JP2000344877A - Lactic acid-based copolymerized polyester showing excellent resistance to bleeding out - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lactic acid-based copolymerized polyester showing excellent resistance to bleeding out, storage stability, satisfactory biodegradability, transparency essential for a packaging material and flexibility sufficient to be molded. SOLUTION: A lactic acid-based copolymerized polyester showing excellent resistance to bleeding out comprise a polyester component (I) comprising a diol component and a dicarboxylic acid component, said polyester containing at least one component selected from a group consisting of a 20 to 45C diol component (A1), a 20 to 45C dicarboxylic acid (B1) and 1,4- cyclohexanedicarboxylic acid component (B2), and a lactic acid component (II), the weight ratio of the polyester component (I) to the lactic acid component (II) being 2/98 to 80/20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has excellent transparency and bleed-out resistance, and has various molding methods such as blow molding, extrusion molding, injection molding, inflation molding, lamination molding, press molding and extrusion foam molding. TECHNICAL FIELD The present invention relates to a biodegradable lactic acid-based copolymer polyester which can be processed at a temperature, and a method for producing the same.

The lactic acid-based copolyester of the present invention is used in a wide variety of fields such as molding resins, packaging materials such as sheets and films, coating resins, ink resins, adhesive resins, lamination to paper, and foamed resin materials. Useful in

[0003] In particular, as sheets for packaging materials,
For example, tray, cup, plate, blister, PTP, etc.
The film is useful as a wrap film, a food packaging bag, other general packaging bags, garbage bags, shopping bags, general standard bags, bags such as heavy bags, and the like.

[0004]

2. Description of the Related Art In recent years, with the development of the petrochemical industry, the shipment volume of plastic products has increased remarkably, and the amount of discarded products has increased accordingly. Furthermore, plastic waste has evolved into a major environmental problem in recent years.

[0005] In the incineration of these wastes, there is a concern about the generation of toxic gases such as dioxin and the global warming due to the large amount of carbon dioxide generated. Problems such as shortage of disposal sites due to the non-decomposability of plastics have surfaced.

[0006] In addition to these dust problems, the safety of the plastic itself has begun to be questioned. After it became clear that tetraalkyltin could affect the reproduction of shellfish in marine paints, research on endocrine disruptors began to draw attention, and suspicion turned to plastic raw materials, additives and the plastic itself. Is now available.

[0007] Bisphenol A, which is a raw material of polycarbonate and epoxy resin, exhibits a pseudo-female hormone action in the human body, and the results of research as an endocrine disrupting substance have been published and have been echoing. Furthermore, phthalic acid diesters widely used as plasticizers for plastics, and polystyrene dimers and trimers contained in polystyrene are suspected as endocrine disrupting substances. Thus, the dangers of conventional plastics are becoming more important than their convenience.

On the other hand, research and development of biodegradable plastics have been conducted as a means for solving the plastic waste problem.
It has been held around the world for many years. However, it is hard to say that biodegradable plastics are spreading as smoothly as initially expected. This is considered to be due to the fact that, in order to treat biodegradable plastics, a separate waste collection system and a composting facility are required, and the performance and cost are inferior to general-purpose plastics.

In particular, in the field of packaging materials, which is considered to be the main use of biodegradable plastics, biodegradable plastics having the same degree of transparency and flexibility as polyethylene are not commercially available, and cannot meet market demands. This is also considered a factor.

[0010] There are few biodegradable plastics having transparency, and only polylactic acid and cellulose acetate are industrialized. Cellulose acetate is difficult to mold and process, and is very hard unless a plasticizer is used, and has a problem of bleeding out of the plasticizer. Further, polylactic acid has high transparency and is easy to mold, but has a drawback of poor impact resistance and flexibility.

In order to improve these disadvantages, a method of blending a plasticizer and a method of imparting flexibility by copolymerization have been studied. However, there are few low-molecular plasticizers having good compatibility with polylactic acid. For example, JP-A-8-027296 uses triethyl acetylcitrate as a plasticizer. In addition, citrate-based plasticizers and lactate-based plasticizers are used in relatively large amounts, but when the amount of plasticizer increases, bleed-out problems occur, as well as lower transparency, lower heat resistance temperature, etc. Problems arise.

As the polymer plasticizer, polyesters such as polycaprolactone and polyethers are often used. In JP-A-8-199052, polyethers are used as a plasticizer for polylactic acid. In JP-A-283557, an aliphatic polyester composed of an aliphatic dicarboxylic acid and an aliphatic diol is used as a plasticizer to form a polylactic acid. We are trying to soften lactic acid-based polymers.

However, in any case, only an amount that slightly improves the impact strength of the polylactic acid can be added, and if an attempt is made to significantly soften the polylactic acid, the heat resistance decreases as in the case of the low-molecular plasticizer described above. Bleed out.

In the copolymerization method, for example, JP-A-6-314
No. 5661, lactones are polymerized in advance, and polylactic acid is softened by copolymerization with a homopolymer.However, all of the obtained copolymers have low melting points and glass transition temperatures, and are opaque due to crystallization. There was a problem of becoming.

US Pat. No. 5,202,413 describes a method of softening polylactide by copolymerizing lactide with polyethylene adipate having a number average molecular weight of 3,400 or polycaprolactone having a number average molecular weight of 2,000.
However, the content of these aliphatic polyesters is
When the amount is more than 30 parts by weight, there is a problem that the transparency of the lactic acid-based copolymer is reduced. Conversely, when the polyester content is reduced to have transparency, the flexibility of the copolymer is reduced, and a film or a sheet is formed. It is unsuitable for molded products requiring tensile elongation and impact strength.

JP-A-1-108226 discloses a method for producing a block copolymer obtained by copolymerizing a polyether polyol having biodegradability and lactide in order to soften polylactic acid, and a copolymer. Films and copolymer fibers are described.

However, in these methods, when the copolymerization amount of the polyol is increased, the polyol is softened, but the molecular weight becomes extremely low. Because the weight average molecular weight of the resulting lactic acid-based copolyester is as low as 10,000 to 50,000,
There was a problem that a polymer having sufficient strength could not be obtained and moldability was poor.

This is considered to be because polyether having a low molecular weight has a large number of terminal hydroxyl groups per unit weight, so that the polylactic acid polymerization active terminal is easily chain-transferred and the number of molecular chains per unit weight is increased. With conventional polymerization techniques, it is not possible to obtain an ultrahigh molecular weight polyether having a weight-average molecular weight of 70,000 to 100,000, so that a polylactic acid copolymer having sufficient strength cannot be obtained by this copolymerization method.

In JP-A-6-306111, a lactic acid copolymer having an aliphatic polyester block is obtained by carrying out ring-opening polymerization of lactide in the presence of a high-molecular-weight aliphatic polyester. This copolymer is
It is softened by the introduction of the aliphatic polyester, thereby eliminating the brittleness of polylactic acid and realizing high transparency. Furthermore,
Depending on the added amount and the component, it is possible to provide a softened material suitable for processing into a film or a sheet without substantially impairing the heat resistance of polylactic acid.

However, many aliphatic polyesters and polylactic acids have low compatibility, and when stored under high temperature and high humidity conditions for a long period of time, copolymers containing a large amount of aliphatic polyester components, cyclic oligomers or polyester components are formed. There was a problem of bleeding out on the surface of the object.
Such a bleed-out phenomenon leads to problems such as stickiness, blocking and opacity during storage and distribution of the product.

The present inventors have further found that a lactic acid-based copolymer polyester having an aliphatic polyester block mainly composed of polyethylene sebacate has a very slow bleed-out phenomenon due to hydrolysis.
No. 1367. Although these have excellent bleed-out resistance, there is a problem in that the flexibility of the obtained lactic acid-based copolymerized polyester is reduced because the aliphatic polyester is crystalline.

[0022]

The problem to be solved by the present invention is to provide excellent bleed-out resistance, excellent storage stability, sufficient biodegradability, and a need for packaging materials. An object of the present invention is to provide a lactic acid-based copolyester having important transparency and flexibility suitable for molding and a process for producing the same.

