JP3306445B2 - Thermoplastic resin 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 novel thermoplastic resin composition which can be used for molded articles by injection molding or extrusion molding.

[0002]

2. Description of the Related Art Polyphenylene ether is a resin having excellent properties such as heat resistance, hot water resistance, dimensional stability, and mechanical and electrical properties. However, it has disadvantages such as poor chemical resistance, low thermal shock resistance, and the inability to form a thin wall.

As an attempt to improve the processability of polyphenylene ether, there is known a method of blending polyphenylene ether with polystyrene. However, although the processability of polyphenylene ether is improved by this method, there is a problem that the heat resistance of polyphenylene ether is reduced.

On the other hand, liquid crystal polyesters are different from crystalline polyesters such as polyethylene terephthalate and polybutylene terephthalate, in that the molecules are rigid, so that they do not entangle even in a molten state, form polydomains having a liquid crystal state, and have 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, 0.2-0.5 mm
A molded article having a small thickness can be easily obtained, and this molded article has an advantage of exhibiting high strength and high rigidity. However, there is a drawback that the anisotropy is extremely large, so that the dimensional stability of the molded product is poor and the weld strength is extremely low. In addition, applications are limited due to high molding temperature. Another problem is that liquid crystal polyesters are generally expensive.

The superior dimensional stability, mechanical properties, heat resistance, and low cost of polyphenylene ether and the excellent moldability, thin physical properties, heat resistance, mechanical properties, etc. of liquid crystal polyesters, respectively. Resin compositions utilizing the characteristics of the above resins have been strongly demanded from the market.

For example, Japanese Patent Publication No. 3-45107 discloses that a liquid crystalline polyester is blended with a polymer such as polyphenylene ether and the melt viscosity of the polymer is reduced to improve the moldability. . Also,
Japanese Patent Application Laid-Open No. 2-97555 discloses a liquid crystal polyester mixed with various polyarylene oxides for the purpose of improving solder heat resistance.

[0007]

However, in general, a composition obtained by blending a liquid crystal polyester or the like with polyphenylene ether having extremely poor moldability is not greatly improved in moldability, or the composition is difficult to mold. Even though the properties were improved, the molding of a thin-walled molded product was not achieved. In addition, since a liquid crystal polyester having a high molding temperature is compounded, the molding temperature is increased, and there is a problem that the appearance of the molded product is poor due to thermal decomposition of the compounded resin during molding. Further, there is a problem that the mechanical properties, heat resistance and the like of the composition are insufficient.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to solve these problems, and as a result, have arrived at the present invention. That is, the present invention provides the following inventions
Is what you do. (A) The following structural unit (1) (Wherein R 1 and R 2 are each independently selected from hydrogen and a hydrocarbon group having 1 to 20 carbon atoms.) In a polyphenylene ether having a number average degree of polymerization of 20 to 1200, the number average degree of polymerization is represented by X And the ratio of 0.02 / X to 1 / X of the total of the methyl groups at the 2- and 6-positions of the phenylene group is the aminomethyl group (—CH ₂
A modified polyphenylene ether substituted with NH ₂ ) , and (B) a liquid crystalline polyester, wherein components (A) and (B)
Of the component (A) exceeds 75% by weight.
0.5% by weight or less and the component (B) is less than 25% by weight.
A thermoplastic resin composition characterized in that the amount is not less than% by weight.

Component (A) of the thermoplastic resin composition of the present invention
Is 2 of the phenylene groups in the polyphenylene ether
A modified polyphenylene ether having a structural unit in which a part of the methyl group at the 6-position and / or 6 is substituted with an aminomethyl group (—CH ₂ NH ₂ ). The structural unit substituted by the aminomethyl group may be a terminal structural unit of polyphenylene ether, or may be not at the terminal but at the middle of the main chain. In particular, a structural unit substituted with the aminomethyl group is preferable because it is easy to obtain a terminal structural unit of polyphenylene ether.

The modified polyphenylene ether of the component (A) has a number average polymerization degree X,
0.02 / X to 1/1 of the sum of the methyl groups at the 6th and 6th positions
X, preferably 0.05 / X to 1 / X is substituted with an aminomethyl group. If the aminomethyl group is less than 0.02 / X of the sum of the methyl groups at the 2- and 6-positions of the phenylene group, the heat resistance and mechanical properties are not sufficiently improved when used as a component of the resin composition. Not preferred.

