JP3155198B2 - Polyester film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyester film. More specifically, the present invention relates to a film made of an aliphatic polyester resin composition having an improved crystallization rate.

[0002]

2. Description of the Prior Art Aliphatic polyesters are generally recognized for their biodegradability, and are expected to be used in fibers, molded articles, sheets and films by utilizing their characteristics.

However, the present inventors have been studying the moldability of aliphatic polyesters for a long time.
SC), the half-width of the exothermic peak due to slow cooling crystallization in the measurement by SC was 1 at a cooling rate of 3 ° C./min.
It turned out to be 5 ° C. or higher, indicating that the crystallization was slow and the moldability was poor. That is, it was found that when forming a film by inflation molding or T-die molding, a film was not formed well, and problems such as fusion to a take-up roll, fusion between films, and blocking remained.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide an aliphatic polyester film having excellent moldability and productivity.

[0005]

In view of the above situation, the present inventors have made intensive studies to solve the above problems, and as a result, have found that an aliphatic dicarboxylic acid component having 2 to 6 carbon atoms,
It comprises a high molecular weight aliphatic polyester (A) having a number average molecular weight of 10,000 to 100,000 obtained from 2 to 4 aliphatic glycol components and a crystal nucleating agent (B), and (A) is measured by a differential scanning calorimeter. When the half-width of the exothermic peak based on the slow cooling crystallization of the component is measured at a cooling rate of 3 ° C./min, 100 parts by weight of the component (A) is adjusted so that the half-width is 15 ° C. or less. The above object has been achieved by developing a film comprising a polyester resin composition in which the component (B) is blended in the range of 0.5 to 5 parts by weight .

That is, the polyester film according to the present invention comprises an aliphatic dicarboxylic acid component having 2 to 6 carbon atoms ,
A high molecular weight aliphatic polyester having a number average molecular weight from 10,000 to 100,000 obtained from aliphatic glycol component having 2 to 4 carbon atoms (A), comprises a crystal nucleating agent (B), in differential scanning calorimetry ( A) When the half width of the exothermic peak based on the slow cooling crystallization of the component is measured at a cooling rate of 3 ° C./min, the half width is 15 ° C. or less.
Component (B) is added in an amount of 0.5 to 100 parts by weight of component (A).
It is characterized by comprising a polyester resin composition blended in a range of 5 parts by weight .

The thickness of the film in the present invention is not particularly limited, and includes a film having a thickness generally less than 0.25 mm and a sheet having a thickness of 0.25 mm or more.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The high molecular weight aliphatic polyester (A) used in the present invention has a number average molecular weight of 10,000 to 1
00000, but preferably 25,000 to 8
0000, more preferably 40,000 to 70,000. In order to use the high molecular weight aliphatic polyester (A) as a film, the number average molecular weight must be at least 10,000 or more. If it is lower than this, there is an industrial problem such as brittleness or inability to stretch, and it is possible to react with a chain extender to increase the molecular weight, but the process becomes multi-step or the chain extender used However, this is industrially disadvantageous because it may cause fisheye in the film. In consideration of thermal deterioration and strength, the number average molecular weight of the aliphatic polyester is preferably 25,000 or more, more preferably 40000 or more. On the other hand, if the number average molecular weight is 100,000 or more, the reaction requires a long time, which is industrially disadvantageous. Since the volatile matter generated by decomposition or the like due to the reaction for a long time increases, the number average molecular weight is 100,000 or less, and 8
It is preferably 0000 or less, more preferably 70,000 or less.

The specific method for producing the high-molecular-weight aliphatic polyester (A) used in the present invention is not particularly limited. Generally, the method for obtaining the high-molecular-weight aliphatic polyester includes (i) a polybasic acid (or an ester thereof). (Ii) Polycondensation of hydroxycarboxylic acid (or ester thereof) (iii) Ring-opening polymerization of cyclic acid anhydride and cyclic ether (iv) Ring-opening polymerization of cyclic ester And the like.

