JP3029890B2 - Liquid crystalline polymer composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystalline polymer composition which can be easily molded.

[0002]

2. Description of the Related Art Liquid crystalline polymers are characterized by heat resistance, mechanical properties, durability, electrical properties,
Because of its excellent dimensional stability, it is used as an engineering plastic. In addition, since liquid crystal polymers are excellent in chemical stability, gas barrier properties, and the like, utilization as a film forming material is also being studied.

On the other hand, since the liquid crystalline polymer has higher heat resistance than a general molding polymer, it needs to be molded at a high temperature. Further, not only the decomposition temperature of the liquid crystalline polymer and the molding temperature are close to each other, but also the melt viscosity of the liquid crystalline polymer is high and the fluidity is small. For this reason, the melt-molding processability of the liquid crystalline polymer is not sufficient, and it is difficult to obtain precision parts and films with excellent accuracy at a relatively low temperature.

Accordingly, an object of the present invention is to provide a liquid crystal polymer composition which can form a liquid crystal polymer at a relatively low temperature with high precision.

[0005]

The present inventors have found the configuration of the invention] As a result of intensive investigations to achieve the above object, the addition of certain compounds to a particular thermotropic liquid crystal polymer, found that be molded at relatively low temperatures, the present invention completed. That is, the present invention relates to a thermotropic liquid crystalline polymer, and the following general formula [I]

[0006]

Embedded image [Wherein, R ¹ and R ² are alkyl groups, and R ³ and R ⁴ are
The same or different, and represents a hydrogen atom, an alkyl group, or a halogen atom. Z is a monocyclic aromatic hydrocarbon residue (provided that
1,4-phenylene group), condensed polycyclic aromatic carbonized
Indicates a hydrogen residue. The monocyclic aromatic hydrocarbon residue
(Excluding 1,4-phenylene group) and condensed polycyclic aromatic
The hydrocarbon may have a substituent. X ¹ , X ² , X
³ and X ⁴ each represent an ester bond].
The thermotropic liquid crystalline polymer has the following repeating structure.
It has the unit [X] and / or [XI].

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[0007] In the present specification, the term "liquid crystalline polymer" means a thermotropic liquid crystal polymer which is softened and flowable by heating and can be molded, and exhibits an anisotropic molten phase having a birefringence when melted, and a composition thereof. .

In the compound represented by the general formula [I], examples of the alkyl group represented by R ¹ and R ² include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, Examples thereof include straight-chain or branched-chain alkyl groups such as hexyl, heptyl, octyl, nonyl, decyl and dodecyl groups. Among these alkyl groups, an alkyl group having 1 to 10 carbon atoms, particularly an alkyl group having about 1 to 6 carbon atoms, is frequently used.

Examples of the alkyl group represented by R ³ and R ⁴ include the same alkyl groups as described above. Preferred substituents R ³ and R ⁴ are a hydrogen atom and a methyl group. Halogen atoms include fluorine, chlorine, bromine and iodine atoms. Preferred halogen atoms are a chlorine atom and a bromine atom.

The monocyclic aromatic hydrocarbon constituting the group Z
Is a 1,2-phenylene, 1,3-phenylene group, etc.
included. Condensed polycyclic aromatic hydrocarbon residues include naphthale
, Anthracene, phenanthrene, pyrene, chrysene
And so on. The preferred Imoto Z, for example, 1,3
It includes a phenylene group and a naphthalene residue. The group Z may be substituted with a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a phenyl group, or the like.

The ester bond represented by X ¹ , X ² , X ³ and X ⁴ may be any of —OOC— and —COO—.

The compound represented by the general formula [I] can be obtained, for example, according to the following reaction formulas (1), (2) and (3).

[0013]

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[0014]

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[0015]

Embedded image (In the formula, X represents a halogen atom. R ^{1 to} R ⁴ , Z and X ^{1 to} X ⁴ are the same as described above.) Each reaction in the reaction formulas (1), (2) and (3) is usually carried out in an organic solvent. It is done in. Examples of the organic solvent include aliphatic hydrocarbons such as hexane and octane; alicyclic hydrocarbons such as cyclohexane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated carbons such as chloroform, carbon tetrachloride, and dichloroethane. Hydrogen; esters such as methyl acetate and ethyl acetate; ketones such as acetone, methyl ethyl ketone and cyclohexanone; ethers such as diethyl ether and tetrahydrofuran; mixed solvents thereof.

