JPH06298916A - Aromatic polyester and its production - Google Patents

Abstract

PURPOSE:To provide a new aromatic polyester excellent in mechanical properties and thermal resistance and useful preferably in the fields of electricity, electronic materials, automotive materials, etc. CONSTITUTION:There is provided a polyester composed of repeating units represented by formulae I to IV (X is formula V; Y is formula VI). The ratio of formula I is 50 to 75mol% based on the total amount of formulae I to VI and the ratio of formula II is 6 to 50mol% based on the total amount of formulae II and III. The total amount of formulae II and III is substantially equal to formula IV. This polyester exhibits 260 to 370 deg.C flow temperature defined by the temperature where the polymer heated and melted at 4 deg.C/min exhibits 48000 poise melting viscosity when extruded through a nozzle of 1mm inner diamenter and 10mmm length under 100kg/cm<2> load. Production of this polymer is carried out by copolymerization of acetoxybenzoic acid of formula VII (Ac is acetyl), 9,10-dihydroxypenanthrene-2,7-dicarboxylic acid of formula VIII, an aromatic dicarboxylic acid of formula IX (X is a dicalent aromatic group) and an acetylated aromatic diol of formula X (Y is a divalent aromatic group).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel aromatic polyester and a method for producing the same. More specifically, the present invention relates to an aromatic liquid crystal polyester preferably used in the fields of electricity, electronic materials, automobile materials and the like, and a method for producing the same.

[0002]

2. Description of the Related Art Recent technological advances in various fields such as electric and electronic materials and automobile materials are remarkable, and polymer materials used in these new fields require high performance such as high strength and high heat resistance. Has been done. In particular, electronic parts such as relay parts, coil bobbins, and connectors are becoming smaller and thinner, and high performance such as high dimensional accuracy, high strength, high rigidity, and excellent thin-wall fluidity is required. As a polymer material that satisfies the performance of
Aromatic liquid crystal polyesters are preferably used. Among the liquid crystal polyesters, particularly the melt liquid crystal polyester has excellent thin-wall moldability and is rapidly becoming popular as an electronic component material.

The molten liquid crystalline polyester includes a liquid crystalline polyester whose main chain is a wholly aromatic hydrocarbon (hereinafter sometimes referred to as an aromatic liquid crystalline polyester) and a liquid crystal polyester containing an aliphatic hydrocarbon in its main chain (hereinafter referred to as an aromatic liquid crystalline polyester). Sometimes called liquid crystal polyester containing aliphatic). Aromatic liquid crystal polyester has a parahydroxybenzoic acid unit as a main component, and a crankshaft structure such as a naphthalene skeleton is introduced into the main chain as a copolymerization component (USP40
67852), a bending structure such as isophthalic acid is introduced into the main chain [Mol. Cryst. Liq. Cryst. 169, 23 (1989)] to lower the liquid crystal transition temperature and lower the molding temperature. However, if the amount of such a copolymerization component is too small, the effect of lowering the molding temperature is small, and if it is too high, the molding temperature can be lowered, but the heat resistance is further lowered.

As the liquid crystal polyester containing an aliphatic compound, for example, a copolymer of polyethylene terephthalate and para-hydroxybenzoic acid (USP3338410)
It is known that the inclusion of aliphatic compounds greatly reduces the heat resistance, and the usable applications are greatly limited. 9,10-corresponding to one component of the aromatic liquid crystal polyester of the present invention
An aromatic polyester obtained by copolymerizing dihydrophenanthrene-2,7-dicarboxylic acid, an aliphatic diol and a dihydric phenol is described in JP-A-4-146920, but the melting point is described therein. However, there is no description about heat resistance, and it is considered that the heat resistance is low like the copolymer of polyethylene phthalate and parahydroxybenzoic acid.

[0005]

SUMMARY OF THE INVENTION The present invention provides an aromatic polyester having excellent mechanical properties and heat resistance and improved moldability, and a method for producing the same.

