JP2004277731A - Aromatic liquid crystal polyester solution composition - Google Patents

Abstract

（式中、Ａはハロゲン原子またはトリハロゲン化メチル基を表わし、ｉはＡの個数であって１〜５の整数を表わし、ｉが２以上の場合に複数あるＡは互いに同一でも異なっていてもよい。）
【選択図】 なし
PROBLEM TO BE SOLVED: To provide an aromatic liquid crystal polyester solution composition capable of producing a film having more excellent film-forming properties and a good surface condition.
An aromatic liquid crystal polyester solution composition obtained by dissolving 0.5 to 100 parts by weight of an aromatic liquid crystal polyester at a temperature higher than 120 ° C and lower than 160 ° C with respect to 100 parts by weight of the following solvent.
Solvent: Solvent containing a halogen-substituted phenol compound represented by the following general formula (I).

(Wherein, A represents a halogen atom or a trihalogenated methyl group, i represents the number of A and represents an integer of 1 to 5, and when i is 2 or more, a plurality of As are the same or different. May be.)
[Selection diagram] None

Description

  The present invention relates to an aromatic liquid crystalline polyester solution composition.

Aromatic liquid crystal polyesters are widely used mainly in precision electronic components such as connectors obtained by injection molding because of their excellent low moisture absorption, high frequency characteristics, heat resistance, and mechanical strength. In recent years, it has been studied to form an aromatic liquid crystal polyester into a film by extrusion molding such as T-die molding or inflation molding and to use the film for an insulating film of a multilayer printed board or a flexible printed board.
However, the conventional aromatic liquid crystal polyester film obtained by extrusion molding has a large anisotropy at the time of molding, a very low tear strength in a direction perpendicular to the flow direction at the time of molding, and breakage occurs during handling of the film. There was a problem.
As a method for solving this problem, an aromatic liquid crystal polyester film obtained by casting a solution containing an aromatic liquid crystal polyester and a solvent containing a halogen-substituted phenol and then removing the solvent is known. (Patent Document 1).

JP-A-2002-114894

  Although the film obtained by the method described in Patent Document 1 has small anisotropy and excellent tear strength in the direction perpendicular to the flow direction during molding, it still has improved film-forming properties and film surface conditions. Room was left. An object of the present invention is to provide an aromatic liquid crystal polyester solution composition which is more excellent in film-forming properties and can produce a film having a good surface condition.

（式中、Ａはハロゲン原子またはトリハロゲン化メチル基を表わし、ｉはＡの個数であって１〜５の整数を表わし、ｉが２以上の場合に複数あるＡは互いに同一でも異なっていてもよい。） That is, the present invention relates to an aromatic liquid crystal polyester solution composition obtained by dissolving 0.5 to 100 parts by weight of an aromatic liquid crystal polyester at a temperature higher than 120 ° C and lower than 160 ° C with respect to 100 parts by weight of the following solvent. Such is the case.
Solvent: Solvent containing a halogen-substituted phenol compound represented by the following general formula (I).

(Wherein, A represents a halogen atom or a trihalogenated methyl group, i represents the number of A and represents an integer of 1 to 5, and when i is 2 or more, a plurality of As are the same or different. May be.)

  ADVANTAGE OF THE INVENTION According to this invention, the aromatic liquid crystal polyester solution composition which is excellent in film-forming property and can manufacture a film with favorable surface state is provided.

  The aromatic liquid crystal polyester used in the present invention is a polyester called a thermotropic liquid crystal polymer, and forms a melt showing optical anisotropy at a temperature of 450 ° C. or lower.

As the aromatic liquid crystal polyester, for example,
(1) those obtained by polymerizing a combination of an aromatic hydroxycarboxylic acid, an aromatic dicarboxylic acid and an aromatic diol;
(2) those obtained by polymerizing different kinds of aromatic hydroxycarboxylic acids,
(3) those obtained by polymerizing a combination of an aromatic dicarboxylic acid and an aromatic diol,
(4) A polyester obtained by reacting an aromatic hydroxycarboxylic acid with a crystalline polyester such as polyethylene terephthalate.
In addition, instead of these aromatic hydroxycarboxylic acids, aromatic dicarboxylic acids, or aromatic diols, ester-forming derivatives thereof may be used.

