JPH0853605A - Resin composition and production thereof - Google Patents

Abstract

PURPOSE:To obtain a resin composition excellent in color tone residence stability, and heat resistance and satisfactory in mechanical properties and molding appearance by incorporating a specific phosphoric acid compound into a liquid- crystal polyester or liquid-crystal polyester-amide. CONSTITUTION:The composition comprises 100 pts.wt. liquid-crystal polyester and/or liquid-crystal polyester-amide and 0.001-5 pts.wt. at least one compound selected from among phosphorous acid, hydrophosphorous acid, and metal salts of these. For further improving residence stability, another metal salt (e.g., potassium sulfate, potassium acetate, or barium acetate) may be incorporated in an amount of about 0.001-5 pts.wt. For imparting flame retardancy to the composition, an organobromine compound can be incorporated in an amount of about 0.5-30 pts.wt.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having excellent color tone, excellent retention stability, excellent mechanical properties and appearance of a molded article, and excellent heat resistance, and a method for producing the same. .

[0002]

2. Description of the Related Art In recent years, demands for higher performance of plastics have been increasing, and many polymers having various new properties have been developed and put on the market. Among them, optics characterized by parallel arrangement of molecular chains Anisotropic liquid crystal polymers are drawing attention because they have excellent moldability and mechanical properties, and their applications are expanding to mechanical parts, electric / electronic parts, and the like.

As the liquid crystal polymer, for example, a liquid crystal polymer obtained by copolymerizing p-hydroxybenzoic acid with 4,4'-dihydroxybiphenyl, terephthalic acid and isophthalic acid (JP-B-57-24407 and JP-A-60-25046). Gazette), 6-hydroxy-2 in p-hydroxybenzoic acid
Liquid crystal polymer copolymerized with naphthoic acid (Japanese Patent Laid-Open No. 54-7
No. 7691) is known.

Further, a liquid crystal polymer obtained by copolymerizing p-hydroxybenzoic acid and polyethylene terephthalate (Japanese Patent Publication No.
6-18016) and p-hydroxybenzoic acid and 4,4'-dihydroxybiphenyl, t-butylhydroquinone and terephthalic acid are copolymerized (JP-A-62-164719).

However, since these have higher melting points than general polyesters such as polyethylene terephthalate and polybutylene terephthalate, there is a problem that they are colored during polymerization and molding, or they are deteriorated by heat and mechanical properties are deteriorated. It was As a countermeasure, JP-A-2-515
No. 24 proposes a method for improving long-term heat resistance by adding a heat-resistant agent such as an organic phosphorus compound or hindered phenol during polymerization.

[0006]

SUMMARY OF THE INVENTION However, Japanese Patent Laid-Open No.
It has been found that the heat-resistant agent described in Japanese Patent No. 51524 does not always have sufficient effect on the thermal stability at the time of retention and the prevention of coloration. Therefore, the present invention solves the above problems,
An object of the present invention is to obtain a resin composition having excellent color tone, excellent retention stability, excellent mechanical properties and excellent appearance of heat-resistant molded articles.

[0007]

That is, the present invention is based on (A) 100 parts by weight of liquid crystal polyester and / or liquid crystal polyester amide, and (B) is selected from phosphorous acid, hypophosphorous acid and metal salts thereof. At least 1
The present invention provides a resin composition containing 0.001 to 5 parts by weight of one or more compounds.

The liquid crystalline polyester used in the present invention comprises a structural unit selected from aromatic oxycarbonyl units, aromatic dioxy units, aromatic dicarbonyl units, ethylenedioxy units, etc., and forms an anisotropic melt phase. Polyester to be mentioned, as the liquid crystal polyesteramide as the above structural unit and an aromatic iminocarbonyl unit,
Examples thereof include polyester amides having a structural unit selected from aromatic diimino units and aromatic iminooxy units and forming an anisotropic melt phase. Among them, those containing ethylenedioxy units are preferable.

Liquid crystalline polyester used in the present invention and /
Alternatively, the melting point of the liquid crystal polyester amide is preferably 300 ° C. or higher and 350 ° C. or lower.

Particularly, polyesters having the following structural units (I), (III), (IV) or (I), (II), (III) and (IV) are preferred, and (I), (II ), (III), (IV)
Polyesters consisting of are preferred.

