JPH0632971A - Liquid crystal polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain a liquid crystal composition excellent in hydrolysis and heat resistances by incorporating a specified amount of a specified compound into a liquid crystal polyester resin that forms an anisotropic molten phase. CONSTITUTION:0.01-20 pts.wt. glycidylamine compound of formula I or II (wherein R is a divalent organic group; G is glycidyl; and R1 to R4 are each 1-4C alkyl or G, provided that at least two of them are G's) is incorporated into 100 pts.wt. liquid crystal polyester that forms an anisotropic molten phase (e.g. a polyester obtained by the deacetylation and polycondensation of p- hydroxybenzoic acid, 4,4'-dihydroxybiphenyl, acetic anhydride, terephthalic acid and polyethylene terephthalate).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel composition comprising a liquid crystal polyester having extremely high hydrolysis resistance and heat resistance represented by long-term aging characteristics and glycidyl amine.

[0002]

2. Description of the Related Art In recent years, the demand for higher performance of plastics has been increasing, and many polymers having various new properties have been developed. Among them, an optically anisotropic liquid crystal characterized by parallel arrangement of molecular chains. Attention has been paid to the fact that polymers have excellent fluidity and mechanical properties. However, it is known that the liquid crystal polymer has a low glass transition temperature, and therefore does not necessarily have sufficient hydrolysis resistance or long-term aging characteristics.

Therefore, it has been studied to add a glycidyl ether type or glycidyl ester type epoxy compound to the liquid crystal polyester to improve the hydrolysis resistance and heat resistance (Japanese Patent Laid-Open No. 14863/1993).

[0004]

However, when the above-mentioned epoxy compound is added, hydrolysis resistance and heat resistance are improved, but they are still not sufficiently satisfactory. An object of the present invention is to solve the above problems and obtain a liquid crystal polyester resin composition having excellent heat resistance.

[0005]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that the addition of a glycidylamine compound having two or more glycidyl groups to a liquid crystal polyester improves the heat resistance. Obviously, the present invention has been reached.

That is, in the present invention, 0.01 to 20 parts by weight of a glycidylamine compound represented by the following general formula (I) or (II) is added to 100 parts by weight of a liquid crystal polyester resin forming an anisotropic molten phase. The present invention provides a liquid crystal polyester resin composition added.

[0007]

[Chemical 5] (However, R represents a divalent organic group, R1 to R4 represent an alkyl group or a glycidyl group, but at least two represent a glycidyl group, and G represents a glycidyl group.)

The compounds specifically used in the present invention will be described in detail below. The liquid crystal polyester resin used in the present invention is a polyester that forms an anisotropic melt phase, and is p-
Hydroxybenzoic acid / polyethylene terephthalate liquid crystal polyester, p-hydroxybenzoic acid / 6-hydroxy-2-naphthoic acid liquid crystal polyester, p-hydroxybenzoic acid / 4,4′-dihydroxybiphenyl / terephthalic acid / isophthalic acid liquid crystal polyester The following structural units (III), (IV), (VI)
Liquid crystal polyesters consisting of or consisting of (III), (IV), (V) and (VI) are preferred.

[0009]

[Chemical 6]

(Where R1 is

[Chemical 7] R1 represents one or more groups selected from

[0011]

[Chemical 8] Represents one or more groups selected from

In the formula, X represents a hydrogen atom or a chlorine atom, and the structural unit [(IV) + (V)] and the structural unit (VI) are substantially equimolar. )

The above structural unit (III) is a structural unit of polyester produced from p-hydroxybenzoic acid, and the structural unit (IV) is 4,4'-dihydroxybiphenyl, 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,
Structural units produced from aromatic dihydroxy compounds selected from 4'-dihydroxydiphenyl ether, structural units (V) are structural units produced from ethylene glycol, structural units (VI) are terephthalic acid, isophthalic acid,
4,4'-diphenylcarboxylic 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,
Each of the structural units formed from an aromatic dicarboxylic acid selected from 4'-diphenyl ether dicarboxylic acid is shown.

Of these, particularly when the structural unit (V) is included, R1 is

[Chemical 9] Is 70% by mole or more of the structural unit (IV), R2
But

[0015]

[Chemical 10] Particularly preferably those which account for 70 mol% or more of the structural unit (VI).

The copolymerization amount of the above structural units (III), (IV), (V) and (VI) is arbitrary. However, from the viewpoint of fluidity, the following copolymerization amount is preferable. That is, when the structural unit (V) is included, the structural unit [(III) + (IV)] is [(III) + in view of heat resistance and mechanical properties.
60 to 95 mol% of (IV) + (V)] is preferable, and
5 to 92 mol% is more preferable. In addition, structural unit (V)
Is preferably 40 to 5 mol% of [(III) + (IV) + (V)], and more preferably 25 to 8 mol%. Also, the structural unit
The molar ratio of (III) / (IV) is preferably 75/25 to 95/5, and more preferably 78/22 to 93/7 from the viewpoint of the balance between fluidity and mechanical properties. The structural unit (VI) is substantially equimolar to the structural unit [(IV) + (V)].