As the modified polyphenylene ether of the component (A), a modified polyphenylene ether represented by the general formula (1) having a number average of 20 to 1200, more preferably 30 to 1,000 is used. When the number of structural units represented by the general formula (1) is less than 20, the glass transition point is low, and the heat resistance (mainly, the deflection temperature under load) is reduced. When the number exceeds 1,200, the melt viscosity is high and the workability is high. It is not preferable because it becomes worse. As a component of the thermoplastic resin composition of the present invention, a polyphenylene ether composed of only the structural unit represented by the general formula (1) has insufficient reactivity with a liquid crystal polyester.
A modified polyphenylene ether having a structural unit in which the methyl group at the 6th and / or 6th position is substituted with an aminomethyl group is preferable because of its high reactivity with the liquid crystal polyester.

Next, a method for producing the modified polyphenylene ether of the component (A) will be described. The method for producing the modified polyphenylene ether of the component (A) includes the following general formula (2)

[0013]

Embedded image (Wherein R ₃ , R ₄ , and R ₅ are each independently selected from hydrogen and a hydrocarbon group having 1 to 20 carbon atoms), and is polymerized using an oxidation coupling catalyst. In the method, the general formula (3)

Embedded image (Wherein Q ₁ and Q ₂ are each independently selected from hydrogen, an alkyl group having 1 to 24 carbon atoms and an aralkyl group having 7 to 24 carbon atoms, provided that both Q ₁ and Q ₂ are hydrogen. Not included, and also includes those wherein Q ₁ and Q ₂ are alkylene groups which are linked to each other to form a ring.)
A method for producing a modified polyphenylene ether, wherein polymerization is carried out in the presence of 01 to 0.2 mol and the obtained polyphenylene ether is melt-kneaded, is preferred.

More specifically, in a method for polymerizing a nucleus-substituted phenol represented by the general formula (2) using an oxidative coupling catalyst, the polymerization is carried out in the presence of an amine represented by the general formula (3). I do. The amines are used in an amount of 0.001 to 1 mol per nucleus-substituted phenol used.
0.2 mol, preferably 0.005 to 0.05 mol is present. If the use ratio is less than 0.001 mol per mol of the nucleus-substituted phenol, it is not preferable because a high-quality polyphenylene ether cannot be obtained, and if it is more than 0.2 mol, a practical molecular weight polyphenylene ether is used. Is not preferred since Thus, a polyphenylene ether having the amines in the side chain can be obtained. The nucleus-substituted phenols represented by the general formula (2) can be used alone or in combination of two or more.

Preferred nucleus-substituted phenols include 2,
6-dimethylphenol, 2,3,6-trimethylphenol and the like can be mentioned. Particularly, 2,6-dimethylphenol is preferable.

Next, as the amines represented by the general formula (3), specifically, n-propylamine, iso-propylamine, n-butylamine, iso-butylamine, sec-butylamine, n-hexylamine, n-
1 such as octylamine, 2-ethylhexylamine, cyclohexylamine, laurylamine, benzylamine, etc.
And secondary amines such as diethylamine, diethylamine, di-n-propylamine, di-n-butylamine, di-iso-butylamine, di-n-octylamine, piperidine, and 2-pipecholine. The general formula (3)
Is also equivalent to the amine represented by the general formula (3). Examples of such polyamines include ethylenediamine, piperazine, and 1,3-dipiperidylpropane. And the like.

Specifically, it is possible to use a catalyst system in which an amine represented by the general formula (3) is combined with a known copper compound, manganese compound or cobalt compound and a ligand selected from bases. preferable. For example, JP-A-53-
No. 79993, a method of oxidatively coupling a phenolic monomer with oxygen in the presence of a catalyst comprising a manganese salt, a basic reaction medium and a secondary amine, or JP-A-63-54424. As described in
A method in which a nucleus-substituted phenol is oxidatively polymerized with an oxygen-containing gas in an organic solvent in the presence of a catalyst. As a catalyst, a manganese compound containing one or more divalent manganese salts, a metal of Group IA metal of the periodic table Examples include a method using a catalyst system containing at least one basic compound selected from hydroxides, alkoxides or phenoxides, hydroxides of Group IIA metals and oxides, alkanolamines, and amines.

