JPH11130853A - Liquid crystalline resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid crystalline resin, a liquid crystalline polyester and/or liquid crystalline polyesteramide composed of dioxybiphenyl units and/or oxybenzoyl units, and containing a specific amount of sulfur component, and improved in color tone, corrosion resistance and hydrolysis resistance. SOLUTION: This liquid crystalline resin is a liquid crystalline polyester [e.g. composed of structural units of formula I, formula II, the formula, O-R1-O, and the formula, CO-R2-CO (R1 is CH2 CH2 or the like; R2 is a group of formula III), respectively] and/or liquid crystalline polyesteramide (e.g. made from p- hydroxybenzoic acid or the like), containing <=5 ppm of sulfur component and composed of dioxybiphenyl units and/or oxybenzoyl units.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a modification of a liquid crystalline resin, and more particularly to a liquid crystalline resin having improved color tone, corrosion resistance and hydrolysis resistance, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for higher performance of plastics, and a number of polymers having various new properties have been developed and marketed. Among them, optics characterized by a parallel arrangement of molecular chains. Attention is paid to the fact that anisotropic liquid crystalline polymers have excellent fluidity and mechanical properties,
In particular, it has high rigidity and moderate wear resistance,
Demand for small molded products is increasing in the fields of electronics and office equipment.

Examples of the polymer forming the anisotropic molten phase include a liquid crystalline polymer obtained by copolymerizing p-hydroxybenzoic acid with polyethylene terephthalate (Japanese Patent Laid-Open No.
No. 9-72393), p-hydroxybenzoic acid and 6
-Hydroxy-2-naphthoic acid copolymerized liquid crystal polymer (JP-A-54-77691), p-hydroxybenzoic acid copolymerized with 4,4'-dihydroxybiphenyl, terephthalic acid and isophthalic acid Polymers (JP-B-57-24407) are known.

[0004]

However, when dihydroxybiphenyl, hydroxybenzoic acid or the like is used as a raw material for a liquid crystalline polymer, these raw materials usually contain sulfur, which is an impurity other than metal atoms, so that the It has been found that the polymer may be colored at the time of polymerization and molding of the polymer, may corrode a metal portion in contact with or in proximity to the resin molded product, or may have reduced hydrolysis resistance. Therefore, an object of the present invention is to solve the above-mentioned problems and to obtain a liquid crystalline resin which is excellent in color tone, corrosion resistance and hydrolysis resistance.

[0005]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention.

That is, the present invention relates to (1) a liquid crystalline polyester and / or a liquid crystalline polyester amide containing one or more units selected from dioxybiphenyl units and oxybenzoyl units in a polymer, A liquid crystalline resin having a content of 5 ppm or less, (2) a liquid crystalline polyester and / or a liquid crystalline polyesteramide containing a dioxybiphenyl unit and produced from 4,4′-dibromobiphenyl. The liquid crystalline resin according to the above (1), which is polymerized using a raw material containing dihydroxybiphenyl or a derivative thereof, and (3) the liquid crystalline polyester is represented by the following (I), (II) and
Liquid crystalline polyester having a structural unit of (IV), or
The liquid crystalline resin according to the above (1) or (2), comprising a liquid crystalline polyester having structural units of (I), (II), (III) and (IV).