[0006]

As a result of continuing intensive studies, the present inventors have surprisingly found that by co-polymerizing 9,10-dihydrophenanthrene-2,7-dicarboxylic acid, a fragrance can be obtained. They have found that they have the effect of lowering the liquid crystal transition temperature of group polyesters, and have completed the present invention. That is, the present invention is as follows. [1] consists of the following repeating units (1), (2), (3) and (4), wherein repeating unit (1) is repeating unit (1),
50 to 75 mol% of the sum of (2), (3) and (4), 6 to 50 mol% of the repeating unit (2) to 6 to 50 mol% of the sum of the repeating units (2) and (3), The sum of (2) and (3) is substantially equal to repeating unit (4),

[Chemical 9]

[Chemical 10]

[Chemical 11] (In the formula, X is a divalent aromatic group.) —O—Y—O— (4) (In the formula, Y is a divalent aromatic group.) The flow temperature defined below is An aromatic liquid crystal polyester having a temperature of 260 ° C. or higher and 370 ° C. or lower. Flow temperature: Polymer melted by heating at a heating rate of 4 ° C./min., Load of 100 kg / cm ² , inner diameter of 1 mm, length of 10 m.
When extruded from a nozzle of m, the melt viscosity is 4800.
It is the temperature at the point of 0 poise.

[2] The aromatic liquid crystal polyester according to [1], wherein X has a repeating unit (3) which is at least one group selected from the following group (A) of groups.

[Chemical 12]

[3] The aromatic liquid crystal polyester according to [1], wherein Y has a repeating unit (4) which is at least one group selected from the following group (B) of groups.

[Chemical 13]

[4] Acetoxybenzoic acid represented by the following general formula (5), 9,10-dihydrophenanthrene-2,7-dicarboxylic acid represented by the general formula (6), and general formula ( The method for producing an aromatic liquid crystal polyester according to [1], which comprises copolymerizing an aromatic dicarboxylic acid represented by 7) with a diacetylated product of an aromatic diol represented by the general formula (8).

[Chemical 14] (In the formula, Ac is an acetyl group.)

[Chemical 15]

[Chemical 16] (In the formula, X is a divalent aromatic group.) A _C O-Y-OA _C (8) (In the formula, Y is a divalent aromatic group and A _C is an acetyl group. )

The present invention will be described in detail below. The repeating unit (1) of the aromatic liquid crystal polyester of the present invention is represented by the following formula.

[Chemical 17]

Repeating unit (2) is a 9,10-dihydroxyphenanthrene-2,7-dicarboxylic acid residue,
It is expressed by the following formula.

[Chemical 18]

The repeating unit (3) is an aromatic dicarboxylic acid residue and is represented by the following formula.

[Chemical 19] (In the formula, X is a divalent aromatic group.) Specific examples of the divalent aromatic group X include groups shown in the following group (A).

[Chemical 20] The following groups are preferred.

[Chemical 21] The repeating unit (3) is one kind or two or more kinds having X selected from the group consisting of these.

The repeating unit (4) is an aromatic diol residue and is represented by the following formula. —O—Y—O— (4) (In the formula, Y is a divalent aromatic group.) Specific examples of the divalent aromatic group Y include groups shown in the following group (B). Can be mentioned.

[Chemical formula 22] The following groups are preferred.

[Chemical formula 23] The repeating unit (4) is one type or two or more types having Y selected from the group consisting of these.

The composition ratio of each repeating unit is as follows. Repeating unit (1) is a repeating unit (1), (2),
It is 50 to 75 mol% of the sum of (3) and (4), preferably 55 to 65%. Repeating unit (2) is 6 to 50 mol%, preferably 10 to 30 mol% of the sum of repeating units (2) and (3). Repeating units (2) and (3)
Is substantially equal to the repeating unit (4).

The flow temperature of the aromatic liquid crystal polyester of the present invention is 260 ° C. or higher and 370 ° C. or lower, and preferably 2
80 ° C or higher and 350 ° C or lower, more preferably 290
It is in the range of ℃ to 330 ℃. Flow temperature is 260 ℃
If it is less than 1, the mechanical strength of the molded product is low because the molecular weight is not sufficiently high, and if the flow temperature exceeds 370 ° C., the molding process becomes difficult, which is not preferable.

Next, the method for producing the aromatic liquid crystal polyester in the present invention will be described. The aromatic liquid crystal polyester of the present invention comprises acetoxybenzoic acid represented by the following general formula (5) and 9,10-dihydrophenanthrene-2,7-dicarboxylic acid represented by the general formula (6). Can be produced by copolymerizing an aromatic dicarboxylic acid represented by the general formula (7) and a diacetylated product of an aromatic diol represented by the general formula (8) (hereinafter, sometimes referred to as an acetylation method. .).