On the other hand, when the structural unit (V) is not contained, the structural unit (III) is [(III) + in view of fluidity.
(IV)] is preferably 40 to 90 mol%, and 6
It is particularly preferably from 0 to 88 mol%, and the structural unit (VI) is substantially equimolar to the structural unit (IV).

In the condensation polymerization of the preferred liquid crystalline polyester, 3,3'-diphenyldicarboxylic acid, 2,3'-diphenyldicarboxylic acid, and 2, in addition to the components constituting the structural units (III) to (VI) are used.
Aromatic dicarboxylic acids such as 2'-diphenyldicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, alicyclic dicarboxylic acids such as hexahydroterephthalic acid, chlorohydroquinone, methylhydroquinone, Aromatic diols such as 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxydiphenyl sulfide and 4,4′-dihydroxybenzophenone, 1,4-butanediol, 1,6
-Hexanediol, neopentyl glycol, 1,4
Aliphatic and alicyclic diols such as cyclohexanediol and 1,4-cyclohexanedimethanol, and aromatic hydroxycarboxylic acids such as m-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid, and p-aminophenol, p-amino Benzoic acid or the like may be copolymerized in such an amount that the object of the present invention is not impaired.

The method for producing the liquid crystal polyester resin in the present invention is not particularly limited, and the liquid crystal polyester resin can be produced in accordance with a known polyester polycondensation method. For example, among the liquid crystal polyesters that can be preferably used, the production methods (1) to (4) are preferable when the structural unit (V) is not contained, and (5) is preferable when the structural unit (V) is contained.

(1) p-acetoxybenzoic acid and 4,
A method for producing a diacylated aromatic dihydroxy compound such as 4′-diacetoxybiphenyl or paraacetoxybenzene and an aromatic dicarboxylic acid such as terephthalic acid by a deacetic acid condensation polymerization reaction.

(2) p-hydroxybenzoic acid and 4,
A method in which an aromatic dihydroxy compound such as 4′-dihydroxybiphenyl or hydroquinone or an aromatic dicarboxylic acid such as terephthalic acid is reacted with acetic anhydride to acylate a phenolic hydroxyl group, and then a deacetic acid polycondensation reaction is performed.

(3) P-hydroxybenzoic acid phenyl ester and an aromatic dihydroxy compound such as 4,4'-dihydroxybiphenyl and hydroquinone and a diphenyl ester of an aromatic dicarboxylic acid such as terephthalic acid are produced by a dephenol polycondensation reaction. how to.

(4) Aromatic dicarboxylic acids such as p-hydroxybenzoic acid and terephthalic acid are reacted with a predetermined amount of diphenyl carbonate to form respective diphenyl esters, and then aromatic compounds such as 4,4'-dihydroxybiphenyl and hydroquinone. Add a group dihydroxy compound,
A method for producing by dephenolization polycondensation reaction.

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

Typical examples of the catalyst used in the polycondensation reaction include stannous acetate, tetrabutyl titanate, potassium acetate, antimony trioxide, metal compounds such as sodium acetate, magnesium and the like. It is effective when

The liquid crystal polyester resin used in the present invention is capable of measuring the logarithmic viscosity in pentafluorophenol, and in this case, the value measured at 60 ° C. at a concentration of 0.1 g / dl. It is preferably 0.5 or more, and particularly 1.0 when the structural unit (V) is included.
~ 3.0 dl / g is preferred.

The melt viscosity of the liquid crystal polyester resin used in the present invention is preferably 10 to 20,000 poise, and more preferably 20 to 10,000 poise. The melt viscosity is a value measured by a high pressure capillary viscometer at a liquid crystal starting temperature of + 30 ° C. and a shear rate of 1,000 / sec. The liquid crystal starting temperature is a temperature at which the liquid crystal is placed on a sample stand of a polarization microscope, heated to heat, and emits opalescence under shear stress.

The glycidylamine compound used in the present invention is a glycidylated primary or secondary amine and is not necessarily limited, but includes the following compounds.

[0029]

[Chemical 11] (In the formula, G represents a glycidyl group.)

Incidentally, other alkyl groups may be substituted on the aromatic ring of these compounds. These diglycidyl amine compounds may be used alone or in combination of two or more, or may be used in combination with a diepoxy compound having a structure other than the above.

The amount of the glycidylamine compound added to the composition of the present invention is 0.01 to 20 parts by weight, preferably 0.05 to 10 parts by weight, based on 100 parts by weight of the liquid crystal polyester resin. . If it is less than 0.01 parts by weight, the effect of improving heat resistance is small, and if it exceeds 20 parts by weight, the mechanical properties and fluidity of the liquid crystal polyester composition are greatly deteriorated, both of which are not preferable.