Thus, the following general formula (4)

Embedded image (Wherein Q ₁ and Q ₂ are each independently selected from hydrogen, an alkyl group having 1 to 24 carbon atoms and an aralkyl group having 7 to 24 carbon atoms, provided that Q ₁ and Q ₂ are both hydrogen. Not included, and also includes those in which Q ₁ and Q ₂ are alkylene groups which are linked by forming a ring.) In which the methyl group at the 2-position and / or 6-position of the phenylene group is substituted. Polyphenylene ether having the structural unit described above can be obtained.

The structural unit to which the secondary or tertiary amine is bonded may be a structural unit at the terminal of polyphenylene ether, or may be not at the terminal but at the middle of the main chain. In particular, it is preferable because it is easy to obtain a structural unit that is a terminal structural unit of polyphenylene ether.

Next, a secondary or tertiary methyl group is added to the 2- and / or 6-methyl group of the phenylene group thus obtained.
The modified polyphenylene ether of the component (A) of the liquid crystal polyester resin composition of the present invention can be obtained by melt-kneading the polyphenylene ether having the secondary amine bonded thereto.

The melt kneading is performed at a resin temperature of 200 to 300.
C, preferably at 230 to 280C. If the resin temperature is lower than 200 ° C., the molding processability of the raw material polyphenylene ether is poor, and if the resin temperature exceeds 300 ° C., decomposition of the polyphenylene ether occurs, which is not preferable. For the melt kneading, it is preferable to use a kneading apparatus generally used such as a single-screw or twin-screw extruder or various kneaders.

At the time of melt-kneading, a radical initiator may be blended for melt-kneading. Further, a radical initiator may be previously blended with the polyphenylene ether and melt-kneaded. Preferred radical initiators include cumene hydroperoxide, t
-Butyl hydroperoxide, dimethyl-2,5-
Bis (hydroperoxy) hexane, 1,3-bis (t-butylperoxyisopropyl) benzene, t-
Butyl peroxide, 2,6-di-t-butyl-4methylphenol and the like. The fact that the component (A) constituting the resin composition obtained by the above-described method is a modified polyphenylene ether containing a primary amine means that the modified polyphenylene ether or the polyphenylene ether is extracted from the composition by using a solvent and re-extracted. It can also be confirmed by sedimentation and quantification of the amine species in the extracted component by potentiometric titration or the like.

If necessary, unmodified polyphenylene ether, styrene-grafted polyphenylene ether, polystyrene and the like can be blended with the modified polyphenylene ether of the component (A) in the thermoplastic resin composition of the present invention.

Component (A) of the thermoplastic resin composition of the present invention
Modified polyphenylene ether and reduced viscosity η _{SP /} c (0.5 g / dl) of the raw material polyphenylene ether
Is measured at 25 ° C. for a chloroform solution of
The range of 0.30 to 0.65 dl / g is preferred. η _SP /
When c is less than 0.30 dl / g, the heat resistance of the composition is remarkably reduced, and when η _SP / c exceeds 0.65 dl / g, the moldability of the composition deteriorates, which is not preferable.

The liquid crystal polyester of the component (B) of the liquid crystal polyester resin composition of the present invention is a polyester called a thermotropic liquid crystal polymer. Specifically, (1) a combination of an aromatic dicarboxylic acid, an aromatic diol, and an aromatic hydroxycarboxylic acid (2) a combination of different aromatic hydroxycarboxylic acids (3) an aromatic dicarboxylic acid (4) a polyester obtained by reacting an aromatic hydroxycarboxylic acid with a polyester such as polyethylene terephthalate, which forms an anisotropic melt at a temperature of 400 ° C. or lower. Things. 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. Repeating structural unit derived from aromatic dicarboxylic acid:

[0026]

Embedded image

[0027]

Embedded image Repeating structural unit derived from aromatic diol:

[0028]

Embedded image

[0029]

Embedded image Repeating structural unit derived from aromatic hydroxycarboxylic acid:

[0030]

Embedded image A liquid crystal polyester which is particularly preferable from the balance of heat resistance, mechanical properties and processability is

[0031]

Embedded image In particular, combinations of repeating structural units include the following (I) to (V).

[0032]

Embedded image

[0033]

Embedded image

[0034]

Embedded image

[0035]

Embedded image

[0036]

Embedded image The liquid crystal polyesters (I), (II), (III),
Regarding (IV), for example, JP-B-47-4
No. 7,870, JP-B-63-3888, JP-B-63-3891, and JP-B-56-18016.

