger of gelation.

The molded article of the present invention has improved tearability,
Since it has biodegradability, it is useful for disposable packaging materials and daily necessities.

Claims (8)

[Claims] 1. A plastic tensile test (ASTM-D
882-90 (Method A))
A high molecular weight aliphatic polyester having a number average molecular weight of 30,000 to 200,000 having an elongation at break of 10% or more as measured in / min. 2. An aliphatic ester unit (A) having a branched hydrocarbon group (A) in an amount of 1 to 100 mol% and an aliphatic ester unit having a linear hydrocarbon group (B) in an amount of 0 to 99 mol%. A high molecular weight aliphatic polyester having a number average molecular weight of 30,000 to 200,000. 3. An aliphatic dicarboxylic acid component containing an aliphatic dicarboxylic acid having a branched hydrocarbon group and / or an anhydride thereof and a cyclic acid anhydride, and a cyclic ether having a branched hydrocarbon group. 3. The high molecular weight aliphatic polyester according to claim 1, which is obtained by ring-opening polymerization of an aliphatic glycol component. 4. An aliphatic containing an aliphatic carboxylic acid having two carboxyl groups in the molecule and having a branched hydrocarbon group having 2 or more carbon atoms to which the carboxyl group is bonded and / or an anhydride thereof. 2. A reaction between a dicarboxylic acid component and an aliphatic glycol component.
Or the method for producing a high molecular weight aliphatic polyester according to 2 above. 5. An aliphatic dicarboxylic acid component and 2
Aliphatic glycols having two hydroxyl groups and having a branched hydrocarbon group having 2 or more carbon atoms to which the hydroxyl groups are bonded, and / or
3. The method for producing a high molecular weight aliphatic polyester according to claim 1, wherein the reaction is carried out with an aliphatic glycol component containing the epoxide. 6. An aliphatic containing an aliphatic carboxylic acid having two carboxyl groups in the molecule and having a branched hydrocarbon group having 2 or more carbon atoms to which the carboxyl group is bonded and / or an anhydride thereof. A dicarboxylic acid component and an aliphatic glycol component having two hydroxyl groups in a molecule and having a branched hydrocarbon group having 2 or more carbon atoms to which the hydroxyl groups are bonded, and / or an aliphatic glycol component containing an epoxide thereof. And reacting.
A method for producing the high-molecular-weight aliphatic polyester described in the above. 7. The aliphatic dicarboxylic acid component contains a cyclic acid anhydride, and the aliphatic glycol component contains a cyclic ether.
6. The method for producing a high-molecular-weight aliphatic polyester according to any one of 6. 8. A molded article comprising the high-molecular-weight aliphatic polyester according to claim 1 or 2.