JPS63199226A - Production of aromatic copolyester - Google Patents

Abstract

PURPOSE:To obtain the titled polymer having excellent heat resistance, by adding and reacting and acid anhydride of a lower fatty acid with an aromatic diol containing phosphorus atom and an aromatic dicarboxylic acid and then reacting an aromatic hydroxycarboxylic acid therewith. CONSTITUTION:(A) An aromatic diol, containing phosphorus atom and expressed by formula I (Ar<1> is trifunctional aromatic group; R<1> and R<2> are H or lower acyl) and (B) an aromatic dicarboxylic acid expressed by formula II (Ar<2> is bifunctional aromatic group) (e.g. terephthalic acid, etc.) and (C) an acid anhydride of a lower fatty acid (e.g. acetic anhydride, etc.) are reacted by, e.g. mixing the components (A) with (B) in equimolar amounts at 130-200 deg.C, and (D) an aromatic hydroxycarboxylic acid expressed by formula III (Ar<3> is trifunctional aromatic group; R<3> is H or lower acyl) (e.g. 4-hydroxybenzoic acid, etc.) at 30/70-50/50 molar ratio based on the component (A) is added to carry out polycondensation at 150-200 deg.C and afford the aimed polyester.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides an aromatic diol component mainly containing a phosphorus atom, an aromatic dicarboxylic acid component, and an aromatic oxycarboxylic acid component, which have excellent heat resistance and little foreign matter. The present invention relates to a method for economically producing aromatic copolyesters.

(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.

-JC, heat-resistant aromatic polyester has a very high melting point and high melt viscosity, so it is extremely inconvenient that it must be molded at high temperature and high pressure. Further, prolonged exposure to high temperatures is not a good idea from the viewpoint of decomposition of the polyester, and is also economically disadvantageous. therefore.

Interest has been focused on the development of polyester that has good melt moldability and excellent heat resistance, and many proposals have been made.

The present inventors have discovered that an aromatic copolyester made from an aromatic diol component, an aromatic dicarboxylic acid component, and an aromatic oxycarboxylic acid component containing a specific phosphorus atom has excellent heat resistance and good melt moldability. It was discovered that the method had the following properties and was proposed earlier (Japanese Patent Application No. 51691/1982).

Generally, there are three secondary methods for producing this type of aromatic copolyester.

(i) Using the phenolic hydroxyl group as an alkali metal salt.

A method of solution polymerization or interfacial polymerization using a carboxyl group as an acid halide group.

(ii) A method in which a phenolic hydroxyl group is esterified with an acid anhydride of a lower fatty acid and reacted with a carboxyl group.

(iii) A method in which a carboxyl group is esterified with a phenol compound and reacted with a phenolic hydroxyl group.

However, method (i) requires the use of a special and expensive solvent, and also has the problem of requiring separation and purification steps for the copolyester produced.

In addition, in methods (ii) and (iii), the melt viscosity increases rapidly as the degree of double polymerization increases, so it is necessary to first produce a prepolymer with a low degree of polymerization, crush it, and perform solid phase polymerization. did not become. (For example, U.S. Pat. Nos. 3,684,766 and 3,780,
(See specification No. 148).

In addition, in the conventional method, there is a difference in the reactivity of the phenolic hydroxyl group of the aromatic diol component and the reactivity of the phenolic hydroxyl group of the aromatic oxycarboxylic acid component, and the aromatic oxycarboxylic acid component reacts preferentially. However, there was a problem in that a part of this component undergoes block polycondensation to increase the melting point and remain as foreign matter in the resulting copolyester.

(Problems to be Solved by the Invention) The present invention is directed to an aromatic copolyester with excellent heat resistance and less foreign matter, mainly consisting of an aromatic diol component containing a phosphorus atom, an aromatic dicarboxylic acid component, and an aromatic oxycarboxylic acid component. The aim is to provide a method for economically producing .