Embedded image (However, R1 in the formula is

Embedded image R2 represents one or more groups selected from

Embedded image Represents one or more groups selected from In the formula, X represents a hydrogen atom or a chlorine atom. (4) The liquid crystalline polyester comprises the structural units (I), (II), (III) and (IV), and the total of the structural units (I) and (II) is the structural units (I), (II) and (II
35 to 95 mol% of the total of the structural units (I), (65) to 5 mol% of the total of the structural units (I), (II) and (III), and the structural units (I) and (II) The molar ratio [(I) / (II)] is 7
0/30 to 95/5, and the structural unit (IV) is the structural unit (I
The liquid crystalline resin according to the above (3), which is substantially equimolar to the sum of (I) and (III), and (5) 100 parts by weight of the liquid crystal resin according to any one of the above (1) to (4), and 5-300
(6) Dihydroxybiphenyl or a derivative thereof is produced from 4,4′-dibromobiphenyl, and polymerized using a raw material containing the dihydroxybiphenyl or a derivative thereof to obtain the above-mentioned compound. (1) A method for producing a liquid crystalline resin, which comprises producing the liquid crystalline resin according to any one of (1) to (4),
(7) The method for producing a liquid crystalline resin according to the above (6), wherein the sulfur component content in dihydroxybiphenyl or a derivative thereof is 5 ppm or less; (8) The liquid crystalline property according to any of the above (1) to (4) (9) The resin molded article according to (8) above, wherein the resin molded article is a small molded article, and (10) the resin molded article. Is a resin molded product according to the above (8) or (9), which is a metal insert molded product.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The liquid crystalline resin of the present invention is a liquid crystalline resin selected from dioxybiphenyl units and oxybenzoyl units.
A liquid crystalline polyester and / or a liquid crystalline polyesteramide which form an anisotropic molten phase containing at least one kind of units, in addition to these units, an aromatic oxycarbonyl unit,
A liquid crystalline polyester forming an anisotropic molten phase comprising at least one structural unit selected from an aromatic dioxy unit, an aromatic dicarbonyl unit, an ethylenedioxy unit, and the like;
Alternatively, the above structural unit and an aromatic iminocarbonyl unit,
A liquid crystalline polyesteramide that forms an anisotropic molten phase composed of structural units selected from aromatic diimino units and aromatic iminooxy units may be used.

Preferred examples of the liquid crystalline polyester forming an anisotropic molten phase having one or more units selected from the above dioxybiphenyl units and oxybenzoyl units are (I), (II) and ( Liquid crystalline polyester forming an anisotropic molten phase composed of structural units III) and (IV) or liquid crystal forming an anisotropic molten phase composed of structural units of (I), (II) and (IV) Polyester.

[0009]

Embedded image (However, R1 in the formula is

Embedded image R1 represents one or more groups selected from

Embedded image And at least one group selected from In the formula, X represents a hydrogen atom or a chlorine atom. The total of the above structural units (II) and (III) and the structural unit
(IV) is preferably substantially equimolar.

The structural unit (I) is a structural unit formed from p-hydroxybenzoic acid, the structural unit (II) is a structural unit formed from 4,4′-dihydroxybiphenyl, and the structural unit (III) is ethylene. Glycol, 3,
3 ', 5,5'-tetramethyl-4,4'-dihydroxybiphenyl, hydroquinone, t-butylhydroquinone, phenylhydroquinone, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,2
-Bis (4-hydroxyphenyl) propane and 4,
A structural unit formed from one or more dihydroxy compounds selected from 4′-dihydroxydiphenyl ether,
The structural unit (IV) is terephthalic acid, isophthalic acid,
4'-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-bis (phenoxy) ethane-4,
4'-dicarboxylic acid, 1,2-bis (2-chlorophenoxy) ethane-4,4'-dicarboxylic acid and 4,4 '
Each of one or more structural units generated from an aromatic dicarboxylic acid selected from diphenyl ether dicarboxylic acids is shown.

Examples of the liquid crystalline polyesteramide include p-hydroxybenzoic acid, a liquid crystalline polyesteramide formed from 4,4'-dihydroxybiphenyl and terephthalic acid, p-aminobenzoic acid, and polyethylene terephthalate (Japanese Patent Laid-Open JP-A-64-33123).

The liquid crystalline polyester which can be preferably used in the present invention is a copolymer comprising the above structural units (I), (II) and (IV), or (I), (II),
It is a copolymer comprising (III) and (IV), and the copolymerization amount of the above structural units (I), (II), (III) and (IV) is arbitrary. However, the following copolymerization amount is preferred from the viewpoint of fluidity.

