JPH06116373A - Copolymer polyester and polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject new copolymer for moldings, etc., containing an aromatic dicarboxylic acid component, a biphenol component and a glycol ester, having excellent heat resistance and high mechanical characteristics and exhibiting optical anisotropy in melting and capable of carrying out melt processing. CONSTITUTION:Terephthalic acid is mixed and reacted with 1,4- dihydroxybenzene, 4,4'-dihydroxybiphenyl, acetic anhydride and potassium acetate in a nitrogen stream at 140 deg.C for 1 hr and then at 250 deg.C for 1.5hr and made to react with polyethylene naphthalate at 270 deg.C for 2.5hr to provide the object copolymer. This copolymer contains a constitutional unit expressed by formula I (Ar1 is 2,6-naphthalene, 4.4'-biphenylene or phenylenes), formula II (Ar2 is phenylenes), formula III (Ar3 is a compound residue having 2 phenylene groups connected at para positions) or formula IV [R1 is 6-20 aromatic, 4-20C alicyclic or l-20C aliphatic hydrocarbon; R2 is 4-20C alicyclic or 1-20C aliphatic hydrocarbon; (n) is 2-300] and exhibits optical anisotropy in melting.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention can perform melt processing with a conventionally used apparatus, and can impart excellent heat resistance and high mechanical properties to the obtained molded product. The present invention relates to a copolyester having a novel optical anisotropy.

[0002]

2. Description of the Related Art Melt anisotropic polyesters using polyalkylene arylates such as polyethylene terephthalate, which are currently commercially available, are disclosed in Japanese Examined Patent Publication No. Sho 56-18016 and Japanese Unexamined Patent Publication No. Sho 60-186525. As disclosed in Japanese Unexamined Patent Publication (Kokai), etc., it is a polymer obtained by polymerizing p-acetoxybenzoic acid and polyethylene terephthalate while performing acid lysis. This polymer has a liquid crystal transition temperature of about 230 ° C and also has mechanical properties. It is excellent.
However, this polymer has, for example, a heat distortion temperature of
Since it has a low temperature of 65 to 70 ° C. and poor so-called thermal characteristics, it cannot be used for applications requiring heat resistance. The above-mentioned polymer is p-
There is also a defect that an insoluble insoluble material derived from acetoxybenzoic acid is formed.

[0003]

As a result of intensive research efforts to solve the above problems, the inventors of the present invention have achieved high heat resistance and excellent heat resistance without using p-acetoxybenzoic acid and a special copolymerization component. The present invention has been completed by finding a polyester having optical anisotropy with which a molded product having mechanical properties can be obtained. That is, the present invention, as an essential component,
Including the structural units represented by the following general formulas (I), (II), (III) and (IV), (I), (II) and (III) are added to the total of the structural units (I 50% by mole of the structural unit of () and 2% by the structural unit of (II)
~ 49 mol%, the constitutional unit of (III) is 1 to 48 mol%,
It is a copolyester showing optical anisotropy when melted, characterized in that the constituent unit of (IV) is 1 to 80 mol% with respect to all constituent units.

[0004]

[Chemical 2]

(Here, Ar ₁ is 2,6-naphthalene, 4, 4 '
-Biphenylene, 1,2-phenylene, 1,3-phenylene and 1,4-phenylene, and one or more groups selected from them, and Ar ₂ is selected from 1,3-phenylene and 1,4-phenylene. At least one group represented by the formula, Ar ₃ represents at least one group of a residue of a compound having a phenylene number of 2 or more connected in the para position, and R ₁ represents an aromatic hydrocarbon group having 6 to 20 carbon atoms or a carbon atom. An alicyclic hydrocarbon group having 4 to 20 carbon atoms or an aliphatic hydrocarbon group having 1 to 20 carbon atoms, and R ₂ represents an alicyclic hydrocarbon group having 4 to 20 carbon atoms or an aliphatic hydrocarbon group having 2 to 20 carbon atoms Base, n
Represents a number from 2 to 300. In order to embody the structural units (I) to (IV), various compounds having ordinary ester forming ability are used. The raw material compounds necessary for forming the copolyester constituting the present invention will be described in detail below step by step. The dicarboxylic acid component (I) is selected from 2,6-naphthalenedicarboxylic acid, 4,4'-biphenylenedicarboxylic acid, 1,2-phenylenedicarboxylic acid, 1,3-phenylenedicarboxylic acid and 1,4-phenylenedicarboxylic acid. It is preferably introduced from one or two or more kinds, particularly from 2,6-naphthalenedicarboxylic acid and 1,4-phenylenedicarboxylic acid. The amount of the structural unit (I) is 50 mol% based on all the structural units except (V) in the polymer.
Incidentally, since the above-mentioned dicarboxylic acid unit is introduced into the polymer, dicarboxylic acid or other diester-forming derivative can be used, but dicarboxylic acid is preferable.

