JP2012206296A - Method for manufacturing liquid crystal polyester composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably manufacture a liquid crystal polyester composition, which includes liquid crystal polyester, a fibrous filler, a lamellar filler and a granular filler, with good productivity.SOLUTION: An extruder, which has a cylinder, the screw arranged in the cylinder and the first, second and third supply parts successively provided in the cylinder from the upstream side, is used to successively supply the liquid crystal polyester, the fibrous filler and the lamellar filler, and the granular filler into the cylinder from the first, second and third supply parts while rotating the screw. The liquid crystal polyester, the fibrous filler, the lamellar filler and the granular filter are melted and kneaded to be extruded.

Description

  The present invention relates to a method for producing a liquid crystal polyester composition comprising a liquid crystal polyester, a fibrous filler, a plate-like filler, and a granular filler.

  Liquid crystalline polyester is excellent in melt fluidity and heat resistance, and is therefore suitably used as an injection molding material for manufacturing electrical and electronic parts. Since the directivity tends to occur, the molded body is easily warped, and the weld strength of the molded body tends to be low, so that the molded body is likely to crack (weld crack). In order to solve such a problem, various studies have been made on blending a fibrous filler and a plate-like filler with liquid crystal polyester (see, for example, Patent Documents 1 to 3).

JP 2002-294038 A International Publication No. 2008/023839 JP 2010-003661 A

  As disclosed in Patent Documents 1 to 3, a conventional liquid crystal polyester composition obtained by blending a fibrous filler and a plate-like filler into a liquid crystal polyester does not necessarily have a sufficient weld strength of the molded product. If the content of the fibrous filler is increased in order to improve it, the melt fluidity is lowered and poor filling tends to occur. As a result of studies to solve this problem, the present inventor is excellent in melt fluidity by adding a granular filler to the liquid crystalline polyester in addition to the fibrous filler and the plate-like filler. It has been found that a liquid crystal polyester composition is obtained that gives a molded product that is less likely to warp or crack. Further, as a result of further investigation to mass-produce the liquid crystal polyester composition containing the liquid crystal polyester, the fibrous filler, the plate-like filler, and the granular filler, a cylinder, a screw disposed in the cylinder, Using an extruder having a plurality of supply parts provided in the cylinder, while rotating the screw, the liquid crystal polyester and each filler are supplied from the predetermined supply part into the cylinder, melt-kneaded and extruded. Thus, it has been found that discharge unevenness and strand breakage can be prevented, and that the liquid crystal polyester composition can be stably produced with good productivity, and the present invention has been completed.

  That is, this invention uses the extruder which has a cylinder, the screw arrange | positioned in the said cylinder, and the 1st supply part, the 2nd supply part, and the 3rd supply part which were sequentially provided in the said cylinder from the upstream. While rotating the screw, liquid crystal polyester is supplied into the cylinder from the first supply part, fibrous filler and plate-like filler are supplied from the second supply part, and granular filler is supplied to the first supply part. 3. A method for producing a liquid crystal polyester composition that is supplied from a three supply unit and melt-kneaded and extruded the liquid crystal polyester, the fibrous filler, the plate-like filler, and the granular filler.

  ADVANTAGE OF THE INVENTION According to this invention, the liquid crystal polyester composition containing liquid crystalline polyester, a fibrous filler, a plate-shaped filler, and a granular filler can be manufactured stably with good productivity.

It is sectional drawing which shows typically the example of the extruder used by this invention.

  The liquid crystalline polyester is a liquid crystalline polyester that exhibits liquid crystallinity in a molten state, and is preferably melted at a temperature of 450 ° C. or lower. The liquid crystal polyester may be a liquid crystal polyester amide, a liquid crystal polyester ether, a liquid crystal polyester carbonate, or a liquid crystal polyester imide. The liquid crystal polyester is preferably a wholly aromatic liquid crystal polyester using only an aromatic compound as a raw material monomer.

  A typical example of the liquid crystal polyester is polymerization (polycondensation) of an aromatic hydroxycarboxylic acid, an aromatic dicarboxylic acid, and at least one compound selected from the group consisting of an aromatic diol, an aromatic hydroxyamine, and an aromatic diamine. At least one compound selected from the group consisting of aromatic dicarboxylic acids and aromatic diols, aromatic hydroxyamines and aromatic diamines, And those obtained by polymerizing a polyester such as polyethylene terephthalate and an aromatic hydroxycarboxylic acid. Here, the aromatic hydroxycarboxylic acid, the aromatic dicarboxylic acid, the aromatic diol, the aromatic hydroxyamine, and the aromatic diamine are each independently replaced with a part or all of the polymerizable derivative. Also good.

