JPH1087967A - Liquid crystal polyester resin composition and film thereof - Google Patents

Abstract

(57) Abstract: A liquid crystal polyester resin composition which retains functions such as excellent mechanical properties and heat resistance of a liquid crystal polyester, and improves a specific viscosity behavior upon melting which was a disadvantage of the liquid crystal polyester. In addition, the present invention provides an inexpensive film comprising the composition and having excellent gas barrier properties and thermal stability, and a method for producing the same. A liquid crystal polyester resin composition comprising (A) 56 to 99% by weight of a liquid crystal polyester and (B) 1 to 44% by weight of an acrylic rubber having a functional group capable of reacting with the liquid crystal polyester, and the liquid crystal polyester resin composition A film obtained from a product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal polyester resin composition which can be used for molded articles by injection molding or extrusion molding, and a gas barrier film obtained by forming the composition into a film.

[0002]

2. Description of the Related Art Unlike crystalline polyesters such as polyethylene terephthalate and polybutylene terephthalate, liquid crystal polyesters do not entangle even in a molten state because molecules are rigid, form polydomains having a liquid crystal state, and are formed by low shear. It exhibits a behavior in which molecular chains are remarkably oriented in the flow direction, and is generally called a molten liquid crystal (thermotropic liquid crystal) polymer. Due to this unique behavior, the melt fluidity is extremely excellent, and a thin molded product of about 0.2 to 0.5 mm can be easily obtained, and this molded product has high strength and high rigidity. Have. However, there is a disadvantage that the anisotropy is extremely large. Further, the vibration damping performance and impact resistance are not sufficient, and the molding temperature is high, so that the use thereof has been limited. Another problem is that liquid crystal polyesters are generally expensive.

[0003] The liquid crystal polyester retains excellent heat resistance and mechanical properties, and has improved vibration damping performance and anisotropy of molded products.
Inexpensive liquid crystal polyester resin compositions have been strongly demanded from the market. JP-A-56-115357 discloses a resin composition containing a melt-processable polymer and an anisotropic melt-forming polymer. It is described that the processability of a melt-processable polymer can be improved by adding a water-soluble polymer. For example, an example is given in which a liquid crystal polyester is added to a polyphenylene ether / polystyrene mixture. JP-A-2-97555 describes a resin composition in which various polyarylene oxides are mixed with a liquid crystal polyester for the purpose of improving solder heat resistance. However, in general, a composition comprising a liquid crystal polyester having a high molding temperature and an amorphous polymer such as polyphenylene ether having a lower molding temperature is blended, even if the melt processability of the composition is improved, There has been a problem that the appearance of the molded product is poor due to the thermal decomposition of the compounded resin during the molding process. Further, there is a problem that the heat resistance, mechanical properties, impact resistance, and the like of the composition are insufficient.

Further, JP-A-57-40551 and JP-A-2-102257 disclose compositions comprising a liquid crystal polyester and an aromatic polycarbonate, but they have insufficient heat resistance and mechanical properties. It was not something. U.S. Pat. No. 5,216,073 discloses blends obtained by compounding an epoxidized rubber with a liquid crystal polymer, but their heat resistance and mechanical properties are not sufficient. Also, Japanese Patent Application Laid-Open No. 58-2018
No. 50, JP-A-1-121357, JP-A-1
-193351, EP67272 / A2,
Japanese Patent Application Laid-Open No. 7-304936 describes a composition obtained by blending a thermoplastic resin with a liquid crystalline polymer. However, any of these compositions is required to exhibit sufficient physical properties, particularly, thermal stability of a film. Not reached.