(Means for solving the problems) The present invention achieves the above objects, and its gist is as follows:
It is as follows.

When producing an aromatic copolyester mainly from an aromatic diol component represented by the following formula, an aromatic dicarboxylic acid component represented by the following formula [2], and an aromatic oxycarboxylic acid component represented by the following formula (2).

First, an aromatic diol component, an aromatic dicarboxylic acid component, and an acid anhydride of a lower fatty acid are reacted at a temperature of 130 to 200°C, and an aromatic oxycarboxylic acid component is added to the reaction mixture at a temperature of 150 to 200°C.
After mixing and reacting at a temperature of 200°C.

A method for producing an aromatic copolyester characterized by carrying out a polycondensation reaction.

R'-0-Ar'-0-R''HOOC-Ar''-COOH■ R30-Ar3-C0OH■ (In the formula, Ar' is a trivalent aromatic group, Ar'' and Ar' are divalent aromatic groups The groups RI, R2, and R3 represent a hydrogen atom or a lower acyl group.However, the aromatic ring may have a substituent.) The copolyester obtained by the method of the present invention can have the following properties depending on the copolymerization composition: It exhibits crystallinity, poor quality, or thermotropic liquid crystallinity, but in order to comprehensively satisfy heat resistance, mechanical properties, and melt moldability.

It is desirable to select a copolymer composition so that thermotropic liquid crystallinity is achieved.

Thermotropic liquid crystallinity refers to the property of polyester molecules regularly aligning in one direction in the molten phase to produce a liquid crystal called a nematic phase, and was confirmed using common polarization techniques using orthogonal polarizers. can.

In the present invention, the first component forming the copolyester is a phosphorus-containing aromatic diol component represented by structural formula [1].

Ar' in formula (2) is preferably a benzene ring or a naphthalene ring. Further, the hydrogen atom of the aromatic ring in Formula 9 (1) is an alkyl group having 1 to 20 carbon atoms.

an alkoxy group, an aryl group having 6 to 20 carbon atoms;

It may be substituted with an allyloxy group or a halogen atom.

A specific example of the phosphorus-containing aromatic diol is the following formula (a):
Although organic phosphorus compounds represented by (d) can be mentioned, the compound (a) is particularly preferably used.

As the aromatic dicarboxylic acid represented by the structural formula [2] which is the second component, terephthalic acid (TPA) and isophthalic acid (IPA) are suitable, and the molar ratio of TPA and IPA is 100/0 to 0. 0/100. Preferably 5/9
5-9515, more preferably 20/80-90/1
0. The optimum ratio is 50,150 to 70/30.

In addition to TPA and IPA, 2,6-naphthalene dicarboxylic acid, naphthalic acid, 4,4'-dicarboxydiphenyl, etc. can also be used.

Further, the third component is an aromatic oxycarboxylic acid component represented by the structural formula (2). Examples of aromatic oxycarboxylic acids include 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, 3-phenyl-4-hydroxybenzoic acid, 2-hydroxy-6-naphthoic acid, 2-hydroxy-5-naphthoic acid, etc. However, 4-hydroxybenzoic acid is particularly preferred.

In addition, components other than the above may be copolymerized within a range that does not impair the heat resistance etc. of the copolyester. Examples of such copolymerized components include resorcinol, hydroquinone,
4.4'-dihydroxydiphenyl, bisphenol A
, ethylene glycol and the like.

Next, as the acid anhydride of lower fatty acid in the present invention,
Examples include acetic anhydride, propionic anhydride, valeric anhydride, pivalic anhydride, and trichloroacetic anhydride, but acetic anhydride is most preferred in terms of boiling point and price.

The components of formula (1) and (2) need to be used in substantially equimolar amounts, and unless this requirement is met, a copolyester with a high degree of polymerization cannot be obtained.

