JPS62265341A - Polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain a polyester resin composition having excellent moldability, good heat resistance and high flame retardancy, by mixing a specified thermotropic liquid crystal random copolyester with another thermoplastic resin. CONSTITUTION:This resin composition contains a thermotropic liquid crystal random copolyester (a) of an intrinsic viscosity >=0.5, wherein units of formula I amount to 5-95mol% based on the units constituting the main chain and units of formula II amount to 95-5mol%, wherein Ar<1> is a trivalent aromatic group, Ar<2> is a bivalent aromatic group, provided that these aromatic rings may have substituents) and another thermotropic resin (b). As said another thermoplastic resin (b), polyethylene terephthalate, polybutylene terephthalate or polycarbonate is desirable. The mixing ratio of said composition is preferably such that component (a) amounts to 20-80wt%.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention comprises one thermotropic liquid crystalline phosphorus-containing polyester and another thermoplastic resin. This invention relates to a polyester resin composition that has excellent heat resistance, flame retardancy, and moldability.

(Prior Art) Fully aromatic polyester (bolyarylate) has been known as a heat-resistant polymer. In general, although fully aromatic polyesters have excellent physical properties, they have extremely high melting points (and at the same time high melt viscosity), which is extremely inconvenient as they must be processed at high temperatures and pressures. Moreover, prolonged exposure to high temperatures is not a good idea from the viewpoint of polyester decomposition, and is also economically disadvantageous.

Thermotropic liquid crystalline polyesters with excellent processability have recently attracted attention and are being actively researched.

However, conventionally proposed thermotropic liquid crystalline polyesters lacked sufficient melt processability, heat resistance, and flame retardancy.

On the other hand, thermoplastic resins such as polyethylene terephthalate, polybutylene terephthalate, and polycarbonate are widely used as engineering plastics with good moldability. A problem has arisen in that flammability is insufficient.

In addition, attempts have been made to blend other polymers with the aim of improving the moldability and mechanical properties of thermotropic liquid crystalline polyester2. Lj: It has been proposed to blend polyalkylene terephthalate, polycarbonate, etc. (Japanese Unexamined Patent Publication No. 57-2
5234, No. 57-44551). However, although such compositions improve moldability and mechanical properties to some extent, they are not sufficient and flame retardance is not improved at all.

(Problems to be Solved by the Invention) The present invention solves the drawbacks of conventional thermotropic liquid crystalline polyester and thermoplastic resins as engineering plastics, and has excellent moldability, good heat resistance, and high resistance to heat resistance. The object of the present invention is to provide a polyester resin composition that also has flame retardancy.

(Means for Solving the Problems) In order to achieve the above object, the present inventors have conducted extensive research and found that a combination of a phosphor-containing polyester having a specific structure of thermodropink liquid crystallinity and other thermoplastic resins has been developed. They found that it is effective to form a composition and have arrived at the present invention.

That is, the gist of the present invention is as follows.

5 to 95 mol% of the units constituting the main chain have the following structural formula (I
), and 95 to 5 mol% is a unit represented by the following structural formula (II). A polyester resin composition comprising a thermotropic liquid crystalline random copolyester having an intrinsic viscosity of 0.5 or more and another thermoplastic resin.

-0-Ar2-Co -(II) (Ar' represents a trivalent aromatic group, and Ar2 represents a divalent aromatic group. However, the aromatic ring may have a substituent.) This invention The copolyester in is a thermotropic liquid crystalline random copolyester containing 5 to 95 mol%, preferably 10 to 80 mol%, more preferably 20 to 40 mol% of units represented by structural formula (1), and has good properties. It has good melt moldability, and has a normal melting point of 350°C or less.
Preferably, the temperature is 300°C or less. If there are too many units represented by structural formula (1), the strength of the molded product will decrease, while if there are too few, the melting point will become too high or the flame retardance will decrease.

Ar' in structural formula (1) is most preferably a Hensen ring or a naphthalene ring. Further, in Structural Formula (1), the hydrogen atom of the aromatic ring may be substituted with an alkyl group having 1 to 20 carbon atoms, an aryl group, an alkoxy group, an allyloxy group, or a halogen atom.

The unit of structural formula (I) is derived from a phosphorus-containing aromatic diol component and an aromatic dicarboxylic acid component.

A specific example of the phosphorus-containing aromatic diol is the following formula (al
- (d) are mentioned, and particularly preferred are those represented by formula 1 (a) and formula (bl).

As aromatic dicarboxylic acid, terephthalic acid (TPA)
and isophthalic acid (IPA) are preferred, and the molar ratio of TPA and IPA is 100:O to O: 100. Preferably 100:'0 to 50:50. Optimally 10
It is appropriate to use them in a ratio of 0:0 to 80:20.