The polybasic acid used in the method (i) includes, for example, succinic acid, adipic acid, suberic acid, sebacic acid, azelaic acid, decanedicarboxylic acid, octadecanedicarboxylic acid, dimer acid and esters thereof. Examples of the glycol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, decamethylene glycol and the like. . 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. Among these, the melting point of the obtained polyester, biodegradability, considering the economics,
Aliphatic dicarboxylic acid component having 2 to 6 carbon atoms and 2 to 4 carbon atoms
The combination with an aliphatic glycol component of succinic acid and ethylene glycol and / or succinic acid is preferred.
More preferred is the combination of 4-butanediol. In the production of the high molecular weight aliphatic polyester (A), the total amount of the polybasic acid (or its ester) component and the glycol component may be initially mixed and reacted, or may be added separately as the reaction proceeds. I can't tell. The polycondensation reaction can be carried out by a usual transesterification method or esterification method, or a combination of the two methods. If necessary, the degree of polymerization can be increased by increasing or decreasing the pressure in the reaction vessel. Usually, a small amount of catalyst needs to be used in the transesterification reaction. The catalyst is not particularly limited 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 catalyst is used in an amount of 0.001 to 5 parts by weight, preferably 0.1 part by weight, per 100 parts by weight of the high-molecular-weight aliphatic polyester obtained.
01 to 0.5 parts by weight.

The hydroxycarboxylic acid used in the method (ii) includes, for example, glycolic acid, lactic acid, 3-hydroxypropionic acid, 3-hydroxy-2,2-dimethylpropionic acid, 3-hydroxy-3-methyl-butyric acid , 4-hydroxybutyric acid, 5-hydroxyvaleric acid, 3-
Examples include hydroxybutyric acid, 3-hydroxyvaleric acid, 4-hydroxyvaleric acid, 6-hydroxycaproic acid, citric acid, malic acid and esters thereof. As the polycondensation reaction, there is no problem by using a usual transesterification method or esterification method or a combination of both methods. If necessary, the degree of polymerization can be increased by increasing or decreasing the pressure in the reaction vessel.

The cyclic acid anhydride used in the method (iii) includes, for example, succinic anhydride, maleic anhydride, itaconic anhydride, glutaric anhydride, adipic anhydride, citraconic anhydride and the like. Examples of the cyclic ether include ethylene oxide, propylene oxide, cyclohexene oxide, styrene oxide, epichlorohydrin, allyl glycidyl ether, phenyl glycidyl ether, tetrahydrofuran, oxepane, 1,
3-dioxolan and the like. Of these,
Considering the melting point of the obtained polyester, biodegradability, and economic efficiency, a cyclic acid anhydride containing succinic anhydride as a main component,
A combination with a cyclic ether containing ethylene oxide as a main component is preferred, and a combination of succinic anhydride and ethylene oxide is more preferred. The ring-opening polymerization can be carried out using a known ring-opening polymerization catalyst by a method such as polymerization in a solvent or bulk polymerization.

The cyclic ester used in the method (iv) includes, for example, β-propiolactone, β-methyl-
β-propiolactone, δ-valerolactone, ε-caprolactone, glycolide, lactide and the like.
The ring-opening polymerization can be carried out using a known ring-opening polymerization catalyst by a method such as polymerization in a solvent or bulk polymerization.

Among the methods for obtaining such a high molecular weight aliphatic polyester (A), a method which can be industrially and efficiently produced in a relatively short time includes the method of (iii) ring-opening a cyclic acid anhydride and a cyclic ether. Polymerization is preferred. Hereinafter, the method (iii) by ring-opening polymerization of a cyclic acid anhydride and a cyclic ether will be described in more detail.

It has been known that the cyclic acid anhydride such as succinic anhydride used in the method (iii) 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. 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 cyclic acid anhydride.
The amount is preferably 0 parts by weight, more preferably 5 to 50 parts by weight. If the rate of addition 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 may be either a method of dropping continuously or a method of intermittently adding it 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 from 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 deteriorate the physical properties of the polyester, the ratio of 40/40 is added to excessively add the cyclic ether (D). 60-4
More preferably, the ratio is 9/51.
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.