Also, the ratio of the components of Formula 1 ■ and the components of 2〇 is 5 in 1 molar ratio.
/95-95/5, preferably 10/90-80/
20, optimally 30/70 to 50150. If the component of Formula 2 (2) increases beyond these ranges, the strength and heat resistance will decrease, and if the component of Formula 9 (2) increases, the flow start temperature will become too high and the flame retardance will become poor.

In the method of the present invention, first, an aromatic diol component is prepared.

Aromatic dicarboxylic acid component and lower fatty acid anhydride
It is characterized in that the reaction is carried out at a temperature of 30 to 200°C, and an aromatic oxycarboxylic acid component is mixed therewith at a temperature of 150 to 200°C to carry out a single polycondensation reaction.

Next, the method of the present invention will be explained as a preferred example.

9,10-dihydro-9-oxa-10-(2',5') whose aromatic diol component is a phosphorus compound of the formula (a);
-dihydroxyphenyl)phosphaphenanthrene-1
0-oxide (PFIQ) or its diacetate (pH
Q~8).

The aromatic dicarboxylic acid component is TPA/lf'A, and the aromatic oxycarboxylic acid component is 4-hydroxybenzoic acid (411
8A) or its acetate (4HBA-A), a copolyester in which the acid anhydride of lower fatty acid is acetic anhydride (ActO), the manufacturing method thereof will be specifically explained.

(a) An amount equivalent to PIIQ and TPA/IPA and an equivalent amount or more to Pt1Q, preferably 1.05 to 1.25
Charge twice the equivalent amount of ^c20 into the reactor, and under normal pressure, 130 ~
The esterification reaction is usually carried out at a temperature of about 150°C for about 2 hours at 200°C.

In this case, if the degree of one reaction part is less than 130°C, the reaction will not proceed sufficiently, and if it exceeds 200°C, TPA will sublimate, which is not preferable. - To this reaction mixture, at 150-200° C., 4HBA and more than its equivalent, preferably 1.05-1.25 times equivalent of Ac, 0 are mixed under refluxing AczO, and if necessary acetic acid is added under reduced pressure. React while distilling.

If the temperature at this time is less than 150°C, the reaction will not proceed sufficiently,
If the temperature exceeds 200°C, a 4HBA homopolymer will be produced, causing foreign matter, which is not preferable.

(b) Charge an equivalent amount of IPA to PIIQ-8 and TP8 and 0.05 to 0.25 times equivalent of ActO to PIIQ into a reactor, and heat at 130 to 200°C under normal pressure.
The acid exchange reaction is carried out at a temperature of about 50° C. for about 2 hours.

48BA-8 (preferably with Ac20 in an amount of 0.05 to 0.25 times equivalent to 48BA-A) is mixed with the reaction mixture at 150 to 200°C, and the acetic acid is distilled off under reduced pressure if necessary. Make it react.

After the reaction (a) or (b), the temperature is raised and the pressure is reduced sequentially, and finally the copolyester is produced by polycondensation reaction in the melt phase at 250-350°C under a high vacuum of 1 Torr or less for several hours to several tens of hours. can be obtained.

In the polycondensation reaction, the resulting copolyester has an intrinsic viscosity [η] of 1, usually 0.5 or more, preferably 0.6 to 10. Optimally, it is preferable to carry out the process until it reaches 0.7 to 3.0.

If [η] is smaller than 0.5, various mechanical properties such as heat resistance will be inferior, and if [η] is larger than lO, the melt viscosity will become too high and melt moldability will be impaired, which is not preferable. There are times.

To produce a copolyester, a single polycondensation catalyst is usually used, and as the single polycondensation catalyst, one or more compounds selected from various metal compounds and organic sulfonic acid compounds can be used.

As the metal compound, compounds such as antimony, titanium, germanium, tin-9-zinc, aluminum, magnesium, calcium, potassium, sodium, manganese, or cobalt are used.

Examples of organic sulfonic acid compounds include sulfosalicylic acid, 0
- Compounds such as sulfobenzoic anhydride are used;
Dimethyltin maleate and 0-sulfobenzoic anhydride are particularly preferably used.