  Examples of polymerizable derivatives of a compound having a carboxyl group such as aromatic hydroxycarboxylic acid and aromatic dicarboxylic acid include those obtained by converting a carboxyl group into an alkoxycarbonyl group or an aryloxycarbonyl group (ester), carboxyl Examples include those obtained by converting a group into a haloformyl group (acid halide), and those obtained by converting a carboxyl group into an acyloxycarbonyl group (acid anhydride). Examples of polymerizable derivatives of hydroxyl group-containing compounds such as aromatic hydroxycarboxylic acids, aromatic diols and aromatic hydroxyamines include those obtained by acylating hydroxyl groups and converting them to acyloxyl groups (acylated products) ). Examples of polymerizable derivatives of amino group-containing compounds such as aromatic hydroxyamines and aromatic diamines include those obtained by acylating an amino group and converting it to an acylamino group (acylated product).

  The liquid crystalline polyester preferably has a repeating unit represented by the following formula (1) (hereinafter sometimes referred to as “repeating unit (1)”), and the repeating unit (1) and the following formula (2) A repeating unit represented (hereinafter sometimes referred to as “repeating unit (2)”) and a repeating unit represented by the following formula (3) (hereinafter sometimes referred to as “repeating unit (3)”). It is more preferable to have.

(1) —O—Ar ¹ —CO—
(2) —CO—Ar ² —CO—
⁽³⁾ -X-Ar 3 -Y-

(Ar ¹ represents a phenylene group, a naphthylene group, or a biphenylylene group. Ar ² and Ar ³ each independently represent a phenylene group, a naphthylene group, a biphenylylene group, or a group represented by the following formula (4). X And Y each independently represents an oxygen atom or an imino group (—NH—), and each hydrogen atom in the group represented by Ar ¹ , Ar ² or Ar ³ independently represents a halogen atom or an alkyl group. Alternatively, it may be substituted with an aryl group.)

(4) -Ar ⁴ -Z-Ar ^5-

(Ar ⁴ and Ar ⁵ each independently represent a phenylene group or a naphthylene group. Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylidene group.)

As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned. Examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n-hexyl group, 2-ethylhexyl group, An n-octyl group and n-decyl group are mentioned, The carbon number is 1-10 normally. Examples of the aryl group include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, a 1-naphthyl group, and a 2-naphthyl group, and the number of carbon atoms is usually 6 to 20. . When the hydrogen atom is substituted with these groups, the number is usually 2 or less for each group represented by Ar ¹ , Ar ² or Ar ³ , and preferably 1 It is as follows.

  Examples of the alkylidene group include a methylene group, an ethylidene group, an isopropylidene group, an n-butylidene group, and a 2-ethylhexylidene group, and the number of carbon atoms is usually 1 to 10.

The repeating unit (1) is a repeating unit derived from a predetermined aromatic hydroxycarboxylic acid. As the repeating unit (1), Ar ¹ is a p-phenylene group (a repeating unit derived from p-hydroxybenzoic acid), and Ar ¹ is a 2,6-naphthylene group (6-hydroxy-2). -Repeating units derived from naphthoic acid) are preferred.

The repeating unit (2) is a repeating unit derived from a predetermined aromatic dicarboxylic acid. As the repeating unit (2), Ar ² is a p-phenylene group (repeating unit derived from terephthalic acid), Ar ² is an m-phenylene group (repeating unit derived from isophthalic acid), and Ar Those in which ² is a 2,6-naphthylene group (a repeating unit derived from 2,6-naphthalenedicarboxylic acid) are preferred.

The repeating unit (3) is a repeating unit derived from a predetermined aromatic diol, aromatic hydroxylamine or aromatic diamine. As the repeating unit (3), Ar ³ is a p-phenylene group (repeating unit derived from hydroquinone, p-aminophenol or p-phenylenediamine), and Ar ³ is a 4,4′-biphenylylene group. Those (4,4′-dihydroxybiphenyl, 4-amino-4′-hydroxybiphenyl or repeating units derived from 4,4′-diaminobiphenyl) are preferred.