On the other hand, the diol components are (II) and (III)
It consists of two types of structural units. Of these constitutional units, (I
I) is introduced from at least one diol selected from 1,3-phenylene diol and 1,4-phenylene diol, and particularly preferably introduced from 1,4-phenylene diol. The amount of the structural unit (II) is 2-49 mol%, preferably 10-49 mol%, based on all the structural units except (V) in the polymer. If the amount of the structural unit (II) deviates from this range, the melting point of the produced polymer remarkably rises and the molecular weight also decreases, which is not preferable.

The other diol structural unit (III) is a compound having a phenylene number of 2 or more, which is connected at the para position, for example,
It is introduced from at least one diol selected from polyphenylene diols such as 4,4'-biphenylene diol and 4,4 "-terphenylene diol, and particularly preferably introduced from 4,4'-biphenylene diol. The amount of the structural unit (III) is 1 to 48 mol%, preferably 10 to 40 mol% based on all structural units except (V) in the polymer.
Is. When the amount of the constituent unit (III) deviates from this range,
The melting point of the produced polymer remarkably rises and the molecular weight also decreases, which is not preferable.

In order to introduce the above diol units into the polymer, diols and other diester-forming derivatives such as diacetate, dipropionate and dibenzoate can be used. Next, the raw material polyester structural unit (IV) has a repeating structural unit represented by the above general formula, and the number n of the repeating units is 2 to 300, preferably 2 to 200.
A preferable raw material polyester is introduced from polyalkylene terephthalate or polyalkylene naphthalate.
These raw material polyesters can be manufactured by a general method well known in the art. The copolyester of the present invention is polymerized by a direct polymerization method or a transesterification method, and in the polymerization, a solvent polymerization method, a slurry polymerization method or the like is usually used.

In these polymerizations, various catalysts can be used, and typical ones are dialkyltin oxide, diaryltin oxide, titanium dioxide, alkoxytitanium silicates, titanium alcoholates, carboxylic acids. And alkali metal salts thereof, Lewis acid salts such as BF ₃ , and the like. The amount of catalyst used is generally preferably about 0.001 to 1% by weight, based on the total weight of the monomers. The polymer produced by these polymerization methods can be further increased in molecular weight by solid-state polymerization in which heating is performed under reduced pressure or in an inert gas. A liquid crystalline polymer that exhibits optical anisotropy when melted is an essential element in the present invention in order to have both thermal stability and easy processability. The property of melt anisotropy can be confirmed by a conventional polarization inspection method using a crossed polarizer. More specifically, the melt anisotropy was confirmed by using a polarizing microscope manufactured by Olympus, melting the sample placed on the hot stage manufactured by Rincom, and observing it under a nitrogen atmosphere at a magnification of 150 times. it can. The polymer is optically anisotropic and transmits light when inserted between crossed polarizers. When the sample is optically anisotropic, polarized light is transmitted even in the molten still liquid state, for example. Liquid crystallinity and melting point (liquid crystallinity manifesting temperature) are considered as indices of the processability of the present invention. Whether or not it exhibits liquid crystallinity is deeply related to the fluidity at the time of melting, and it is essential that the polyester of the present application exhibits liquid crystallinity in the molten state. A nematic liquid crystalline polymer causes a significant decrease in viscosity above its melting point, so that generally exhibiting liquid crystallinity at or above its melting point is an index of processability. The melting point (liquid crystallinity manifesting temperature) is preferably as high as possible from the viewpoint of heat resistance, but is 350 ° C or less in consideration of thermal deterioration during melt processing of the polymer and heating capacity of the molding machine. It is a good guide. Also, at least 10 ℃ to the melting point
It is preferable that the melt viscosity of the resin is 1 × 10 ⁶ poises or less under a shearing stress of 100 sec ⁻¹ at a temperature equal to or higher than the temperature at which is added. More preferably, it is 10 ⁴ poise or less. These melt viscosities are generally realized by having liquid crystallinity.