Examples of the carboxylic acid ester-forming derivatives include, for example, those in which a carboxyl group is a highly reactive derivative such as an acid chloride or an acid anhydride that promotes a polyester formation reaction, or a carboxyl group is an ester. Examples thereof include those which form an ester with alcohols, ethylene glycol, and the like that generate a polyester by an exchange reaction.
Examples of the ester-forming derivative of the phenolic hydroxyl group include, for example, those in which the phenolic hydroxyl group forms an ester with a carboxylic acid so as to form a polyester by a transesterification reaction.

  In addition, aromatic hydroxycarboxylic acids, aromatic dicarboxylic acids and aromatic diols are halogen atoms such as a chlorine atom and a fluorine atom, alkyl groups such as a methyl group and an ethyl group, and phenyl, as long as they do not inhibit ester-forming properties. May be substituted with an aryl group such as a group.

  Examples of the repeating structural unit of the aromatic liquid crystal polyester include the following, but are not limited thereto.

上記の繰り返し構造単位は、ハロゲン原子またはアルキル基で置換されていてもよい。 Repeating structural unit derived from aromatic hydroxycarboxylic acid:

The above repeating structural unit may be substituted with a halogen atom or an alkyl group.

上記の繰り返し構造単位は、ハロゲン原子、アルキル基またはアリール基で置換されていてもよい。 Repeating structural unit derived from aromatic dicarboxylic acid:

The above repeating structural unit may be substituted with a halogen atom, an alkyl group or an aryl group.

上記の繰り返し構造単位は、ハロゲン原子、アルキル基またはアリール基で置換されていてもよい。 Repeating structural unit derived from aromatic diol:

The above repeating structural unit may be substituted with a halogen atom, an alkyl group or an aryl group.

  In addition, as said alkyl group, a C1-C10 alkyl group is preferable and a methyl group, an ethyl group, or a butyl group is more preferable. The aryl group is preferably an aryl group having 6 to 20 carbon atoms, and more preferably a phenyl group.

Heat resistance, aromatic liquid crystal polyester from the balance of mechanical properties, preferably contains a repeating unit represented by A ₁ expression at least 30 mol%.
Preferred combinations of the repeating structural units include, for example, the following (a) to (f).
(A):
A combination of the repeating structural units (A ₁ ), (B ₂ ) and (C ₃ );
A combination of the repeating structural units (A ₂ ), (B ₂ ) and (C ₃ );
A combination of the repeating structural units (A ₁ ), (B ₁ ), (B ₂ ) and (C ₃ ), or
Combinations of the repeating structural units (A ₂ ), (B ₁ ), (B ₂ ) and (C ₃ ).
(B): In each of the combination of said (a), by substituting a part or all of _{(C 3)} to _{(C 1)} in combination.
(C): In each of the combination of said (a), by substituting a part or all of _{(C 3)} to _{(C 2)} combined.
(D): In each of the combination of said (a), by substituting a part or all of _{(C 3)} to _{(C 4)} combinations.
(E): In each of the combination of said (a), was replaced with a mixture of _{(C 3)} of some or all the _{(C 4) (C 5)} combinations.
(F): In each of the combination of said (a), by replacing part of _{(A 1)} to (A ₂₎ in combination.

  As the aromatic liquid crystal polyester, from the viewpoint of heat resistance, 30 to 80 mol% of a repeating structural unit derived from at least one compound selected from the group consisting of p-hydroxybenzoic acid and 2-hydroxy-6-naphthoic acid; 10 to 35 mol% of repeating structural units derived from at least one compound selected from the group consisting of hydroquinone and 4,4'-dihydroxybiphenyl, and derived from at least one compound selected from the group consisting of terephthalic acid and isophthalic acid It is preferable that the repeating unit is composed of 10 to 35 mol%.

  The weight average molecular weight of the aromatic liquid crystal polyester is not particularly limited, but is preferably 10,000 to 100,000.

  The method for producing the aromatic liquid crystal polyester used in the present invention is not particularly limited. For example, at least one selected from the group consisting of aromatic hydroxycarboxylic acids and aromatic diols is acylated with an excess amount of fatty acid anhydride. A method in which an acylated product is obtained, and the obtained acylated product is subjected to ester exchange (polycondensation) with at least one selected from the group consisting of an aromatic hydroxycarboxylic acid and an aromatic dicarboxylic acid to carry out melt polymerization. As the acylated product, a fatty acid ester obtained by acylation in advance may be used.