  The content of the repeating unit (1) is the total amount of all repeating units (the mass equivalent amount of each repeating unit (moles by dividing the mass of each repeating unit constituting the liquid crystal polyester by the formula amount of each repeating unit). ) And the total value thereof) is usually 30 mol% or more, preferably 30 to 80 mol%, more preferably 40 to 70 mol%, still more preferably 45 to 65 mol%. The content of the repeating unit (2) is usually 35 mol% or less, preferably 10 to 35 mol%, more preferably 15 to 30 mol%, still more preferably 17.5 to 27, based on the total amount of all repeating units. .5 mol%. The content of the repeating unit (3) is usually 35 mol% or less, preferably 10 to 35 mol%, more preferably 15 to 30 mol%, still more preferably 17.5 to 27, based on the total amount of all repeating units. .5 mol%. The higher the content of the repeating unit (1), the easier it is to improve the melt fluidity, heat resistance, strength and rigidity. However, if it is too much, the melting temperature and melt viscosity are likely to increase, and the temperature required for molding increases. easy.

  The ratio between the content of the repeating unit (2) and the content of the repeating unit (3) is expressed as [content of repeating unit (2)] / [content of repeating unit (3)] (mol / mol). The ratio is usually 0.9 / 1 to 1 / 0.9, preferably 0.95 / 1 to 1 / 0.95, and more preferably 0.98 / 1 to 1 / 0.98.

  In addition, liquid crystalline polyester may have 2 or more types of repeating units (1)-(3) each independently. The liquid crystalline polyester may have a repeating unit other than the repeating units (1) to (3), and the content thereof is usually 10 mol% or less, preferably 5 with respect to the total amount of all repeating units. It is less than mol%.

  Since the liquid crystal polyester has a repeating unit (3) in which X and Y are each an oxygen atom, that is, having a repeating unit derived from a predetermined aromatic diol, the melt viscosity tends to be low. It is more preferable that the repeating unit (3) has only those in which X and Y are each an oxygen atom.

  The liquid crystalline polyester can be produced by melt polymerizing raw material monomers corresponding to the repeating units constituting the liquid crystalline polyester and solid-phase polymerizing the obtained polymer (hereinafter sometimes referred to as “prepolymer”). preferable. Thereby, high molecular weight liquid crystal polyester having high heat resistance, strength and rigidity can be produced with good operability. Melt polymerization may be carried out in the presence of a catalyst. Examples of this catalyst include metal compounds such as magnesium acetate, stannous acetate, tetrabutyl titanate, lead acetate, sodium acetate, potassium acetate, and antimony trioxide, And nitrogen-containing heterocyclic compounds such as 4- (dimethylamino) pyridine and 1-methylimidazole, and nitrogen-containing heterocyclic compounds are preferably used.

  The liquid polyester has a flow starting temperature of usually 270 ° C. or higher, preferably 270 to 400 ° C., more preferably 280 to 380 ° C. As the flow start temperature is higher, the heat resistance, strength and rigidity are more likely to be improved. However, if the flow start temperature is too high, the melting temperature and the melt viscosity are likely to be high, and the temperature required for the molding is likely to be high.

The flow start temperature is also called flow temperature or flow temperature, and the temperature is raised at a rate of 4 ° C./min under a load of 9.8 MPa (100 kg / cm ² ) using a capillary rheometer while the liquid crystalline polyester is used. Is a temperature showing a viscosity of 4800 Pa · s (48000 poise) when extruded from a nozzle having an inner diameter of 1 mm and a length of 10 mm, and is a measure of the molecular weight of the liquid crystalline polyester (Naide Koide, “ “Liquid Crystal Polymer—Synthesis / Molding / Application—”, CMC Co., Ltd., June 5, 1987, p. 95).

  In the present invention, a liquid crystal polyester composition is produced by blending a fibrous filler, a plate-like filler, and a granular filler with liquid crystal polyester. This liquid crystal polyester composition is excellent in melt fluidity, and gives a molded body in which warpage and cracks hardly occur.

