JPS63277233A - Aromatic copolyester - Google Patents

Abstract

PURPOSE:To obtain the titled copolyester, having excellent heat resistance, flame retardance and melt moldability and suitable as films, fibers, etc., by reacting a phosphorus-containing aromatic diol with aromatic dicarboxylic acid and hydroxycarboxylic acid in a specific proportion. CONSTITUTION:The aimed copolyester, obtained by polycondensing (A) a phosphorus-containing aromatic diol prepared by reacting a phosphinic acid with a quinone and capable of providing structural units expressed by formula I (Ar<1> is aromatic group; R<1> and R<2> are 3-4C alkylene) with (B) an aromatic dicarboxylic acid (e.g. terephthalic acid) capable of providing structural units expressed by formula II (Ar<2> is aromatic group) in an amount equimolar with the component (A) and (C) an aromatic hydroxycarboxylic acid (e.g. 4- hydroxybenzoic acid) capable of providing structural units expressed by formula III (Ar<3> is aromatic group) at 95/5-5/95 molar ratio thereof to the component (A) and having >=0.5 intrinsic viscosity.

Description

[Detailed description of the invention] (Industrial application field) The present invention mainly focuses on phosphorus-containing aromatic diol components.

The present invention relates to an aromatic copolyester with excellent heat resistance and flame retardancy obtained from an aromatic dicarboxylic acid component and an aromatic hydroxycarboxylic acid component.

(Prior Art) Aromatic polyesters have been well known as heat-resistant polymers. However, most aromatic polyesters are difficult to mold materials and have limited applications.

In addition, aromatic polyester is generally said to have excellent flame retardancy, but the limiting oxygen index described below is at most 4.
It is about 0, and it is difficult to say that it has sufficient flame retardancy.

The present inventors previously proposed a polyester consisting of a structural unit represented by the linear formula as an aromatic polyester having excellent heat resistance and flame retardance (Japanese Patent Application Laid-open No. 240722/1983).

This polyester has excellent heat resistance and flame retardancy, and has 6 color tones (1)
Although the transparency is good, there are problems in that the melting point or flow start temperature is high, the moldability is insufficient, and the diol component is extremely expensive, resulting in high costs. In addition, when this polyester is used as it is for molding, it gives a molded product with sufficient flame retardancy, but when used as a flame retardant, the content of phosphorus atoms is too small to be satisfactory.

(Problems to be solved by the invention) As described above, it has been extremely difficult to obtain a general-purpose polyester that is satisfactory in all aspects of heat resistance, flame retardance, melt moldability, and economic efficiency. .

The present invention seeks to provide a heat-resistant aromatic polyester that can be produced at relatively low cost, has good melt moldability, has a high degree of flame retardancy, and is suitable for use at high temperatures. .

(Means for Solving the Problems) In order to achieve the above object, the present inventors conducted intensive research and found that a phosphorus-containing aromatic copolyester having a specific structure has extremely excellent properties. 1. The present invention has been achieved.

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

It mainly consists of structural units represented by the following structural formulas (■ to ■), and the ratio of each constituent m position is such that [1] and [2] are substantially equimolar, and [1] and [3] are 9515 to 9515. A random copolyester having a molar ratio of 5/95 and an aromatic copolyester having an intrinsic viscosity of 0.5 or more.

80 Tomi P-0 -O-Ar' -0-■ R'-QC-Ar''-Co-■ -QC-Ar3-0- ■ (In the formula, Ar' is a tetravalent aromatic group, Ar' and Ar
' is a divalent aromatic group; R1 and R'' represent an alkylene group having 3 or 4 carbon atoms forming a ring;

However, the aromatic ring and the alkylene group may have a substituent. ) The copolyester of the present invention is synthesized mainly from a phosphorus-containing aromatic diol or its ester-forming attractant, an aromatic dicarboxylic acid or its ester-forming derivative, and an aromatic hydroxycarboxylic acid or its ester-forming derivative.

The phosphorus-containing aromatic diol in the present invention is represented by the following formula (1):
It is indicated by.

o=p-.

HO-Ar'-OH (1) Ar' is preferably a benzene ring or a naphthalene ring, and the hydrogen atom of the aromatic ring is a lower alkyl group.

It may be substituted with a lower alkoxy group or a halogen atom.

Moreover, R1 and R2 are trimethylene groups.

A tetramethylene group and a portion of its hydrogen atoms substituted with a lower alkyl group, a lower alkoxy group, a halogen atom, etc. are suitable.

A specific example of the phosphorus-containing aromatic diol is the following formula (a):
-(The compound represented by 81 is mentioned.

'I CH3-CHCH2 fc) (dl(
e) CH: I-CHCHz l \ CHt CHt CHz-CHz These phosphorus-containing aromatic diols can be produced by reacting the corresponding phosphinic acid and quinone in a solvent such as ethyl cellosolve or xylene. can(
(Patent Application No. 1983-274310).