On the other hand, from the viewpoint of film raw materials, liquid crystal polyester is generally called a melt-type liquid crystal (thermotropic liquid crystal) polymer, and is characterized in that molecules are oriented in a molten state by strong intermolecular interaction. Polyester, because of its strong intermolecular interaction, molecular orientation, high strength, well-known for liquid crystal polyester,
Industrialization as a film material having functions such as gas barrier properties in addition to performance such as high elastic modulus and high heat resistance has been expected. However, unlike aromatic polyesters such as polyethylene terephthalate and polybutylene terephthalate, liquid crystal polyesters do not entangle even in the molten state because their molecules are rigid, and their molecular chains are significantly oriented in the flow direction. It exhibits a behavior in which the melt viscosity suddenly decreases, or a behavior in which the melt viscosity sharply decreases due to a rise in temperature, and the melt tension during melting is extremely low. Therefore, it is extremely difficult to maintain the shape in the molten state, and furthermore, it is difficult to balance the vertical and horizontal performance due to the orientation of the molecules, and in extreme cases, it will tear in the direction of molecular orientation, so film forming,
There was a big problem that the utility in fields such as blow molding was poor. Therefore, a film made of a liquid crystal polyester utilizing the function of the liquid crystal polyester has not been put to practical use.

[0006] Such a liquid crystal polyester is disclosed in JP-A-52-109787 and JP-A-58-317.
Japanese Patent No. 187 discloses a laminate in which uniaxially oriented liquid crystal polyester films are laminated in a direction that cancels out the anisotropy of strength. However, the productivity is poor and there is a problem of film peeling. U.S. Pat. Nos. 4,975,312 and WO9015706 disclose a method of canceling the anisotropy of liquid crystal polyester by rotating a ring die.
Japanese Unexamined Patent Publication (Kokai) No.-95930 and JP-A-63-242513 propose a special device in the T-die method.
However, each of these shows a method of relaxing anisotropy due to molecular orientation by a very special molding method,
There is a drawback that the cost is high, the thinning is limited, and the utility is poor.

[0007] Also, Japanese Patent Application Laid-Open No. Sho 62-187033,
JP-A-64-69323, JP-A-2-17801
6, JP-A-2-253919, JP-A-2-253919
JP-A-253920, JP-A-2-253949,
JP-A-2-253950 proposes a multilayer (laminated) sheet and a multilayer (laminated) film of a liquid crystal polyester and a thermoplastic resin. However, peeling occurs due to the interposition of an adhesive layer between the layers, There are problems in that the inherent properties of polyester, such as gas barrier properties and heat resistance, are deteriorated and that it is difficult to produce a thin film.

On the other hand, an attempt has been made to form an inflation film in order to obtain a high-strength liquid crystal polyester film in which the anisotropy of the liquid crystal polymer is reduced. Inflation film formation is a process in which a resin melt-kneaded in an extruder is extruded into a cylindrical melt using a die having an annular slit, a certain amount of air is fed into it, and the resin is expanded to expand the film. A method of making a cylindrical film while cooling the periphery. For example, JP-A-63-173620,
JP-A-3-288623, JP-A-4-4126, JP-A-4-50233 or JP-A-4-4
Japanese Patent No. 9026 and the like describe a method for inflation film formation of a liquid crystal polyester. However, any of these methods is directed to inflation film formation using a special film formation apparatus or liquid crystal polyester having a limited structure. Or inflation film formation under extremely limited conditions, and was not a versatile film formation method.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a liquid crystal polyester which retains the functions such as excellent mechanical properties and heat resistance of the liquid crystal polyester, and improves the peculiar viscosity behavior upon melting, which is a disadvantage of the liquid crystal polyester. It is an object of the present invention to provide a polyester resin composition, a gas barrier property comprising the composition, excellent heat stability, and an inexpensive film, and a method for producing the same.

[0010]

Means for Solving the Problems The present inventors have made intensive studies to solve such a problem and arrived at the present invention. That is, the present invention relates to (A) liquid crystal polyesters 56 to 99.
The present invention relates to a liquid crystal polyester resin composition comprising 1 to 44% by weight of an acrylic rubber having a functional group capable of reacting with a liquid crystal polyester, and a film obtained from the liquid crystal polyester resin composition.