[0011]

[Chemical 4] (However, R ₁ in the formula is

[Chemical 5] R ₁ represents one or more groups selected from

[Chemical 6] Represents one or more groups selected from In the formula, X represents a hydrogen atom or a chlorine atom, and the structural unit [(II) + (III)]
And the structural units (IV) are substantially equimolar. )

The structural unit (I) is a structural unit of polyester produced from p-hydroxybenzoic acid, and the structural unit (II) is 4,4'-dihydroxybiphenyl, 3,3.
′, 5,5′-Tetramethyl-4,4′-dihydroxybiphenyl, hydroquinone, t-butylhydroquinone, phenylhydroquinone, methylhydroquinone,
A structural unit produced from an aromatic dihydroxy compound selected from 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,2-bis (4-hydroxyphenyl) propane and 4,4′-dihydroxydiphenyl ether is represented by The unit (III) is a structural unit formed from ethylene glycol, and the structural unit (IV) is terephthalic acid, isophthalic acid, 4,4′-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-bis (phenoxy). ) Ethane-4,4'-dicarboxylic acid, 1,
2-bis (2-chlorophenoxy) ethane-4,4'-
Structural units formed from an aromatic dicarboxylic acid selected from dicarboxylic acid and diphenyl ether dicarboxylic acid are shown below. Of these, R ₁

[Chemical 7] And R ₂ is

Embedded image Are particularly preferred. As the liquid crystal polyesteramide, a liquid crystal polyesteramide containing a p-iminophenoxy unit formed from p-aminophenol in addition to the above structural units (I) to (IV) is preferable.

The above structural units (I), (II), (III) and (I
The copolymerization amount of V) is arbitrary. However, from the viewpoint of fluidity, the following copolymerization amount is preferable.

That is, the above structural units (I), (III) and (I
In the case of a copolymer comprising V), the structural unit (I) is preferably 30 to 95 mol% of [(I) + (III)],
˜95 mol% is more preferred. Further, the structural unit (IV) is substantially equimolar to the structural unit (III).

The above structural units (I), (II), (III),
In the case of a copolymer composed of (IV), the structural unit [(I) + (II)] is [(I) + (II) + (III) in view of heat resistance, flame retardancy and mechanical properties. Is preferably 60 to 95 mol%, and more preferably 85 to 93 mol%. Also, the structural unit
(III) is preferably 40 to 5 mol% of [(I) + (II) + (III)], and more preferably 15 to 7 mol%. The molar ratio of structural unit (I) / (II) is preferably 75/25 to 95/5, more preferably 78/22 to 93/7 from the viewpoint of the balance between heat resistance and fluidity. Also, the structural unit (I
V) is substantially equimolar to the structural unit [(II) + (III)].

In addition to the components constituting the above structural units (I) to (IV), aromatic dicarboxylic acids such as 3,3'-diphenyldicarboxylic acid and 2,2'-diphenyldicarboxylic acid, adipic acid, azelaic acid, sebacine Acids, aliphatic dicarboxylic acids such as dodecanedioic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, chlorohydroquinone,
4,4'-dihydroxydiphenyl sulfone, 4,4 '
-Aromatic diols such as dihydroxydiphenyl sulfide and 4,4'-dihydroxybenzophenone, 1,4-
Butanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanediol,
Aliphatic and alicyclic diols such as 1,4-cyclohexanedimethanol and aromatic hydroxycarboxylic acids such as m-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid, and p-aminophenol and p-aminobenzoic acid Further copolymerization can be carried out in a small proportion within a range that does not impair the object of the present invention.

Liquid crystalline polyester and / or used in the present invention
Alternatively, the method for producing the liquid crystal polyesteramide is not particularly limited, and can be produced according to a known polyester polycondensation method.

For example, in the production of the above-mentioned preferably used liquid crystal polyester, the following production method is preferably exemplified.

(1) p-acetoxybenzoic acid, 4,4 '
-Diacylated aromatic dihydroxy compounds such as diacetoxybiphenyl and diacetoxybenzene, aromatic dicarboxylic acids such as terephthalic acid, and polyester polymers such as polyethylene terephthalate, oligomers, and aromatics such as bis (β-hydroxyethyl) terephthalate A method for producing a bis (β-hydroxyethyl) ester of a dicarboxylic acid group by a deacetic acid polycondensation reaction.