That is, when the above structural unit (III) is contained, the total of the above structural units (I) and (II) is the sum of the structural units (I) and (I) from the viewpoint of heat resistance, flame retardancy and mechanical properties.
It is preferably from 35 to 95 mol%, more preferably from 40 to 93 mol%, based on the total of I) and (III). Further, the structural unit (III) is preferably 65 to 3 mol%, more preferably 60 to 7 mol%, based on the total of the structural units (I), (II) and (III).
Is more preferred. The molar ratio [(I) / (II)] between the structural units (I) and (II) is preferably 70/30 to 95/5, more preferably 75/30, from the viewpoint of the balance between heat resistance and fluidity. / 25 to 93/7. The structural unit (IV) is substantially equimolar to the sum of the structural units (II) and (III).

On the other hand, when the structural unit (III) is not contained, the structural unit (I) is replaced with the structural unit (I) from the viewpoint of fluidity.
It is preferably from 40 to 90 mol%, more preferably from 60 to 88 mol%, based on the total of (II) and (II), and the structural unit (IV) is substantially equimolar to the structural unit (II). is there.

In the polycondensation of the liquid crystalline polyester which can be preferably used in the present invention, in addition to the components constituting the above structural units (I) to (IV), 3,3'-diphenyldicarboxylic acid, 2,2 Aromatic dicarboxylic acids such as' -diphenyldicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid and dodecandioic acid; alicyclic dicarboxylic acids such as hexahydroterephthalic acid; chlorohydroquinone, methylhydroquinone, 4,4'-dihydroxydiphenyl sulfone, 4,
4'-dihydroxydiphenyl sulfide, 4,4'-
Aromatic diols such as dihydroxybenzophenone,
Aliphatics such as 4-butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol;
Alicyclic diols and m-hydroxybenzoic acid, 2,6
Aromatic hydroxycarboxylic acids such as -hydroxynaphthoic acid and p-aminophenol, p-aminobenzoic acid and the like can be further copolymerized within a range that does not impair the liquid crystallinity.

The method for polymerizing the liquid crystalline resin in the present invention is not particularly limited, and it can be produced according to a known method.

For example, in the production of the liquid crystalline polyester, it can be produced according to a known polycondensation method, and the following production method is preferable.

(1) p-acetoxybenzoic acid and 4,
Diacylated aromatic dihydroxy compounds such as 4'-diacetoxybiphenyl, diacetoxybenzene, and 2,
A method of producing from 6-naphthalenedicarboxylic acid, terephthalic acid, isophthalic acid and other aromatic dicarboxylic acids by deacetic acid condensation polymerization.

(2) p-hydroxybenzoic acid and 4,
4′-dihydroxybiphenyl, an aromatic dihydroxy compound such as hydroquinone and an aromatic dicarboxylic acid such as 2,6-naphthalenedicarboxylic acid, terephthalic acid, and isophthalic acid are reacted with acetic anhydride to acylate a phenolic hydroxyl group. A method of producing by a deacetic acid polycondensation reaction.

(3) Phenyl esters of p-hydroxybenzoic acid and aromatic dihydroxy compounds such as 4,4'-dihydroxybiphenyl, hydroquinone and 2,6
-A method of producing from a diphenyl ester of an aromatic dicarboxylic acid such as naphthalenedicarboxylic acid, terephthalic acid, isophthalic acid, etc. by a phenol removal polycondensation reaction.

(4) p-hydroxybenzoic acid and 2,
A predetermined amount of diphenyl carbonate is reacted with an aromatic dicarboxylic acid such as 6-naphthalenedicarboxylic acid, terephthalic acid, or isophthalic acid to form diphenyl esters, and aromatic dihydroxy compounds such as 4,4′-dihydroxybiphenyl and hydroquinone And a production method by a dephenol polycondensation reaction.

(5) Polyester polymers such as polyethylene terephthalate, oligomers or bis (β-
(Hydroxyethyl) terephthalate or the like, in the presence of bis (β-hydroxyethyl) ester of an aromatic dicarboxylic acid, by the method of (1) or (2).