The general formulas [II] and [IV] and the general formula [V
The amount of the compound represented by the general formula [I]
With respect to 1 mole of the compound represented by I], [IV] or [VI], the total number of moles of the compound represented by the general formulas [IIIa] or [IIIb] or the general formula [Va] or [Vb] The total number of moles of the compound represented, and the general formula [VIIa]
When the total number of moles of the compound represented by [VIIb] is from 2 to 2.5
It is about a mole.

The reaction can be carried out, for example, at a temperature from room temperature to 150 ° C., preferably from about 50 to 120 ° C., and is usually completed in about 1 to 24 hours.

General formula [II] [Va] [Vb] [VI]
And [VIIb] can be obtained by reacting a corresponding aromatic carboxylic acid with a halogenating agent, for example, thionyl chloride, phosphorus pentachloride or the like.

The content of the compound represented by the general formula [I] can be determined, for example, by thermotropic liquid crystalline polymer 100
0.1 to 50 parts by weight, preferably 1 to 2 parts by weight
It is about 5 parts by weight. If the content of the compound represented by the general formula [I] is less than 0.1 part by weight, the melting point and the fluidity are not significantly improved, and if it exceeds 50 parts by weight, the mechanical properties of the thermotropic liquid crystalline polymer are increased. And heat resistance is easily impaired.

The compound represented by the general formula [I] has excellent compatibility with a liquid crystalline polymer. Further, even when the compound represented by the general formula [I] is added to the liquid crystalline polymer,
The excellent properties of the liquid crystalline polymer, for example, heat resistance, mechanical strength, gas barrier properties, etc. are not significantly impaired.

The thermotropic liquid crystalline polymer is
It has a repeating structural unit [X] and / or [XI].

The liquid crystalline polymer used in the present invention is have a birefringence soluble Toruji.

Preferred fully aromatic polyesters are generally solvent shows a tendency is substantially insoluble, it is not suitable for solution processing. However, these polymers can be easily processed by conventional melt processing methods. It should be noted that particularly preferred fully aromatic polyesters are somewhat soluble in pentafluorophenol.

The liquid crystalline polymer may have an appropriate molecular weight within a range that does not impair moldability, film formability and the like. For example, the molecular weight of a suitable wholly aromatic polyester is usually
The weight average molecular weight is about 2,000 to 200,000, preferably about 10,000 to 50,000, and particularly preferably about 20,000 to 25,000. The molecular weight can be measured by gel permeation chromatography, quantification of terminal groups by infrared spectroscopy, light scattering using pentafluorophenol as a solvent, and the like.

[0025] In particular polymer forming the preferred anisotropic melt phase, 6-hydroxy-2-Nafutoi Le units about 10
It is contained in an amount of at least mol% .

[0026] More specifically, about the unit [X] 10~9
0 mol% and the unit [XI] is about 10 to 90 mol%
contains. In one embodiment, unit [X] is present in an amount up to about 65-85 mol% (eg, about 75 mol%). In another embodiment, the unit [XI] is present in a low amount of about 15-35 mol%, preferably about 20-30 mol%.

[0027] At least part of hydrogen atoms bonded Oite, the ring to the liquid crystalline polyester Le is from 1 to 4 carbon atoms
May be substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a halogen atom, a phenyl group, and a substituted phenyl group.

[0028] Among these thermotropic liquid crystalline polymers, polyester consisting especially in recurring structural units [X] and [XI] are preferable.

The liquid crystalline polymer usually has a heat distortion temperature of 12
0 to 400 ° C., preferably about 150 to 350 ° C., and the elastic modulus 1 × 10 ⁵ kgf / cm ² or more, a tensile strength of 2,000 kgf / cm ² or more, excellent heat resistance and mechanical properties. Particularly, a liquid crystalline polymer having a heat distortion temperature of 150 to 250 ° C. is preferable as a film forming material because of its excellent film formability. At a film thickness of 25 μm, the film made of a liquid crystalline polymer has an oxygen gas and carbon dioxide gas permeability of 1.0 cc / m ² · 24 hours · atmospheric pressure, and a water vapor transmission rate of about 1.5 g / m ² · 24 hours · atmospheric pressure or less. Yes,
Excellent gas barrier properties. Furthermore, the dimensions are 0.003 to 500 ° C. even when left for 500 hours at a temperature of 70 ° C. and a relative humidity of 96%.
It is deformed by only about 0.02% and has excellent dimensional stability.

The liquid crystalline polymer may be used in combination with another thermotropic liquid crystalline polymer. When another thermotropic liquid crystalline polymer is used in combination, the content of the thermotropic liquid crystalline polymer is preferably 80% by weight or more in all the liquid crystalline polymers. If the content of the other liquid crystalline polymer exceeds 20% by weight, the compatibility with the compound represented by the above general formula [I] may be reduced.