(2) p-hydroxybenzoic acid, 4,4 '
-Aromatic dihydroxy compounds such as dihydroxybiphenyl and hydroquinone, aromatic dicarboxylic acids such as acetic anhydride and terephthalic acid, polyester polymers such as polyethylene terephthalate, oligomers or aromatic dicarboxylic acids such as bis (β-hydroxyethyl) terephthalate And a bis (β-hydroxyethyl) ester of the above are produced by deacetic acid polycondensation reaction.

As the catalyst used in the polycondensation reaction, known catalysts for polymerization of liquid crystal polyesters and liquid crystal polyester amides can be used.

Liquid crystalline polyester and / or used in the present invention
Alternatively, some liquid crystal polyesteramides can be used to measure the logarithmic viscosity in pentafluorophenol, in which case the value measured at 60 ° C. at a concentration of 0.1 g / dl is preferably 0.3 or more, 0.5-3.0 dl / g
Is particularly preferable.

Further, the melt viscosity of the liquid crystal polyester and / or liquid crystal polyesteramide in the present invention is 10
~ 20,000 poises are preferred, especially 20 ~ 10,0
00 poise is more preferred.

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

Here, the melting point (Tm) is the endothermic peak temperature (T) observed when the polymerization-completed polymer is measured at a temperature rising condition from room temperature to 20 ° C./min in the differential calorimetric measurement.
After the observation of m1), the temperature was maintained at Tm1 + 20 ° C for 5 minutes, then once cooled to room temperature under the temperature lowering condition of 20 ° C / min, and then measured again under the temperature rising condition of 20 ° C / min. Refers to the endothermic peak temperature (Tm2).

In the present invention, the component (B) is at least one compound selected from phosphorous acid, hypophosphorous acid and metal salts thereof, wherein the metal salt of phosphorous acid and the metal salt of hypophosphorous acid are It is preferably used. Of these, metal hypophosphite is preferably used. On the other hand, for metal species of metal phosphite and metal hypophosphite, alkali metals such as lithium, sodium and potassium, alkaline earth metals such as magnesium, calcium and barium are preferable, and alkaline earth metals are more preferable. Is. More specifically, examples include calcium hypophosphite, magnesium hypophosphite, barium hypophosphite, sodium hypophosphite, potassium hypophosphite, and the like.

The component (B) is added in an amount of 0.001 to 5 parts by weight, preferably 0.01 to 3 parts by weight, based on 100 parts by weight of the liquid crystal polyester. The effect of improving the properties is insufficient, and if it is more than 5 parts by weight, mechanical properties are deteriorated, which is not preferable.

The component (B) may be added at any time, either before or after the completion of the polymerization, or may be added in a plurality of divided portions before and after the completion of the polymerization. Specifically, it can be added to the reaction product before or after the completion of the polymerization, and after the polymerized liquid crystal polyester and / or liquid crystal polyester amide is taken out from the reaction vessel (B).
It is also possible to add components and melt-knead. A known method can be used for melt-kneading, for example, using a Banbury mixer, a rubber roll machine, a kneader, a single-screw or twin-screw extruder, and the like, and melt-kneading at a temperature of 200 to 370 ° C. to obtain a composition. You can

The component (B) can be added as a solid or as a liquid at a temperature above the melting point of the component (B). When the compounding is carried out at a low temperature, the component (B) can be added as a solution.

In the present invention, a metal salt other than (C) phosphorous acid and hypophosphorous acid can be added to further improve the retention stability. As the metal salt other than phosphorous acid and hypophosphorous acid, organic or inorganic ones can be used, but sulfuric acid, hydrogen halide, nitric acid, boric acid,
It is preferable to use an alkali metal salt such as phosphoric acid, pyrophosphoric acid, acetic acid, oxalic acid or benzoic acid, or an alkaline earth metal salt. More specifically, metal salts such as potassium sulfate, sodium acetate, barium acetate, magnesium acetate, sodium benzoate, and sodium hydrogen phosphate can be used.

The addition amount of the metal salt other than phosphorous acid and hypophosphorous acid is 0.001 to 5 parts by weight, preferably 0.01 to 3 parts by weight, per 100 parts by weight of the liquid crystal polyester.

The metal salt other than (C) phosphorous acid and hypophosphorous acid can be added as a solid or as a liquid at a temperature above its melting point. When the compounding is carried out at a low temperature, it can be added as a solution.