Although these polycondensation reactions proceed without a catalyst, metal compounds such as stannous acetate, tetrabutyl titanate, potassium acetate and sodium acetate, antimony trioxide and metallic magnesium can also be used.

The liquid crystal resin of the present invention has a sulfur content of 5
ppm or less, preferably 4 ppm or less, more preferably 3 ppm
It is as follows.

If the content of the sulfur component in the liquid crystalline resin is too large, the color tone of the obtained polyester becomes poor, and the corrosion resistance of the obtained liquid crystalline resin or the liquid crystalline resin composition,
It is difficult to sufficiently increase the hydrolysis resistance.

It should be noted that, in the present invention, the method for measuring the sulfur component content is to use X-ray fluorescence analysis.

It is considered that the content of the sulfur component in the liquid crystal resin is particularly affected by the content of the sulfur component contained in dihydroxybiphenyl, which is a raw material for forming dioxybiphenyl units and oxybenzoyl units, and hydroxybenzoic acid. Particularly, when a large amount of sulfur component is mixed in producing dihydroxybiphenyl or its derivative as a raw material of dioxybiphenyl unit such as 4,4'-dioxybiphenyl unit, or the total content of p-oxybenzoyl unit Is relatively large.

Further, when a terminal blocking agent is used, a sulfur component may be mixed in from 4-phenylphenol, phenol or the like used as a terminal blocking agent.

Usually, in the case of a polymer having a dioxybiphenyl unit such as a 4,4'-dioxybiphenyl unit, a sulfur component is produced as an impurity or a residue of a sulfuric acid treatment step when producing the corresponding monomer, dihydroxybiphenyl or a derivative thereof. And mixed into the polymer after polymerization.

The method for producing dihydroxybiphenyl such as 4,4'-dihydroxybiphenyl includes
Method for producing from 4'-dibromobiphenyl (Method A)
Or alkali melting method (method B) produced from sulfonated biphenyl, 3,3 ′, 5,5′-tetrabutyl-
Method for producing from 4,4'-dihydroxybiphenyl (Method C), Method for producing from 4,4'-diisopropylbiphenyl (Method D) Enzymatic method for producing from biphenyl having a substituent such as tert-butyl (Method E) )It has been known.

In order to make the content of the sulfur component in the liquid crystalline resin 5 ppm or less, the content of the sulfur component in dioxybiphenyl is preferably set to 10 ppm or less, particularly preferably 7 ppm or less. More preferably, it is 5 ppm or less.

However, among the above production methods, 4,4'-dihydroxybiphenyl obtained by the method B uses a sulfonated biphenyl, so that the content of the sulfur component in the hydroxybiphenyl is not less than 20 ppm and not more than 10 ppm. Extremely difficult. In addition, C method, D method, E method
In the method, a large amount of sulfonic acid such as sulfuric acid, paratoluenesulfonic acid, benzenesulfonic acid, etc. is used in the dealkylation step, so that the incorporation of sulfur components is inevitable, and the content of sulfur components in hydroxybiphenyl is reduced to 10 pp.
It is extremely difficult to make it less than m.

In the method for producing from 4,4'-dibromobiphenyl in the method A, sulfuric acid is used in the debromination step, but the amount of the sulfur component is small, and the sulfur component content is reduced to 10 ppm or less by further purification. It is possible to

In the case of a polymer having an oxybenzoyl unit, a sulfur component is mixed in the polymer after polymerization.

That is, the method of producing p-hydroxybenzoic acid from a potassium salt of phenol and carbon dioxide gas is generally used for hydroxybenzoic acid such as p-hydroxybenzoic acid which is a raw material for the p-oxybenzoyl unit.

In the above method, sulfuric acid is used when hydrolyzing monopotassium p-hydroxybenzoate, so that usually the obtained p-hydroxybenzoic acid is 2 to 20%.
Contains ppm sulfur component.

Some of the liquid crystalline resins of the present invention can measure the logarithmic viscosity in pentafluorophenol, in which case the value measured at 60 ° C. at a concentration of 0.1 g / dl is 0.1 g / dl. 03 or more, preferably 0.05 to 10.0 d
l / g is particularly preferred.