[0011]

Next, the present invention will be described in detail.
The liquid crystal polyester of the component (A) of the liquid crystal polyester resin composition in the present invention is a polyester called a thermotropic liquid crystal polymer. In particular,
(1) a combination of an aromatic dicarboxylic acid, an aromatic diol and an aromatic hydroxycarboxylic acid,
(2) a combination of different kinds of aromatic hydroxycarboxylic acids, (3) a combination of aromatic dicarboxylic acids and a nucleus-substituted aromatic diol, (4) a polyester such as polyethylene terephthalate and an aromatic hydroxycarboxylic acid And an anisotropic melt at a temperature of 400 ° C. or lower. In addition, in place of these aromatic dicarboxylic acids, aromatic diols, and aromatic hydroxycarboxylic acids, ester-forming derivatives thereof may be used. Examples of the repeating structural unit of the liquid crystal polyester include, but are not limited to, the following.

A repeating structural unit derived from an aromatic dicarboxylic acid:

[0013]

A repeating structural unit derived from an aromatic diol:

[0015]

A repeating structural unit derived from an aromatic hydroxycarboxylic acid:

A liquid crystal polyester which is particularly preferred from the balance of heat resistance, mechanical properties and workability is And more preferably contains at least 30 mol% of such repeating structural units. Specifically, combinations of repeating structural units are as shown in the following (I) to (VI).

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

The method for producing the liquid crystal polyesters (I) to (VI) is described in, for example, JP-B-47-47870, JP-B-63-3888, JP-B-63-3891, and JP-B-56-18016. , Tokuho 2-515
No. 23, and the like. Of these, a combination of (I), (II) and (IV) is preferable, and a combination of (I) and (II) is more preferable.

In the field where high heat resistance is required in the liquid crystal polyester resin composition of the present invention, the liquid crystal polyester of the component (A) contains 30 to 80 mol% of the following repeating unit (a '), A liquid crystal polyester in which b ′) is 0 to 10 mol%, the repeating unit (c ′) is 10 to 25 mol%, and the repeating unit (d ′) is 10 to 35 mol% is preferably used.

[0026] (In the formula, Ar is a divalent aromatic group.)

The component (B) of the liquid crystal polyester resin composition of the present invention is an acrylic rubber having a functional group reactive with the liquid crystal polyester of the component (A).

The functional group reactive with the liquid crystal polyester is not particularly limited, but examples thereof include an epoxy group, an oxazonyl group, an amino group and the like, and an epoxy group is preferable. As the functional group having an epoxy group,
A glycidyl group. As the monomer having a glycidyl group, unsaturated glycidyl carboxylate and / or unsaturated glycidyl ether are preferably used.

The compound giving an unsaturated carboxylic acid glycidyl ester unit is represented by the following general formula: It is represented by (In the formula, R is a hydrocarbon group having 2 to 13 carbon atoms having an ethylenically unsaturated bond.)

The compound giving an unsaturated glycidyl ether unit is represented by the general formula: (Wherein, R is a group having 2 to 2 carbon atoms having an ethylenically unsaturated bond)
18 is a hydrocarbon group of, X is -CH ₂ -O- or It is. )

Specifically, examples of the unsaturated glycidyl carboxylate include glycidyl acrylate, glycidyl methacrylate, diglycidyl itaconate, triglycidyl butenetricarboxylate,
Glycidyl p-styrenecarboxylate and the like can be mentioned. As unsaturated glycidyl ethers,
Examples thereof include vinyl glycidyl ether, allyl glycidyl ether, 2-methylallyl glycidyl ether, methacryl glycidyl ether, and styrene-p-glycidyl ether.

The acrylic rubber in the component (B) has the general formula (1) (In the formula, R ¹ represents an alkyl group having 1 to 18 carbon atoms or a cyanoalkyl group.), A general formula (2) (Wherein, R ² is an alkylene group having 1 to 12 carbon atoms;
³ represents an alkyl group having 1 to 12 carbon atoms. ) And general formula (3) (Wherein R ⁴ is a hydrogen atom or a methyl group, R ^{5 is} an alkylene group having 3 to 30 carbon atoms, and R ⁶ is a 1 to 20 carbon atom.
Wherein n represents an integer of 1 to 20; ) Which contains at least one type of monomer selected from the group represented by (1).