[0023]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the problems and found that a specific diol component and a dicarboxylic acid component, that is, a diol component having 20 to 45 carbon atoms and a diol component having 20 to 45 carbon atoms. Lactic acid-based polyester obtained by copolymerizing an aliphatic polyester comprising a dicarboxylic acid component and / or a 1,4-cyclohexanedicarboxylic acid component with lactide in the presence of a polymerization catalyst has excellent transparency and bleed resistance. The present invention was found to have out-out properties and was useful for packaging materials and molding materials, and completed the present invention.

That is, the present invention provides a group consisting of (1) a diol (A1) component having 20 to 45 carbon atoms, a dicarboxylic acid (B1) having 20 to 45 carbon atoms, and a 1,4-cyclohexanedicarboxylic acid component (B2). A polyester component (I) comprising a diol component and a dicarboxylic acid component and a lactic acid component (II), containing at least one component selected from the group consisting of: a weight ratio of the polyester component (I) to the lactic acid component (II); A lactic acid-based copolyester excellent in bleed-out resistance, which is 2/98 to 80/20,

(2) The lactic acid-based copolymer polyester according to (1), wherein the diol component (A1) having 20 to 45 carbon atoms is a dimer diol;

(3) a lactic acid-based copolymer polyester according to (1) or (2), wherein the dicarboxylic acid component (B1) having 20 to 45 carbon atoms is a dimer acid; Dicarboxylic acid component (B1)
Is a hydrogenated dimer acid, the lactic acid-based copolymer polyester according to (1) or (2),

(5) The diol component constituting the polyester component (I) includes a diol component (A1) having 20 to 45 carbon atoms and a diol component (A2) having 2 to 12 carbon atoms. The dicarboxylic acid component (B1) having 20 to 45 carbon atoms and / or the 1,4-cyclohexanedicarboxylic acid component (B2) further have 4 to 12 carbon atoms.
And a weight ratio of these components (A1 + B1 + B2) / (A2 + B3), (A1 + B
1) / (A2 + B3) or (A1 + B2) / (A2 + B
3) is 100/0 to 20/80 (1) to (4)
A lactic acid-based copolyester according to any one of

(6) Any of (1) to (5), wherein the polyester component (I) comprising a dicarboxylic acid component and a diol component is a polyester component having a high molecular weight by an acid anhydride component or a polyfunctional isocyanate component. A lactic acid-based copolymerized polyester according to any one of:

(7) Substantially no polymerization catalyst is contained, or the polymerization catalyst is deactivated by a catalyst deactivator (1) to (6)
A lactic acid-based copolymerized polyester in any one of

(8) The method according to any one of (1) to (7), wherein substantially no bleeding appears within 60 days under a storage condition of a temperature of 35 ° C. and a humidity of 80%. A lactic acid-based copolymer polyester with excellent bleed-out resistance,

(9) C20-45 diol (A)
1) a component, a dicarboxylic acid having 20 to 45 carbon atoms (B1);
A polyester comprising a diol component and a dicarboxylic acid component and a lactide containing at least one component selected from the group consisting of a 1,4-cyclohexanedicarboxylic acid component (B2) are reacted with a polyester and a lactide in the presence of a polymerization catalyst. A method for producing a lactic acid-based copolymerized polyester having excellent bleed-out resistance, wherein the lactic acid-based copolymerized polyester is copolymerized at a weight ratio of 2/98 to 80/20;

(10) The production method according to (9), wherein the diol component (A1) having 20 to 45 carbon atoms is a dimer diol; and (11) a dicarboxylic acid component (B1) having 20 to 45 carbon atoms.
Is a dimer acid, the production method according to (9) or (10),

(12) The dicarboxylic acid component (B1) having 20 to 45 carbon atoms is a hydrogenated dimer acid (9) or (1).
And (13) a diol component containing a diol having 20 to 45 carbon atoms (A1) and a diol having 2 to 12 carbon atoms (A2), and a dicarboxylic acid component having 20 to 45 carbon atoms. 45 dicarboxylic acid (B1) and / or 1,4-cyclohexanedicarboxylic acid component (B2) further contain a dicarboxylic acid component (B3) having 4 to 12 carbon atoms, and a weight ratio (A1 + B1 +
(2) / (A2 + B3) is the production method according to any one of (9) to (12), wherein 100/0 to 20/80.

(14) The polyester comprising a dicarboxylic acid component and a diol component is a polyester whose molecular weight has been increased with an acid anhydride or a polyfunctional isocyanate.
(13) The method according to any one of (1),

(15) The method according to any one of (9) to (14), wherein after the copolymerization, the polymerization catalyst is extracted and removed with a solvent, or the polymerization catalyst is deactivated with a catalyst deactivator. Described manufacturing method,

(16) Under the storage condition of 35 ° C. and 80% humidity described in any one of the above (9) to (14), it is confirmed that substantially no bleeding material appears within 60 days. And a method for producing a lactic acid-based copolymer polyester having excellent bleed-out resistance.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The constituent components of the lactic acid-based copolymerized polyester of the present invention will be described in order. 20-45 carbon atoms
A typical example of the diol used as the diol component (A1) is dimer diol. Dimer diol is
It is a reduced form of a dicarboxylic acid having 20 to 45 carbon atoms generated by a thermal dimerization reaction of an unsaturated fatty acid having 12 or more carbon atoms.

A specific example of the dimer diol which is easily available is a dimer of an aliphatic unsaturated carboxylic acid having 18 carbon atoms manufactured by Henkel. Specific examples of the diol used as the diol component (A2) having 2 to 12 carbon atoms that can be used in combination with the diol (A1) having 20 to 45 carbon atoms include:
Ethylene glycol, 1,3-propanediol, 1,
4-butanediol, 1,5-pentanediol, 1,
6-hexanediol, 1,7-heptanediol,
1,8-octanediol, 1,9-nonanediol,
1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol,

1,4-cyclohexanedimethanol, propylene glycol, 1,3-butanediol, 1,2
-Butanediol, neopentyl glycol, 3,3-
Diethyl-1,3-propanediol, 3,3-dibutyl-1,3-propanediol, 1,2-butanediol, 1,2-pentanediol, 1,3-pentanediol, 2,3-pentanediol, 2,4-pentanediol, 1,4-pentanediol, 1,2-hexanediol, 1,3-hexanediol,

Diols such as 1,4-hexanediol, 1,5-hexanediol and n-butoxyethylene glycol, dimer diols which are reduced forms of dimer acid, diethylene glycol having ether oxygen, dipropylene glycol and triethylene glycol , Polyethylene glycol, polypropylene glycol, polytetramethylene glycol, xylylene glycol having an aromatic group, phenylethylene glycol and the like.

A dicarboxylic acid component having 20 to 45 carbon atoms (B
1) and 1,4-cyclohexanedicarboxylic acid component (B
A representative example of the dicarboxylic acid having 2 to 45 carbon atoms in 2) is dimer acid. Dimer acid has a carbon number of 20 generated by a thermal dimerization reaction of an unsaturated fatty acid having a carbon number of 12 or more.
~ 45 dicarboxylic acids, the starting materials of which are oleic acid and tall oil fatty acids, which have low toxicity.

Although various reaction mechanisms have been proposed for the production of dimer acid, DIels-Ald
The er cyclization reaction is considered to be the main mechanism, and many have an alicyclic structure in the molecule. There are unsaturated double bonds in the molecule and fatty acids saturated by hydrogenation.

Many commercially available dimer acids contain a small amount of monomeric acid or trimer acid. Both components are non-toxic and dimer acid is approved for use in food packaging materials. In the present invention, either an unsaturated dimer acid or a saturated dimer acid may be used. The purity of the dimer acid used is 9
0% or more, preferably 95% or more.

Specific examples of readily available dimer acids include dimer enpols 1061 and 1062 of aliphatic unsaturated carboxylic acids having 18 carbon atoms manufactured by Henkel, and 1-carbon atoms manufactured by the company.
8 dimer enpol of aliphatic saturated carboxylic acid of 1008
And the like.

The 1,4-cyclohexanedicarboxylic acid as the component (B2) has cis- and trans-isomers, both of which can be used in the present invention and are industrially inexpensive. A mixture of both isomers is preferably used.