The melt viscosity of the liquid crystalline polyester of the present invention is preferably from 5 to 20,000 poise, more preferably from 10 to 10,000 poise.

The melt viscosity is calculated as melting point (Tm) +10
It is a value measured by a Koka type flow tester under the condition of ° C and a shear rate of 1,000 (1 / second).

Here, the melting point (Tm) refers to an endothermic peak temperature (Tm) observed when a polymer that has been polymerized is measured from room temperature under a heating condition of 20 ° C./min.
After observation at m1), the temperature is maintained at a temperature of Tm1 + 20 ° C. for 5 minutes, cooled once to room temperature at a temperature lowering condition of 20 ° C./min, and then measured again at a temperature rising condition of 20 ° C./min. Refers to the endothermic peak temperature (Tm2).

The liquid crystalline resin of the present invention may contain a filler. The filler that can be used is not particularly limited, but may be fibrous and / or non-fibrous (for example, plate-like, Powdered, granular, etc.) fillers can be used. Specifically, for example, glass fiber, PAN-based or pitch-based carbon fiber, stainless fiber, metal fiber such as aluminum fiber or brass fiber, organic fiber such as aromatic polyamide fiber, gypsum fiber, ceramic fiber, asbestos fiber, zirconia Fibrous such as fiber, alumina fiber, silica fiber, titanium oxide fiber, silicon carbide fiber, rock wool, potassium titanate whisker, barium titanate whisker, aluminum borate whisker, silicon nitride whisker, whisker-like filler, mica, talc, Powder, granular or plate-like fillers such as kaolin, silica, calcium carbonate, glass beads, glass flakes, glass microballoons, clay, molybdenum disulfide, wollastenite, titanium oxide, zinc oxide, calcium polyphosphate, graphite, etc. Is . Among the above fillers, glass fibers are preferably used. The type of the glass fiber is not particularly limited as long as it is generally used for reinforcing a resin. For example, a long fiber type or a short fiber type chopped strand, a milled fiber or the like can be used. Further, two or more of the above fillers can be used in combination. The surface of the filler used in the present invention is a known coupling agent (for example, a silane coupling agent, a titanate coupling agent, etc.),
It can be used after being treated with another surface treating agent.

The glass fiber may be coated or bundled with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin.

The amount of the filler is 100
Not more than 300 parts by weight, preferably 10 parts by weight.
To 250 parts by weight, more preferably 20 to 150 parts by weight.

The liquid crystalline resin of the present invention contains an antioxidant and a heat stabilizer (for example, hindered phenol, hydroquinone, phosphites and the like) and a coloring inhibitor (phosphite, hypophosphite). ), UV absorbers (eg, resorcinol, salicylate, benzotriazole, benzophenone, etc.), lubricants and release agents (eg, montanic acid and its salts, its esters, its half esters, stearyl alcohol, stearamide, and polyethylene wax), dyes ( A conventional additive such as a coloring agent including a nigrosine or the like and a pigment (eg, cadmium sulfide or phthalocyanine), a crystal nucleating agent, a plasticizer, a flame retardant, a flame retardant auxiliary, an antistatic agent, etc. Properties can be further imparted.

The method of adding these is preferably melt kneading, and a known method can be used for melt kneading. For example, Banbury mixer, rubber roll machine,
Using a kneader, single screw or twin screw extruder, etc.
The composition can be melt-kneaded at a temperature of from about 370 ° C. to a composition.

The thus obtained liquid crystalline resin or its composition can be subjected to ordinary molding such as injection molding, extrusion molding, compression molding, etc., and is extremely useful as various molded products for electric / electronic parts, precision parts, automobile parts and the like. It is. In addition, because of excellent color tone, by adding a colorant,
Excellent colored molded articles can be obtained.