  In the acylation reaction, the amount of the fatty acid anhydride to be added is preferably 1.0 to 1.2 times equivalent to the phenolic hydroxyl group, more preferably 1.05 to 1.1 times equivalent. If the amount of the fatty acid anhydride is small, the acylated product, aromatic hydroxycarboxylic acid, aromatic dicarboxylic acid, etc., will sublimate during transesterification (polycondensation), and the reaction system tends to be clogged. The coloring of the obtained aromatic liquid crystal polyester tends to be remarkable.

  The acylation reaction is preferably performed at 130 to 180 ° C. for 5 minutes to 10 hours, more preferably at 140 to 160 ° C. for 10 minutes to 3 hours.

  The fatty acid anhydride used in the acylation reaction is not particularly limited. For example, acetic anhydride, propionic anhydride, butyric anhydride, isobutyric anhydride, valeric anhydride, pivalic anhydride, 2-ethylhexanoic anhydride, monochloroacetic anhydride Dichloroacetic anhydride, trichloroacetic anhydride, monobromoacetic anhydride, dibromoacetic anhydride, tribromoacetic anhydride, monofluoroacetic anhydride, difluoroacetic anhydride, trifluoroacetic anhydride, glutaric anhydride, maleic anhydride, succinic anhydride, β- Bromopropionic acid and the like may be mentioned, and these may be used as a mixture of two or more kinds. From the viewpoint of price and handling properties, acetic anhydride, propionic anhydride, butyric anhydride, or isobutyric anhydride is preferably used, and more preferably, acetic anhydride is used.

  In the transesterification, the acyl group of the acylated product is preferably 0.8 to 1.2 times equivalent of the carboxyl group.

  The transesterification is preferably performed at a temperature of 130 to 400 ° C. at a rate of 0.1 to 50 ° C./min, and is preferably performed at a temperature of 150 to 350 ° C. at a rate of 0.3 to 5 ° C./min. Is more preferable.

  When transesterifying a fatty acid ester obtained by acylation with a carboxylic acid, in order to shift the equilibrium, it is preferable to distill off by-produced fatty acid and unreacted fatty acid anhydride to the outside by evaporating or the like. .

  The acylation reaction and transesterification may be performed in the presence of a catalyst. As the catalyst, those conventionally known as catalysts for polyester polymerization can be used, for example, magnesium acetate, stannous acetate, tetrabutyl titanate, lead acetate, sodium acetate, potassium acetate, antimony trioxide and the like. And organic compound catalysts such as N, N-dimethylaminopyridine and N-methylimidazole. The catalyst is usually charged when the monomers are charged, and it is not always necessary to remove the catalyst even after the acylation. If the catalyst is not removed, the transesterification can be performed as it is.

Polycondensation by transesterification is usually performed by melt polymerization, but melt polymerization and solid phase polymerization may be used in combination. The solid phase polymerization is preferably performed by a known solid phase polymerization method after extracting the polymer from the melt polymerization step and then pulverizing the polymer into powder or flake. Specifically, for example, a method in which heat treatment is performed in a solid state at 20 to 350 ° C. for 1 to 30 hours in an inert atmosphere such as nitrogen. The solid-phase polymerization may be performed with or without stirring. By providing a suitable stirring mechanism, the melt polymerization tank and the solid phase polymerization tank can be the same reaction tank. After the solid phase polymerization, the obtained aromatic liquid crystal polyester may be pelletized and molded by a known method.
The production of the aromatic liquid crystal polyester can be performed using, for example, a batch apparatus, a continuous apparatus, or the like.