In the resin composition of the present invention comprising the components (A) and (B), the composition ratio of the components (A) and (B) takes a value within a specific range, thereby achieving the object. A thermoplastic resin composition can be obtained. In the present invention, the ratio of component (A) to component (B) is preferably more than 75% by weight and less than 99.5% by weight of component (A), and more than 0.5% by weight and less than 25% by weight of component (B). Component (A) is 75
If the amount is less than 9% by weight, the effect of cost reduction is not remarkable.

In the thermoplastic resin composition of the present invention,
If desired, an inorganic filler is used. Such inorganic fillers include calcium carbonate, talc, clay, silica, magnesium carbonate, barium sulfate, titanium oxide, alumina, gypsum, glass fiber, carbon fiber, alumina fiber,
Examples thereof include silica alumina fibers, aluminum borate whiskers, and potassium titanate fibers.

The thermoplastic resin composition of 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, an inorganic or organic coloring. Various additives such as a rust preventive, a cross-linking agent, a foaming agent, a fluorescent agent, a surface smoothing agent, a surface gloss improving agent, and a mold release improving agent such as a fluororesin are added in a manufacturing process or in a subsequent processing process. be able to.

The method for producing the thermoplastic resin composition of the present invention is not particularly limited, and a known method can be used. For example, there is a method in which the respective components are mixed in a solution state and the solvent is evaporated or precipitated in a non-solvent. 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 kneading, each component may be previously mixed uniformly with a device such as a tumbler or a Henschel mixer. be able to.

For example, modified polyphenylene ether obtained by melt-kneading once, raw material polyphenylene ether,
The resin composition can be obtained by mixing liquid crystal polyester or the like with a Henschel mixer and kneading with a kneader. Alternatively, the raw material polyphenylene ether is charged from the first feed port of the kneading machine, and the mixture is kneaded appropriately and the first kneading machine has
Between the feed port and the second feed port, two phenylene groups
A modified polyphenylene ether in which the methyl group at the 6th and / or 6th position is substituted with an aminomethyl group is prepared, and then the liquid crystal polyester is charged from the second feed port to obtain the resin composition by one kneading. it can.

The kneaded resin composition is molded by injection molding, extrusion molding, or other various molding methods, but is not subjected to a kneading process in advance, but is dry-blended at the time of injection molding or extrusion molding to perform a melt processing operation. The resin composition of the present invention can be kneaded into the resin composition to directly obtain a molded product.

[0043]

EXAMPLES The present invention will be described below with reference to examples, but these are merely examples and the present invention is not limited thereto. In addition, polyphenylene ether may be abbreviated as PPE.

(I) Method of measuring physical properties Number average molecular weight of polyphenylene ether: Determined by gel permeation chromatography (hereinafter sometimes referred to as GPC) according to a conventional method. Determination method of amine in raw material polyphenylene ether and modified polyphenylene ether: Nitrogen content in all amines: About 1 g of sample was weighed, dissolved in 50 cc of chloroform, added with 5 cc of acetic acid, and manufactured by Kyoto Electronics Co., Ltd. Potentiometric titration was performed using a potentiometric titrator AT-310 (glass-calomel electrode, titrant 0.1 mol perchloric acid, (acetic acid solution)), and the nitrogen content in all amines was determined according to the following equation. N _T = 0.0014 × A × C ₁ × 100 / S N _T : Nitrogen content of all amines (%) A: Titration (cc) S: Sample amount (g) C ₁ : Concentration of perchloric acid solution ( Mol / l)

Nitrogen content in tertiary amine: Approximately 1 g of a sample was weighed, dissolved in 50 cc of chloroform, and dissolved in acetic anhydride.
After adding cc, the mixture was allowed to stand, 5 cc of acetic acid was added, and a potentiometric titration was performed in the same manner as in the case of titration of the nitrogen content in all amines. N ₃ = 0.0014 × B × C ₂ × 100 / S N ₃ : Nitrogen content in tertiary amine (%) B: Titration (cc) S: Sample amount (g) C ₂ : Perchloric acid solution Concentration (mol / liter)

Nitrogen content in secondary amine: about 1 g of sample
Weigh and dissolve in 50 cc of chloroform, salicyl
Add 0.5 cc of aldehyde and leave it for
0.1 mol / l hydrochloric acid in 2-propanol
Potentiometric titration as in the case of total amine titration except
Is performed, and (secondary amine +
Nitrogen content N of tertiary amine) _Two,_Three(%) Was determined. N_Two,_Three= 0.014 × C × D × 100 / S C: concentration of titrated hydrochloric acid (mol / liter) D: titration (cc) S: amount of sample (g) Content N
_Two(%) Was determined. N_Two= N_Two,_Three-N_Three