Further, the aromatic dicarboxylic acid is represented by the following formula (2).

HOOC-Ar"-COOH (21 Ar" is preferably a benzene ring or a naphthalene ring, and may have the same substituent as Ar'.

A specific example of an aromatic dicarboxylic acid is terephthalic acid (
TPA), isophthalic acid (IPΔ), 1,4-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid.

4.4'-diphenyldicarboxylic acid, 2.2-bis(4
'-Carboxyphenyl)propane, bis(4-carboxyphenyl)methane, and bis(4-carboxyphenyl)ether.

Particularly preferred aromatic dicarboxylic acids are TPA and IP
A, the molar ratio of TPA and IP8 is 10010~
O/100° preferably 10010-50150. Optimally, it is best to use a ratio of 10010 to 70/30.

Further, the aromatic hydroxycarboxylic acid has the following formula % Formula % Ar'' is preferably a benzene ring or a naphthalene ring, and may have the same substituent as Ar'.

Specific examples of the aromatic hydroxycarboxylic acid include 4-hydroxybenzoic acid and 2-hydroxy-6-naphthoic acid, with 4-hydroxybenzoic acid being particularly preferred.

In the copolyester of the present invention, the ratio of the structural units (1) and (2) needs to be substantially equimolar; unless this condition is met, a copolyester with a high degree of polymerization cannot be obtained.

In addition, the ratio of constituent units ■ and ■ is 9515 to 5/95
It is necessary to have a molar ratio of 80/2, preferably 80/2.
A molar ratio of 0 to 10/90 is suitable. In particular, in order to obtain a thermotropic liquid crystalline copolyester, 501
A molar ratio of 50 to 10/90 is suitable. If the proportion of the structural unit (■) becomes too large, the strength and heat resistance will decrease, and if the proportion of the structural unit (■) becomes too large, the melting point or flow start temperature may become too high.

Flame retardancy may decrease.

Furthermore, components other than those mentioned above may be copolymerized within a range that does not impair the properties of the copolyester of the present invention. Examples of such copolymerized components include resorcinol, hydroquinone, 4,4'-dihydroxydiphenyl, Ethylene glycol, diethylene glycol, 1,4-butanediol, 1,6-hexanediol, 2-butene-1,4
-diol, cyclohexane dimetatool, trimellitic acid, etc.

The polyester of the present invention has an intrinsic viscosity [η] of 0.
It needs to be 5 or more, preferably 1. θ〜1
0.0. The optimum value is 1.0 to 3.0. If [η] is less than 0.5, various physical and chemical properties including heat resistance will be poor, which is not preferable. However, if [η] is too large, the melt viscosity may become too high and melt moldability may be impaired, which is undesirable.

The copolyester of the present invention can be produced by conventional methods for producing aromatic polyesters.

For example, ■ substantially equimolar amounts of phosphorus-containing aromatic diol, aromatic dicarboxylic acid, and hydroxyl groups or more;
Preferably 1.05 to 1.25 equivalents of lower fatty acid anhydride 1, such as acetic anhydride, or ◎Substantially equimolar lower fatty acid ester of phosphorus-containing aromatic diol and aromatic dicarboxylic acid (preferably hydroxyl residue). 0.0 of the amount of groups
5 to 0.25 equivalents of lower fatty acid anhydrides) were charged into the reactor.

Obtained by polycondensation reaction.

1 usually for producing the copolyesters of the present invention.

A polycondensation catalyst is used, and the double condensation catalyst is one selected from various metal compounds and organic sulfonic acid compounds.
More than one type of compound can be used.

As the metal compound, compounds such as antimony, titanium, germanium, tin, zinc, aluminum, magnesium, calcium, manganese, potassium, sodium, or cobalt are used.

Examples of organic sulfonic acid compounds include sulfosalicylic acid, 0
Compounds such as -sulfobenzoic anhydride are used, and dimethyltin malenyi I and 0-sulfobenzoic anhydride are particularly preferably used.

The amount of the catalyst added is usually 0.1X10-' to 100X10-' mole, preferably 0.5X10-' to 50X10-' mole, optimally 1x10-' to 1x10-' mole, per mole of the polyester structural unit. 10XIO-' moles are suitable.

The polycondensation reaction is first carried out at a temperature of about 150°C under normal pressure.
After carrying out the acid exchange reaction or esterification reaction for about 2 hours, the temperature is sequentially raised to about 270°C, and if necessary, the pressure is reduced to distill acetic acid while the reaction is carried out.
The reaction is carried out at a temperature of 1 Torr or less under reduced pressure for several tens of minutes to several hours.

Note that in some cases, it solidifies during the nine-polycondensation reaction and becomes a solid state, and in other cases, it can be polycondensed while remaining in a molten state.
□ (Example) Next, the present invention will be described in more detail with reference to Examples.

In addition, the method of measuring the characteristic value is as follows.