The liquid crystalline resin of the present invention and its composition are excellent in corrosion resistance, excellent hydrolysis resistance and color tone, and are therefore processed into various molded articles such as three-dimensional molded articles, sheets and container pipes. For example, various gears, various cases, sensors, LEP lamps, connectors, sockets, resistors, relay cases, switches, coil bobbins, capacitors, variable condenser cases, optical pickups,
Oscillator, various terminal boards, transformers, plugs, printed wiring boards, tuners, speakers, microphones, headphones, small motors, magnetic head bases, power modules, housings, semiconductors, liquid crystals, FDD carriages, FDD chassis, motor brush holders, Electrical and electronic parts such as parabolic antennas and computer-related parts; VTR parts, TV parts, irons, hair dryers, rice cooker parts, microwave parts,
Audio parts, audio equipment parts such as audio laser discs and compact discs, lighting parts, refrigerator parts,
Home and office electrical product parts, office computer related parts, telephone related parts, facsimile related parts, copier related parts, cleaning jigs, oilless bearings, stern bearings, represented by air conditioner parts, typewriter parts, word processor parts, etc. Various bearings such as underwater bearings, motor parts, mechanical parts such as lighters and typewriters, optical equipment such as microscopes, binoculars, cameras and watches, precision equipment parts; alternator terminals, alternator connectors, IC regulator, potentiometer base for light deer, various valves such as exhaust gas valve, various pipes related to fuel, exhaust system, intake system, air intake nozzle snorkel,
Intake manifold, fuel pump, engine cooling water joint, carburetor main body, carburetor spacer, exhaust gas sensor, cooling water sensor, oil temperature sensor, brake pad wear sensor, throttle position sensor, crankshaft position sensor, air flow meter, brake butt Wear sensor, thermostat base for air conditioner, heating and hot air flow control valve, brush holder for radiator motor, water pump impeller, turbine vane, wiper motor related parts, dust switcher, starter switch, starter relay, wire harness for transmission, window Osher nozzle, air conditioner panel switch board, fuel related electromagnetic valve coil, For automotive and vehicle-related parts such as fuse connectors, horn terminals, electrical component insulation boards, step motor rotors, lamp sockets, lamp reflectors, lamp housings, brake pistons, solenoid bobbins, engine oil filters, ignition device cases, and other various applications Useful.

Above all, it can be used extremely practically as a small molded product used for a small molded component, for example, a small component of 5 cc or less, by utilizing its excellent color tone and hydrolysis resistance. In particular, it is very practical for molded products that are small built-in parts such as connectors such as SIMM sockets, CD pickup lens holders and various small gears.

In addition, when excellent corrosion resistance and hydrolysis resistance are utilized, it can be very practically used as a metal insert type molded product.

[0050]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the invention.

Each evaluation was measured according to the method described below.

(1) Whiteness (W value), Yellowness (YI value) A 127 mm × 12.7 mm × 3.12 mm bending test piece was subjected to Sumitomo Heavy Industries Promat 25/40 at a cylinder temperature of 32.
The test piece was molded at 5 ° C. and a mold temperature of 90 ° C., and the whiteness (W value) and yellowness (YI value) of the test piece were measured using an SM color computer apparatus manufactured by Suga Test Instruments Co., Ltd.

(2) Corrosion test In a 20 cc ampoule tube, 5 g of polymer and 5 ×
A copper plate of 15 × 0.5 mm is charged, sealed and sealed at 150 ° C./1
Treat in an oven for 000 hours and remove the copper plate after the treatment. Next, the surface resistance was measured using a MICRO OHM METER manufactured by Yamazaki Seiki Co., Ltd. using a four-point contact method with a contact load of 20 gf and a range of 1 mA.
・ The test was performed at 200 mmΩ to 20Ω.

(3) Hydrolysis test An ASTM No. 1 tensile test piece was molded with a Toshiba IS-55EPN at a cylinder temperature of 325 ° C. and a mold temperature of 90 ° C. The obtained test piece was charged into an autoclave together with water and charged at 120 ° C.
, And the tensile strength was measured based on ASTM D638, and the tensile strength when treated at 120 ° C. for 3 days / initial tensile strength × 100 was defined as the tensile strength retention.