式中、Ａはハロゲン原子またはトリハロゲン化メチル基を表わし、ｉはＡの個数であって１〜５の整数を表わす。ｉが２以上の場合、複数あるＡは互いに同一でも異なっていてもよいが、同一であることが好ましい。
ｉは好ましくは１〜３であり、より好ましくは１または２である。ｉが１のときのＡの置換位置は４位であることが好ましく、ｉが２以上のとき少なくとも一つのＡの置換位置は４位であることが好ましい（水酸基の置換位置を１位とする）。 In the present invention, the solvent used to obtain the aromatic liquid crystal polyester solution composition is a solvent containing a halogen-substituted phenol compound represented by the following general formula (I). The solvent is preferably a solvent containing 30% by weight or more of the phenol compound, more preferably a solvent containing 60% by weight or more of the phenol compound, and substantially 100% by weight of the phenol compound. Use as a solvent is more preferred because it is not necessary to mix it with other components.

In the formula, A represents a halogen atom or a methyl trihalide group, i represents the number of A and represents an integer of 1 to 5. When i is 2 or more, a plurality of A may be the same or different from each other, but are preferably the same.
i is preferably 1 to 3, and more preferably 1 or 2. When i is 1, the substitution position of A is preferably 4-position, and when i is 2 or more, at least one substitution position of A is preferably 4-position (the substitution position of the hydroxyl group is 1-position). ).

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A fluorine atom or a chlorine atom is preferable, and a chlorine atom is particularly preferable.
Examples of the halogen-substituted phenol compound represented by the general formula (I) in which a halogen atom is a fluorine atom include pentafluorophenol, tetrafluorophenol and the like.
Examples of the halogen-substituted phenol compound represented by the general formula (I) in which the halogen atom is a chlorine atom include o-chlorophenol and p-chlorophenol, and p-chlorophenol is preferred from the viewpoint of solubility.

Examples of the halogen of the trihalogenated methyl group include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
Examples of the halogen-substituted phenol compound represented by the general formula (I) in which the halogen of the methyl trihalide group is a fluorine atom include 3,5-bistrifluoromethylphenol.

  As the halogen-substituted phenol compound represented by the general formula (I), a chlorine-substituted phenol compound such as o-chlorophenol and p-chlorophenol is preferably used from the viewpoint of price and availability, and from the viewpoint of solubility, -Chlorophenol is more preferably used.

The solvent may contain other components in addition to the halogen-substituted phenol compound as long as the aromatic liquid crystal polyester is not precipitated during storage of the solution or during casting described below.
The other components that may be contained are not particularly limited, and include, for example, chlorine compounds such as chloroform, methylene chloride, and tetrachloroethane.

The aromatic liquid crystal polyester solution composition of the present invention is obtained by dissolving 0.5 to 100 parts by weight of the aromatic liquid crystal polyester in 100 parts by weight of the solvent.
From the viewpoint of workability or economy, the amount of the aromatic liquid crystal polyester is preferably 1 to 50 parts by weight, and more preferably 5 to 15 parts by weight based on 100 parts by weight of the solvent. More preferably, there is. If the amount is small, the production efficiency tends to decrease, and if too large, the dissolution tends to be difficult.

  In the present invention, the aromatic liquid crystal polyester is dissolved in the solvent at a higher temperature. Even if the solution thus obtained is cooled to room temperature, it has a lower viscosity and is easily cast uniformly, so that a film having a good surface condition can be obtained. However, if the temperature at which the aromatic liquid crystal polyester is dissolved in the solvent is too high, the film tends to be brittle and the film cannot be formed. In the present invention, the temperature at which the aromatic liquid crystal polyester is dissolved in the solvent is higher than 120 ° C and lower than 160 ° C, preferably 125 ° C or higher and 155 ° C or lower, and more preferably 130 ° C or higher and 150 ° C or lower. More preferred.

  It is preferable that the aromatic liquid crystal polyester solution composition be filtered, if necessary, with a filter or the like to remove fine foreign substances contained in the solution composition.

  In addition, the aromatic liquid crystal polyester solution composition may include an inorganic filler such as silica, aluminum hydroxide, and calcium carbonate, a cured epoxy resin, a crosslinked benzoguanamine resin, and a crosslinked acrylic polymer, as long as the object of the present invention is not impaired. Filler, polyamide, polyester, polyphenylene sulfide, polyether ketone, polycarbonate, polyether sulfone, polyphenyl ether and modified products thereof, thermoplastic resins such as polyetherimide, heat of phenol resin, epoxy resin, polyimide resin, cyanate resin, etc. One or more kinds of various additives such as a curable resin, a silane coupling agent, an antioxidant, and an ultraviolet absorber may be added.