[Chemical formula 24] (In the formula, Ac is an acetyl group.)

[Chemical 25]

[Chemical formula 26] (In the formula, X is a divalent aromatic group.) A _C O-Y-OA _C (8) (In the formula, Y is a divalent aromatic group and A _C is an acetyl group. )

Specific examples of the aromatic dicarboxylic acid represented by the general formula (7) include the following.

[Chemical 27]

Specific examples of the diacetylated aromatic diol represented by the general formula (8) include the following.

[Chemical 28]

The polymerization is preferably 200 ° C to 400 ° C,
More preferably, it is carried out in the temperature range of 260 ° C to 370 ° C. Here, the diacetylated product of an aromatic diol may be one which is synthesized from an aromatic diol and acetic anhydride or acetyl chloride before the polymerization and isolated, or may be used as it is for the polymerization without isolation. . Further, a polymerization method such as a phenyl esterification method using a phenyl ester instead of an acetylated product of an aromatic diol, or an acid chloride method using an acid chloride of an aromatic dicarboxylic acid instead of an aromatic dicarboxylic acid may be used. It can be manufactured. In the production method of the present invention, a high boiling point solvent may be used to perform polymerization in the presence of a solvent. Polymerization
It is possible under normal pressure or reduced pressure. When the polymerization is carried out under normal pressure, the flow temperature can be adjusted within the range of 260 ° C. to 370 ° C. by pulverizing the obtained polymer after producing the prepolymer by melt polymerization and further subjecting it to solid phase polymerization.

In the production method of the present invention, it is not necessary to add a catalyst, but a catalyst may be added in order to accelerate the polymerization reaction. Known as such catalysts are salts and oxides of metals of Group 2, Group 4 or Group 5 of the periodic table. Specific examples of the polymerization catalyst include calcium acetate, titanium tetraisopropoxide, manganese acetate, tetraphenylgermanium, diethyltin, antimony oxide,
Tetramethyl lead and the like are added, and the addition amount of these catalysts is generally about 0.01 to 1.0 based on the total weight of the monomers.
%, Preferably about 0.2 to 0.5% by weight.

In the aromatic liquid crystal polyester of the present invention, other kinds of thermoplastic resins, stabilizers, antioxidants, fillers such as talc, or reinforcing materials such as glass fibers, carbon fibers, asbestos, etc. may be added, if necessary. You may mix.

[0022]

EXAMPLES The present invention will be specifically described below with reference to examples.
However, the present invention is not limited to these.
Yes. First, the measuring method used in the examples will be described. (1) Flow temperature: Flow tester manufactured by Shimadzu Corporation
Measured with a CFT-500 model and heated at a rate of 4 ° C / min.
Load heat-melted polymer 100 kg / cm ²At inner diameter
When extruding from a 1 mm, 10 mm long nozzle,
The temperature at the point where the melt viscosity shows 48,000 poise.
It (2) Optical anisotropy: Optical anisotropy of resin in molten state
Polarizes a powdered polymer placed on a heating stage
The temperature was raised at a rate of 10 ° C./min. Note that
If it does not completely melt under static conditions, use spring pressure.
It was carried out under pressure.

(3) Method for measuring molecular weight by gel permeation chromatography (GPC) method: HLC-8020 manufactured by Tosoh Corporation, column size 7.
8mm ID x 30cm, mobile phase 2,3,5,6-
Mixed solution of tetrafluorophenol (TFP) and chloroform (volume ratio TFP / CHCl ₃ = 1 / 2.7)
21) was used. Dissolve 1 mg of sample in 5 ml of TFP,
After diluting this twice with chloroform, pore size 0.4
It measured by pre-filtering with a 5-micrometer filter. The molecular weight calculation was performed using a calibration curve based on standard polystyrene. (4) Mechanical properties: Tensile strength and elastic modulus were measured according to ASTM D-638 on a test piece obtained by injection molding a polymer using a small injection molding machine manufactured by Shinko Selvik. (5) Dynamic viscoelasticity measurement: Dynamic viscoelasticity was measured using a dynamic analyzer RDAII manufactured by Rheometrics. As the measuring jig, a torsion rectangular measuring jig is used, the frequency is 10 Hz, and the measuring temperature range is from room temperature to 350.
It was ℃.