Nitrogen content in primary amine: The nitrogen content N ₁ (%) of the primary amine in the sample was determined according to the following equation. _{N 1 = N T -N 2 -N} 3

Thermogravimetric analysis: The pellet-shaped sample was pulverized and fractionated with a 42 mesh filter. The powder sample was used for measurement as it was. The measurement was made by Shimadzu TGA-5.
The temperature was raised at a rate of 10 ° C./min. The main decomposition temperature was determined at the intersection of the baseline and the tangent at the point of maximum inclination of the baseline shift, and the decomposition initiation temperature was the temperature at which the weight was reduced by 2%.

Method for measuring physical properties of molded article: Physical properties were measured by kneading the composition at a cylinder temperature of 320 ° C. using a PCM-30 twin screw extruder manufactured by Ikegai Iron Works Co., Ltd., and then PS40E5ASE manufactured by Nissei Plastic Industry Co., Ltd. Using a mold injection molding machine, the injection molding was performed at a molding temperature of 320 ° C and a mold temperature of 100 ° C.

Deflection temperature under load (TDUL), tensile strength:
ASTM 4 tensile dumbbell, TDUL measurement test piece (1
(27 mm length x 12.7 mm width x 6.4 mm thickness) and molded into ASTM D638 and ASTM D648, respectively.
The tensile strength and TDUL (load 18.6 kg) were measured according to the above.

Weld part strength, non-weld part strength: Test pieces shown in FIG. 1 were molded from the composition of the present invention. This test piece had a thickness of 3 mm, an outer dimension of 64 mm, and an inner dimension of 38 mm. From this, a hatched portion (64 × 13 mm) including the weld line shown in FIG.
m, and the bending strength was measured at a bending speed of 2 mm / min. Also,
Non-weld part (64 × 13mm) from test piece of same shape
Was cut out, and the bending strength was measured in the same manner.

Molding shrinkage and anisotropy ratio: The dimensions of the injection molded article in the flow direction (MD) and the direction perpendicular to the flow (TD) were measured and determined as the ratio to the original mold size. The anisotropy ratio of the molding shrinkage was determined as the ratio (TD / MD) between the shrinkage in the TD direction and the shrinkage in the MD direction. Tensile strength of thin molded product: 0.8mm thick, 75m long
The composition was injection-molded using a mold having a width of 5 mm and a neck portion of 5 mm. Moreover, the tensile strength was measured using the obtained dumbbell test piece.

Appearance of injection-molded product and thin-walled molded product: Observation of the injection-molded product was performed on test specimens used for measurement of tensile strength, deflection temperature under load, weld strength, and non-weld strength. Since there was no difference in the results, the evaluation results are collectively shown in the column of the injection molded product in Table 1. The observation of the thin molded article was performed on the test piece used for measuring the tensile strength of the thin molded article.

The appearance of the injection molded product and the thin molded product was evaluated according to the following criteria. ：: Appearance is beautiful and little change in color tone is observed. ×: A change in color tone or the like is observed on the surface of the molded product.

(II) Raw materials used (1) Modified polyphenylene ether of component (A), polyphenylene ether (i) 50-liter capacity jacket equipped with a stirrer, thermometer, condenser and air inlet tube reaching the bottom of the autoclave Xylene in an autoclave with 17.
After charging 1 kg, 6830 g of methanol, 6110 g of 2,6-dimethylphenol and 120 g of sodium hydroxide to form a uniform solution, the solution was mixed with 169 g of diethanolamine and 138.5 g of di-n-butylamine (2,6
0.0233 mol per 1 mol of dimethylphenol) and 4.95 g of manganese chloride tetrahydrate were added to a solution of 500 g of methanol.