  As a method for obtaining an aromatic liquid crystal polyester film from the aromatic liquid crystal polyester solution composition of the present invention, the aromatic liquid crystal polyester solution composition is cast on a substrate having a smooth surface such as glass or metal, and the solvent is removed. And the like.

  The method for removing the solvent is not particularly limited, but is preferably performed by evaporating the solvent. Examples of the method for evaporating the solvent include methods such as heating, reduced pressure, and ventilation.

  The obtained aromatic liquid crystal polyester film may be further subjected to a heat treatment, if necessary.

  The aromatic liquid crystal polyester film thus obtained has excellent tear strength in the direction perpendicular to the flow direction during molding, and has excellent properties such as low moisture absorption and high frequency characteristics of the aromatic liquid crystal polyester, Because the surface condition is good, it can be used as a base for multi-layer printed boards for semiconductor packages and motherboards, flexible printed wiring boards, tape-automated bonding films, and other 8 mm video tapes obtained by the build-up method, which has attracted attention in recent years. Materials, commercial digital video tape base materials, transparent conductive (ITO) film base materials, polarizing film base materials, various cooked foods, microwave oven heating packaging films, electromagnetic wave shielding films, antibacterial films, It can be suitably used for a gas separation film and the like.

  Hereinafter, the present invention will be described based on examples, but it goes without saying that the present invention is not limited to the examples.

Example 1
In a reactor equipped with a stirrer, a torque meter, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 141 g (1.02 mol) of p-hydroxybenzoic acid and 63.3 g (0.4 g of 4,4′-dihydroxybiphenyl) were added. 34 mol), 56.5 g (0.34 mol) of isophthalic acid and 191 g (1.87 mol) of acetic anhydride. After sufficiently replacing the inside of the reactor with nitrogen gas, the temperature was raised to 150 ° C. over 15 minutes under a nitrogen gas stream, and the temperature was maintained at reflux for 3 hours.
Thereafter, the temperature was raised to 320 ° C. over 170 minutes while distilling off distilling by-product acetic acid and unreacted acetic anhydride, and the point at which a rise in torque was recognized was regarded as the end of the reaction, and the contents were taken out. The obtained solid content was cooled to room temperature, pulverized by a coarse pulverizer, kept at 250 ° C. for 3 hours in a nitrogen atmosphere, and proceeded with a polymerization reaction in a solid layer to obtain an aromatic liquid crystal polyester powder. In the obtained powder, a schlieren pattern specific to the liquid crystal phase was observed at 350 ° C. by a deflection microscope.

  0.4 g of the obtained aromatic liquid crystalline polyester powder was compression-molded under a load of 100 kg at 250 ° C. for 10 minutes using a flow tester CFT-500 manufactured by Shimadzu Corporation and a disk-shaped test piece having a thickness of 3 mm. Got. Using this test piece, the water absorption at 85 ° C./85% RH for 168 hours was measured using a constant temperature and humidity apparatus ADVANTEC AGX manufactured by Toyo Seisakusho. As a result, it was confirmed that the water absorption was 0.1% or less. . The dielectric loss tangent was measured using a Hewlett-Packard HP impedance analyzer, and was found to be 0.004 (1 GHz).

  1.0 g of the aromatic liquid crystal polyester powder obtained in the above step was added to 9.0 g of the halogen-substituted phenol compound (p-chlorophenol), and the mixture was dissolved at 140 ° C. for 8 hours. It was confirmed that a solution was obtained. Furthermore, when the solution viscosity was measured using a Tokimec B-type viscometer, the solution viscosity was 170 poise (25 ° C.). Table 1 shows the relationship between the dissolution temperature, the solution viscosity, and the film forming property. The solution was cast on a glass plate, the solvent was evaporated at a set temperature of 100 ° C. for 1 hour using a hot plate, and heat treatment was performed at 250 ° C. for 1 hour using a hot air dryer. As a result, a 25 μm thick fragrance was obtained. A group III liquid crystal polyester film was obtained. When the solution was cast on a glass plate, the solution was excellent in castability and good in film-forming properties. Further, the orientation pattern of the obtained aromatic liquid crystal polyester film was measured with a MOA-5012 simple molecular orientation meter manufactured by Oji Scientific Instruments. As a result, it was confirmed that the ratio between the longitudinal direction and the transverse direction was 1 and there was no anisotropy. did.