Reference Example The production of 9,10-dihydrophenanthrene-2,7-dicarboxylic acid used as a raw material in the present invention was 9,10-
Obtained by hydrolyzing the diethyl ester of dihydrophenanthrene-2,7-dicarboxylic acid with KOH in water / ethanol. A method for producing a diethyl ester of 9,10-dihydrophenanthrene-2,7-dicarboxylic acid is described in JP-A-4-169555.

Example 1 13.50 g (75 g) of p-acetoxybenzoic acid was added to a 4-neck round bottom flask equipped with a stirrer, a cooling device and a nitrogen inlet tube.
mmol), 9,10-dihydrophenanthrene-2,7-
Dicarboxylic acid 1.34 g (5 mmol), terephthalic acid 3.32 g (20 m
mol), 4,4'-diacetoxydiphenyl 6.75g (25mmo
l) is heated under a nitrogen atmosphere and gradually heated while removing acetic acid resulting from the reaction out of the system.
Reacted for hours.

The polymer obtained had a flow temperature of 268 ° C. Further, the polymer was finely pulverized by a sample mill SK-M10R type manufactured by Kyoritsu Riko Co., Ltd., and then the polymer was put into a stainless steel container and gradually heated under a nitrogen stream to carry out solid phase polymerization. After holding at the final temperature of 300 ℃ for 3 hours,
The sample was gradually cooled and then taken out. The polymer after solid-phase polymerization exhibits liquid crystallinity when melted, its flow temperature is 303 ° C., and the number average molecular weight (M
n) was 238,000. Furthermore, the polymer was molded using the polymer and the mechanical properties were measured.The tensile strength was 1100 kg.
/ cm ² , The tensile elastic modulus was 67,000 kg / cm ² . Further, FIG. 1 shows the measurement results of dynamic viscoelasticity measured by using the obtained polymer injection-molded test pieces. From room temperature to about 28
It can be seen that it has a high elastic modulus of 2.0 × 10 ⁹ dyn / cm ² or more in a wide range up to 0 ° C. and has excellent heat resistance.

Example 2 In the same four-necked round bottom flask as in Example 1, 13.50 g (75 mmol) of p-acetoxybenzoic acid and 0.67 g (2.5 mmol of 2.5,9-dihydrophenanthrene-2,7-dicarboxylic acid) were added. ), 3.74 g (22.5 mmol) of terephthalic acid and 6.75 g (25 mmol) of 4,4′-diacetoxydiphenyl are heated under a nitrogen atmosphere and gradually heated while removing acetic acid resulting from the reaction out of the system. The reaction was carried out at a temperature of 350 ° C for 2 hours. The polymer obtained had a flow temperature of 248 ° C. Further, the polymer was finely pulverized by a sample mill SK-M10R type manufactured by Kyoritsu Riko Co., Ltd., and then the polymer was put into a stainless steel container and gradually heated under a nitrogen stream to carry out solid phase polymerization. Final temperature
After holding at 300 ° C. for 3 hours, the sample was gradually cooled and then taken out. The polymer after solid phase polymerization exhibited liquid crystallinity when melted, its flow temperature was 324 ° C., and the number average molecular weight (Mn) determined by GPC was 51200. Furthermore, the polymer was molded using the polymer and the mechanical properties were measured.The tensile strength was 1020 kg / cm ² , and the tensile elastic modulus was 62000 k.
It was g / cm ² .

Comparative Example 1 A reaction was carried out in the same manner as in Example 1 except that 4.15 g (25 mmol) of terephthalic acid was used instead of 9,10-dihydrophenanthrene-2,7-dicarboxylic acid. The polymer obtained had a flow temperature of 286 ° C. Further, the polymer was finely pulverized by a sample mill SK-M10R type manufactured by Kyoritsu Riko Co., Ltd., and then the polymer was put into a stainless steel container and gradually heated under a nitrogen stream to carry out solid phase polymerization. Final temperature 30
After holding at 0 ° C. for 3 hours, the sample was gradually cooled and then taken out. The polymer after solid phase polymerization exhibited liquid crystallinity when melted, its flow temperature was 336 ° C., and the number average molecular weight (Mn) determined by GPC was 61300. Further, the polymer was molded using the polymer and the mechanical properties were measured. As a result, the tensile strength was 1230 kg / cm ² , and the tensile elastic modulus was 95000 kg / cm ² .