Specific examples of the alkyl acrylate represented by the general formula (1) include, for example, methyl acrylate, ethyl acrylate, propyl acrylate,
Examples thereof include butyl acrylate, pentyl acrylate, hexyl acrylate, actyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, dodecyl acrylate, and cyanoethyl acrylate.

Examples of the alkoxyalkyl acrylate represented by the general formula (2) include methoxyethyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate, and ethoxypropyl acrylate. One or more of these can be used as the main component of the acrylic rubber.

As a component of the acrylic rubber of the component (B) of the present invention, if necessary, the above general formulas (1) to (3)
An unsaturated monomer copolymerizable with at least one monomer selected from the compounds represented by the following formula (1) can be used. Examples of such unsaturated monomers include styrene, α-methylstyrene, acrylonitrile, halogenated styrene, methacrylonitrile, acrylamide, methacrylamide, vinylnaphthalene, N-methylolacrylamide, vinyl acetate, vinyl chloride, chloride Vinylidene, benzyl acrylate, methacrylic acid, itaconic acid, fumaric acid, maleic acid and the like.

The preferred constituent ratio of the acrylic rubber having a functional group capable of reacting with the liquid crystal polyester of the component (B) of the present invention is at least one selected from the compounds represented by the above general formulas (1) to (3). One kind of monomer 40-99.9
Wt%, unsaturated carboxylic acid glycidyl ester and / or
Or 0.1 to 30% by weight of unsaturated glycidyl ether,
It is 0 to 30% by weight of an unsaturated monomer copolymerizable with at least one monomer selected from the compounds represented by the above general formulas (1) to (3). When the constituent ratio of the acrylic rubber is within the above range, heat resistance and impact resistance of the composition,
The molding processability is good and preferable.

The method for producing the acrylic rubber is not particularly limited. For example, JP-A-59-113010, JP-A-62-64809, and JP-A-3-160008
Or a well-known polymerization method described in WO95 / 04764 or the like, and can be produced by emulsion polymerization, suspension polymerization, solution polymerization or bulk polymerization in the presence of a radical initiator. .

The acrylic rubber of the component (B) in the present invention preferably has a Mooney viscosity of 3 to 70, and preferably 4 to 6
0 is more preferred. The Mooney viscosity here refers to a value measured using a large rotor at 100 ° C. according to JIS K6300.

The ratio of component (A) to component (B) in the liquid crystal polyester resin composition used in the present invention is such that component (A) is 56 to 99% by weight, preferably 65 to 98% by weight, more preferably 70 to 98% by weight. The content of the component (B) is 44 to 1% by weight, preferably 35 to 2% by weight, and more preferably 30 to 3% by weight. If the content of the component (A) is less than 56% by weight, the heat resistance of the composition is undesirably reduced. If the content of the component (A) exceeds 99% by weight, the effect of improving the film-forming properties of the composition may not be sufficient, and the cost is high, which is not preferable.

The method for producing the liquid crystal polyester resin composition of the present invention is not particularly limited, and a known method can be used. For example, mixing each component in the molten state,
Examples of the method include evaporating the solvent or precipitating the solvent. From an industrial point of view, there is a method of kneading each component in a molten state. From an industrial point of view, a method of kneading each component in a molten state is preferred. For the melt kneading, kneading apparatuses such as a single-screw or twin-screw extruder and various kneaders which are generally used can be used. In particular, a biaxial high kneader is preferred. At the time of melt-kneading, the cylinder set temperature of the kneading device is preferably in the range of 200 to 360 ° C, more preferably 230 to 350 ° C.

At the time of kneading, the respective components may be previously mixed uniformly with a device such as a tumbler or a Hensle mixer. If necessary, the mixing may be omitted and the components may be separately added to the kneading device. Can also be used.

In the liquid crystal polyester resin composition used in the present invention, an inorganic filler is used if desired.
Examples of such inorganic fillers include calcium carbonate, talc, clay, silica, magnesium carbonate, barium sulfate, titanium oxide, alumina, gypsum, glass flake, glass fiber, carbon fiber, alumina fiber, silica alumina fiber, and aluminum borate. Examples include whiskers and potassium titanate fibers.