(4) Content of sulfur component RIX-1000 manufactured by Rigaku Denki was used. The sulfur content was measured from a calibration curve at a tube voltage of 50 kV and a tube current of 50 mA using a chromium tube. As a raw material for polymerization, the powder is 30
A predetermined amount was filled in an mmφ powder measurement folder, and the measurement was performed. The polymer obtained by polymerization was injection-molded into a 30 mmφ × 2 mm thick disc-shaped product,
The measurement was performed using a folder of mφ.

Example 1 p-hydroxybenzoic acid (sulfur component content: 2 ppm) 99
5 parts by weight of 4,4'-dihydroxybiphenyl (4,4
4'-dibromobiphenyl, 126 parts by weight of sulfur component content, 112 parts by weight of terephthalic acid (sulfur component content less than 0.3 ppm), having an intrinsic viscosity of about 0.6 dl / g. 216 parts by weight of polyethylene terephthalate (sulfur component content less than 0.3 ppm) and acetic anhydride (sulfur component content less than 0.3 ppm) 96
0 parts by weight were charged into a reaction vessel equipped with a stirring blade and a distillation tube,
Polymerization was performed. Sulfur content 2 ppm, liquid crystal onset temperature 2
A resin (A-1) pellet having a logarithmic viscosity of 1.49 dl / g at 94 ° C. and a weight average molecular weight of about 22,000 was obtained. Then, a test piece was obtained from the pellet by a method for each evaluation item and evaluated. Table 1 shows the evaluation results.

Example 2 p-hydroxybenzoic acid (sulfur component content: 2 ppm) 99
4 parts by weight of 4,4'-dihydroxybiphenyl (4,4
4'-dibromobiphenyl, sulfur component content 3 ppm) 373 parts by weight, 2,
6-hydroxynaphthoic acid (sulfur component content 0.3 ppm
), 84 parts by weight of terephthalic acid (sulfur component content: 0.1).
329 parts by weight (less than 3 ppm) and 1308 parts by weight of acetic anhydride (sulfur component content less than 0.3 ppm) were charged into a reaction vessel equipped with a stirring blade and a distilling tube, and polymerized. Sulfur content 2 ppm, liquid crystal onset temperature 309 ° C, logarithmic viscosity 6.28
dl / g, a resin having a weight average molecular weight of about 32,000 (A
-2) A pellet was obtained. Then, a test piece was obtained from the pellet by a method for each evaluation item and evaluated. Table 1 shows the evaluation results.
Shown in

Example 3 p-Hydroxybenzoic acid (sulfur content: 2 ppm) 93
2 parts by weight of 4,4'-dihydroxybiphenyl (4,4
419 parts by weight of terephthalic acid (sulfur content less than 0.3 ppm), isophthalic acid (sulfur content 0.3 ppm) Less) 9
3 parts by weight and 1263 parts by weight of acetic anhydride (sulfur component content of less than 0.3 ppm) were charged into a reaction vessel equipped with a stirring blade and a distilling tube to perform polymerization. Resin (A-3) pellets having a sulfur component content of 3 ppm, a liquid crystal onset temperature of 306 ° C., an logarithmic viscosity of 6.12 dl / g, and a weight average molecular weight of about 31,000 were obtained. Then, a test piece was obtained from the pellet by a method for each evaluation item and evaluated. Table 1 shows the evaluation results.

Comparative Example 1 Polymerization was carried out in the same composition as in Example 1 except that the sulfur component content of 4,4'-dihydroxybiphenyl was 150 ppm (produced by a method of producing from sulfonated biphenyl). Was done. Sulfur component content 17pp
m, liquid crystal onset temperature 294 ° C., logarithmic viscosity 1.55 dl /
g, resin having a weight average molecular weight of about 23,000 (A-4)
Pellets were obtained. Then, a test piece was obtained from the pellet by a method for each evaluation item and evaluated. Table 1 shows the evaluation results.