(I), (ii), (iii), (iv)
If the number average molecular weight of the polyester obtained by any of the above methods is lower than 10,000, it may be further increased in molecular weight by a transesterification reaction, or may be reacted with various chain extenders to increase the number average molecular weight to 10,000 or more. The high molecular weight aliphatic polyester (A) in the present invention
May be used.

Examples of the chain extender include isocyanates, epoxies, aziridines, oxazolines, polyvalent metal compounds, polyfunctional anhydrides, phosphoric esters, phosphites, and the like, or a combination of two or more. 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 of the isocyanate group of the isocyanate compound to the hydroxyl group of the polyester (NCO / OH (molar ratio)) 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 is carried out by first subjecting the cyclic acid anhydride (C) and the cyclic ether (D) to ring-opening polymerization and reacting the resulting polyester with the epoxy compound, or by reacting the cyclic acid anhydride (C) with the epoxy compound. There is a method in which the cyclic ether (D) and the epoxy compound are simultaneously subjected to a ring-opening reaction, or a method in which the cyclic acid anhydride (C), the cyclic ether (D) and the epoxy compound are simultaneously subjected to a ring-opening reaction, and the epoxy compound is further reacted.

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 0.001 to 10% by weight, more preferably 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 (Ox) between the 2-oxazoline group (Ox) of the oxazoline compound and the carboxyl group (COOH) of the polyester
/ COOH (molar ratio)) is preferably 0.5 to 10.0, and more preferably 0.8 to 5.0.

In order to accelerate 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 valent 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. .

As the metal alkoxide, 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. In the case of the neutralization reaction between the carboxyl group at the polyester terminal and the 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 acid anhydride is carried out by first subjecting the cyclic acid anhydride (C) and the cyclic ether (D) to ring-opening polymerization, and then reacting the resulting polyester with the polyfunctional acid anhydride. A method in which the anhydride (C), the cyclic ether (D) and the polyfunctional acid anhydride are simultaneously subjected to a ring opening reaction, or a method in which the cyclic acid anhydride (C) and the cyclic ether (D) and the polyfunctional acid anhydride are simultaneously subjected to a ring opening reaction. And a method of further reacting a polyfunctional acid anhydride.

The amount of the polyfunctional acid anhydride to be used 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 to react with the chain extender. No.

The nucleating agent (B) used in the present invention includes the following from known compounds. Carbon black, calcium carbonate, synthetic silicic acid and silicate, zinc white, high cytoclay, kaolin, basic magnesium carbonate, mica, talc, quartz powder, diatomaceous earth, dolomite powder, titanium oxide, zinc oxide,
Antimony oxide, barium sulfate, calcium sulfate, alumina, calcium silicate, boron nitride, etc .; low molecular weight organic compounds having a metal salt of a carboxyl group, for example, octylic acid, toluic acid, heptanoic acid, pelargonic acid, lauric acid, myristine Metal salts such as acids, palmitic acid, stearic acid, behenic acid, cerotic acid, montanic acid, melicic acid, benzoic acid, p-tert-butylbenzoic acid, terephthalic acid, terephthalic acid monomethyl ester, isophthalic acid, and isophthalic acid monomethyl ester Etc .; high molecular organic compounds having a metal salt of a carboxyl group, for example, carboxyl group-containing polyethylene obtained by oxidation of polyethylene, carboxyl group-containing polypropylene obtained by oxidation of polypropylene, ethylene, propylene, butene Copolymers of olefins such as -1 and acrylic acid or methacrylic acid, copolymers of styrene and acrylic acid or methacrylic acid, copolymers of olefins and maleic anhydride, and copolymers of styrene and maleic anhydride Metal salts such as copolymers and the like; high molecular organic compounds, for example, 3,3-dimethylbutene-1, 3-methylbutene-1, 3-methylpentene-1, 3-methylhexene-
3-position branched α-olefins having 5 or more carbon atoms such as 1,3,5,5-trimethylhexene-1, and polymers of vinylcycloalkanes such as vinylcyclopentane, vinylcyclohexane and vinylnorbornane, polyethylene glycol and polypropylene glycol Polyalkylene glycol, polyglycolic acid, cellulose, cellulose ester, cellulose ether, etc .; phosphoric acid or phosphorous acid and metal salts thereof, for example, diphenyl phosphate, diphenyl phosphite, bis (4-tert-phosphate)
Butylphenyl) sodium, methylene phosphate (2,4
-Tert-butylphenyl) sodium and the like; bis (p
Sorbitol derivatives such as -methylbenzylidene) sorbitol and bis (p-ethylbenzylidene) sorbitol; thioglycolic anhydride, paratoluenesulfonic acid and metal salts thereof.