The liquid crystal polyester resin composition used in the present invention may further contain, if necessary, an organic filler, an antioxidant, a heat stabilizer, a light stabilizer, a flame retardant, a lubricant, an antistatic agent,
Various additives such as inorganic or organic colorants, rust inhibitors, cross-linking agents, foaming agents, fluorescent agents, surface smoothing agents, surface gloss improvers, release improvers such as fluororesins, etc. during or after the manufacturing process It can be added in the processing step.

Usually, a liquid crystal polyester resin composition film can be obtained by melt-kneading the liquid crystal polyester resin composition obtained by the above-mentioned method with an extruder and collecting the molten resin extruded through a die. However, without going through the kneading process in advance, dry blending each component at the time of molding and kneading during the melt processing operation to form a resin composition,
Direct molded products can also be obtained. As the die, a T-shaped die (hereinafter sometimes referred to as a T-die) or an annular slit die can be used.

In the case of film formation using a T-die, the liquid crystal polyester resin composition melt-kneaded by an extruder usually passes through a downward T-die to form a sheet-like melt, which is then passed through a press roll in the longitudinal direction. Is taken up by the take-up device.

The setting conditions of the extruder at the time of such film formation are appropriately selected according to the composition of the composition. The setting temperature of the cylinder of the extruder is preferably in the range of 200 to 360 ° C., and is preferably in the range of 230 to 350 ° C. The range of ° C. is more preferable. If the ratio is out of this range, the composition may be thermally decomposed or film formation may be difficult, which is not preferable.

The slit interval of the T-die (2) is 0.2 to
1.2 is preferred. The thickness of the liquid crystal polyester resin composition film of the present invention can be controlled in the range of 1 to 1000 μm, but those having a thickness of 5 to 100 μm are practically preferred and are preferred. The draft ratio of the liquid crystal polyester resin composition film of the present invention is in the range of 1.1 to 40.0. Also, a biaxially stretched film of the resin composition extruded from a T-die can be obtained.

The method of biaxial stretching in the production of the liquid crystal polyester resin composition film of the present invention is not particularly limited. Specifically, a melt of the composition of the present invention extruded from a T die of an extruder is machined in the MD direction. Uniaxially stretched (longitudinal direction),
Then, successive stretching in the TD direction (lateral direction), T
Simultaneous stretching, in which the sheet extruded from the die is simultaneously stretched in the MD and TD directions, and biaxial stretching, such as sequential or simultaneous stretching of an unstretched sheet extruded from the T die with a biaxial stretching machine, a tenter or the like, are also available. No.

In any case, the film forming temperature is preferably in the temperature range of the flow start temperature of the liquid crystal polyester resin composition of the present invention minus 60 ° C. or more, and the flow start benefit plus 60 ° C. or less. It is more preferable that the film is formed in a temperature range of 30 ° C. or less plus the flow start.

The slit interval of the T die is 0.2 m
m to 1.2 mm is preferred. An appropriate value is determined for the stretching ratio according to the molding method. For example, in the case of stretching with a biaxial stretching machine, if the stretching ratio is defined as (length after stretching / original length), MD stretching direction, TD The stretching ratio in each of the directions is 1.2 to 20.0, preferably 1.5 to 5.0.
Is used. If the stretching ratio is smaller than 1.2, the stretching effect is small, and if it is larger than 20.0, the smoothness of the film may be insufficient.

In the case of inflation molding (film formation) using an annular slit die, the obtained liquid crystal polyester resin composition is supplied to a melt kneading extruder equipped with an annular slit die, and set at a cylinder set temperature of 200 to 360.
C., preferably 230 to 350.degree. C., and the molten resin is extruded upward or downward through the annular slit of the extruder. The annular slit interval is usually 0.1 to 5 mm, preferably 0.2 to 2 mm, and the diameter of the annular slit is usually 20 to 1000 mm, preferably 25.
６００600 mm.