In producing the liquid crystal polyester resin composition of the present invention, conventionally known additives such as polyester polymerization catalysts, heat resistance agents, weather resistance agents, antistatic agents, dyes, colorants, crystal nucleating agents, flame retardants, etc. , Talc, clay, mica,
It is also possible to add inorganic fillers such as calcium metasilicate, silica sand, glass beads, glass flakes, potassium whisker titanate and gypsum fiber, and reinforcing agents such as glass fiber, asbestos fiber and carbon fiber.

As a method of mixing the liquid crystal polyester and the glycidyl amine compound, various methods can be applied. Examples of the apparatus for melt-mixing include a mixing roll, a Banbury mixer, a kneader, an extruder, and the like. Among them, an extruder is preferable. As the extruder, either a single screw or a screw having two or more screws can be used, but it is particularly preferable to use a twin screw extruder.

When a molded product is obtained from the resin composition of the present invention, ordinary methods such as injection molding, extrusion molding and blow molding can be applied, and the obtained molded product exhibits good performance.

[0035]

EXAMPLES The present invention will be described in more detail with reference to examples below, but these examples do not limit the scope of application of the present invention. In addition, the part in an Example represents a weight part.

[0036]

Reference Example 1 1105 parts by weight of p-hydroxybenzoic acid,
A reactor equipped with 140 parts by weight of 4,4′-dihydroxybiphenyl, 1067 parts by weight of acetic anhydride, 125 parts by weight of terephthalic acid and 240 parts by weight of polyethylene terephthalate having an intrinsic viscosity of about 0.6 dl / g, equipped with a stirring blade and a distillation tube. Then, deacetic acid polycondensation was carried out under the following reaction conditions.

First, 100 to 250 is applied in a nitrogen gas atmosphere.
The reaction was carried out at ℃ for 1.5 hours. Thereafter, the pressure was reduced to 0.5 mmHg in 315 ° C. for 1.5 hours, and the reaction was further continued for 1.0 hour to complete polycondensation. Almost the theoretical amount of acetic acid was distilled off to obtain a liquid crystal polyester having the following theoretical structural formula.

[0038]

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

The polyester was placed on a sample stage of a polarizing microscope and the temperature was raised to confirm the optical anisotropy. As a result, the liquid crystal starting temperature was 292 ° C., indicating good optical anisotropy. . Logarithmic viscosity of this polyester (0.1 g / d
(measured in pentafluorophenol at a concentration of 1 at 60 ° C.) was 1.96 dl / g, and the melt viscosity at 322 ° C. and a shear rate of 1000 / sec was 910 poise.

Examples 1 to 5 and Comparative Examples 1 to 3 The liquid crystal polyester polymerized in Reference Example 1 and the following epoxy compounds were weighed in predetermined amounts and dry blended. Three
Melt extruded with a 30 mmφ twin-screw extruder set at 20 ° C.,
After water cooling, it was pelletized. Also, using this dry pellet, an injection molding machine in which the cylinder temperature was 320 ° C. and the mold temperature was 80 ° C., the ASTM No. 1 dumbbell of ⅛ ″ thickness and ⅛ ″ × 1/2 ″ × 5 ″ were used. A test piece was molded.

The obtained ASTM No. 1 dumbbell was placed in a 3 liter pressure vessel containing ion-exchanged water. This pressure-resistant container was placed in a gear oven maintained at 80 ° C. and subjected to a hydrolysis resistance test for 70 days. Also, ASTM No. 1 dumbbell 190
It was placed in a gear oven maintained at 0 ° C. and subjected to a dry heat deterioration test for 70 days. The strength retention was calculated by setting the tensile strength of the untreated product to 100%. The results of these tests are shown in Table 1.

[0042]

[Chemical 13]

[0043]

[Table 1]

From the results shown in Table 1 above, it can be seen that the addition of the glycidylamine compound is superior in hydrolysis resistance and long-term aging characteristics to the case of adding other epoxy compounds.

[0045]

The liquid crystal polyester resin composition according to the present invention is excellent in hydrolysis resistance, heat resistance represented by long-term aging characteristics, and is exposed to high temperature and high humidity or high temperature mechanical parts, automobile parts, It is useful for applications such as sealing materials.

Claims (2)

[Claims] 1. A glycidylamine compound represented by the following general formula (I) or (II) with respect to 100 parts by weight of a liquid crystal polyester resin forming an anisotropic molten phase.
A liquid crystal polyester resin composition obtained by adding 0 part by weight. [Chemical 1] (However, R represents a divalent organic group, G represents a glycidyl group, and R1 to R4 represent an alkyl group or a glycidyl group, but at least two are glycidyl groups.) 2. A liquid crystal polyester resin comprising the following structural unit (II
I), (IV), (VI) or (III), (I
The liquid crystal polyester resin composition according to claim 1, which is a liquid crystal polyester resin forming an anisotropic molten phase composed of V), (V) and (VI). [Chemical 2] (However, in the formula, R1 is R1 represents one or more groups selected from Represents one or more groups selected from Further, in the formula, X represents a hydrogen atom or a chlorine atom, and the structural unit [(IV) +
(V)] and the structural unit (VI) are substantially equimolar. )