The amount of the crystal nucleating agent (B) is 0.000 parts by weight based on 100 parts by weight of the high molecular weight aliphatic polyester (A).
It is preferably in the range of 01 to 10 parts by weight, more preferably in the range of 0.5 to 5 parts by weight. 0.0001
If the amount is less than 10 parts by weight, it is difficult to obtain a predetermined effect,
If the amount is more than 0 parts by weight, the effect corresponding to the amount of the compound cannot be expected, and it is not only practical but also uneconomical.

The crystal nucleating agent (B) has an average particle size of 50 μm or less, but preferably has an average particle size of 10 μm or less from the viewpoint of deterioration of the film appearance due to generation of fish eyes.

The polyester resin composition used in the present invention is prepared by dispersing the nucleating agent (B) in the high-molecular-weight aliphatic polyester (A) component by any method and forming a composite. A method of kneading the agent (B) when producing the high molecular weight aliphatic polyester (A), a method of kneading the crystal nucleating agent (B) after producing the high molecular weight aliphatic polyester (A), and the like are applicable. .

The polyester resin composition used in the present invention has a half-width of an exothermic peak in a crystallization temperature range of the high molecular weight aliphatic polyester (A) measured by a cooling crystallization measurement by DSC at a cooling rate of 3 ° C./min. It must be blended so as to be 15 ° C. or less, preferably 10 ° C. or less under the conditions.

This DSC measurement can be performed by a conventional method using a commercially available device such as SSC5200 manufactured by Seiko Denshi Kogyo KK. For example, sample 2 in a nitrogen atmosphere
0 mg is heated above the melting point of the high molecular weight aliphatic polyester (A) and completely melted, and then cooled at a predetermined rate.
This is performed by recording the exothermic peak accompanying crystallization.

The DSC measurement of the high molecular weight aliphatic polyester (A) shows that the exothermic peak based on crystallization is 10 to 200 ° C. at a cooling rate of 3 ° C./min.
Appear in the range. However, this exothermic peak is usually extremely wide, and when the nucleating agent (B) is not added, the half width of the peak is usually about 25 ° C., and even when it is small, it is about 15 ° C. When the cooling rate is further increased, the exothermic peak based on crystallization shifts further to the lower temperature side, while the half-value width of this peak further widens. The high molecular weight aliphatic polyester (A) having a large half width of the exothermic peak based on such slow cooling crystallization has a slow crystallization, and a good molded product cannot be obtained.

On the other hand, in the polyester resin composition used in the present invention, the exothermic peak based on the crystallization in the cooling process of the DSC measurement often shows a high temperature side at a cooling rate of 3 ° C./min. As the temperature shifts, the heat generation peak becomes extremely sharp. The half width of this peak is at least 15 ° C or less, preferably 10 ° C or less, more preferably 8 ° C or less.

The polyester resin composition used in the present invention may contain, if necessary, other components such as pigments, dyes, heat-resistant agents, antioxidants, weathering agents, lubricants, 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 film of the present invention is a film comprising the resin composition, and can be obtained by melt-kneading the resin composition by a usual inflation method or T-die method and extruding. At this time, there is no problem in molding under normal conditions, but in the case of the inflation method, the temperature of the cylinder and die of the extruder is 105 to 105 as the molding temperature.
A film having a thickness of 0.25 mm or less can be obtained at 270 ° C. and a blow ratio of 0.5 to 10. Also, in the case of the T-die method, a film having a thickness of 0.25 mm or less and a sheet having a thickness of 0.25 mm or more are obtained by setting the temperature of the cylinder and the die of the extruder to 105 to 270 ° C. as the molding temperature. Can be.