The molten extruded cylindrical molten resin film is drafted in the longitudinal direction (MD), and air or an inert gas, for example, nitrogen gas, is blown from the inside of the cylindrical film so that the longitudinal direction is reduced. The film can be stretched and stretched in a transverse transverse direction (TD). In the inflation molding (film formation) of the liquid crystal polyester resin composition in the present invention, a preferable blow ratio is 1.5 to 10, and a preferable MD stretching ratio is 1.5 to 40.
It is. If the setting conditions during the inflation film formation are outside the above range, it is difficult to obtain a high-strength liquid crystal polyester resin composition film having a uniform thickness and no wrinkles, which is not preferable. After the circumference of the expanded film is air-cooled or water-cooled, the film is passed through a nip roll and taken out.

Upon inflation film formation, conditions can be selected according to the composition of the liquid crystal polyester resin composition such that the cylindrical molten film expands to a uniform thickness and a smooth surface state.

The thickness of the liquid crystal polyester resin composition film obtained by the present invention is not particularly limited, but is preferably 1 to 500 μm, more preferably 1 to 200 μm.
It is.

In the present invention, a liquid crystal polyester resin composition film and (C) a thermoplastic resin (excluding liquid crystal polyester and liquid crystal polyester resin composition)
A film obtained by laminating a film with a T-die method or an inflation method can also be obtained. The thermoplastic resin here is not particularly limited as long as it is other than liquid crystal polyester or liquid crystal polyester resin composition, but polyethylene, polypropylene, ethylene-α-
Polyolefin such as olefin copolymer, polystyrene, polycarbonate, polyester such as polyethylene terephthalate and polybutylene terephthalate, polyacetal, polyamide, polyphenylene ether, polyether sulfone, ethylene vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, polyphenylene Sulfide, fluororesin and the like are preferably used. Among them, polyethylene, polypropylene, ethylene-α-olefin copolymer and polyethylene terephthalate are more preferred. As the thermoplastic resin, one type or a mixture of two or more types can be formed into a film. The thermoplastic resin in the present invention includes a thermoplastic resin modified by introducing a functional group into a molecular chain.

The method for producing the laminated film is not particularly limited, but a method in which the molten resin of each component is superposed in the die and then extruded from the die, and each molten resin is extruded from the die and then superposed. A method or a method in which the respective melted resins are superposed in front of the die and then extruded from the die can be used, and the production method can be selected according to the purpose. Alternatively, a laminated film can be obtained by dry laminating a liquid crystal polyester resin composition film and a thermoplastic resin film.

[0057]

EXAMPLES The present invention will be described below with reference to examples, but these are merely examples, and the present invention is not limited to these examples.

(1) Liquid crystal polyester of component (A) (i) 8.3 kg (60 mol) of p-acetoxybenzoic acid, 2.49 kg (15 mol) of terephthalic acid, 0.83 kg (5 mol) of isophthalic acid and 4 5,45 kg (20.2 mol) of 4,4'-diacetoxydiphenyl was charged into a polymerization tank having a comb-shaped stirring blade, and the temperature was increased while stirring under a nitrogen gas atmosphere, and polymerization was performed at 330 ° C. for 1 hour. During this time, the polymerization was carried out under vigorous stirring while removing acetic acid produced as a by-product. Thereafter, the system was gradually cooled, and the polymer obtained at 200 ° C. was taken out of the system. The obtained polymer was pulverized with a hammer mill manufactured by Hosokawa Micron Co., Ltd.
The following particles were used. This was further treated in a rotary kiln under a nitrogen gas atmosphere at 280 ° C. for 3 hours to obtain a particulate wholly aromatic polyester having a flow temperature of 324 ° C. and comprising the following repeating structural units. Here, the flow temperature refers to a high flow type flow tester CFT-5 manufactured by Shimadzu Corporation.
Using a mold 00, a resin heated at a temperature rising rate of 4 ° C./min was applied under a load of 100 kgf / cm ² to an inner diameter of 1 mm.
The temperature at which the melt viscosity shows 48,000 poise when extruded from a nozzle having a length of 10 mm.

Hereinafter, the liquid crystal polyester is abbreviated as A-1. This polymer showed optical anisotropy at 340 ° C. or more under pressure. The repeating structural units of the liquid crystal polyester A-1 are as follows.