In the present invention, an organic bromine compound (D) may be further added for the purpose of imparting flame retardancy.
The organic bromine compound has a bromine atom in the molecule, and it is particularly preferable that the bromine compound has a bromine content of 20% by weight or more. Specifically, low molecular weight organic bromine compounds such as decabromodiphenyl ether, ethylene bis- (tetrabromophthalimide), brominated polycarbonate (for example, a polycarbonate oligomer produced from brominated bisphenol A as a raw material or its copolymerization with bisphenol A). Products), brominated epoxy compounds (for example, diepoxy compounds produced by the reaction of brominated bisphenol A with epichlorohydrin, monoepoxy compounds obtained by the reaction of brominated phenols with epichlorohydrin), poly (brominated benzyl acrylate), Brominated polyphenylene ether, brominated bisphenol A, condensate of cyanuric chloride and brominated phenol, brominated polystyrene, crosslinked brominated polystyrene, crosslinked brominated poly α-methylstyrene And halogenated polymers and oligomers thereof, or mixtures thereof. Among them, ethylene bis- (tetrabromophthalimide), brominated epoxy oligomer or polymer, brominated polystyrene, crosslinked brominated polystyrene, brominated polyphenylene ether and bromine. Brominated polycarbonate is preferable, and ethylene bis- (tetrabromophthalimide), brominated polystyrene, and brominated polycarbonate can be particularly preferably used. The above preferable organic bromine compound will be described in more detail. As the brominated epoxy polymer, those represented by the following general formula (a) are preferable.

[0034]

[Chemical 9] The polymerization degree n in the general formula (a) is preferably 15 or more,
More preferably, it is 50-80. Further, as the brominated polystyrene, one represented by the following formula (b) having a weight average molecular weight of 1 × 10 ^{3 to} 3 × 10 ⁵ produced by brominating polystyrene obtained by radical polymerization or anionic polymerization, or Examples thereof include polybrominated styrene having a brominated styrene unit represented by the formula (b) or (c) produced by radical polymerization or anionic polymerization, preferably radical polymerization of a brominated styrene monomer, and especially brominated styrene. Weight average molecular weight 1 × 10 ^{3 to} 3 × 10 ⁵ containing a structural unit represented by the following formula (c), which is produced from a monomer, as a main constituent
Of polybrominated styrene are preferred.

[0035]

[Chemical 10] Brominated styrene monomer here means styrene monomer 1
It is preferable that about 2 bromine atoms are introduced into the aromatic ring per one by a substitution reaction, and monobrominated styrene, tribrominated styrene and the like may be contained in addition to dibrominated styrene. The polybrominated styrene preferably contains dibrominated styrene units in an amount of 60% by weight or more.
Those containing 0% by weight or more are more preferable. In addition to dibrominated styrene, 40% by weight or less of monobrominated styrene and / or tribrominated styrene, preferably 30% by weight
The following may be copolymerized polybrominated styrene. The weight average molecular weight of this polybrominated styrene is 1 × 10 ³ to
3 × 10 ⁵ is preferable, and 1 × 10 ^{4 to} 1.5
× 10 ⁵ is more preferable. The weight average molecular weight is a value measured using a gel permeation chromatograph and is a relative value based on polystyrene molecular weight. The cross-linked brominated polystyrene is preferably polystyrene obtained by brominated porous polystyrene cross-linked with diphenylbenzene. As the brominated polycarbonate, those represented by the following general formula (d) are preferable.

[0036]

[Chemical 11] (R ₃ and R _{4 each} represent a substituted or unsubstituted aryl group, and a pt-phenyl group is most preferable.) The polymerization degree n in the above formula (d) is preferably 4 or more, and 8 or more. Especially, 8 to 25 can be used more preferably. The amount of the organic bromine compound (D) added is 0.5 to 30 parts by weight, preferably 1 to 20 parts by weight, per 100 parts by weight of the liquid crystal polyester.

The method of adding these is preferably melt kneading, and known methods can be used for melt kneading. For example, Banbury mixer, rubber roll machine,
Using a kneader, single-screw or twin-screw extruder, etc., 200
The composition can be obtained by melt-kneading at a temperature of ˜370 ° C.

Further, mechanical properties and heat resistance can be further improved by adding a reinforcing agent and a filler to the resin composition of the present invention.