The film thus obtained usually has a tensile strength at break of 100 kgf / cm ² or more and a tensile elastic modulus of 10 kgf / cm ² or more.
３０30000 kgf / cm ² , preferably 1000 to 15 kgf / cm ²
000 kgf / cm ² . A tensile breaking strength of 100 kgf / cm ² or more is sufficient for practical use as a general film. On the other hand, if it is less than 100 kgf / cm ² , the utility value is considerably reduced, for example, it cannot be used for packaging heavy objects. On the other hand, if the tensile modulus is less than 10 kgf / cm ² , it is difficult to handle due to lack of appropriate stiffness. Tensile modulus is 3000
When it exceeds 0 kgf / cm ² , flexibility is lost and characteristics as a packaging material are lost.

[0058]

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 methods performed in the examples are as follows. Table 1 summarizes the results
It was shown to.

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

(Melting point, crystallization temperature; Tc, half width of exothermic peak; ΔT) DSC (SSC5 manufactured by Seiko Instruments Inc.)
200 type). In a nitrogen atmosphere, 20 mg of the polyester resin composition was heated to a temperature equal to or higher than the melting point of the high-molecular-weight aliphatic polyester (A) to completely melt it, then rapidly cooled to −50 ° C., and then heated at a rate of 6 ° C./min. . The melting point was determined by measuring the endothermic peak at this time. Subsequently, the mixture was cooled at a rate of 3 ° C./min, and the exothermic peak accompanying crystallization was recorded to determine the crystallization temperature and the half width of the exothermic peak.

(Tensile test) ASTM-D882-90
The tensile strength at break, tensile modulus and elongation at break were measured according to (A method).

(Biodegradability test) 130 ° C., 150 kg / c
m ² , a film having a thickness of 200 μm was prepared by a compression molding machine under the conditions of 2 minutes, the obtained film was buried in a planter charged with soil, and water was sprayed once a day at 23 ° C.
It was stored in a thermo-hygrostat at 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.

Example 1 In an autoclave, 500.0 parts of succinic anhydride and 4.90 of zirconyl octylate were added.
Was replaced with nitrogen. Next, the temperature of the autoclave was gradually raised to 130 ° C. with stirring to melt the succinic anhydride, and the pressure inside the autoclave was increased to 4.0 to 8.0 at the same temperature.
While maintaining a pressure of 5 kgf / cm ² , 231.1 parts of ethylene oxide were continuously introduced over a period of 4.0 hours at an addition rate of 58 parts per hour. After the ethylene oxide was introduced, an aging reaction was performed at 130 ° C. for 1.0 hour, and then the system was returned to room temperature to obtain a polymerization product. The operation of dissolving the obtained polymerization product in chloroform and performing precipitation purification in tetrahydrofuran was repeated three times to obtain an aliphatic polyester (1). The yield of this aliphatic polyester (1) was 99.2%. The number average molecular weight measured by GPC was 13,500, and the melting point measured by DSC was 101.2.
° C. The amount of carboxyl groups in the polyester determined by neutralization titration was 0.0501 mmol / g.
From the above measurement results, the ratio of the carboxyl group to the polyester terminal was 33.8%.

70.0 parts of the obtained polymerization product, 0.700 parts of diphenyl phosphite and 2.8 parts of talc were mixed with a self-cleaning twin-screw mixer (S1KRC manufactured by Kurimoto Iron Works Co., Ltd.).
(Reactor, inner diameter 25 mm, L / D = 10.2) in a nitrogen stream under reduced pressure of 0.1 to 0.2 mmHg at 100 rpm
m and a jacket temperature of 240 ° C. for 2.5 hours to obtain a polyester resin composition (1). The number average molecular weight measured by GPC was 52,000. The melting point, the exothermic peak temperature based on crystallization, and the half width of the exothermic peak determined by DSC were 101.6, respectively.
° C, 56.0 ° C, and 4.5 ° C. This DSC chart is shown in FIG.

The obtained polyester resin composition (1) was melted at 110 ° C. and blown to form a film. At the time of molding, there was no fusion to a take-up roll, no blocking between films, and the like.