(Ii) p-hydroxybenzoic acid 16.6k
g (121 mol), 8.4 kg (45 mol) of 6-hydroxy-2-naphthoic acid and 18.6 kg of acetic anhydride
(182 mol) was charged into a polymerization vessel equipped with a comb-shaped stirring blade, and the temperature was increased while stirring under a nitrogen gas atmosphere, and the polymerization was performed at 320 ° C. for 1 hour, and further at 320 ° C. for 1 hour under a reduced pressure of 2.0 torr. Was. During this time, acetic acid produced as a by-product was continuously distilled out of the system. Thereafter, the system was gradually cooled, and the polymer obtained at 180 ° C. was taken out of the system. The obtained polymer is pulverized in the same manner as in the above (i), and then treated in a rotary kiln under a nitrogen gas atmosphere at 240 ° C. for 5 hours to obtain a particulate repeating unit having a flow temperature of 270 ° C. Was obtained. Hereinafter, the liquid crystal polyester is abbreviated as A-2. This polymer showed optical anisotropy at 280 ° C. or more under pressure.

The ratio of the repeating structural units of the liquid crystal polyester A-2 is as follows.

(2) Component (B) (i) Epoxy-containing acrylic rubber Nipol AR31 manufactured by Zeon Corporation (Mooney viscosity (100 ° C.) = 36) Hereinafter, it may be abbreviated as B-1.

(Ii) Epoxy-containing acrylic rubber Nipol AR51 manufactured by Zeon Corporation (Mooney viscosity (100 ° C.) = 55) Hereinafter, it may be abbreviated as B-2.

(3) Method of Measuring Physical Properties of Injection-Molded Product Deflection temperature under load (TDUL): A test piece for measuring TDUL (127 mm length × 12.7 mm width × 6.4 mm thickness) is molded, and TDUL is measured according to ASTM D648. (Load 1
8.6 kg).

(4) Method for measuring physical properties of film Oxygen gas permeability: JIS K7126 A method (differential pressure method)
The measurement was carried out at a temperature of 20 ° C. in accordance with The unit is cc /
m ² · 24 hr · latm.

Water vapor transmission rate: Measured at a temperature of 40 ° C. and a relative humidity of 90% according to JIS Z0208 (cup method). The unit is g / m ² · 24 hr · latm. The oxygen gas transmission rate and the water vapor transmission rate were determined by setting the film thickness to 2
It was determined by converting to 5 μm.

Thermal decomposition temperature: Thermo, manufactured by Shimadzu Corporation
gravimetric Analyzer TGA-
Using a Model 50, the temperature at which thermal decomposition was initiated was determined for 10 mg of the shredded film by raising the temperature at 10 ° C./min in a nitrogen atmosphere.

Examples 1 to 3 and Comparative Examples 1 to 4 Each of the components having the composition shown in Table 1 was mixed with a Henschel mixer, and the mixture was mixed with a TEX-30 type twin screw extruder manufactured by Nippon Steel Corporation.
Cylinder temperature described, screw rotation speed 180r
The composition was obtained by melt-kneading at pm. The composition was subjected to injection molding using a PS40E5ASE type injection molding machine manufactured by Nissei Plastic Industry Co., Ltd. at a cylinder set temperature and a mold temperature of 80 ° C. shown in Table 1. The pellets of this composition were melt-kneaded using a 30 mmφ single screw extruder equipped with a cylindrical die at the cylinder set temperature shown in Table 1 and at a rotation speed of 50 rpm. The molten resin is extruded upward from a cylindrical die at a set temperature, dry air is pressed into the hollow portion of the cylindrical film to expand the cylindrical film, and then cooled and then passed through a nip roll at a take-up speed of 9 m / min. Tensile, a liquid crystal polyester resin composition film was obtained. The stretching ratio of the liquid crystal polyester resin composition film in the take-up direction (MD direction) and the direction perpendicular to the take-up direction (TD direction) was controlled by the amount of dry air to be injected and the film take-up speed. At this time, take-up speed, MD
The stretching ratio in the direction, the blow ratio in the TD direction, and the film thickness are as shown in Table 1. Table 1 shows the physical property values of the obtained liquid crystal polyester resin composition film.