  The fibrous filler may be an inorganic filler or an organic filler. Examples of fibrous inorganic fillers include glass fibers; carbon fibers such as pan-based carbon fibers and pitch-based carbon fibers; ceramic fibers such as silica fibers, alumina fibers and silica-alumina fibers; and metal fibers such as stainless steel fibers. It is done. In addition, whiskers such as potassium titanate whisker, barium titanate whisker, wollastonite whisker, aluminum borate whisker, silicon nitride whisker, and silicon carbide whisker are also included. Examples of fibrous organic fillers include polyester fibers and aramid fibers. Among these, glass fiber is preferably used. Two or more kinds of fibrous fillers may be used as necessary.

  The number average fiber diameter of the fibrous filler is preferably 5 to 20 μm, more preferably 5 to 15 μm, and the number average aspect ratio (number average fiber length / number average fiber diameter) of the fibrous filler is preferably It is 20-500, More preferably, it is 100-500. If the number average aspect ratio of the fibrous filler is too small, the weld strength of the molded body becomes insufficient, and if it is too large, the melt flowability of the liquid crystal polyester composition becomes insufficient. The number average fiber diameter and the number average fiber length of the fibrous filler can be measured by observing with an electron microscope. The number average aspect ratio is that of the raw material fibrous filler blended with the liquid crystal polyester, and the fibrous filler in the liquid crystal polyester composition after blended with the liquid crystal polyester is melt-kneaded. The number average aspect ratio is preferably 10 to 50, more preferably 20 to 40, due to breakage.

  The blending amount of the fibrous filler is preferably 5 to 80 parts by mass, more preferably 10 to 50 parts by mass with respect to 100 parts by mass of the liquid crystalline polyester. If the blending amount of the fibrous filler is too small, the weld strength of the molded body becomes insufficient, and if it is too large, the melt flowability of the liquid crystal polyester composition becomes insufficient.

  As the plate-like filler, an inorganic filler is usually used. Examples of the plate-like inorganic filler include talc, mica, graphite, wollastonite, glass flake, barium sulfate and calcium carbonate. Of these, talc and mica are preferable, and talc is more preferable. Two or more types of plate-like fillers may be used as necessary.

  The volume average particle diameter of the plate-like filler is preferably 10 to 100 μm, more preferably 10 to 50 μm. If the volume average particle size of the plate-like filler is too small, the molded product tends to warp, and if too large, the melt flowability of the liquid crystal polyester composition becomes insufficient. The volume average particle diameter of the plate-like filler can be measured by a laser diffraction method.

  The compounding amount of the plate-like filler is preferably 5 to 80 parts by mass, more preferably 30 to 70 parts by mass with respect to 100 parts by mass of the liquid crystalline polyester. When the blending amount of the plate-like filler is too small, the molded body is likely to warp, and when it is too large, the melt flowability of the liquid crystal polyester composition becomes insufficient.

  The granular filler is a filler having a spherical shape or other shapes other than the fiber shape and the plate shape. As the granular filler, an inorganic filler is usually used. Examples of the particulate inorganic filler include silica, alumina, titanium oxide, glass beads, glass balloons, boron nitride, silicon carbide and calcium carbonate. Of these, glass beads are preferable. Two or more kinds of the granular fillers may be used as necessary.

  The volume average particle diameter of the granular filler is preferably 10 to 100 μm, more preferably 10 to 50 μm. If the volume average particle size of the granular filler is too small, the molded product tends to warp, and if too large, the melt flowability of the liquid crystal polyester composition becomes insufficient. The volume average particle diameter of the granular filler can be measured by a laser diffraction method.

  The amount of the granular filler is preferably 5 to 80 parts by mass, more preferably 30 to 70 parts by mass with respect to 100 parts by mass of the liquid crystalline polyester. If the blending amount of the granular filler is too small, the molded body is likely to warp, and if too large, the melt flowability of the liquid crystal polyester composition becomes insufficient.

  In the present invention, a liquid crystal polyester composition comprising liquid crystal polyester, fibrous filler, plate-like filler, and granular filler is provided in order from the upstream side to the cylinder, the screw disposed in the cylinder, and the cylinder. This is performed using an extruder having a first supply unit, a second supply unit, and a third supply unit. Then, while rotating the screw, the liquid crystal polyester is supplied to the cylinder from the first supply unit, the fibrous filler and the plate-like filler are supplied from the second supply unit, and the granular filler is supplied from the third supply unit. Then, the liquid crystal polyester, fibrous filler, plate-like filler and granular filler supplied into these cylinders are melt-kneaded and extruded. Thereby, the biting of the liquid crystal polyester and each filler into the screw is stabilized, the variation of the composition is prevented, the discharge unevenness and the strand breakage are prevented, and thus the liquid crystal polyester composition is stably manufactured with high productivity. be able to.