Next, the polyester of the present invention can be blended with various kinds of fibrous, powdery or plate-like inorganic and organic fillers depending on the purpose of use. As the fibrous filler, glass fiber, asbestos fiber, silica fiber, silica-alumina fiber, alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber, and further stainless steel, aluminum, titanium, copper Inorganic fibrous substances such as metallic fibrous substances such as brass. A particularly representative fibrous filler is glass fiber. In addition, high-melting-point organic fibrous substances such as polyamide, fluororesin, polyester resin, and acrylic resin can also be used.
On the other hand, as the granular filler, carbon black, graphite,
Silica, quartz powder, glass beads, milled glass fiber, glass balloon, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth,
Silicates such as wollastonite, iron oxide, titanium oxide,
Oxides of metals such as zinc oxide, antimony trioxide and alumina, carbonates of metals such as calcium carbonate and magnesium carbonate, sulfates of metals such as calcium sulfate and barium sulfate, other ferrites, silicon carbide, silicon nitride, boron nitride. , Various metal powders, and the like. Examples of the plate-like filler include mica, glass flakes, various metal foils and the like. Examples of organic fillers include heat-resistant and high-strength synthetic fibers such as aromatic polyester fibers, liquid crystal polymer fibers, aromatic polyamide, and polyimide fibers. These inorganic and organic fillers can be used alone or in combination of two or more. The combined use of the fibrous filler and the granular or plate-like filler is a preferable combination particularly in terms of having both mechanical strength, dimensional accuracy and electrical properties. The content of the inorganic filler is 95% by weight or less, preferably 1 to 80% by weight, based on the total amount of the composition. When using these fillers, it is desirable to use a sizing agent or a surface treatment agent if necessary.

Further, to the polyester of the present invention, other thermoplastic resin may be supplementarily added within a range not impairing the purpose intended by the present invention. Examples of thermoplastic resins used in this case include polyethylene, polypropylene and other polyolefins, polyethylene terephthalate, polybutylene terephthalate and other aromatic dicarboxylic acids and aromatic polyesters such as diols, polyacetals (homo or copolymers), polystyrene. , Polyvinyl chloride, polyamide, polycarbonate, ABS, polyphenylene oxide, polyphenylene sulfide, fluororesin and the like. Further, two or more kinds of these thermoplastic resins can be mixed and used.

[0012]

EFFECT OF THE INVENTION The copolymerized polyester and the composition thereof which show anisotropy when melted, which is composed of the specific constitutional unit obtained in the present invention, has good fluidity when melted and is excellent in thermal stability. Anisotropy can be expressed without using hydroxybenzoic acid or its ester-forming derivative, and injection molding, extrusion molding and compression molding are possible without using a molding machine having a special structure. Can be processed into three-dimensional molded products, fibers, films, etc. In addition, it has a good balance of thermal stability and is superior in heat resistance to the melt-anisotropic polyester using polyethylene terephthalate, which is commercially available, so that precision parts, especially connectors with narrow pitch intervals, It is suitable for thin-walled parts, wire coating materials, etc.