Comparative Example 2 In the same 4-neck round bottom flask as in Example 1, 13.50 g (75 mmol) of p-acetoxybenzoic acid and 0.34 g (1.25 mmol) of 9,10-dihydrophenanthrene-2,7-dicarboxylic acid were added. ), Terephthalic acid 3.94 g (23.75 mmol) and 4,4′-diacetoxydiphenyl 6.75 g (25 mmol) are heated under a nitrogen atmosphere,
The reaction mixture was gradually heated while removing acetic acid resulting from the reaction to the outside of the system, and reacted at a final temperature of 350 ° C for 2 hours. The polymer obtained had a flow temperature of 254 ° C. Further, the polymer was finely pulverized with a sample mill SK-M10R type manufactured by Kyoritsu Riko Co., Ltd., and then the polymer was placed in a stainless steel container and gradually heated under a nitrogen stream to perform solid phase polymerization. Final temperature
After holding at 300 ° C. for 3 hours, the sample was gradually cooled and then taken out. The polymer after the solid phase polymerization exhibited liquid crystallinity when melted, but its flowing temperature was 337 ° C., which is almost the same as that of Comparative Example 1, so it can be seen that there was no effect of lowering the molding temperature. Number average molecular weight (M
n) was 62500. Furthermore, the polymer was molded using the polymer and the mechanical properties were measured.The tensile strength was 1130 kg.
/ cm ^2, and tensile modulus = 72000kg / cm ^2.

[0030]

The aromatic liquid crystal polyester of the present invention has excellent mechanical properties and heat resistance and is easily melt-molded due to the lowered liquid crystal transition temperature. Therefore, excellent molded products, sheets, films and It is useful as a material for fibers and the like.

[Brief description of drawings]

FIG. 1 is a diagram showing a relationship between dynamic viscoelasticity and temperature measured by using an injection molded test piece of a polymer obtained in Example 1.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuki Murase, 6 Kitahara, Tsukuba, Ibaraki Prefecture, Sumitomo Chemical Co., Ltd. (72) Inventor, Kunihisa Sato, 6 Kitahara, Tsukuba, Ibaraki, Sumitomo Chemical Co., Ltd.

Claims (4)

[Claims] 1. The following repeating units (1), (2), (3) and (4), wherein the repeating unit (1) is a repeating unit (1),
50 to 75 mol% of the sum of (2), (3) and (4), 6 to 50 mol% of the repeating unit (2) to 6 to 50 mol% of the sum of the repeating units (2) and (3), The sum of (2) and (3) is substantially equal to repeating unit (4), [Chemical 2] [Chemical 3] (In the formula, X is a divalent aromatic group.) —O—Y—O— (4) (In the formula, Y is a divalent aromatic group.) The flow temperature defined below is An aromatic liquid crystal polyester having a temperature of 260 ° C. or higher and 370 ° C. or lower. Flow temperature: Polymer melted by heating at a heating rate of 4 ° C./min., Load of 100 kg / cm ² , inner diameter of 1 mm, length of 10 m.
When extruded from a nozzle of m, the melt viscosity is 4800.
It is the temperature at the point of 0 poise. 2. The aromatic liquid crystal polyester according to claim 1, wherein X has a repeating unit (3) which is at least one group selected from the following group (A) of groups. [Chemical 4] 3. The aromatic liquid crystal polyester according to claim 1, wherein Y has a repeating unit (4) which is at least one group selected from the following group (B) of groups. [Chemical 5] 4. An acetoxybenzoic acid represented by the following general formula (5), a 9,10-dihydrophenanthrene-2,7-dicarboxylic acid represented by the general formula (6), and a general formula (7). ) And an aromatic dicarboxylic acid represented by the general formula (8)
The method for producing an aromatic liquid crystal polyester according to claim 1, which comprises copolymerizing a diacetylated aromatic diol represented by: [Chemical 6] (In the formula, Ac is an acetyl group.) [Chemical 8] (In the formula, X is a divalent aromatic group.) A _C O-Y-OA _C (8) (In the formula, Y is a divalent aromatic group and A _C is an acetyl group. )