  Here, each filler is supplied from the second supply part or the third supply part located downstream of the first supply part to which the liquid crystalline polyester is supplied. The cylinder is supplied from the first supply part and kneaded. The liquid crystal polyester that advances inside is in a molten or semi-molten state at the positions of the second supply portion and the third supply portion, and by supplying each filler here, it becomes easy to knead, and the liquid crystal of each filler It is because the dispersibility to polyester improves. In addition, it is the same for the fibrous filler and / or the plate-like filler and the granular filler that the respective fillers are not supplied from the same supply unit, but are supplied from the second supply unit and the third supply unit. If it is supplied from the supply section, it is easy to cause a failure in biting of the fibrous filler and / or the plate-like filler, in particular, a failure to bite in the plate-like filler, and a variation in composition tends to occur. This is because it is advantageous to supply the granular filler from a supply unit different from the fibrous filler and the plate-like filler. In addition, the granular filler is supplied from the third supply unit located downstream of the second supply unit to which the fibrous filler and the plate-like filler are supplied. This is because it is easier to disperse in the liquid crystalline polyester than the shaped filler, and the kneading time, that is, the residence time in the cylinder may be short.

  FIG. 1 is a cross-sectional view schematically showing an example of an extruder used in the present invention. The extruder may be a short-screw extruder having one screw 6 or a twin-screw extruder having two screws 6, but a twin-screw extruder is preferable. The twin-screw extruder can be used in the same direction rotating from a single thread to a triple thread, and may be of a parallel shaft type, an oblique shaft type, or an incomplete meshing type rotating in different directions.

  The diameter of the screw 6 is preferably 50 mm or less, and more preferably 45 mm or less. Further, the ratio (L / D) of the total length (L) to the total width (D) of the cylinder 7 is preferably 50 or more, and more preferably 60 or more. When the diameter of the screw 6 is equal to or larger than the predetermined value and L / D is equal to or larger than the predetermined value, kneading can be sufficiently performed.

  The screw element that determines the screw design is usually composed of a transport element composed of forward flights, a plasticizing element, and a kneading element. In the case of a twin screw extruder, the plasticizing part and the kneading part are generally configured by combining screw elements such as reverse flight, seal ring, forward kneading disk, and reverse kneading disk. In FIG. 1, the screw 6 has a kneading disk 4a downstream of the first supply unit and upstream of the second supply unit, and kneading downstream of the second supply unit and upstream of the third supply unit. It has a disk 4b, and has a kneading disk 4c on the downstream side of the third supply section, so that kneading can be sufficiently performed.

  The motor 1 is connected to the screw 6 via the transmission 2. Thereby, the screw 6 can be rotationally driven by the motor 1, and the rotational speed can be adjusted by the transmission 2.

  The cylinder heater 8 is disposed so as to cover the outer surface of the cylinder 7 and is used to heat the inside of the cylinder 7. Examples of the cylinder heater 8 include an aluminum cast heater, a brass cast heater, a band heater, and a space heater. Moreover, you may comprise the heater 8 for cylinders by several heating components.

  The first supply unit 3a is provided near the upstream end of the cylinder 7, and the second supply unit 3b is provided upstream of the center between the first supply unit 3a and the downstream end of the cylinder 7. The third supply part 3c is preferably provided on the downstream side of the center between the first supply part 3a and the downstream end of the cylinder 7. In addition, these supply parts 3a, 3b, 3c are comprised from the supply port connected to a hopper and the cylinder 7, and the fixed_quantity | feed_rate feeder for supplying each raw material quantitatively to a hopper may be provided.

  The cylinder 7 may have a vent part. By depressurizing the vent portion, the inside of the cylinder 7 can be degassed under reduced pressure. Further, the vent portion may be used for the purpose of simply releasing the gas in the cylinder 7 into the atmosphere. In FIG. 1, the cylinder 7 has a vent portion 5a on the downstream side of the kneading disc 4a and on the upstream side of the second supply portion 3b, and on the downstream side of the kneading disc 4b on the upstream side of the third supply portion 3c. The vent portion 5b is provided on the downstream side of the kneading disk 4c, so that deaeration can be sufficiently performed.