When the reinforcing agent and the filler are added, the addition amount is preferably 200 parts by weight or less, and particularly preferably 15 to 150 parts by weight, relative to 100 parts by weight of the liquid crystal polyester.

Examples of the reinforcing agent and filler that can be used in the present invention are glass fiber, carbon fiber, aromatic polyamide fiber, potassium titanate fiber, gypsum fiber, brass fiber, stainless fiber, steel fiber, ceramic fiber, boron. Whisker fiber, asbestos fiber, graphite, mica, talc, silica, calcium carbonate, glass beads, glass flakes, glass microballoons,
Examples thereof include fibrous, powdery, granular or plate-like inorganic fillers such as clay, wollastonite, titanium oxide and molybdenum disulfide. Further, as these reinforcing agents and fillers, those treated with a coupling agent such as a silane type or titanate type, or other surface treatment agent may be used.

Furthermore, the resin composition of the present invention contains an antioxidant and a heat stabilizer (for example, hindered phenol, hydroquinone, and the like) to the extent that the object of the present invention is not impaired.
Phosphites and their substitution products), UV absorbers (eg resorcinol, salicylate, benzotriazole, benzophenone, etc.), lubricants and mold release agents (montanic acid and its salts, its esters, its half esters, stearyl alcohol) , Stearamide and polyethylene wax), dyes (eg nitrosine) and pigments (eg cadmium sulfide,
It is possible to add usual additives such as colorants containing phthalocyanine, carbon black, etc.), plasticizers, antistatic agents, and other thermoplastic resins to impart predetermined properties.

The method of adding these is preferably melt kneading, and known methods can be used for melt kneading. For example, Banbury mixer, rubber roll machine,
Using a kneader, single-screw or twin-screw extruder, etc., 200
The composition can be obtained by melt-kneading at a temperature of ˜370 ° C.

The resin composition thus obtained is injection molded,
It can be subjected to usual molding such as extrusion molding and compression molding, and is extremely useful as various molded products for electric / electronic parts, precision parts, automobile parts and the like. Further, since the color tone and the retention stability are excellent, an excellent colored molded product can be obtained by adding a colorant.

[0044]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1 p-Hydroxybenzoic acid 994 parts by weight, 4,4'-dihydroxybiphenyl 126 parts by weight, terephthalic acid 112
Parts by weight, 216 parts by weight of polyethylene terephthalate having an intrinsic viscosity of about 0.6 dl / g, 960 parts by weight of acetic anhydride, 1.3 parts by weight of phosphorous acid (0.1 parts by weight based on 100 parts by weight of liquid crystalline polyester). Was charged into a reaction vessel equipped with a stirring blade and a distillation tube, and deacetic acid polymerization was carried out under the following conditions.

First, 100 to 250 in a nitrogen gas atmosphere.
After reacting at 50 ° C for 5 hours and at 250 to 300 ° C for 1.5 hours, the pressure was reduced to 0.5 mmHg at 315 ° C for 1 hour, and further 1.
After reaction for 25 hours to complete the polycondensation, almost the theoretical amount of acetic acid was distilled off, and a liquid crystal polyester having the following theoretical structural formula was obtained.

[0047]

[Chemical 12] k / l / m / n = 80 / 7.5 / 12.5 / 20

The liquid crystal polyester was placed on a sample stand of a polarizing microscope and the temperature was raised to confirm the optical anisotropy. As a result, the liquid crystal starting temperature was 295 ° C., which showed good optical anisotropy. It was The melting point (Tm) was 316 ° C.
The logarithmic viscosity of this liquid crystalline polyester (measured in pentafluorophenol at a concentration of 0.1 g / dl at 60 ° C.) was 1.96 dl / g, at 326 ° C. and a shear rate of 1000.
The melt viscosity in 1 / sec was 800 poise. This is subjected to a Sumitomo Nestal injection molding machine Promat 40/25 (manufactured by Sumitomo Heavy Industries, Ltd.), kept at a cylinder temperature of 340 ° C. for 4 minutes and 30 minutes, and a bending test piece under a mold temperature of 90 ° C. (1/32 ″ × 1/2 ″ × 5 ″) was molded.
The whiteness (W value) of this test piece was measured using an SM color computer device manufactured by Suga Test Instruments Co., Ltd. Further, this test piece was dissolved in pentafluorophenol and the logarithmic viscosity (60 ° C. at a concentration of 0.1 g / dl) was measured. The results are shown together in Table 1.