Comparative Example 2 Polymerization was carried out in the same composition as in Example 3 except that the sulfur component content of 4,4'-dihydroxybiphenyl was 150 ppm (produced by a method of producing from sulfonated biphenyl). Was done. Sulfur component content 43pp
m, liquid crystal onset temperature 309 ° C., logarithmic viscosity 6.28 dl /
g, resin having a weight average molecular weight of about 32,000 (A-5)
Pellets were obtained. Then, a test piece was obtained from the pellet by a method for each evaluation item and evaluated. Table 1 shows the evaluation results.

Example 4, Comparative Example 3 After the fillers were dry-blended at the ratios shown in Table 1 in the LCPs produced in Example 1 and Comparative Example 1, the pellets were obtained by melt-kneading with a 30 mmφ twin screw extruder. . Then, a test piece was obtained from the pellet by a method for each evaluation item.

Table 1 shows the evaluation results.

[0063]

[Table 1]

From the results shown in Table 1, the liquid crystalline resin composition of the present invention can provide a material having improved color tone and improved corrosion resistance and hydrolysis resistance.

Further, when a metal insert-type molded product was molded, a molded product excellent in corrosion resistance could be molded.

[0066]

Industrial Applicability The liquid crystalline resin composition and molded article of the present invention have improved color tone and excellent corrosion resistance and hydrolysis resistance, so that they are used in electrical and electronic equipment, precision equipment, and office equipment. It may be suitable for various other uses such as automobile and vehicle related parts.

Claims (10)

[Claims] 1. A liquid crystalline polyester and / or a liquid crystalline polyesteramide containing at least one unit selected from dioxybiphenyl units and oxybenzoyl units in a polymer, wherein the sulfur component content is 5 ppm or less. Liquid crystalline resin characterized by the following. 2. A liquid crystalline polyester and / or a liquid crystalline polyester amide containing a dioxybiphenyl unit and polymerized using a raw material containing dihydroxybiphenyl prepared from 4,4'-dibromobiphenyl or a derivative thereof. 2. The liquid crystalline resin according to claim 1, which is a resin. 3. A liquid crystalline polyester having the following structural units (I), (II) and (IV), or
3. The liquid crystalline resin according to claim 1, comprising a liquid crystalline polyester having structural units of (I), (II), (III) and (IV). Embedded image (Where R1 in the formula is And R2 represents one or more groups selected from Represents one or more groups selected from In the formula, X represents a hydrogen atom or a chlorine atom. ) 4. A liquid crystalline polyester comprising the structural units (I) and (I)
(I), (III) and (IV), wherein the total of the structural units (I) and (II) is 35 to 95 of the total of the structural units (I), (II) and (III).
Mol%, the structural unit (III) is composed of the structural units (I), (II) and (II)
65 to 5 mol% of the total of the structural units (I) and (I)
The molar ratio [(I) / (II)] of I) is 70/30 to 95/5, and the structural unit (IV) is substantially equimolar to the sum of the structural units (II) and (III). The liquid crystalline resin according to claim 3. 5. The liquid crystal resin 1 according to claim 1,
A liquid crystalline resin composition obtained by adding 5 to 300 parts by weight of an inorganic filler to 00 parts by weight. 6. The liquid crystalline compound according to claim 1, wherein the dihydroxybiphenyl or a derivative thereof is produced from 4,4′-dibromobiphenyl, and is polymerized using a raw material containing the dihydroxybiphenyl or a derivative thereof. A method for producing a liquid crystalline resin, which comprises producing a resin. 7. The method for producing a liquid crystalline resin according to claim 6, wherein the sulfur component content in dihydroxybiphenyl or a derivative thereof is 5 ppm or less. 8. A resin molded article obtained by molding the liquid crystalline resin according to claim 1 or the liquid crystalline resin composition according to claim 5. 9. The resin molded product according to claim 8, wherein the resin molded product is a small molded product. 10. The resin molded product according to claim 8, wherein the resin molded product is a metal insert type molded product.