The dicarboxylic acid (B1) having 20 to 45 carbon atoms represented by dimer acid and the 1,4-cyclohexanedicarboxylic acid (B2) constituting the carboxylic acid component are used without any particular limitation on the quantitative ratio. Can be.

Specific examples of the dicarboxylic acid of the dicarboxylic acid component (B3) having 4 to 12 carbon atoms used in combination with the carboxylic acid components (B1) and (B2) include adipic acid, pimelic acid, suberic acid, azelaic acid, Sebacic acid, decane dicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid and the like can be mentioned. These polyesters used in the present invention become amorphous solids by a combination of carboxylic acid and diol.

The diol component constituting the polyester component (I) of the lactic acid-based copolymer polyester of the present invention includes:
Diol having 20 to 45 carbon atoms (A1) and 2 to 12 carbon atoms
A diol (A2), and as a dicarboxylic acid component,
A dicarboxylic acid having 20 to 45 carbon atoms (B1) and / or a 1,4-cyclohexanedicarboxylic acid component (B2);
Further, it preferably contains a dicarboxylic acid component (B3) having 4 to 12 carbon atoms.

The weight ratio of these components is (A1 + B1 +
B2) / (A2 + B3), (A1 + B1) / (A2 + B
3) or (A1 + B2) / (A2 + B3) is preferably 100/0 to 20/80. This is because when the sum of the components (A1), (B1), and (B2) is less than 20, the number of days until the start of bleed-out is reduced, that is, the bleed-out resistance is reduced.

The lactide used for producing the lactic acid-based copolymerized polyester, which constitutes the lactic acid component (II) in the lactic acid-based copolymerized polyester of the present invention, is a compound in which two molecules of lactic acid are cyclically dimerized by dehydration-condensation. Monomers having a body include L-lactide composed of two molecules of L-lactic acid, D-lactide composed of two molecules of D-lactic acid, and meso-lactide composed of D-lactic acid and L-lactic acid.

A copolymer containing only L-lactide or D-lactide crystallizes and has a high melting point. In the production of the lactic acid-based copolyester of the present invention, preferable resin characteristics can be realized by combining three kinds of lactides in various ratios depending on the use.

In order for the lactic acid-based copolymer polyester of the present invention to have excellent transparency and high bleed-out resistance, the composition ratio of the polyester component (I) / lactic acid component (II) must be 80/20 by weight. ２2/98, more preferably 50/50５０2/98. To obtain a highly flexible lactic acid-based copolymerized polyester, the composition ratio of the polyester component (I) / lactic acid component (II) must be 8% by weight.
It is preferably 0/20 to 20/80, and more preferably 50/50 to 20/80.

Further, when obtaining a lactic acid-based copolymer polyester having a glass transition temperature of 50 ° C. or higher, the composition ratio of the polyester component (I) / lactic acid component (II) is 40/6 by weight.
It is preferably 0 to 2/98, more preferably 3/98.
0/70 to 2/98.

A lactic acid-based copolymer having a high molecular weight is preferable because it can be molded in a wide temperature range. Specifically, a lactic acid-based copolymer having a weight average molecular weight of 50,000 to 400,000 is preferred. preferable. A lactic acid-based copolyester having this molecular weight range was formed into a sheet, and the storage elastic modulus at room temperature was 0.5 to 3.0 KPa as measured by RSAII manufactured by Rheometrics Co., Ltd.

In order to synthesize such a high molecular weight lactic acid-based copolymerized polyester, it is preferable that the polyester used as a raw material has a sufficiently high molecular weight. Commercially available dimer acid contains a trace amount of trimer acid. A high molecular weight polyester having a weight average molecular weight of 50,000 or more can be obtained by adding a transesterification catalyst after dehydration condensation and reducing the pressure to 0.5 KPa or less.

In the present invention, a polymerization catalyst such as titanium, tin, zinc and zirconium is used in an amount of 10 to 100 with respect to polyester.
By performing transesterification using 0 ppm and further adding 10 to 1000 ppm of an antioxidant such as a phosphite compound, it is possible to reduce coloring which becomes a problem during the transesterification reaction.

When the content of dimer acid is small, the molecular weight is 1
It is difficult to obtain more than 100,000 polyester. Therefore, the reaction temperature is suppressed to 220 ° C. or lower to synthesize a polyester having a weight average molecular weight of 40,000 to 50,000, and a carboxylic acid anhydride or a polyfunctional isocyanate is reacted with the polyester so that the molecular weight of the polyester is 100,000 or more. The molecular weight can be increased.

The acid anhydride used in the present invention is a carboxylic acid anhydride having two or more carboxyl groups in one molecule. Specific examples of the carboxylic anhydride include, for example, succinic anhydride, cyclohexanedicarboxylic anhydride, phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic dianhydride and a mixture thereof.

The polyfunctional isocyanate referred to in the present invention is one having two or more isocyanate groups.
Particularly, those having only an isocyanate group as the type of the functional group are preferable. For the purpose of obtaining a urethane bond-containing polyester having a substantially linear structure, a bifunctional polyester is preferred.

Specific examples of the bifunctional isocyanate include:
For example, hexamethylene diisocyanate, 2,4-tolylene diisocyanate, 2,5-tolylene diisocyanate, toluene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate,
5-naphthylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate,
Or a mixture thereof.

Further, those having three or more polyfunctional isocyanates can be used. In this case, the obtained polymer chains become star-shaped. In order to obtain such a compound, a compound obtained by modifying a polyhydric alcohol with a bifunctional isocyanate, such as a compound obtained by modifying pentaerythritol with a bifunctional isocyanate, may be used.

As the polyfunctional isocyanate used in the present invention, several kinds of polyfunctional isocyanates can be used in combination.
When used in combination with a functional isocyanate, it can be reacted and gelled without gelling.

The reaction between the polyester and the carboxylic anhydride or the polyfunctional isocyanate is performed by mixing the reaction product immediately after the completion of the polymerization reaction of the polyester with the diol and the dicarboxylic acid with the carboxylic anhydride or the polyfunctional isocyanate. A method of stirring and reacting in a molten state, or a method of re-adding to a polyester obtained by polymerization and melt-mixing may be used.

Particularly preferred is a method in which both the polyester and the carboxylic acid anhydride or the polyfunctional isocyanate are dissolved in a cosolvent and reacted by heating. This makes it possible to disperse and bond the carboxylic anhydride component or the polyfunctional isocyanate component in the polyester very uniformly.

The temperature at which a polyester is mixed with a carboxylic anhydride or a polyfunctional isocyanate is usually 70 ° C.
C. to 220C, preferably 100C to 190C.
In the reaction of polyfunctional isocyanate, N, N-
It is preferable to use an ester polymerization catalyst such as dimethylaniline, tin octoate, dibutyltin dilaurate, tetraisopropyl titanate, or a urethane catalyst.

The above carboxylic anhydrides and polyfunctional isocyanates can be used as a mixture if necessary.
The amount of these used is preferably 0.01% by weight to 5% by weight of the polyester, more preferably 0.1% by weight.
１1% by weight.

Next, the manufacturing method will be described in order. The two diols and dicarboxylic acid are reacted at a molar ratio of 1.2 to 1.5: 1 under a nitrogen atmosphere to 130 ° C. to 220 ° C. for 5 hours per hour.
Water is distilled off by stirring while gradually increasing the temperature at a rate of 10 ° C. After reacting for 6 to 12 hours, excess glycol is distilled off while gradually increasing the degree of vacuum at 10 to 0.1 KPa.

After reducing the pressure for 2 to 3 hours, the polymerization catalyst and the antioxidant were added and the pressure was reduced to 0.5 KPa or less.
When the reaction is carried out at 4 ° C. for 4 to 12 hours, a highly viscous polyester is obtained. At 180C to 210C, a carboxylic anhydride or a polyfunctional isocyanate is added to the polyester,
In the case of carboxylic anhydride, the reaction is carried out at normal pressure for 3 hours while reducing the pressure at 0.5 to 0.1 KPa, and in the case of isocyanate, a high molecular weight polyester is obtained. When oxygen enters the reaction system, it causes coloring and decomposition. Therefore, when releasing the reduced pressure such as addition of a catalyst, it is preferable to sufficiently perform the replacement with an inert gas such as nitrogen.