[0069]

[Table 1]

[0070]

[Table 2]

[0071]

According to the liquid crystal polyester resin composition used in the present invention, the unique viscosity behavior upon melting, which was a disadvantage of liquid crystal polyester, has been improved, and molding processability such as film forming is easy. By film-forming the liquid crystal polyester resin composition by the method according to the present invention, excellent mechanical properties of liquid crystal polyester, heat resistance,
In addition, a practical film which retains functions such as gas barrier properties and the like, has excellent thermal stability, and is inexpensive and practical can be obtained.

The liquid crystal polyester resin composition film of the present invention makes use of such characteristics as a gas barrier film, a heat resistant film, etc., specifically, a food packaging film, a chemical packaging film, a cosmetic packaging film, an electronic material packaging film, etc. Can be used widely. Furthermore, by selecting an appropriate material from the liquid crystal polyester and the thermoplastic resin as raw materials, it is possible to obtain a film which is easy to dispose of an element consisting of only carbon, hydrogen and oxygen, and has the above-mentioned excellent properties. .

Claims (11)

[Claims] 1. A liquid crystal polyester resin composition comprising (A) 56 to 99% by weight of a liquid crystal polyester and (B) 1 to 44% by weight of an acrylic rubber having a functional group capable of reacting with the liquid crystal polyester. 2. A functional group capable of reacting with a liquid crystal polyester,
The liquid crystal polyester resin composition according to claim 1, which is an epoxy group. 3. The method according to claim 1, wherein the acrylic rubber (B) having a functional group capable of reacting with the liquid crystal polyester contains an unsaturated glycidyl carboxylate unit and / or an unsaturated glycidyl ether unit. Liquid crystal polyester resin composition. 4. An acrylic rubber (B) having a functional group capable of reacting with a liquid crystal polyester is at least one selected from monomers represented by the following general formulas (1) to (3): The liquid crystal polyester resin composition according to any one of claims 1 to 3, wherein the composition is a main component. (In the formula, R ¹ represents an alkyl group having 1 to 18 carbon atoms or a cyanoalkyl group.) (Wherein, R ² is an alkylene group having 1 to 12 carbon atoms;
³ represents an alkyl group having 1 to 12 carbon atoms. ) (Wherein R ⁴ is a hydrogen atom or a methyl group, R ^{5 is} an alkylene group having 3 to 30 carbon atoms, and R ⁶ is a 1 to 20 carbon atom.
Wherein n represents an integer of 1 to 20; ) 5. An acrylic rubber (B) comprising 40 to 99.9% by weight of an alkyl acrylate and / or an alkoxyalkyl acrylate, and 0.1 to 30 unsaturated glycidyl carboxylate and / or unsaturated glycidyl ether. 2. The liquid crystal polyester resin composition according to claim 1, which is obtained by copolymerizing 0 to 30% by weight of a monomer copolymerizable with an alkyl acrylate and / or an alkoxyalkyl acrylate. . 6. The liquid crystal polyester resin composition according to claim 1, wherein the component (B) is an acrylic rubber having a Mooney viscosity in the range of 3 to 70. The Mooney viscosity as used herein refers to a value measured at 100 ° C. using a large rotor according to JIS K6300. 7. The liquid crystal polyester resin composition according to claim 1, wherein the liquid crystal polyester (A) contains at least 30 mol% of the following repeating structural units. 8. The liquid crystal polyester (A) according to claim 1, which is obtained by reacting an aromatic dicarboxylic acid, an aromatic diol and an aromatic hydroxycarboxylic acid. The liquid crystal polyester resin composition according to the above. 9. The liquid crystal polyester resin composition according to claim 1, wherein the liquid crystal polyester (A) is obtained by reacting a combination of different aromatic hydroxycarboxylic acids. Stuff. 10. A melt extruded from a T-die.
10. A film obtained by uniaxially or biaxially stretching the liquid crystal polyester resin composition according to item 9. 11. A film obtained by inflation molding the liquid crystal polyester resin composition according to claim 1.