The liquid crystalline polymer that can be used in combination with the above liquid crystalline polyester is not particularly limited, and examples thereof include aromatic polyazomethine. Further, the liquid crystalline polymer composition of the present invention may contain at least one of a thermoplastic resin, a thermosetting resin, a low molecular weight organic compound, and an inorganic substance that do not form an anisotropic molten phase. The polymer forming the anisotropic molten phase in the composition and other components may be thermodynamically compatible.

The liquid polymer composition of the present invention maintains the mechanical properties, heat resistance, gas barrier properties, dimensional stability, chemical stability, the characteristics of the liquid crystal polymer, such as chemical resistance and electrical properties And has a low melting point and excellent fluidity. Therefore, the liquid crystalline polymer composition can melt-mold precision parts and films at a relatively low temperature with high precision.

The liquid polymer composition of the present invention is suitable as a packaging film forming materials. Films formed using the liquid crystalline polymer composition can be used as individual packaging of various objects to be packaged, interior, exterior, bag-making films, for example, retort foods, food packaging materials such as microwave oven foods, In addition to packaging materials for oily cooking materials, packaging materials for medicines, packaging materials for cosmetics, and fragrance-retaining packaging materials for aromatic substances, for example, desks,
It can be applied to various uses such as a protective film for a laboratory bench.

[0034]

Since the composition of the present invention contains a thermotropic liquid crystalline polymer and a specific compound, it can be molded accurately at a relatively low temperature without deteriorating the properties of the liquid crystalline polymer.

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to embodiments.

[0036] Examples 1 and 2 2,6-naphthalene dicarboxylic acid 1 mol of the thionyl chloride 2.1 mol, in tetrahydrofuran containing dimethylformamide 0.05 mol, is 2.5 hours at 60 ° C., 2, 6-Naphthalenedicarboxylic acid chloride was produced, 2 mol of methyl p-hydroxybenzoate was added to the reaction mixture, and the mixture was reacted at 60 ° C. for 2 hours to obtain the following compound.

[0037]

Embedded image Examples 3 and 4 The following compounds were obtained in the same manner as in Example 1 except that ethyl p-hydroxybenzoate was used instead of methyl p-hydroxybenzoate.

[0038]

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[0039] except that isophthalic acid in place of Example 5 and 6 2,6-naphthalene dicarboxylic acid, Example 1
The reaction was carried out in the same manner as described above.

[0040] The repeating units [X], and [XI] polyester Le or Ranaru liquid crystalline polymer comprised of (poly plastic Co., Ltd., trade name VECTRA A900), obtained by the Examples and Comparative Examples After mixing the compound with the compound at the ratio shown in Table 1 , the mixture was heated at 285 ° C. and 50 rpm using a Brabender plastograph (manufactured by Brabender).
Was melt-kneaded for 5 minutes to prepare a liquid crystalline polymer composition.

COMPARATIVE EXAMPLE A liquid crystalline polymer composition obtained by adding the compound obtained in the above-mentioned example without adding the compound was used as a comparative example.

[0042] and, capillograph (Toyo Seiki Co., Ltd.
And the melting point was measured using a differential scanning calorimeter (manufactured by Seiko Denshi Co., Ltd., Model DSC200).

The melt viscosity according to the capillograph is as follows:
The measurement was carried out using a capillary having a diameter of 0.5 mm and a length of 5.0 mm at a shear rate of 1000 sec ^-1 . Also,
Melt viscosity was measured at measurement temperatures of 270 ° C and 280 ° C. Table 1 shows the results.

[0044]

[Table 1] As can be seen from the table, the addition of a small amount of the compound to the liquid crystalline polyester lowers the melt viscosity and the melting point.

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C08L 67/00 C08K 5/10 C09K 19/38

Claims (1)

(57) [Claims] 1. A thermotropic liquid crystalline polymer and a compound represented by the following formula [I]: [Wherein, R ¹ and R ² are alkyl groups, and R ³ and R ⁴ are
The same or different, and represents a hydrogen atom, an alkyl group, or a halogen atom. Z is a monocyclic aromatic hydrocarbon residue (provided that
1,4-phenylene group), condensed polycyclic aromatic carbonized
Indicates a hydrogen residue. The monocyclic aromatic hydrocarbon residue
And the condensed polycyclic aromatic hydrocarbon has a substituent
Is also good. A X ^1, X ^2, X ³ and X ⁴ pairs formed product you containing a compound is represented by each represent an ester bond, the thermotropic liquid crystal polymer is, following repeated
Liquid crystalline polymer containing structural unit [X] and / or [XI]
-Composition . Embedded image Embedded image