The reaction temperature is preferably 200 ° C. or less, and more preferably 180 ° C. or less, in terms of preventing coloring and decomposition of lactide.
The reaction is preferably performed in an atmosphere of an inert gas such as nitrogen and argon. In addition, since the presence of water in the reaction system is not preferable, the polyester used must be sufficiently dried.

Next, the method of copolymerization will be described. Polyester and lactide are mixed with 15 to 30 parts by weight of toluene based on the total weight thereof, and a ring-opening polymerization catalyst such as tin octoate is mixed at 140 to 180 ° C under a nitrogen atmosphere with respect to the total weight of polyester and lactide. 5
0 to 2000 ppm is added.

If the polymerization catalyst used for producing the lactic acid-based polyester remains in the lactic acid-based polyester, the thermal stability is poor,
The lactic acid structural units in the lactic acid-based polyester are regenerated in the form of lactide at the time of heating and molding in the production of the membrane and the composite of the raw material, and the strength and storage stability of the produced membrane are reduced.

In the present invention, the storage stability of the resulting lactic acid-based copolymerized polyester is further improved by extracting and removing the polymerization catalyst with a solvent after the copolymerization or deactivating the polymerization catalyst with a catalyst deactivator. be able to. That is, the polymerization terminal is an alkoxide of tin or titanium, but by washing with an acidic aqueous solution or an acidified protic solvent, the terminal can be hydrolyzed to remove the catalyst.

Specifically, a methanol / hydrochloric acid aqueous solution
Add resin pellets or use methanol /
A method in which the polymer is mixed with a hydrochloric acid solution and washed while precipitating the polymer is used. By such a method, it is possible to simultaneously wash and remove a trace amount of the residual monomer or oligomer.

The polymerization catalyst used in the production of the lactic acid-based polyester can be deactivated by adding the chelating agent and / or the acidic phosphoric acid ester after or after the production of the lactic acid-based polyester. The catalyst deactivator usually adheres to the polymerization catalyst in the lactic acid-based polyester in a chelate-like form and is contained in the lactic acid-based polyester, but may be removed by washing with a solvent or the like.

The amount of the chelating agent and / or acidic phosphate ester used in the present invention varies depending on the type of the catalyst used in the production of the lactic acid-based polyester and the reaction conditions, but the used polymerization catalyst is deactivated. Any amount is acceptable.
Before the polymer is removed from the lactic acid-based polyester polymerization reaction or at the time of kneading, it is usually 0.0
01 to 5 parts by weight, preferably 0.1 to 100 parts by weight are added. These chelating agents and / or acidic phosphates may be added and kneaded to the produced lactic acid-based polyester.

The chelating agent component used in the present invention is not particularly limited, but specific examples thereof include ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetate, oxalic acid, phosphoric acid, pyrophosphoric acid, alizarin, acetylacetone, and diethylenetriaminepentaacetic acid. Triethylenetetramine hexaacetic acid, catechol, 4-t-butylcatechol, L (+)-tartaric acid, DL-tartaric acid, glycine, chromotropic acid, benzoylacetone, citric acid, gallic acid, dimercaptopropanol, triethanolamine, Examples include cyclohexanediaminetetraacetic acid, ditoluoyltartaric acid, and dibenzoyltartaric acid.

The acidic phosphoric acid ester used in the present invention forms a complex with the metal ion of the catalyst contained in the hydroxycarboxylic acid-based polyester, loses the catalytic activity, and has the effect of suppressing the cleavage of the polymer chain. Is shown. The acidic phosphates refer to acidic phosphates, phosphonates, alkylphosphonic acids, and the like, and mixtures thereof.

The acidic phosphoric esters used in the present invention include acidic phosphoric esters, phosphonic esters, alkylphosphonic acids and the like, and mixtures thereof.
Specifically, examples of acidic phosphate esters include monomethyl phosphate, dimethyl phosphate, monoethyl phosphate, diethyl phosphate, monopropyl phosphate, dipropyl phosphate, monoisopropyl phosphate, diisopropyl phosphate, monobutyl phosphate, Dibutyl phosphate, monopentyl phosphate, dipentyl phosphate, monohexyl phosphate, dihexyl phosphate, monooctyl phosphate, dioctyl phosphate, mono-2-ethylhexyl phosphate, di-2-ethylhexyl phosphate,
Monodecyl phosphate,

Didecyl phosphate, monoisodecyl phosphate,
Diisodecyl phosphate, monoundecyl phosphate, diundecyl phosphate, monododecyl phosphate, didodecyl phosphate,
Monotetradecyl phosphate, ditetradecyl phosphate, monohexadecyl phosphate, dihexadecyl phosphate, monooctadecyl phosphate, dioctadecyl phosphate, monophenyl phosphate, diphenyl phosphate, monobenzyl phosphate, dibenzyl phosphate, etc.

Examples of the phosphonate include monomethyl phosphonate, monoethyl phosphonate, monopropyl phosphonate, monoisopropyl phosphonate, monobutyl phosphonate, monopentyl phosphonate, monohexyl phosphonate, monooctyl phosphonate, monoethylhexyl phosphonate, Monodecyl phosphonate, monoisodecyl phosphonate, monoundecyl phosphonate, monododecyl phosphonate, monotetradecyl phosphonate, monohexadecyl phosphonate, monooctadecyl phosphonate, monophenyl phosphonate, monobenzyl phosphonate, etc.

Examples of the alkylphosphonic acid include monomethylphosphonic acid, dimethylphosphonic acid, monoethylphosphonic acid, diethylphosphonic acid, monopropylphosphonic acid, dipropylphosphonic acid, monoisopropylphosphonic acid, diisopropylphosphonic acid, monobutylphosphonic acid, Dibutylphosphonic acid, monopentylphosphonic acid, dipentylphosphonic acid, monohexylphosphonic acid, dihexylphosphonic acid, isooctylphosphonic acid, dioctylphosphonic acid, monoethylhexylphosphonic acid, diethylhexylphosphonic acid, monodecylphosphonic acid, didecylphosphonic acid ,

Monoisodecylphosphonic acid, diisodecylphosphonic acid, monoundecylphosphonic acid, diundecylphosphonic acid, monododecylphosphonic acid, didodecylphosphonic acid, monotetradecylphosphonic acid, ditetradecylphosphonic acid, monohexadecylphosphonic acid Acid, dihexadecylphosphonic acid, monooctadecylphosphonic acid, dioctadecylphosphonic acid, etc., monophenylphosphonic acid,

[0083] Diphenylphosphonic acid, monobenzylphosphonic acid, dibenzylphosphonic acid and the like, and mixtures thereof can be mentioned. The acidic phosphoric acid ester component has good workability due to good solubility in an organic solvent, has excellent reactivity with a lactic acid-based polyester, and has an excellent effect of deactivating a polymerization catalyst.

Lactide is soluble in various solvents, and can be copolymerized using a solvent such as toluene, benzene, xylene, ethylbenzene, chlorobenzene and the like. In the polymerization reaction, it is considered that the copolymerization reaction proceeds by a mechanism in which a polymerization initiator reacts with a terminal hydroxyl group of the polyester and initiates ring-opening polymerization of lactide.

The polymerization conversion was measured by gel permeation chromatography (GPC).
By reacting for 3 hours or more, the conversion of this polymerization reaction reaches 90 to 99%.

The lactic acid-based copolyester of the present invention can be produced by using an ordinary reaction vessel. However, in order to increase the viscosity accompanying the increase in the molecular weight, a copolymer using an ordinary reaction vessel is used. In the polymerization reaction, the stirring efficiency is reduced, causing coloring due to local heating and a reduction in the reaction rate. Therefore, in the present invention,
It is preferable to use a static mixer with uniform stirring and low shear stress.

The reaction can be carried out only with a static mixer. However, a method in which a normal reaction vessel is used in a stage where the viscosity is low and a static mixer is used in the late stage of polymerization before the viscosity is increased is called a polymerization initiator. Are more preferable in that they are uniformly mixed.