  The opening length of the vent portion is preferably 0.5 to 5 times the diameter of the screw 6. If the opening length of the vent part is too small, the deaeration effect is insufficient, and if it is too large, foreign matter is mixed in from the vent part, venting up (the molten resin rises from the vent part), There is a risk that the conveying and kneading ability may decrease.

  The opening width of the vent portion is preferably 0.3 to 1.5 times the diameter of the screw 6. If the opening width of the vent part is too small, the deaeration effect is insufficient, and if it is too large, foreign matter is mixed in from the vent part, venting up (the molten resin rises from the vent part), or conveyance The kneading ability may be reduced.

  The pressure reduction of the vent part is usually performed using a pump, and examples thereof include a water ring pump, a rotary pump, an oil diffusion pump, and a turbo pump.

  A die 9 is disposed at the downstream end of the cylinder 7, and this die 9 has a nozzle 11 for extruding the composition. The die 9 is heated by a die heater 10.

  The cylinder 7 is heated to about 50 ° C. by the cylinder heating heater, the die 9 is heated by the die heating heater 10, the motor 1 is driven, and the screw 6 is rotated. 7, liquid crystal polyester is supplied from the first supply unit 3 a, fibrous filler and plate-like filler are supplied from the second supply unit 3 b, and granular filler is supplied from the third supply unit. After melt-kneading, a strand of the composition is extruded from the nozzle 11 of the die 9.

  If necessary, a part of the liquid crystalline polyester is supplied from the second supply part 3b and / or the third supply part 3c, or a part of the fibrous filler is supplied to the first supply part 3a and / or the third supply. A part of the plate-like filler is supplied from the first supply part 3a and / or the third supply part 3c, and a part of the granular filler is supplied from the first supply part 3a and / or the second part. Although it may supply from the supply part 3b, it is preferable to supply 80 mass% or more of liquid supply polyester from the 1st supply part 3a, and a fibrous filler is 80 mass of the total supply amount. % Or more is preferably supplied from the second supply unit 3b, and the plate-like filler is preferably supplied from the second supply unit 3b at 80% by mass or more of the total supply amount, and the granular filler is supplied from the total supply amount. It is preferable to supply 80% by mass or more from the third supply unit 3c.

  The strand of the composition extruded from the nozzle 11 is cut and processed into a pellet-shaped granulated product. In cutting the strand, the strand may be solidified in advance by air cooling or water cooling. As a cutter used for cutting, a cutter formed by combining a rotary blade and a fixed blade is generally used.

  As a molding method of the composition thus obtained, a melt molding method is preferable, and examples thereof include an injection molding method, an extrusion molding method such as a T-die method and an inflation method, a compression molding method, a blow molding method, a vacuum molding method, and the like. Although press molding is mentioned, in the present invention, an injection molding method is advantageously employed in order to make use of the effect of improving the weld strength.

  Examples of products and parts that are molded products of liquid crystal polyester compositions include: bobbins such as optical pickup bobbins and transbobbins; relay parts such as relay cases, relay bases, relay sprues, and relay armatures; RIMM, DDR, S / O, DIMM, Board to Board connector, FPC connector, card connector, CPU socket, etc .; lamp reflector, LED reflector, etc .; lamp holder, heater holder, etc .; speaker diaphragm, etc .; Separation claws, separation claws for printers, etc .; camera module parts; switch parts; motor parts; sensor parts; hard disk drive parts; tableware such as ovenware; And a sealing member such as a coil sealing member.

[Measurement of flow start temperature of liquid crystalline polyester]
Using a flow tester (“CFT-500 type” manufactured by Shimadzu Corporation), about 2 g of liquid crystalline polyester was filled into a cylinder attached with a die having a nozzle having an inner diameter of 1 mm and a length of 10 mm, and 9.8 MPa (100 kg). The liquid crystalline polyester was melted while being heated at a rate of 4 ° C./min under a load of / cm ² ), extruded from a nozzle, and a temperature showing a viscosity of 4800 Pa · s (48000 poise) was measured.