Then, while stirring the contents vigorously, air was blown into the contents at a flow rate of 5 L / min. The reaction temperature and pressure were maintained at 35 ° C. and 9 kg / cm ² respectively. The supply of air was stopped when 7 hours had passed since the start of air blowing, and the reaction mixture was poured into a mixture of 330 g of acetic acid and 24.5 kg of methanol. The resulting slurry was filtered under reduced pressure to isolate wet polyphenylene ether. The isolated polyphenylene ether was washed with 36 kg of methanol, and dried under reduced pressure at 150 ° C. overnight to obtain 5.8 kg of dry polyphenylene ether. The number average molecular weight of this polyphenylene ether is 60
00 and the number average degree of polymerization was 50. Hereinafter, the present polyphenylene ether may be abbreviated as RR-1. Table 1 shows the nitrogen content of various amines of RR-1. Now, it can be seen that the proportion of 0.0047 in the 2- and 6-position of a substituted methyl group of the polyphenylene ether (0.47%) is replaced with tertiary dibutylamino methyl group.

(Ii) Twin screw extruder (manufactured by Ikegai Iron Works, Ltd.)
The hopper of PCM-2) was set to a nitrogen atmosphere, and polyphenylene ether RR-1 was charged and supplied to the hopper together with the stabilizer. On the other hand, kneading was performed at a cylinder temperature of 280 ° C. and a screw rotation speed of 100 rpm while devolatilizing the twin screw extruder. ,
Granulation was performed. Hereinafter, the obtained modified polyphenylene ether may be abbreviated as AA-1. Table 1 shows AA-
1 shows the nitrogen content of various amines. Compared to RR-1, it can be seen that the amount of tertiary amine decreases and the amount of primary amine increases.

[0058] Table 2 shows the results of thermogravimetric analysis of RR-1 and AA-1.
It can be seen that AA-1 is higher under both the air atmosphere and the nitrogen atmosphere in both the main decomposition temperature and the decomposition start temperature, and has excellent thermal stability.

[0059] * Not determined due to weight increase due to oxidation.

(2) Liquid crystal polyester of component (B) (i) p-acetoxybenzoic acid 10.8 kg (60 mol), terephthalic acid 2.49 kg (15 mol), isophthalic acid 0.83 kg (5 mol) 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. Hereinafter, the liquid crystal polyester is abbreviated as BB-1. This polymer showed optical anisotropy at 340 ° C. or more under pressure. The repeating structural units of the liquid crystal polyester BB-1 are as follows.

[0061]

Embedded image

Examples 1 to 3 and Comparative Examples 1 to 3 The components shown in Table 3 were blended together with a stabilizer, kneaded, injection-molded, and measured for various physical properties. Table 3 shows the obtained results. The resin composition of the present invention has excellent heat resistance, weld strength, molded product dimensional stability, etc., has an excellent appearance, can be formed into a thin wall, and is a resin which is inexpensive compared to liquid crystal polyester because it contains polyphenylene ether as a main component. It can be seen that the composition is obtained.

[0063]

[Table 3]

[0064]

The thermoplastic resin composition of the present invention is a resin composition having good moldability and thin-wall moldability and excellent heat resistance and mechanical properties, particularly excellent weld strength and dimensional stability. By utilizing such characteristics, injection molding or extrusion molding is used for various molded products such as large molded products, thin molded products, sheets, tubes, films, fibers, laminates, coating materials and the like.

[Brief description of the drawings]

FIG. 1 is a plan view of a test piece for measuring weld strength.

[Explanation of symbols]

 1. Weld line 2. 2. Cut-out part including weld line (hatched part) Gate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 71/12 C08G 65/48 C08L 67/00-67/04

Claims (3)

(57) [Claims] (A) The following structural unit (1) (Wherein R 1 and R 2 are each independently selected from hydrogen and a hydrocarbon group having 1 to 20 carbon atoms.) In a polyphenylene ether having a number average degree of polymerization of 20 to 1200, the number average degree of polymerization is represented by X And the ratio of 0.02 / X to 1 / X of the total of the methyl groups at the 2- and 6-positions of the phenylene group is the aminomethyl group (—CH ₂
A modified polyphenylene ether substituted with NH ₂ ) , and (B) a liquid crystalline polyester, wherein components (A) and (B)
Of the component (A) exceeds 75% by weight.
0.5% by weight or less and the component (B) is less than 25% by weight.
A thermoplastic resin composition characterized in that the amount is not less than% by weight. (2) The liquid crystalline polyester of component (B) is 400 ° C
Characterized by forming an anisotropic melt at the following temperatures:
The thermoplastic resin composition according to claim 1. (3) The reduced viscosity (ηsp / c) of the component (A) is 0.3
2. The method according to claim 1, wherein the pressure is from 0.65 dl / g.
3. The thermoplastic resin composition according to 2.