The viscoelasticity of the lactic acid-based copolymerized polyester at room temperature becomes softer as the number of carbon atoms in the main chain of the diol constituting the polyester used for the copolymerization increases. Moreover, it becomes softer as the amount of dicarboxylic acid used in combination with dimer acid increases.

The lactic acid-based copolyester having a softening temperature of 30 ° C. or less obtained in the present invention can be rapidly cooled to room temperature using a coolant such as water at the time of molding to have a haze of 250 μm.
% Or less, but when slowly cooled to room temperature, the crystallization of the lactide partly proceeds, the haze of the sheet becomes 10 to 20%, and the transparency is slightly lowered.

The lactic acid-based copolyester of the present invention is used, for example, in a polymer molded product (10 × 10 cm square, 250 μm).
When an accelerated test is performed in a thermo-hygrostat at 35 ° C. and 80% humidity, no bleeding material appears substantially for 60 days or more. It also has excellent hydrolysis resistance, and has a molecular weight retention of 70 to 95% after 30 days under the same conditions. In contrast, in the case of polylactic acid or a polyester copolymer composed of polylactic acid, a dicarboxylic acid having 12 or less carbon atoms, and a diol, the molecular weight retention under the same conditions is 30 to 60%.

Here, the day when the bleed is seen on the surface of the transparent molded product is defined as the bleed start date. When a polyester containing 20 to 45 carbon atoms and not containing a dicarboxylic acid was copolymerized with lactide, a solid or liquid bleed was observed within 60 days in a thermostat at 35 ° C. and 80% humidity.

The lactic acid-based copolymerized polyester obtained in the present invention has good biodegradability, and is subject to decomposition by hydrolysis, biodegradation, etc., even when discarded in the sea. In seawater, the strength as a resin deteriorates in several months, and it can be decomposed without maintaining its external shape. When compost is used, it is biodegraded in a shorter period of time until the original form is not retained. Further, the lactic acid-based copolymerized polyester obtained in the present invention does not emit toxic gas or toxic substance even when incinerated.

The lactic acid-based copolymer polyester of the present invention has excellent bleed-out resistance, excellent storage stability, sufficient biodegradability, and transparency and molding properties important for packaging materials and the like. Because it has flexibility suitable for processing, molding resin, sheet / film material, paint resin, ink resin, toner resin, adhesive resin, lamination to paper, foam resin material, etc., especially packaging material, adhesive Useful as an agent.

Examples of packaging materials include trays, cups, dishes, blisters and the like as sheets, and wrap films, food packaging, and other general packaging, garbage bags, shopping bags, general standard bags, heavy bags and the like as films. Useful for bags and the like.

It is also useful as a blow molded product for other uses, for example, shampoo bottles, cosmetic bottles, beverage bottles, oil containers, etc., and as sanitary products, disposable diapers, sanitary products, and medical devices. As artificial kidneys, sutures, etc., and as agricultural materials, germinated sheets, seed strings,
It is useful for agricultural multi-films, coating agents for slow-release pesticides and fertilizers, bird nets, curing sheets, seedling pots and the like.

Also, fishing materials include fishing nets, seaweed cultivation nets, fishing line, hull bottom paint, etc., and injection molded products include:
Golf tee, cotton swab core, candy stick, brush,
It is useful for toothbrushes, syringes, dishes, cups, combs, razor handles, tape cassettes, disposable spoons and forks, and stationery such as ballpoint pens.

Further, as a lamination product on paper,
Tray, cup, plate, megaphone, etc., binding tape, prepayment card, balloon, pantyhose, hair cap, sponge, cellophane tape, umbrella,
Examples include synthetic feathers, plastic gloves, hair caps, ropes, nonwoven fabrics, tubes, foam trays, foam cushioning materials, cushioning materials, packing materials, and cigarette filters.

[0098]

The present invention will be described more specifically with reference to the following examples and comparative examples. (Reference Example 1) (Synthesis of Polyester A-1) In a 50 L reaction tank equipped with a stirrer, a rectifier, and a gas introduction tube,
Henkel's Empole 1061 (EM1061)
Molar equivalents and 1.4 molar equivalents of ethylene glycol (E
G), and from 150 ° C. to 7 ° C. per hour under a nitrogen stream
The mixture was heated and stirred while the temperature was gradually increased. The temperature was raised to 220 ° C. while distilling off the generated water. After 2 hours, 70 ppm of titanium tetraisopropoxide was added as a transesterification catalyst, and the mixture was stirred under reduced pressure to 0.1 KPa for 6 hours.

As a result, the viscous polyester (A-
No. 1. ) Got. The number average molecular weight of this polymer was 70,000 by gel permeation chromatography (hereinafter abbreviated as GPC) in terms of polystyrene, and the weight average molecular weight was 160,000.

(Reference Example 2) (Synthesis of Polyester A-2) In a 50 L reaction tank equipped with a stirrer, a rectifier, and a gas introduction tube,
Henkel Enpole 1062 (EM1062)
Molar equivalents and 1.4 molar equivalents of ethylene glycol (E
G), and from 150 ° C. to 7 ° C. per hour under a nitrogen stream
The mixture was heated and stirred while being heated. The temperature was raised to 220 ° C. while distilling off generated water, and after 2 hours, 70 ppm of titanium tetrabutoxide was added as a transesterification catalyst,
The pressure was reduced to 0.1 KPa, and the mixture was stirred for 6 hours.

As a result, the viscous polyester (A-
No. 2. ) Got. As a result of measurement by GPC, the polymer had a number average molecular weight of 40,000 and a weight average molecular weight of 110,000.

(Reference Example 3) (Synthesis of Polyester A-3) In a 50 L reaction tank equipped with a stirrer, a rectifier, and a gas inlet tube,
Henkel Enpole 1008 (EM1008)
Molar equivalents and 1.4 molar equivalents of ethylene glycol (E
G), and from 150 ° C. to 7 ° C. per hour under a nitrogen stream
The mixture was heated and stirred while being heated. The temperature was raised to 220 ° C. while distilling off generated water, and after 2 hours, 70 ppm of tin octoate was added as a transesterification catalyst, and 0.1 K
The pressure was reduced to Pa and the mixture was stirred for 6 hours.

As a result, the viscous polyester (A-
No. 3. ) Got. As a result of measurement by GPC, the polymer had a number average molecular weight of 47,000 and a weight average molecular weight of 100,000.

(Reference Example 4) (Synthesis of Polyester A-4) In a 50 L reaction tank equipped with a stirrer, a rectifier, and a gas introduction tube,
66 parts by weight of EM1061 manufactured by Henkel, 34 parts by weight of adipic acid (AA), and 1.4 molar equivalents of ethylene glycol (EG) based on the molar equivalent of dicarboxylic acid were charged, and the mixture was heated at 150 ° C. for 1 hour under a nitrogen stream. The mixture was heated and stirred while the temperature was increased by 7 ° C. 22 while distilling off the generated water
The temperature was raised to 0 ° C., and after 2 hours, 50 ppm of titanium oxyacetylacetonate was added as a transesterification catalyst,
The pressure was reduced to 0.1 KPa, and the mixture was stirred for 6 hours.

As a result, the viscous polyester (A-
No. 4. ) Got. As a result of measurement by GPC, this polymer had a number average molecular weight of 32,000 and a weight average molecular weight of 78,000.

(Reference Example 5) (Synthesis of Polyester A-5) A 10 L reaction tank equipped with a stirrer, a rectifier, and a gas inlet tube was placed in a 10 L reactor.
66 parts by weight of EM1061 manufactured by Henkel succinic acid (S
uA), 34 parts by weight, and 0.9 molar equivalent of ethylene glycol (EG) with respect to the molar equivalent of dicarboxylic acid;
5 molar equivalents of 1,6-hexanediol (1,6HD)
And heated and stirred in a nitrogen stream while increasing the temperature from 150 ° C. by 7 ° C. in one hour.

The temperature was raised to 220 ° C. while distilling off generated water, and after 2 hours, 50 ppm of tributyltin oxide was added as a transesterification catalyst, and the mixture was stirred under reduced pressure to 0.1 KPa for 6 hours. As a result, a viscous polyester (referred to as A-5) was obtained. When the composition ratio was confirmed by NMR, the diol component contained 5% EG: 1,6HD.
0:50. As a result of measurement by GPC, this polymer had a number average molecular weight of 30,000 and a weight average molecular weight of 7
It was 5,000.