[0013]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. Example 1 As shown in Table 1, terephthalic acid 82.19 g (25 mol%), 1,
38.13 g of 4-dihydroxybenzene (17.5 mol%), 4,4 '
-Dihydroxybiphenyl 27.64 g (7.5 mol%), acetic anhydride 105.07 g, and 0.05 wt% potassium acetate with respect to the total amount charged were each charged into a reactor equipped with a stirrer, a nitrogen introducing pipe and a distilling pipe to carry out the reaction. After replacing the inside with nitrogen,
This mixture was reacted at 140 ° C. for 1 hour under a nitrogen stream. This was followed by heating to 250 ° C for 1.5 hours. At this time, about 60 g of acetic acid was distilled off. Next, after adding 119.84 g (50 mol%) of polyethylene naphthalate (PEN) to this reaction system, it was heated to 270 ° C. in 1.5 hours and further stirred at 270 ° C. for 1 hour. By this time, 90% or more of the theoretical amount of acetic acid was distilled. Next, the inside of the reactor was gradually depressurized at 270 ° C., further depressurized to 1 mmHg or less in 0.2 hours, and the reaction was carried out at this pressure for 3 hours. During this vacuum, a small amount of acetic acid distilled out. Further, after the completion of the reaction, nitrogen was introduced and the content was taken out. The obtained polymer was pale yellowish white, and the melting point measured by DSC manufactured by Perkin Elmer Co. was 215 ° C. Further, when the polymer was heated and observed under a crossed Nicol on a hot stage manufactured by Rincom under a polarizing microscope manufactured by Olympus, a nematic liquid crystal pattern was exhibited at a temperature higher than the melting point. Next, Yokohama Chemix's Mini Shot 2
A tensile test piece was prepared from this polymer using a mold machine, a tensile test piece was prepared from this polymer, and the result was measured using a tensile tester manufactured by Toyo Baldwin Co., Ltd., tensile strength 1530 kg / c.
It was m ² , and the tensile elongation was 2.5%. Next, the following values were used as the substitute characteristics in order to evaluate the strength retention under the melting point. That is, according to the Vicat method, the temperature at which a needle of a certain size begins to penetrate into a 0.5 mm thick pressed sheet under a constant load is defined as a high temperature holding temperature. The higher this value, the better the high temperature characteristics.

Examples 2 to 6 Polymerization was carried out in the same manner as in Example 1 at the composition ratios shown in Table 1, and the obtained polymers were evaluated in the same manner. Since the amount of heat transfer is small due to the composition ratio and the reliability of the data is lacking, the value measured by the melting point measuring device manufactured by Yanagi Headquarters is shown. The obtained polymer showed a liquid crystal pattern under the same conditions as in Example 1.

Comparative Examples 1 to 3 Polymerization was carried out in the same manner as in Example 1 with the composition ratios shown in Table 1. However, at 290 ° C, the viscosity increased remarkably, and finally when heated to 350 ° C, it solidified and could not be taken out from the reaction vessel.

Comparative Examples 4 to 5 Polymerization was carried out in the same manner as in Example 1 with the composition ratios shown in Table 1, and the obtained polymers were evaluated in the same manner as in Example 1.

Comparative Example 6 A polymer obtained on a laboratory scale was evaluated in the same manner as in Example 1 by the same procedure as in the industrial polymerization method which is usually used. Example 7 The polymer obtained in Example 1 was mixed with 30% by weight of glass fiber and extruded by an extruder manufactured by Haake Co., and a test piece was prepared and evaluated by the same method. Table 1 shows the above measurement results.

[0018]

[Table 1]

(Note to Table 1) * NDA; 2,6-naphthalenedicarboxylic acid TPA; terephthalic acid HQ; 1,4-dihydroxybenzene (1,4-phenylenediol) BP; 4,4'-dihydroxybiphenyl HBA; P-Hydroxybenzoic acid PET; Polyethylene terephthalate PEN; Polyethylene naphthalate N / A; Solidified and cannot be removed from the reaction vessel

Claims (2)

[Claims] 1. The following general formula (I):
(II), (III), including a structural unit represented by (IV), the above (I)
And (II) and (III) in total, the structural unit of (I) is 50 mol%, the structural unit of (II) is 2 to 49 mol%, (I
A copolymer having optical anisotropy when melted, characterized in that the constitutional unit of (II) is 1 to 48 mol% and the constitutional unit of (IV) is 1 to 80 mol% with respect to all the constitutional units. polyester. [Chemical 1] (Here, Ar ₁ represents one or more groups selected from 2,6-naphthalene, 4,4′-biphenylene, 1,2-phenylene, 1,3-phenylene and 1,4-phenylene. , Ar ₂ represents at least one group selected from 1,3-phenylene and 1,4-phenylene, and Ar ₃ represents at least one group of a residue of a compound having a phenylene number of 2 or more and linked at the para position. , R ₁ is an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alicyclic hydrocarbon group having 4 to 20 carbon atoms, or 1 to 20 carbon atoms
R ₂ is an alicyclic hydrocarbon group having 4 to 20 carbon atoms or an aliphatic hydrocarbon group having 2 to 20 carbon atoms, and n is 2 to 30.
Represents the number 0. ) 2. A polyester resin composition obtained by blending the copolymerized polyester according to claim 1 with an inorganic filler in an amount of 95% by weight or less (based on the total amount of the composition).