The second unit forming the copolyester together with the unit of structural formula (1) is a unit consisting of an oxycarboxylic acid residue represented by structural formula (If).

Ar" in structural formula (II) is most preferably a benzene ring or a naphthalene ring. In addition, in structural formula (n), the hydrogen atom of the aromatic ring is an alkyl group having 1 to 20 carbon atoms, an aryl group, an alkoxy group, It may be substituted with an allyloxy group or a halogen atom.

Specific examples of these include 4-hydroxybenzoic acid residues and 6-hydroxy-2-naphthoic acid residues, but the most preferred is 4-hydroxybenzoic acid residues.

In addition, components other than the above may be copolymerized within the range of forming a thermodropink liquid crystalline copolyester with good melt moldability (such copolymerized components include 1.4-
naphthohydroquinone, 2.6-naphthohydroquinone, 4.4'-dihydroxydiphenyl, naphthalic acid,
Examples include 2,2-bis(4-carboxyphenyl)propane, bis(4-carboxyphenyl)methane, bis(4-carboxyphenyl)ether 1 ethylene glycol, cyclohexane dimetatool, and pentaerythritol.

As an example of a preferred copolyester in the present invention,
9,10-dihydro-9-oxa-10-(2') in which the unit represented by structural formula (I) is represented by the above formula (a).

A unit derived from 5'-dihydroxyphenyl)phosphaphenanthrene-10-oxide (PIIQ) and TPA/IPA, a unit represented by structural formula (II) consisting of a 4-hydroxybenzoic acid (4HBA) residue An example of a manufacturing method for the copolyester unit will be explained.

(a) An acid component consisting of TPA/IPA, a diol component consisting of a diacetate form of PIIQ (Pllo-A), and an oxycarboxylic acid component consisting of an acetate form of 411BA (411BA-A) are combined with a hydroxyl group and a carboxyl group. equivalent amount (and preferably at the same time 0.01 to 0.25 times equivalent of acetic anhydride to the amount of total hydroxyl groups)
Or (b) TPA/acid component consisting of TPA and PH
The diol component consisting of Q and the oxycarboxylic acid component consisting of 411BA are combined with hydroxyl groups and carboxyl groups in an amount of 1.05 to 1.05 of the total amount of hydroxyl groups.
1.25 times the amount of acetic anhydride was charged into a reactor, and under normal pressure,
Esterification reaction or acid exchange reaction is carried out at a temperature of about 150° C. for about 2 hours. Thereafter, the temperature is raised sequentially, and if necessary, acetic acid is distilled out while reducing the pressure, and an acid exchange reaction is carried out.

Then, finally, usually at a temperature of 250 to 350"C,
A copolyester having melt moldability can be obtained by carrying out a polycondensation reaction in the melt phase or solid phase under a high vacuum of less than 1 Torr for several tens of minutes to several hours.

Although a catalyst is usually used in the 9-polymer condensation reaction, one or more compounds selected from various metal compounds and organic sulfonic acid compounds are used in the production of the copolyester in the present invention.

Such metal compounds include antimony, titanium, germanium, tin, zinc, and aluminum.

Magnesium, Calcilla 1% 1 Compounds such as manganese, sodium or cobalt are used, while.

Examples of organic sulfonic acid compounds include sulfosalicylic acid, 0
-Compounds such as sulfobenzoic anhydride are used. Particularly preferred are dimethyltin maleate and 0-sulfobenzoic anhydride.

The amount of catalyst added is usually 0.00% per mole of polyester structural unit. 'X 10-' to 100 X 10-' mol, preferably 0.5 X 10-' to 50 X 10-' mol,
Optimally, 1 x 10-4 to 10 x 10-' moles are suitable.

Note that during the single polycondensation reaction, depending on the type of constituent units of the polyester, it may solidify into a solid state, or it may be able to undergo polycondensation while remaining in a molten state.

The copolyester in the present invention has an intrinsic viscosity [η] of 0.
．． It needs to be 5 or more, preferably 1.0 to
10.0. The optimum value is 3.0 to 6.0.

If [η] is smaller than this range, various physical and mechanical property values including heat resistance will be inferior.

When [η] is larger than this range, the melt viscosity becomes too high, which impairs fluidity, or the melting point becomes too high, making it necessary to raise the molding temperature significantly, which is not preferable.

9 The thermal properties of the copolyester in the present invention include a melting point of 350°C or lower, a heat distortion temperature of 155°C or higher, preferably a melting point of 330°C or lower, and a heat distortion temperature of 180°C or higher.
Optimally, the melting point is 280-300℃, and the heat distortion temperature is 180-2.
A temperature of 30° C. is appropriate in terms of achieving both heat resistance and various physical and Ja mechanical property values.