Reference Example 6 (Synthesis of Polyester A-6) A 500 mL flask equipped with a stirrer, a rectifier, and a gas inlet tube was charged with 60 parts by weight of 1,4-cyclohexanedicarboxylic acid manufactured by Eastman Chemical Company. Adipic acid (AA)
0 parts by weight and 0.9 molar equivalents of ethylene glycol (EG) and 0.55 molar equivalents of neopentyl glycol (NPG) with respect to the molar equivalents of dicarboxylic acid were charged under a nitrogen stream at 150 ° C. for 10 hours per hour. The mixture was heated and stirred while the temperature was increased by ° C.

The temperature was raised to 220 ° C. while distilling off generated water, and after 2 hours, zinc acetate was added as a transesterification catalyst in 8 hours.
0 ppm was added, the pressure was reduced to 0.1 KPa, and the mixture was stirred for 6 hours. As a result, a viscous polyester (referred to as A-6) was obtained. When the composition ratio was confirmed by NMR,
The diol component had an EG: NPG ratio of 50:50. G
As a result of measurement by PC, the number average molecular weight of this polymer was 3
The weight average molecular weight was 7,000.

Reference Example 7 (Synthesis of Polyester A-7) In a 200 mL flask equipped with a stirrer, a rectifier, and a gas inlet tube, 30 parts by weight of EM1061 manufactured by Henkel and 70 parts by weight of adipic acid (AA). 0.9 mole equivalent of ethylene glycol (EG) and 0.55 mole equivalent of 1,6-hexanediol (1,6
HD), and the temperature is increased from 150 ° C to 1 hour in a nitrogen stream.
The mixture was heated and stirred while increasing the temperature by 0 ° C.

The temperature was raised to 220 ° C. while distilling off the generated water, and after 2 hours, zinc acetate was added as a transesterification catalyst in 8 hours.
0 ppm was added, the pressure was reduced to 0.1 KPa, and the mixture was stirred for 6 hours to obtain a viscous aliphatic polyester. To this was added 0.3 parts by weight of pyromellitic dianhydride (PMDA), and the mixture was stirred at 210 ° C. and 0.1 KPa under reduced pressure. As a result, a high molecular weight polyester (referred to as A-7) was obtained. As a result of measurement by GPC, this polymer had a number average molecular weight of 33,000 and a weight average molecular weight of 80,000.

Reference Example 8 (Synthesis of Polyester A-8) In a 50 L reaction tank equipped with a stirrer, a rectifier, and a gas introduction tube,
60 parts by weight of 1,4-cyclohexanedicarboxylic acid manufactured by Eastman Chemical Co., and 40 parts by weight of EM1061 manufactured by Henkel, 0.9 mol equivalent of ethylene glycol (EG) with respect to the molar equivalent of dicarboxylic acid and 0.55 mol A molar equivalent of 1,6-hexanediol (1,6HD) was charged, and the mixture was heated and stirred while raising the temperature from 150 ° C. to 10 ° C. per hour under a nitrogen stream.

The temperature was raised to 220 ° C. while distilling off generated water, and after 2 hours, 60 ppm of tetraisobutyl titanate was added as a transesterification catalyst, and the mixture was stirred under reduced pressure to 0.1 KPa for 8 hours. As a result, a viscous polyester (referred to as A-8) was obtained. When the composition ratio was confirmed by NMR, the diol component contained 5% EG: 1,6HD.
0:50. As a result of measurement by GPC, this polymer had a number average molecular weight of 27,000 and a weight average molecular weight of 4
It was 3,000.

(Reference Example 9) (Synthesis of Polyester A-9) Polyester A-8 synthesized in Reference Example 8 was added to toluene
0% solution, to which 0.1 part by weight of hexamethylene diisocyanate (HM
DI) was added. Further, 0.02 parts by weight of tin octoate was added to the polyester, followed by stirring at 60 ° C. for 1 hour. As a result, the number average molecular weight of this polymer (A-9) increased to 37,000, and the weight average molecular weight increased to 83,000.

(Reference Example 10) (Synthesis of Polyester A-10) In a 50 L reaction tank equipped with a stirrer, a rectifier, and a gas introduction tube,
60 parts by weight of 1,4-cyclohexanedicarboxylic acid, 40 parts by weight of terephthalic acid, 0.9 mole equivalent of ethylene glycol (EG) and 0.55 mole equivalent of Toagosei Chemical Co., Ltd. The dimer diol (DO) manufactured was charged, and heated and stirred while raising the temperature from 150 ° C. to 10 ° C. per hour under a nitrogen stream.

The temperature was raised to 220 ° C. while distilling off the generated water. After 2 hours, 60 ppm of tetraisobutyl titanate was added as a transesterification catalyst, and the pressure was reduced to 0.1 KPa and the mixture was stirred for 8 hours. As a result, a viscous polyester (referred to as A-10) was obtained. When the composition ratio was confirmed by NMR, the diol component contained EG: DA of 50:
It was 50. As a result of measurement by GPC, the number average molecular weight of this polymer was 53,000, and the weight average molecular weight was 27,
000.

(Example 1) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-1) synthesized in Reference Example 1
10 parts by weight, 90 parts by weight of L-lactide, and 15 parts by weight of toluene based on the total amount of lactide and polyester were put into a separable flask and melted at 180 ° C. After the solution becomes homogeneous, tin octoate 200pp
m and stirred at 180 ° C. for 3.5 hours. After the completion of the polymerization, 500 ppm of ethylhexanoic acid phosphate was added.

The resulting lactic acid-based copolymerized polyester was
PC number average molecular weight 170,000, weight average molecular weight 3
It was confirmed that the copolymer was 50,000. The glass transition temperature of this polymer was 61 ° C. by a differential calorimeter (DSC).

(Example 2) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-1) synthesized in Reference Example 1
20 parts by weight, 80 parts by weight of L-lactide, and 15 parts by weight of toluene based on the total amount of lactide and polyester were put in a separable flask and melted at 180 ° C. After the solution becomes homogeneous, tin octoate 200pp
m was added and stirred at 180 ° C. for 4 hours. After the completion of the polymerization, 500 ppm of ethylhexanoic acid phosphate was added.

The obtained lactic acid-based copolymerized polyester was G
Number average molecular weight 110,000 by PC, weight average molecular weight 2
It was confirmed that the copolymer was 80,000. The glass transition temperature of this polymer was 59 ° C. by a differential calorimeter (DSC).

(Example 3) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-1) synthesized in Reference Example 1
30 parts by weight, 70 parts by weight of L-lactide, and 15 parts by weight of toluene based on the total amount of lactide and polyester were put in a separable flask and melted at 180 ° C. After the solution becomes homogeneous, tin octoate 200pp
m and stirred at 180 ° C. for 5 hours.

After the completion of the polymerization, 500 ppm of ethylhexanoic acid phosphate was added. The obtained lactic acid-based copolymerized polyester was confirmed by GPC to be a copolymer having a number average molecular weight of 80,000 and a weight average molecular weight of 21,000. The glass transition temperature of this polymer was 58 ° C. by a differential calorimeter (DSC).

(Example 4) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-1) synthesized in Reference Example 1
30 parts by weight, 67.2 parts by weight of L-lactide, 2.8 parts by weight of D-lactide, and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask and melted at 175 ° C. . After the solution became homogeneous, 500 ppm of zinc octoate was added, and 173 ° C.
For 7 hours. GPC confirmed that the obtained polymer was a copolymer having a number average molecular weight of 85,000 and a weight average molecular weight of 220,000. Glass transition temperature is 5
7 ° C.

(Example 5) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-1) synthesized in Reference Example 1
40 parts by weight, 57.6 parts by weight of L-lactide, and D-
2.4 parts by weight of lactide and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask and melted at 175 ° C. After the solution became homogeneous, 500 ppm of zinc octoate was added, and 175
Stirred at C for 4 hours. The obtained polymer was measured by GPC for a number average molecular weight of 70,000 and a weight average molecular weight of 160,000.
It was confirmed to be a copolymer of The glass transition temperature was 55 ° C.