Example 2 The same as Example 1 except that 1.3 parts by weight of calcium hypophosphite (0.1 parts by weight relative to 100 parts by weight of liquid crystal polyester) was added in place of phosphorous acid in Example 1. Deacetic acid polymerization was performed.

The liquid crystal starting temperature of this liquid crystal polyester is
The temperature was 294 ° C., indicating good optical anisotropy. The melting point (Tm) was 315 ° C. The logarithmic viscosity (measured in pentafluorophenol at a concentration of 0.1 g / dl at 60 ° C.) of this liquid crystalline polyester was 1.97 dl / g, and the melt viscosity at 325 ° C. and the shear rate of 1000 / sec was 7
It was 80 poise. Whiteness of this polyester (W
The value) and the logarithmic viscosity were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 3 Deacetic acid polymerization was carried out in the same manner as in Example 1 except that 1.3 parts by weight of potassium sulfate (0.1 parts by weight based on 100 parts by weight of liquid crystal polyester) was further added. went.

The liquid crystal starting temperature of this liquid crystal polyester is
The temperature was 293 ° C., indicating good optical anisotropy. The melting point (Tm) was 315 ° C. The logarithmic viscosity of this liquid crystalline polyester (measured in pentafluorophenol at a concentration of 0.1 g · dl at 60 ° C.) is 1.97 dl / g, and the melt viscosity at 325 ° C. and the shear rate of 1000 / sec is 7
It was 90 poise. Whiteness of this polyester (W
The value) and the logarithmic viscosity were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 Deacetic acid polymerization was carried out in the same manner as in Example 1 except that phosphorous acid was not added.

The liquid crystal starting temperature of this liquid crystal polyester is
The temperature was 293 ° C., indicating good optical anisotropy. The melting point (Tm) was 314 ° C. The logarithmic viscosity (measured at 60 ° C. in pentafluorophenol at a concentration of 0.1 g / dl) of this liquid crystalline polyester was 1.98 dl / g, and the melt viscosity at 324 ° C. and the shear rate of 1000 / sec was 7
It was 80 poise. Whiteness of this polyester (W
The value) and the logarithmic viscosity were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 2 Deacetic acid polymerization was carried out in the same manner as in Example 1 except that 1.3 parts by weight of triphenylphosphite was added instead of phosphorous acid.

The liquid crystal starting temperature of this liquid crystal polyester is
The temperature was 291 ° C., indicating good optical anisotropy. The melting point (Tm) was 315 ° C. The logarithmic viscosity of this liquid crystalline polyester (measured in pentafluorophenol at a concentration of 0.1 g / dl at 60 ° C.) was 1.94 dl / g, and the melt viscosity at 325 ° C. and the shear rate of 1000 / sec was 7
It was 40 poise. Whiteness of this polyester (W
The value) and the logarithmic viscosity were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 3 Deacetic acid polymerization was carried out in the same manner as in Example 1 except that 1.3 parts by weight of distearyl pentaerythrite diphosphite was added instead of phosphorous acid.

The liquid crystal starting temperature of this liquid crystal polyester is
The temperature was 290 ° C., indicating good optical anisotropy. The melting point (Tm) was 314 ° C. The logarithmic viscosity (measured in pentafluorophenol at a concentration of 0.1 g / dl at 60 ° C.) of this liquid crystalline polyester was 1.92 dl / g, and the melt viscosity at 324 ° C. and the shear rate of 1000 / sec was 7.
It was 50 poise. Whiteness of this polyester (W
The value) and the logarithmic viscosity were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0059]

[Table 1]

Example 4 To 100 parts by weight of the liquid crystalline polyester of Example 2, 10 parts by weight of polydibrominated styrene (bromine content 59%) obtained by polymerizing a dibrominated polystyrene monomer and an average diameter of 10 μm were used.
45 parts by weight of glass fiber having an average length of 3000 μm and a glass blender were mixed with a ribbon blender, melt-kneaded at 310 ° C. using a 30 mmφ twin-screw extruder, and then pelletized. This was subjected to a Sumitomo Nestal injection molding machine Promat 40/25 (manufactured by Sumitomo Heavy Industries, Ltd.) at a cylinder temperature of 340 ° C. for 4 hours.
For 30 minutes and 30 minutes, and a bending test piece (1/32 ″ × 1/2 ″ × 5 ″) was formed under the condition that the mold temperature was 90 ° C. The whiteness (W) was measured in the same manner as in Example 1. In addition, the test piece was dissolved in pentafluorophenol, the insoluble content was filtered, the concentration was adjusted to 0.1 g / dl, and the logarithmic viscosity was measured at 60 ° C. These results are also combined. It shows in Table 2.