The amount of catalyst added is usually 0.00% per mole of polyester structural unit. l×10−′ to 100×10−′ mol,
Preferably 0.5X1.0-' to 50X10-' moles,
Optimally, 1X10-' to 10XIO-4 moles are suitable.

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

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

The flow start temperature (Tf) was measured using a flow tester (Fracture CFT-500 model manufactured by Shimadzu) with a diameter of 0.5 mm and a length of 2 mm.
Using a 0 m gouey with a load of 100 kg/c4, the temperature was increased from an initial temperature of 200° C. at a temperature increase rate of 10° C./min, and the temperature was determined as the temperature at which the polymer began to flow out from the die.

The presence or absence of foreign substances was determined by dissolving 0.2 g of polymer in 20 ml of a mixed solvent of equal weight of phenol and tetrachloroethane.
Three degrees were measured using a direct reading haze computer manufactured by Suga Test Instruments Co., Ltd., and evaluated in three ranks of 9th order: A, B, and C. (Rank A is good.) A: Less than 5% at 3 degrees B: 5 to 25% at 3 degrees C: 25 to 100% at 3 degrees
Confirmed using an ettz polarizing microscope.

Examples 1 to 9 A reactor was charged with molar parts of PHQ and TPA/TPA as shown in Table 1.
IPA and Ac, 0. was charged, and dimethyltin maleate was used as a catalyst to process 16 x lO-' mol per 1 mol of PH.

The reaction was carried out under a nitrogen atmosphere at normal pressure and 140° C. for 3 hours while being mixed.

This reaction product was further reacted at normal pressure at 200°C for 2 hours. At 21.200°C, 4HBA and A
CzO was added and mixed. During this time, the temperature of one reactant was 13
After that, the temperature was raised at a rate of 30°C/hr, and after reaching 280°C, the reaction was continued for 2 hours.

Thereafter, the pressure was reduced and the temperature was increased in sequence, and finally polycondensation was carried out at 320° C. for 2 hours under reduced pressure of 1 torr.

The copolyester obtained in Example 8 was crystalline.

The others were thermotropic liquid crystal copolyesters with excellent color tone.

Table 1 shows the characteristic values of the copolyester.

Table 1 Comparative Examples 1 to 2 In Example 1, the reaction temperature of PIIQ, TPA/IPA and AczO was set to 100°C (Comparative Example 1) or 230°C.
As “llll” (comparative example 2), 4HBA and Ac,
When 0 was added and one reaction was carried out, the obtained copolyester had the characteristic values shown in Table 2, and was a thermotropic liquid crystalline copolyester with a considerably large amount of n-components and poor fluidity.

Table 2 Comparative Examples 3-4 In Example 1, 130% of 4HBA and AcgO were added to the reactant of P)I(1, TPA/fPA and Ac, 0.
When the reaction was carried out at 220°C (Comparative Example 3) or 220°C (Comparative Example 4), the obtained copolyester had the characteristic values shown in Table 3 and had poor fluidity with a large amount of foreign matter. It was a thermotropic liquid crystalline copolyester.

Table 3 Comparative Example 5 PHQ, TPA/IPA (molar ratio 22/
3), 4HBA and Ac, 0 (molar parts 25.25.
75.150) was charged, and 16XIO-' mol of dimethyltin maleate was added as a catalyst per 1 mol of PIIQ, and the mixture was reacted with mixing at 140° C. under a nitrogen atmosphere at normal pressure for 3 hours.

This reaction product was further reacted at normal pressure and 200° C. for 2 hours. After that, the temperature was raised at a rate of 30 °C/h, r, and the temperature was increased to 280 °C/h.
After reaching the temperature, the reaction was continued for 2 hours.

Thereafter, the pressure was reduced and the temperature was increased in sequence, and finally polycondensation was carried out at 320° C. for 2 hours under reduced pressure of less than 1 torr.