[Production of Liquid Crystalline Polyester (1)]
In a reactor equipped with a stirrer, a torque meter, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 994.5 g (7.2 mol) of p-hydroxybenzoic acid and 299.0 g (1.8 mol) of terephthalic acid , 99.7 g (0.6 mol) of isophthalic acid, 446.9 g (2.4 mol) of 4,4′-dihydroxybiphenyl, and 1347.6 g (13.2 mol) of acetic anhydride, and the gas in the reactor was charged. After substituting with nitrogen gas, 0.18 g of 1-methylimidazole was added, the temperature was raised from room temperature to 150 ° C. over 30 minutes with stirring in a nitrogen gas stream, and the mixture was refluxed at 150 ° C. for 30 minutes. Next, 2.4 g of 1-methylimidazole was added and the temperature was raised from 150 ° C. to 320 ° C. over 2 hours and 50 minutes while distilling out by-product acetic acid and unreacted acetic anhydride, and an increase in torque was observed. At that time, the contents were removed from the reactor and cooled to room temperature. The obtained solid was pulverized by a pulverizer, heated from room temperature to 250 ° C. over 1 hour in a nitrogen atmosphere, heated from 250 ° C. to 295 ° C. over 5 hours, and heated at 295 ° C. for 3 hours. By holding, after carrying out solid phase polymerization, it cooled and obtained powdery liquid crystalline polyester (1). The liquid crystal polyester (1) had a flow start temperature of 327 ° C.

[Production of liquid crystal polyester (2)]
In a reactor equipped with a stirrer, a torque meter, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 994.5 g (7.2 mol) of p-hydroxybenzoic acid and 239.2 g (1.44 mol) of terephthalic acid , 159.5 g (0.96 mol) of isophthalic acid, 446.9 g (2.4 mol) of 4,4′-dihydroxybiphenyl, and 1347.6 g (13.2 mol) of acetic anhydride, and the gas in the reactor was charged. After substituting with nitrogen gas, 0.18 g of 1-methylimidazole was added, the temperature was raised from room temperature to 150 ° C. over 30 minutes with stirring in a nitrogen gas stream, and the mixture was refluxed at 150 ° C. for 30 minutes. Next, 2.4 g of 1-methylimidazole was added and the temperature was raised from 150 ° C. to 320 ° C. over 2 hours and 50 minutes while distilling out by-product acetic acid and unreacted acetic anhydride, and an increase in torque was observed. At that time, the contents were removed from the reactor and cooled to room temperature. The obtained solid was pulverized by a pulverizer, heated from room temperature to 220 ° C. over 1 hour in a nitrogen atmosphere, heated from 220 ° C. to 240 ° C. over 30 minutes, and then at 240 ° C. for 10 hours. By holding, after carrying out solid-phase polymerization, it cooled and obtained powdery liquid crystal polyester (2). The liquid crystal polyester (2) had a flow start temperature of 286 ° C.

[Filler]
As the fibrous filler, glass fiber (“CS03JAPX-1” of Owens Corning Japan Co., Ltd .: number average fiber diameter 10 μm, number average fiber length 3 mm, number average aspect ratio 300) was used. As the plate-like filler, talc (“MS-KY” of Nippon Talc Co., Ltd .: volume average particle size 14.2 μm) was used. As the granular filler, glass beads (“EGB731” from Potters Barotini Co., Ltd .: volume average particle size 18 μm) were used.

Example 1
As the extruder, a twin-screw extruder having a screw diameter of 41 mm and a cylinder L / D of 62 was used. The cylinder is composed of 15 barrels, the first supply section is provided in the first barrel from the upstream side, the second supply section is provided in the sixth barrel from the upstream side, and the eighth barrel from the upstream side. Is provided with an open vent part (atmospheric pressure release), a third supply part is provided in the 10th barrel from the upstream side, and a decompression vent part (gauge pressure -0.08 MPa) is provided in the 14th barrel from the upstream side. It was.

  In the cylinder of the twin screw extruder, 55 parts by mass of liquid crystal polyester (1) and 45 parts by mass of liquid crystal polyester (2) are supplied from the first supply part, and 37.5 parts by mass of glass fiber and 62.5 parts by mass of talc. A strand-like liquid crystal polyester composition was manufactured by supplying from the second supply unit, supplying 50 parts by mass of glass beads from the third supply unit, and melt-kneading and extruding at a cylinder temperature of 340 ° C. At that time, no unevenness or cut in the thickness of the strand was observed.

Comparative Example 1
A strand-like liquid crystal polyester composition was produced in the same manner as in Example 1 except that glass beads were supplied from the second supply unit and glass fibers were supplied from the third supply unit. At that time, unevenness and cuts in the thickness of the strands were observed.