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

The temperature was measured using a glass-Xsho (T) and TII+ differential scanning calorimeter (Model DSC-2, manufactured by PerkinElmer) at a heating rate of 20° C./min.

'+ * ff'++a (Tf) Using a flow tester (CFT 500 type manufactured by Shimadzu Corporation), a load of 100 kg/cr1. The temperature was raised from 200°C at a rate of 10°C/min under the condition that the nozzle diameter was 0.5°.

It was determined as the temperature at which the polymer begins to flow out.

Limiting Oxygen Index (LOI) according to JIS K7201 standard
was determined for a sample with a PJ size of 1 x 16 inches.

Example 1 A phosphorus-containing aromatic diol of the formula (al), TPA, 4-hydroxybenzoic acid, and acetic anhydride were charged in a polycondensation reactor at a molar ratio of 30:30:70:150, and dimethyltin male was used as a catalyst. Add 4 x 10-' moles of ate per mole of repeating units of the polyester.

Under nitrogen atmosphere, normal pressure, 2 hours at 150℃, 2 hours at 280℃
The reaction was allowed to take place while mixing for a period of time.

After that, the temperature was gradually increased and the pressure was reduced until the temperature reached 320'C.

The polycondensation reaction was carried out for 2 hours under reduced pressure of 1 torr or less.

The obtained copolyester has [η) 1.31. T
It was a thermotropic liquid crystalline copolyester with a good color tone of f263°C and LOI 71.゛The infrared absorption spectrum of this copolyester is shown in Figure 1.

Examples 2 to 5 Copolyesters were produced in substantially the same manner as in Example 1, except that the compounds of the formulas (bl to (e)) were used as the phosphorus-containing aromatic diol.

Table 1 shows the characteristic values of the obtained copolyester.

Example 6 In a polycondensation reactor, diacetate of phosphorus-containing aromatic diol (PenAQ-A) of the formula (al), TP^, acetate-1-(411BA-A) of 4-hydroxybenzoic acid, and acetic anhydride were added. (AczO) was prepared at a molar ratio of 30:30 near 0 near.

A copolyester was produced in the same manner as in Example 1 except for the above.

The obtained copolyester has [η) 1.98. T
It was a thermotrobi-tsuku liquid crystalline copolyester with a good color tone of f264°C and LOI 71.

The infrared absorption spectrum of this copolyester is shown in FIG.

Examples 7 to 9 Except for changing the charging raw materials to the charging molar ratio shown in Table 2,
A copolyester was produced in the same manner as in Example 6.

Table 2 shows the characteristic values of the obtained copolyester.

Example 10 P-8Q-A, TPA, IPA, 4HBA
A copolyester was produced in the same manner as in Example 6, except that -8 and Ae, 0 were charged in a molar ratio of 90:30:60:10.

The obtained copolyester has [η) 1.05. '
The amorphous copolyester had a rg of 178°C and an LOI of 70, with good color tone and transparency.

Example 11 PWAQ-8, TPA, 4H13A-8 and Ac, 0
A copolyester was produced in the same manner as in Example 6 except that s:s:9s:'y molar ratio was used.

The obtained copolyester has [η) 1.87. T
It was a crystalline copolyester with good color tone at n+398°C and LOI 67.

Comparative Example A copolyester was prepared in the same manner as in Example 6, except that TPA, IPA, 4HBA-A, and Ac, 0 were charged to PWA Rohachi in a molar ratio of 1:0.9:0.1:99:6. Manufactured.

The obtained copolyester has a [η) of 2.45. L.O.
I73, it began to decompose at 450° C. and had virtually no observed melting point, making it difficult to melt and mold and could not be put to practical use.

(Effects of the Invention) According to the present invention, the melting point or flow start temperature is relatively low;
A novel aromatic copolyester that has excellent properties as a heat-resistant, flame-retardant polymer and can be produced economically is provided. It is useful for films, fibers, molding materials, plasma spray coatings, and as a modifier for flame retardants.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the infrared absorption spectrum of the copolyester obtained in Example 1, and FIG. 2 is a diagram showing the infrared absorption spectrum of the copolyester obtained in Example 6.

Claims (2)

[Claims] (1) Mainly composed of structural units represented by the following structural formulas [1] to [3], and the ratio of each structural unit is [1] and [2].
are substantially equimolar, and [1] and [3] are 95/5~
A random copolyester having a molar ratio of 5/95 and an aromatic copolyester having an intrinsic viscosity of 0.5 or more. ▲There are mathematical formulas, chemical formulas, tables, etc.▼[1] -OC-Ar^2-CO-[2] -OC-Ar^3-O-[3] (In the formula, Ar^1 is a tetravalent aromatic The groups Ar^2 and Ar^3 are divalent aromatic groups, and R^1 and R^2 are alkylene groups having 3 or 4 carbon atoms forming a ring. However, aromatic rings and alkylene groups (It may have a substituent.) (2) The copolyester according to claim 1, wherein the copolyester has a composition exhibiting thermotropic liquid crystallinity.