Next, the thermoplastic resin to be added to the thermotropic liquid crystalline copolyester may be one that improves the moldability of the thermotropic liquid crystalline copolyester;
It may be either amorphous or thermotropic liquid crystal, but usually one without thermotropic liquid crystal is used.

Specific examples of such thermoplastic resins include polyarylates from bisphenol compounds and TPA/IPA dicarboxylic acid compounds, polyarylates from BA-based oxycarboxylic acid compounds, polyalkylene terephthalate polycarbonates such as polyethylene terephthalate, and polybutylene terephthalate. , polyetheretherketone, polysulfone, polyethersulfone, etc., and two or more of these may be used in combination.

The most preferred thermoplastic resins are polyalkylene terephthalates selected from polyethylene terephthalate and polybutylene terephthalate (including copolymers based thereon) and polycarbonates. As the polycarbonate, 4,4'-dioxydiallylalkane polycarbonate is particularly suitable.2For example, bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxy) phenyl)
Propane, bis(4-hydroxy-3,5-dichlorophenyl)methane, 2,2-bis(4-hydroxy-3,
Polycarbonates obtained from 4,4'-dioxydiphenyl alkanes such as 5-dimethylphenyl)propane and bis(4-hydroxyphenyl)phenylmethane and phosgene or diphenyl carbonate are preferably used.

The proportion of the thermotropic liquid crystalline copolyester and the thermoplastic resin is preferably such that the former accounts for 8 to 80% by weight of the composition, preferably 20 to 80% by weight, optimally 50 to 80% by weight. . If the amount of copolyester is too large, the strength of the molded product will decrease, whereas if the amount is too small, the glass transition temperature will become low or the flammability will be insufficient, which is not preferable.

To obtain a composition by mixing the thermotropic liquid crystalline copolyester and other thermoplastic resin, the surrounding components are mixed by a solution blending method or a mixing method using a two-roll, Banbury mixer-1 melt extruder or other mixer. Just mix it evenly.

(Example) Next, the present invention will be explained in more detail with reference to Examples.

[η] was determined from the solution viscosity measured at 20°C using a mixed solvent of equal weights of phenol and tetrachloroethane.

The melting point was measured using a PerkinElmer DSC-2 differential scanning calorimeter, and the heat distortion temperature was determined according to JIS K7207.
Measured under heavy load in accordance with .

The Izots narrowing strength is according to ASTM D256 standard.

The thickness was measured at 1/8 inch.

Flame retardancy is determined by the ``flammability class'' (IL) according to the UL-94 standard.
B, V-2゜V-1, V-0) and JIS K 7
The determination was made using the limiting oxygen index (LOI) according to the 201 standard.

In addition, the thermotropic liquid crystal is equipped with a photostage L.
Confirmed using an Eitz polarization microscope.

Furthermore, the formability was evaluated by forming a 100φ x 1/8 inch disk-shaped test piece using a J-100-5 type forming machine manufactured by Japan Steel Works, and evaluating it according to the following criteria according to the conditions at that time. .

◎: Injection time is 10 seconds or less and molding temperature is 330℃
Below ○: Injection time is 10 to 15 seconds and molding temperature is 330
Less than °C △: Injection time is 15-30 seconds and molding temperature is 330
Less than ℃: Injection time is 30 seconds or more or molding temperature is 330℃ or more. P) Prepare TP8 in the same mole as IQ-8, and use dimethyltin maleate as a catalyst at 4X10 per mole of polyester structural unit.
−'Mole added.

The reaction was carried out under a nitrogen atmosphere at normal pressure and 150° C. for 2 hours with mixing. The reaction mixture was heated at 250°C for 2 hours under normal pressure.

Further, the reaction was carried out at 260° C. for 2 hours at 50 torr. Next, this reaction product was heated one after another under a reduced pressure of 0.1 torr to carry out the ζ reaction, and finally the temperature was raised to 320°C and melt polymerization was carried out for a total of 9 hours for 3 hours.

The obtained copolyester was a liquid crystalline copolyester with [η) of 5.41 and a good color tone.

This copolyester and polyethylene terephthalate resin (PET), polybutylene terephthalate resin (PB
T) or polycarbonate resin (PC”) as the first
After mixing thoroughly in the proportions shown in the table, use a complete screw extruder equipped with a die with a diameter of 4 mm at the tip (screw diameter 3 mm).
wm, L/D20), screw rotation speed 3
It was extruded into a strand at Qrpm at a processing temperature corresponding to the composition, and after cooling, it was cut into 3 squares in length to obtain 1 granule.

Using this granule, 1/8 x 1/8 x 5
(inch) sample pieces were molded and the physical properties were determined to be 211.11. The results are shown in Table 1.

As Comparative Examples 1 to 4, the results of molding each of the above resins individually are listed in Table 1.