  DESCRIPTION OF SYMBOLS 1 ... Motor, 2 ... Transmission, 3a ... 1st supply part, 3b ... 2nd supply part, 3c ... 3rd supply part, 4a, 4b, 4c ... Kneading Discs, 5a, 5b, 5c ... vent part, 6 ... screw, 7 ... cylinder, 8 ... cylinder heater, 9 ... dice, 10 ... die heater, 11 ... ·nozzle.

Claims (13)

  Using an extruder having a cylinder, a screw disposed in the cylinder, and a first supply unit, a second supply unit, and a third supply unit provided in order from the upstream side of the cylinder, the screw is rotated. In the cylinder, liquid crystal polyester is supplied from the first supply unit, fibrous filler and plate-like filler are supplied from the second supply unit, and granular filler is supplied from the third supply unit. A method for producing a liquid crystal polyester composition, wherein the liquid crystal polyester, the fibrous filler, the plate filler and the granular filler are melt-kneaded and extruded. The liquid crystalline polyester is a liquid crystalline polyester having a repeating unit represented by the following formula (1), a repeating unit represented by the following formula (2), and a repeating unit represented by the following formula (3). Item 2. A method for producing a liquid crystal polyester composition according to Item 1.
(1) —O—Ar ¹ —CO—
(2) —CO—Ar ² —CO—
⁽³⁾ -X-Ar 3 -Y-
(Ar ¹ represents a phenylene group, a naphthylene group, or a biphenylylene group. Ar ² and Ar ³ each independently represent a phenylene group, a naphthylene group, a biphenylylene group, or a group represented by the following formula (4). X And Y each independently represents an oxygen atom or an imino group (—NH—), and each hydrogen atom in the group represented by Ar ¹ , Ar ² or Ar ³ independently represents a halogen atom or an alkyl group. Alternatively, it may be substituted with an aryl group.)
(4) -Ar ⁴ -Z-Ar ^5-
(Ar ⁴ and Ar ⁵ each independently represent a phenylene group or a naphthylene group. Z represents an oxygen atom, a sulfur atom, a carbonyl group, a sulfonyl group, or an alkylidene group.) Ar ¹ is a p-phenylene group or a 2,6-naphthylene group, Ar ² is a p-phenylene group, an m-phenylene group or a 2,6-naphthalenediyl group, and Ar ³ is a p-phenylene group or 4, The method for producing a liquid crystal polyester composition according to claim 2, which is a 4'-biphenylylene group, and X and Y are each an oxygen atom.   The liquid crystal polyester has a repeating unit represented by the formula (1) of 30 to 80 mol% and a repeating unit represented by the formula (2) of 10 to 10% based on the total amount of all repeating units constituting the liquid crystalline polyester. The method for producing a liquid crystal polyester composition according to claim 2 or 3, wherein the liquid crystal polyester has 35 mol% and 10 to 35 mol% of a repeating unit represented by the formula (3).   The method for producing a liquid crystal polyester composition according to any one of claims 1 to 4, wherein the fibrous filler is a glass fiber.   The number average fiber diameter of the said fibrous filler is 5-20 micrometers, and the number average aspect-ratio of the said fibrous filler is 20-500, The manufacture of the liquid crystalline polyester composition in any one of Claims 1-5. Method.   The method for producing a liquid crystal polyester composition according to any one of claims 1 to 6, wherein a supply amount of the fibrous filler is 5 to 80 parts by mass with respect to 100 parts by mass of the liquid crystal polyester.   The method for producing a liquid crystal polyester composition according to any one of claims 1 to 7, wherein the plate-like filler is talc and / or mica.   The method for producing a liquid crystal polyester composition according to claim 1, wherein the plate-like filler has a volume average particle size of 10 to 100 μm.   The method for producing a liquid crystal polyester composition according to claim 1, wherein a supply amount of the plate-like filler is 5 to 80 parts by mass with respect to 100 parts by mass of the liquid crystal polyester.   The method for producing a liquid crystal polyester composition according to claim 1, wherein the granular filler is a glass bead.   The method for producing a liquid crystal polyester composition according to claim 1, wherein the granular filler has a volume average particle size of 10 to 100 μm.   The method for producing a liquid crystal polyester composition according to any one of claims 1 to 12, wherein a supply amount of the granular filler is 5 to 80 parts by mass with respect to 100 parts by mass of the liquid crystal polyester.

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