The obtained copolyester has [η) 2.66, T
Although the color tone was excellent with f297°C and foreign matter rank C, it was a thermotropic liquid crystalline copolyester with a large amount of foreign matter and poor fluidity.

Examples 10 to 14 In Example 1, PHQ was 20 mol parts, and Table 4 shows that copolyesters were prepared in the same manner as in Example 1 except that 5 mol parts of copolymerized or combined components were used with PI ([1]). Obtained.

Table 4 shows the characteristic values of the copolyester.

In Table 4, abbreviations indicate the following compounds.

HQ: Hydroquinone BA: Bisphenol A PET: (η) Polyethylene terephthalate of 0.7 (mol parts are as ethylene terephthalate units) RS Niresorcin 000: 4.4'-dihydroxydiphenyl Example 15 In the reactor, PHQ-A, TPA and AC20 (molar part 25°25.5), and dimethyltin maleate was added as a catalyst at a ratio of 16 x 1 to 1 mole of PHQ-A.
0- 'Mole added.

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

This reaction product was further reacted at normal pressure and 200°C for 2 hours, and then 41188-A and AczO (
molar part 75.5) was added and mixed. During this time, the temperature of one reactant reached 154°C, but the temperature was then increased at a rate of 30°C/hr, and after reaching 280°C, the reaction was continued for 2 hours.

Thereafter, the pressure was reduced and the temperature was increased in sequence, and finally polycondensation was carried out at 320° C. for 2 hours under reduced pressure of 1 torr.

The obtained copolyester has [η) 2.68. T
It was a thermodropink liquid crystalline copolyester with an excellent color tone of f282°C and foreign matter rank A.

Examples 16 to 18 A thermotropic liquid crystal compound was prepared in the same manner as in Example 15, except that diacetates of the phosphorus compounds of formulas (t)), (C), and (d) were used in place of PIIQ-A. Polyester was obtained.

Table 5 shows the characteristic values of the copolyester.

Table 5 Examples 19-20 Example 15 except that diacetates of aromatic oxycarboxylic acids shown in Table 6 were used in place of 4118A-A.
In the same manner as above, a thermodropink liquid crystalline copolyester was obtained.

Table 6 shows the characteristic values of the copolyester.

In Table 6, abbreviations indicate the following compounds.

3HBAl-hydroxybenzoic acid BON6: 2-hydroxy-6-naphthoic acid Table 6 (Effects of the invention) According to the present invention, an aromatic diol component, an aromatic dicarboxylic acid component, and an aromatic oxycarboxylic acid component mainly containing a phosphorus atom Provided is a method for economically producing an aromatic copolyester with excellent heat resistance and less foreign matter from acid components.

Claims (2)

[Claims] (1) Aromatic mainly from aromatic diol component represented by the following formula [1], aromatic dicarboxylic acid component represented by the following formula [2], and aromatic oxycarboxylic acid component represented by the following formula [3] When producing group copolyester, first,
An aromatic diol component, an aromatic dicarboxylic acid component, and an acid anhydride of a lower fatty acid are reacted at a temperature of 130 to 200°C, and an aromatic oxycarboxylic acid component is reacted to a temperature of 150 to 200°C.
A method for producing an aromatic copolyester, which comprises mixing and reacting at a temperature of 0.degree. C., followed by a polycondensation reaction. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [1] HOOC-Ar^2-COOH[2] R^3O-Ar^3-COOH[3] (In the formula, Ar^1 is a trivalent aromatic group, Ar^2 and Ar^3 are divalent aromatic groups, R^1, R^2 and R^
3 represents a hydrogen atom or a lower acyl group. However, the aromatic ring may have a substituent. ) (2) The method for producing an aromatic copolyester according to claim 1, wherein the copolymer composition is selected so that the copolyester becomes a thermotropic liquid crystalline copolyester.