Example 10 PIIQ, resorcinol (R5), and 1HBA in the reactor
and acetic anhydride in a molar ratio of 6:1:3:15 and pH and R.
5, and dimethyltin maleate was added as a catalyst in an amount of 4 x 10-' mol per 1 mol of polyester, under nitrogen atmosphere, at normal pressure, 15
The reaction was allowed to proceed at 0°C for 2 hours with mixing. The reaction was heated under reduced pressure to 250° C. for 2 hours and then to 50 torr.

The reaction was carried out at 260°C for 2 hours. This reactant is then reduced to 0
．． The reaction was carried out under a reduced pressure of 1 Torr while the temperature was raised sequentially, and the temperature was finally raised to 310°C for volumetric polymerization for a total of 5 hours).

The obtained copolyester was a liquid crystalline copolyester with [η) of 2.99 and a good color tone.

This copolyester and PUT were mixed at a weight ratio of 80/20, molded in the same manner as in Example 1, and the physical properties were evaluated. The results are shown in Table 2.

Example 11 PIIQ, hydroquinone (IQ) and 411 in a reactor
BA and acetic anhydride in a molar ratio of 5:1:3:18 and PII
The sum of Q and liQ and equimolar TPA/IPA (molar ratio 60
/40).

As a catalyst, 4×10 −' mol of dimethyltin maleate was added per 1 mol of the polyester structural unit, and the mixture was reacted with mixing at 150° C. for 2 hours under a nitrogen atmosphere at normal pressure.

This reaction product was heated at 250°C for 2 hours under normal pressure.

Further, the reaction was carried out at 260° C. for 2 hours at 50 torr. Next, this reactant was heated under a reduced pressure of 0.1 Torr to carry out the reaction, and finally the temperature was raised to 320°C and 1
Melt polymerization was carried out for a total of 4 hours.

The obtained copolyester was a liquid crystalline copolyester with [η) of 1.25 and a good color tone.

The weight ratio of this copolyester and PET is 80/20.
Table 2 shows the results of mixing and molding in the same manner as in Example 1 and evaluating the physical properties.

Examples 12 to 18 PHQ-8, 4HB8-A, with the molar ratio shown in Table 2
IIQ-8 (H diacetate) and TPA /
A copolyester was obtained in the same manner as in Example 1 using IPA.

The weight ratio of these copolyesters and PET is 80/20.
Table 2 shows the results of mixing and molding in the same manner as in Example 1 and evaluating the physical properties.

As Comparative Examples 5 to 7, examples in which experiments were conducted in the same manner as in Example 1 using copolyesters that do not exhibit thermotropic liquid crystallinity are appended. (In Comparative Example 5, the copolyester could not be mixed uniformly with PET, and in Comparative Examples 6 and 7, the melting point and melt viscosity of the copolyester were too high to be molded using a general-purpose molding machine.

Examples 19 to 21 Table 2 shows the physical properties of test pieces obtained in the same manner as in Example 1, except that another phosphorus compound was used instead of PHQ-A in Example 1.

Note that in Table 1, the numbers in front of the numbers in the PIIQ column of Examples 19 to 21, c, and d represent the above structural formula (
b), (cl, (di) indicates the use of a diacetate of an organic phosphorus compound.

(Effects of the Invention) According to the present invention, the high heat resistance and flame retardancy of the phosphorus-containing thermotropic liquid crystalline copolyester and the excellent moldability of the thermoplastic resin are wicked in a well-balanced manner, making them useful as engineering plastics. Provided is a polyester resin composition that has excellent heat resistance, flame retardancy, and good moldability.

Claims (5)

[Claims] (1) 5 to 95 mol% of the units constituting the main chain are units represented by the following structural formula (I), and 95 to 5 mol% are units represented by the following structural formula (II), Intrinsic viscosity is 0.
A polyester resin composition comprising a thermotropic liquid crystalline random copolyester of 5 or more and another thermoplastic resin. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) [Ar^1 indicates a trivalent aromatic group, Ar^2 indicates a divalent aromatic group . However, the aromatic ring may have a substituent. ] (2) The polyester resin composition according to claim 1, wherein the unit represented by structural formula (I) is represented by the following structural formula. ▲Contains mathematical formulas, chemical formulas, tables, etc.▼ (3) The polyester resin composition according to claim 1, wherein the unit represented by structural formula (I) is represented by the following structural formula. ▲Contains mathematical formulas, chemical formulas, tables, etc.▼ (4) The polyester resin composition according to claim 1, 2, or 3, wherein the unit represented by structural formula (II) is a 4-hydroxybenzoic acid residue. (5) The polyester resin composition according to claim 1, 2, 3, or 4, wherein the thermoplastic resin is polyethylene terephthalate, polybutylene terephthalate, or polycarbonate.