Example 2
1.0 g of the aromatic liquid crystal polyester powder obtained in Example 1 was added to 9.0 g of a halogen-substituted phenol compound (p-chlorophenol), and dissolved at 130 ° C. for 8 hours. It was confirmed that a suitable solution was obtained. When the solution viscosity was measured using a Tokimec B-type viscometer, the solution viscosity was 520 poise (25 ° C.). The solution was cast on a glass plate, the solvent was evaporated at a set temperature of 100 ° C. for 1 hour using a hot plate, and heat treatment was performed at 250 ° C. for 1 hour using a hot air dryer. A group III liquid crystal polyester film was obtained. When the solution was cast on a glass plate, the solution was excellent in castability and good in film-forming properties.

Example 3
1.0 g of the aromatic liquid crystal polyester powder obtained in Example 1 was added to 9.0 g of a halogen-substituted phenol compound (p-chlorophenol), and dissolved at 150 ° C. for 8 hours. It was confirmed that a suitable solution was obtained. When the solution viscosity was measured using a Tokimec B-type viscometer, the solution viscosity was 110 poise (25 ° C.). The solution was cast on a glass plate, the solvent was evaporated at a set temperature of 100 ° C. for 1 hour using a hot plate, and heat treatment was performed at 250 ° C. for 1 hour using a hot air dryer. A group III liquid crystal polyester film was obtained. When the solution was cast on a glass plate, the solution was excellent in castability and good in film-forming properties.

Comparative Example 1
1.0 g of the aromatic liquid crystal polyester powder obtained in Example 1 was added to 9.0 g of a halogen-substituted phenol compound (p-chlorophenol), and the mixture was dissolved at 120 ° C. for 8 hours. It was confirmed that a suitable solution was obtained. When the solution viscosity was measured using a Tokimec B-type viscometer, the solution viscosity was 780 poise (25 ° C.). When the solution was cast on a glass plate, the solution viscosity was high and the castability was poor. The solvent was evaporated at a set temperature of 100 ° C. for 1 hour using a hot plate, and heat treatment was further performed at 250 ° C. for 1 hour using a hot-air dryer. As a result, an aromatic liquid crystal polyester film having a thickness of 25 μm was obtained. Irregularities and irregularities were observed on the surface, and the surface condition was poor.

Comparative Example 2
1.0 g of the aromatic liquid crystal polyester powder obtained in Example 1 was added to 9.0 g of the halogen-substituted phenol compound (p-chlorophenol), and dissolved at 160 ° C. for 8 hours. It was confirmed that a suitable solution was obtained. When the solution viscosity was measured using a Tokimec B-type viscometer, the solution viscosity was 30 poise (25 ° C.). This solution was cast on a glass plate, the solvent was evaporated at a set temperature of 100 ° C. for 1 hour using a hot plate, and heat treatment was further performed at 250 ° C. for 1 hour using a hot air dryer. Was brittle and could not be obtained in the form of a film.

芳香族液晶ポリエステル溶解量＝１０重量％
製膜性： ○：良好、 ×：悪い
表面状態： ○：良好、 ×：厚み斑や凹凸が見られる

Dissolved amount of aromatic liquid crystal polyester = 10% by weight
Film forming property: ：: good, ×: bad Surface condition: ：: good, ×: unevenness of thickness and unevenness are observed

Claims (3)

An aromatic liquid crystal polyester solution composition obtained by dissolving 0.5 to 100 parts by weight of an aromatic liquid crystal polyester at a temperature higher than 120 ° C and lower than 160 ° C with respect to 100 parts by weight of the following solvent.
Solvent: A solvent containing a halogen-substituted phenol compound represented by the following general formula (I).

(Wherein, A represents a halogen atom or a trihalogenated methyl group, i represents the number of A and represents an integer of 1 to 5, and when i is 2 or more, a plurality of As are the same or different. May be.)   The solution composition according to claim 1, which is obtained by dissolving at a temperature of 125 ° C to 155 ° C. The solution composition according to claim 1, which is obtained by dissolving at a temperature of 130C to 150C.