(Example 6) (Synthesis of lactic acid-based copolymerized polyester) The high-molecular-weight group polyester (A-
2) 30 parts by weight, 67.2 parts by weight of L-lactide,
2.8 parts by weight of D-lactide and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask and melted at 175 ° C.

When the solution becomes homogeneous, tin octoate 5
Then, the mixture was stirred at 180 ° C. for 3 hours. The obtained polymer was confirmed by GPC to be a copolymer having a number average molecular weight of 90,000 and a weight average molecular weight of 210,000. Glass transition temperature was 58 ° C.

(Example 7) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-3) synthesized in Reference Example 3
30 parts by weight, 67.2 parts by weight of L-lactide, 2.8 parts by weight of D-lactide, and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask and melted at 175 ° C. .

When the solution becomes homogeneous, zinc octoate 1
000 ppm was added, and the mixture was stirred at 173 ° C. for 6 hours. After the completion of the polymerization, 500 pp of ethylhexanoic acid phosphate is added.
m was added. The obtained polymer was a copolymer having a number average molecular weight of 80,000 and a weight average molecular weight of 200,000 by GPC, and a glass transition temperature of 57 ° C.

(Example 8) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-4) synthesized in Reference Example 4
30 parts by weight, 67.2 parts by weight of L-lactide, and D-
2.8 parts by weight of lactide and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask and melted at 175 ° C.

When the solution becomes homogeneous, tin octoate 5
After adding 00 ppm, the mixture was stirred at 175 ° C. for 4 hours. The obtained polymer was confirmed by GPC to be a copolymer having a number average molecular weight of 65,000 and a weight average molecular weight of 190,000. Glass transition temperature was 58 ° C.

(Example 9) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-5) synthesized in Reference Example 5
30 parts by weight, 67.2 parts by weight of L-lactide, 2.8 parts by weight of D-lactide, and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask and melted at 175 ° C. .

After the solution became homogeneous, 500 ppm of titanium tetraisopropoxide was added, and the mixture was stirred at 173 ° C. for 6 hours. After the completion of the polymerization, 500 ppm of ethylhexanoic acid phosphate was added. The obtained polymer was measured by GPC for a number average molecular weight of 90,000 and a weight average molecular weight of 220,0.
No. 00 and a glass transition temperature of 59 ° C.

(Example 10) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-6) synthesized in Reference Example 6
50 parts by weight, 49 parts by weight of L-lactide, 1 part by weight of D-lactide, and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask and melted at 175 ° C.

When the solution becomes homogeneous, tin octoate 3
Then, the mixture was stirred at 175 ° C. for 6 hours. After the polymerization is completed, 500 ppm of ethylhexanoic acid phosphate is added.
Was added. The obtained polymer was analyzed by GPC with a number average molecular weight of 4
It was a copolymer having a weight average molecular weight of 100,000 and a glass transition temperature of 52 ° C.

(Example 11) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-7) synthesized in Reference Example 7
30 parts by weight, 68.6 parts by weight of L-lactide, 1.4 parts by weight of D-lactide, and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask and melted at 175 ° C. . After the solution became homogeneous, 200 ppm of tin octoate was added, and 175 ° C.
For 4 hours. After the completion of the polymerization, 500 ppm of ethylhexanoic acid phosphate was added. The obtained polymer was analyzed by GPC with a number average molecular weight of 72,000 and a weight average molecular weight of 1
40,000 copolymer with a glass transition temperature of 49
° C.

(Example 12) (Synthesis of lactic acid-based copolymerized polyester) High-molecular-weight polyester (A-9) synthesized in Reference Example 9
30 parts by weight, 68.6 parts by weight of L-lactide, and D-
1.4 parts by weight of lactide and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask equipped with a reflux condenser and melted at 170 ° C.

After the solution became homogeneous, 400 ppm of tetramethoxystannate was added, and the mixture was stirred at 175 ° C. for 2 hours. Then, the polymer was fed to a static mixer at 165 ° C. at 5 L / hour, and the obtained polymer was added. Pelletized. The obtained polymer was analyzed by GPC with a number average molecular weight of 8
It was a copolymer having a weight average molecular weight of 210,000 and a glass transition temperature of 55 ° C.

(Example 13) (Synthesis of lactic acid-based copolymerized polyester) The high molecular weight polyester (A-1) synthesized in Reference Example 10
0) 30 parts by weight, 68.6 parts by weight of L-lactide,
1.4 parts by weight of D-lactide and 15 parts by weight of toluene based on the total amount of lactide and polyester were placed in a separable flask equipped with a reflux condenser and melted at 170 ° C.

After the solution became homogeneous, 400 ppm of tetramethoxystannate was added, and the mixture was stirred at 175 ° C. for 2 hours. Then, the polymer was supplied to a static mixer at 165 ° C. at 5 L / hour, and the obtained polymer was added. Pelletized. The obtained polymer was analyzed by GPC with a number average molecular weight of 9
It was a copolymer having a weight average molecular weight of 160,000 and a glass transition temperature of 55 ° C.

(Example 13) (Preparation of lactic acid-based copolymerized polyester sheet) The lactic acid-based copolymerized polyester obtained in
The mixture was dried by heating under reduced pressure for 6 hours. 3.3 g of this polymer and a thickness of 250μ penetrating a 10 cm × 10 cm square
m PET sheet with a thickness of 100 μm, and 200 kg / cm ² while heating and melting at 170 ° C.
For 1 minute.

Next, the sheet was taken out with a water-cooled press for 10 minutes and left at room temperature for 24 hours. 1 obtained
When the haze of a sheet having a thickness of 0 cm × 10 cm and a thickness of 250 μm was measured by Haze according to JIS-K-7127, the haze of the sheet was 0.5%.

(Example 14) (Tension test of lactic acid-based copolymerized polyester sheet) A 35 µm film of the lactic acid-based copolymerized polyester obtained in each of Examples and Comparative Examples was subjected to Autograph A manufactured by Shimadzu Corporation.
The sample was placed on a GS-H and tested at a pulling speed of 200 mm / min. As a result, all the films obtained in the examples exhibited an elongation of 100% or more. The measurement results are shown in Tables 4 to 8.

(Example 15) (Bleed-out test of lactic acid-based copolymerized polyester sheet) The lactic acid-based copolymerized polyester sheet obtained in Example 1 was kept at 35 ° C and a humidity of 80% by a constant temperature constant manufactured by Tabaispec. It was left in the wetter PR-2F. As a result of observing the state of the sheet every day, no bleed-out was observed even after one year. A similar test was conducted for other lactic acid-based copolyester sheets, but no bleed was observed for 40 days or more. Tables 4 to 8 show the results of other lactic acid-based copolymerized polyesters.

(Example 16) (Biodegradability test of lactic acid-based copolymerized polyester sheet) An electric composting device kept at 45 ° C by sandwiching the lactic acid-based copolymerized polyester sheets obtained in Examples 1 to 5 with a wire mesh. Left inside. Household garbage was put into the compost, and the mixture was stirred every few hours so as not to be in an anaerobic environment. Thirty days later, when the sheet was taken out, it was almost ragged and remained in its original form. Further, after 60 days, none of the sheets disappeared and could not be confirmed.

(Example 17) (NMR analysis of lactic acid-based copolymerized polyester) As a typical example of the present invention, the lactic acid-based copolymerized polyester obtained in Examples 3, 6 and 7 was treated under reduced pressure at 120 ° C for 6 hours. Time treatment to completely remove 1-2% of residual monomer.
A sample for MR analysis was prepared. 10 mg of each of these was dissolved in 5 mL of heavy chloroform, and NMR and LA3 manufactured by JEOL Ltd.
1H-NMR was measured using 00.

As a result, in each of the samples, only a signal derived from the polyester block and a signal derived from the polylactide were observed, suggesting a block copolymer structure of these lactic acid-based copolymerized polyesters. When the weight ratio of the polyester / polylactide block was calculated from the molar ratio of each block, the weight ratio was almost equal to the weight ratio obtained by subtracting the residual monomer content from the weight ratio of the charged components.