Example 5 0.5 parts by weight of calcium hypophosphite, 10 parts by weight of the polydibrominated styrene used in Example 4, and 45 parts by weight of glass fiber were used with respect to 100 parts by weight of the liquid crystal polyester of Comparative Example 1. Melt kneading and molding as in Example 4, whiteness (W value)
And the logarithmic viscosity was measured. The results are shown in Table 2.

Comparative Example 4 Melt kneading and molding were carried out in the same manner as in Example 5 except that 1 part by weight of triphenylphosphite was added instead of calcium hypophosphite in Example 5, whiteness (W value) and logarithmic viscosity. Was measured. The results are shown in Table 2.

Comparative Example 5 Melt kneading and molding were carried out in the same manner as in Example 5 except that calcium hypophosphite was not added, and whiteness (W value) and logarithmic viscosity were measured. The results are shown in Table 2.

[0064]

[Table 2]

As is clear from the results shown in Tables 1 and 2,
The resin composition of the present invention has an excellent color tone, a small decrease in logarithmic viscosity during retention, and excellent retention stability. In addition, Example 3
It can be seen that the retention stability is further improved by adding a metal salt other than phosphorous acid and hypophosphorous acid metal salt, that is, potassium sulfate. On the other hand, as shown in Comparative Examples 2 to 4, those to which a phosphite compound other than those used in the present invention was added, or those to which nothing was added like Comparative Examples 1 and 5 were more stable in color tone and retention than those in Examples. It turns out that it is inferior in sex.

[0066]

INDUSTRIAL APPLICABILITY The present invention makes it possible to obtain a resin composition having excellent color tone, excellent retention stability, excellent mechanical properties and excellent appearance of heat-resistant molded articles.

Claims (7)

[Claims] 1. To (A) 100 parts by weight of liquid crystal polyester and / or liquid crystal polyester amide, (B) at least one compound selected from phosphorous acid, hypophosphorous acid and metal salts thereof is used. A resin composition containing 0.001 to 5 parts by weight. 2. The resin composition according to claim 1, further comprising (C).
Metal salts other than phosphorous acid and hypophosphorous acid metal salts 0.00
A resin composition containing 1 to 5 parts by weight. 3. A resin composition comprising the resin composition according to claim 1 or 2 further containing 0.5 to 30 parts by weight of (D) an organic bromine compound. 4. The resin composition according to claim 1, wherein the liquid crystal polyester and / or the liquid crystal polyester amide contains an ethylenedioxy unit as an essential component. 5. The liquid crystal polyester has the following structural unit (I)
, (II), (III) and (IV), the structural unit [(I)
+ (II)] is 60 to 95 mol% of [(I) + (II) + (III)], and the structural unit (III) is 40 to 40% of [(I) + (II) + (III)].
5 mol% and the molar ratio of structural units (I) / (II) is 75/2
It is 5-95 / 5, The resin composition of any one of Claims 1-3. Embedded image (However, R ₁ in the formula is It represents one or more groups selected from, R ₂ is ## STR3 ## And one or more groups selected from However, in the formula, X represents a hydrogen atom or a chlorine atom. Further, the structural unit (IV) is substantially equimolar to the structural unit [(II) + (III)]. ) 6. A liquid crystal polyester and / or a liquid crystal polyester amide (A) before completion of polymerization of (B) phosphorous acid,
0.001 to 5 parts by weight of at least one compound selected from hypophosphorous acid and metal salts thereof is added to 100 parts by weight of component (A), and a method for producing a resin composition. . 7. A liquid crystal polyester and / or a liquid crystal polyester amide after completion of polymerization of (A) phosphorous acid (B),
0.001 to 5 parts by weight of at least one compound selected from hypophosphorous acid and metal salts thereof is added to 100 parts by weight of component (A), and a method for producing a resin composition. .