(Example 2) A polyester resin composition (2) was obtained in the same manner as in Example 1 except that 2.8 parts of talc in Example 1 was changed to 1.4 parts of boron nitride. The number average molecular weight measured by GPC was 52,000. The melting point, the exothermic peak temperature based on the crystallization, and the half width of the exothermic peak were determined by DSC measurement to be 100.8 and 100.8, respectively.
° C, 60.5 ° C, and 7.2 ° C.

The obtained polyester resin composition (2) was melted at 110 ° C. and blown to form a film. At the time of molding, there was no fusion to a take-up roll, no blocking between films, and the like.

Example 3 70.0 parts of the aliphatic polyester (1) obtained in Example 1 was
Shaft mixer (S1KRC reactor manufactured by Kurimoto Iron Works,
(25 mm inner diameter, L / D = 10.2) in a nitrogen stream.
The reaction was carried out under a reduced pressure of 1 to 0.2 mmHg at 100 rpm and a jacket temperature of 240 ° C. for 3.5 hours. The number average molecular weight of the obtained polymerization product measured by GPC was 635.
00. Bis (p-methylbenzylidene) sorbitol (0.6 part) was added to the obtained polymerization product (30.0 parts), and the mixture was melt-mixed with a mixer set at 130 ° C. to obtain a polyester resin composition (3). The melting point, the exothermic peak temperature based on crystallization, and the half width of the exothermic peak were determined by DSC measurement to be 102.8 ° C. and 52.8 ° C., respectively.
It was 4.5 ° C and 7.5 ° C.

The obtained polyester resin composition (3) was melted at 110 ° C. and blown to form a film. At the time of molding, there was no fusion to a take-up roll, no blocking between films, and the like.

Comparative Example 1 The melting point, the exothermic peak temperature based on crystallization, and the half width of the exothermic peak of the aliphatic polyester (1) obtained in Example 1 were determined by DSC. 8 ° C, 51.5 ° C, 16.
3 ° C.

The aliphatic polyester (1) was melted at 110 ° C. and inflation molding was attempted, but no molding was possible.

[0076]

[Table 1]

[0077]

The polyester film of the present invention uses a polyester resin composition having a high crystallization rate and excellent moldability, so that it can be formed well during inflation molding or T-die molding. There are no problems such as fusion to a take-up roll, fusion of films, blocking, etc., and a stable molding can be obtained stably. Further, the polyester film of the present invention is excellent in biodegradability. Therefore, the film of the present invention can be effectively used for disposable packaging materials, daily necessities and the like.

[Brief description of the drawings]

FIG. 1 is a DSC chart of a polyester resin composition (1) in Example 1.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FIB29L 7:00 (72) Inventor Hiroya Kobayashi 5-8 Nishimitabicho, Suita-shi, Osaka Inside Japan Catalyst Function Development Laboratory Co., Ltd. (56) References JP-A-4-314726 (JP, A) JP-A-7-188537 (JP, A) JP-A-8-3432 (JP, A) JP-B-46-116 (JP, B1) Europe Patent application publication 569153 (EP, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08J 5/18 CFD B29C 55/28 C08G 63/12 C08L 67/02

Claims (2)

(57) [Claims] 1. An aliphatic dicarboxylic acid component having 2 to 6 carbon atoms.
When a high molecular weight aliphatic polyester having a number average molecular weight from 10,000 to 100,000 obtained from aliphatic glycol component having 2 to 4 carbon atoms (A), comprises a crystal nucleating agent (B), differential scanning calorimetry In the above, 100 parts by weight of the component (A) is such that the half width of the exothermic peak due to the slow cooling crystallization of the component (A) is measured at a cooling rate of 3 ° C./min so that the half width is 15 ° C. or less. To the component (B) .
A polyester film comprising a polyester resin composition blended in a range of 5 to 5 parts by weight . 2. The high molecular weight aliphatic polyester (A)
Is a cyclic acid anhydride containing succinic anhydride as a main component (C)
The polyester film according to claim 1, which is obtained by ring-opening copolymerization of a cyclic ether (D) containing ethylene oxide as a main component.