In Examples 3 and 6, EM1061 and EM101, which are the dicarboxylic acid components of the polyester block, were used.
A signal of a carbon-carbon double bond present in 62 was observed. Table 9 shows these NMR signals.

(Comparative Example 1) (Synthesis of lactic acid-based copolymerized polyester) 30 parts by weight of a polyester having a weight average molecular weight of 45,000 synthesized from ethylene glycol and succinic acid (SuA), 68 parts by weight of L-lactide, and D -2 parts by weight of lactide, and 30 parts by weight of toluene based on the total amount of lactide and polyester are put into a separable flask,
Melted at 170 ° C. After the solution became homogeneous, 200 ppm of tin octoate was added, and the mixture was stirred at 170 ° C. for 3.5 hours.

The resulting lactic acid-based copolymerized polyester was
PC number average molecular weight 40,000, weight average molecular weight 7
It was confirmed that the copolymer was 7,000. The glass transition temperature of this polymer was 3 using a differential calorimeter (DSC).
4 ° C.

(Comparative Example 2) (Synthesis of lactic acid-based copolymerized polyester) 30 parts by weight of a polyester having a weight average molecular weight of 35,000 synthesized from 1,6-hexanediol (1,6HD) and adipic acid (AA), 68 parts by weight of L-lactide and 2 parts by weight of D-lactide were put into a separable flask with 15 parts by weight of toluene based on the total amount of lactide and polyester, and melted at 170 ° C. After the solution became homogeneous, 200 ppm of tin octoate was added and 175
Stirred at C for 3.5 hours.

The resulting lactic acid-based copolymerized polyester was
Number average molecular weight 58,000, weight average molecular weight 10 by PC
It was confirmed to be a 000 copolymer. The glass transition temperature of this polymer was measured by a differential calorimeter (DSC).
8 ° C.

(Comparative Example 3) (Synthesis of lactic acid-based copolymerized polyester) 30 parts by weight of a polyester having a weight average molecular weight of 75,000 synthesized from ethylene glycol (EG) and sebacic acid (SeA), and 68 parts by weight of L-lactide And 2 parts by weight of D-lactide were placed in a separable flask with 15 parts by weight of toluene based on the total amount of lactide and polyester, and melted at 170 ° C. After the solution became homogeneous, 200 ppm of tin octoate was added and the mixture was stirred at 175 ° C. for 3.5 hours.

The resulting lactic acid-based copolymerized polyester was
Number average molecular weight 55,000 by PC, weight average molecular weight 11
It was confirmed to be a 000 copolymer. The glass transition temperature of this polymer was measured by a differential calorimeter (DSC).
2 ° C.

[0154]

[Table 1]

[0155]

[Table 2]

[0156]

[Table 3]

[0157]

[Table 4]

[0158]

[Table 5]

[0159]

[Table 6]

[0160]

[Table 7]

[0161]

[Table 8]

[Table 9]

[0162]

[Table 10]

[0163]

The present invention has excellent bleed-out resistance, excellent storage stability, sufficient biodegradability, transparency important for packaging materials, and flexibility suitable for molding. Can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08G63 / 91 C08G63 / 91 F term (Reference) 4J029 AA05 AB01 AB04 AC02 AD01 AD06 AD07 AD10 AE01 AE03 AE06 AE11 AE13 BA01 CA02 CD03 EA05 EH03 GA02 GA05 GA12 GA22 JB232 JC152 KB02 KH01 4J034 BA03 DA01 DB03 DC01 DC07 DC50 DF01 DF15 DF16 DF19 DF20 HA06 HA07 HC03 HC12 HC13 HC17 HC22 HC46 HC52 HC61 HC64 HC71 QB03 QB07 RA08 RA06

Claims (16)

[Claims] 1. A diol (A1) component having 20 to 45 carbon atoms, a dicarboxylic acid (B1) having 20 to 45 carbon atoms, and 1,4.
A polyester component (I) comprising at least one component selected from the group consisting of cyclohexanedicarboxylic acid component (B2) and comprising a diol component and a dicarboxylic acid component, and a lactic acid component (II); ) And lactic acid component (II) in a weight ratio of 2/98 to 8
0/20, a lactic acid-based copolymer polyester having excellent bleed-out resistance. 2. A diol component having 20 to 45 carbon atoms (A)
The lactic acid-based copolymerized polyester according to claim 1, wherein 1) is a dimer diol. 3. The lactic acid-based copolymerized polyester according to claim 1, wherein the dicarboxylic acid component (B1) having 20 to 45 carbon atoms is a dimer acid. 4. The lactic acid-based copolymerized polyester according to claim 1, wherein the dicarboxylic acid component (B1) having 20 to 45 carbon atoms is a hydrogenated dimer acid. 5. A diol component (A) having 20 to 45 carbon atoms as a diol component constituting the polyester component (I).
1) and a diol component (A2) having 2 to 12 carbon atoms, and as a dicarboxylic acid component, a dicarboxylic acid component (B1) having 20 to 45 carbon atoms and / or a 1,4-cyclohexanedicarboxylic acid component (B2). And a dicarboxylic acid component (B3) having 4 to 12 carbon atoms, and the weight ratio of these components (A1 + B1 + B2) / (A2 + B3), (A1 + B
1) / (A2 + B3) or (A1 + B2) / (A2 + B
The lactic acid-based copolymerized polyester according to any one of claims 1 to 4, wherein 3) is 100/0 to 20/80. 6. The polyester component according to claim 1, wherein the polyester component (I) comprising a dicarboxylic acid component and a diol component has a high molecular weight with an acid anhydride component or a polyfunctional isocyanate component. The lactic acid-based copolymer polyester according to 1. 7. The lactic acid-based copolymerized polyester according to claim 1, wherein the polymerization catalyst is substantially free of a polymerization catalyst, or the polymerization catalyst is deactivated by a catalyst deactivator. 8. Under storage conditions of a temperature of 35 ° C. and a humidity of 80%,
The lactic acid-based polyester excellent in bleed-out resistance according to any one of claims 1 to 7, wherein substantially no bleeding material appears within 60 days. 9. A diol (A1) component having 20 to 45 carbon atoms, a dicarboxylic acid (B1) having 20 to 45 carbon atoms, and 1,4.
A polyester comprising a diol component and a dicarboxylic acid component and a lactide containing at least one component selected from the group consisting of a cyclohexanedicarboxylic acid component (B2) and a polyester / lactide having a weight ratio of Copolymerized from 2/98 to 80/20,
A method for producing a lactic acid-based copolymer polyester having excellent bleed-out resistance. 10. A diol component having 20 to 45 carbon atoms (A)
The production method according to claim 9, wherein 1) is a dimer diol. 11. The method according to claim 9, wherein the dicarboxylic acid component (B1) having 20 to 45 carbon atoms is a dimer acid. 12. The process according to claim 9, wherein the dicarboxylic acid component (B1) having 20 to 45 carbon atoms is a hydrogenated dimer acid. 13. A diol component having 20 to 4 carbon atoms.
5 diol (A1) and a diol having 2 to 12 carbon atoms (A
2) wherein the dicarboxylic acid component has 20 to 20 carbon atoms
45 dicarboxylic acid (B1) and / or 1,4-cyclohexanedicarboxylic acid component (B2)
12 dicarboxylic acid components (B3) and a weight ratio (A1
+ B1 + B2) / (A2 + B3) is 100 / 0-20
The method according to any one of claims 9 to 12, wherein the ratio is / 80. 14. The polyester comprising a dicarboxylic acid component and a diol component, wherein the polyester has a high molecular weight with an acid anhydride or a polyfunctional isocyanate.
3. The production method according to any one of 3. 15. The process according to claim 9, wherein after the copolymerization, the polymerization catalyst is extracted and removed with a solvent, or the polymerization catalyst is deactivated with a catalyst deactivator. Method. 16. A bleed resistant material, wherein substantially no bleeding material appears within 60 days under the storage conditions of a temperature of 35 ° C. and a humidity of 80% according to any one of claims 9 to 14. A method for producing a lactic acid-based copolyester excellent in outability.