JP3022700B2 - Manufacturing method of aromatic polyester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a crystalline polyester polymer. More specifically, excellent heat resistance,
The present invention relates to a method for efficiently producing an optically isotropic crystalline aromatic polyester polymer having flame retardancy, mechanical properties and moldability.

[0002]

2. Description of the Related Art Various types of aromatic polyesters can be obtained from amorphous polymers, crystalline polymers and liquid crystalline polymers depending on the combination or composition of the constituent components. Among these, amorphous polymers are excellent in dimensional stability, transparency, mechanical properties, and heat resistance, and liquid crystalline polymers are excellent in fluidity, mechanical properties, heat resistance, and solvent resistance. Has been put into practical use. On the other hand, although crystalline polymers are excellent in heat resistance, mechanical properties, solvent resistance, slidability, and rigidity, there are only a few studies on crystalline aromatic polyesters.

[0003] One reason for this is the production method. In the case of an amorphous polyester, since a solvent that dissolves the polymer is generally present, polymerization using a reaction solvent is possible, and it does not crystallize and solidify. Uses a melt polymerization method. In most cases, a liquid crystalline polyester is formed by a melt polymerization method utilizing its fluidity. By the way, optical isotropic (non-liquid
( Crystalline ) crystalline polyesters have good solvent resistance, so a good reaction solvent cannot be found or they usually have a high melting point. The production was difficult because it was difficult to obtain a polymer having a degree of polymerization.

Such an optically isotropic crystalline wholly aromatic poiy
JP-A-5-5024 discloses a method for producing a ester.
Include isophthalic acid, hydroquinone and certain aromatic di
Starting material consisting of hydroxy compound and phenol
Used, firstly phenol is a difficult condition was distilled off out of the system, more than 50% of the carboxyl groups of the starting material until the esterification, carried out generated water while distilling out of the system,
Then, a method for producing a crystalline aromatic polyester polymer which is carried out while distilling phenols and generated water out of the system to obtain a polymer having a desired degree of polymerization is disclosed.

Thus , dicarboxylic acids and aromatic dihydrides
In the method of directly esterifying a proxy compound, the high degree of polymerization of the polymer is obtained in an inexpensive raw material, sublimate high melting point formed in the reaction for esterification rate can not be obtained sufficiently high In some cases, it is necessary to use a reaction device, or there may be a problem in a continuous process. Further, there is a problem that a polymer having the same composition as that produced by the phenyl ester method has a higher heat resistance and a polymer having good crystallinity is hardly obtained. In addition, the aliphatic
High polymerization degree when
Another problem is that it may be difficult to obtain a polymer.
You.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to obtain an aromatic polyester polymer having excellent crystallinity (easy to be crystallized) by industrial melting only by a melt polycondensation reaction. It is an object of the present invention to provide a method which can be produced very advantageously. Another object of the present invention, when it is difficult to obtain a high degree of polymerization of the polymer, such as including an aliphatic diol component and diphenyl Bruno Lumpur components also industrially only by melt polycondensation reaction into the polymer structure It is an object of the present invention to provide a method capable of producing an aromatic polyester very advantageously. Still other objects and advantages of the present invention will become apparent from the following description.

[0007]

Means for Solving the Problems The present inventors have made intensive studies.
As a result, certain aromatic dicarboxylic acids , hydroquinone,
After performing an esterification reaction directly using an aliphatic dihydroxy compound and a phenol, a diaryl carbonate is added to the reaction system and a polymerization reaction is carried out, which is equivalent to a case where a phenyl ester of dicarboxylic acid is used as a raw material. It has been found that an excellent polymer having heat resistance and crystallinity can be produced cost-effectively, and that the problems of sublimation generation and the degree of polymerization of polyesters containing aliphatic diols as components can be solved. Was.

That is, the process for producing an aromatic polyester according to the present invention is substantially constituted by the components of the following formulas (I), (II) and (III), and comprises the components (II) and (II)
In producing an aromatic polyester having an equivalent ratio of I) of 60/40 to 90/10,

[0009]

Embedded image

[In the formula (III) , R represents an aliphatic hydrocarbon group having 2 to 20 carbon atoms. ]

[0011] isophthalic acid or isophthalic acid aromatic dicarboxylic acid as a main acid components (a), hydroquinone (b), aliphatic dihydroxy compound represented by the following formula (IV) (c) and phenol compound (d ) Is replaced by HO—R—OH (IV) [ R in the formula (IV) is the same as R in the formula (III). ] The following formula
(1 ), (2) and (3) 1.3 ≧ (B + C) /A≧0.9 (1) 90/10 ≧ B / C ≧ 60/40 (2) D / A ≦ 10 ( 3) [In the above formulas (1), (2) and (3) , A represents an aromatic dicarboxylic acid (a), B represents hydroquinone (b), and C represents a fatty acid.
Aliphatic dihydroxy compounds (c) and D are moles of phenols (d). ] At the same time,
After a heat-melting reaction in the presence of an esterification catalyst to produce an esterified product having an esterification reaction rate of 50 to 95% , 70 to 10 mol per 100 mol of unreacted -COOH group.
0 molar equivalents of diaryl Lumpur carbonate was added and allowed to further heat melting is the preparation of aromatic polyester, characterized in that to produce the aromatic polyesters the intrinsic viscosity is in the range of 0.4 to 1.5 .

The aromatic dicarboxylic acid (a) used in the method of the present invention is isophthalic acid or an aromatic dicarboxylic acid containing isophthalic acid as a main acid component. Other aromatic dicarboxylic acids used as a secondary acid component together with isophthalic acid include, for example, terephthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid, diphenyl Sulfone dicarboxylic acid and the like can be mentioned as preferred. Such minor acid component can account for no more than 20 mole percent, and preferably no more than 10 mole percent, of the total aromatic dicarboxylic acid.

In the present invention, at least hydroquinone (b) and the aliphatic dihydroxy compound (c) represented by the above formula (IV) are used as the raw material dihydroxy compound.

An aliphatic hydroxy compound represented by the formula (IV)
Things as the, neopentyl glycol, ethylene glycol, pentylene glycol, 2-methyl-2-ethyl-1,3-propanediol can be examples Shimesuru. Of these neopentylene glycol is particularly preferred.

In the method of the present invention, the compound (a),
(B) and (c) satisfy the following two relational expressions: 1.3 ≧ (B + C) /A≧0.9 (1) 90/10 ≧ B / C ≧ 60/40 (2) Used in such quantitative proportions. In these formulas, A is the number of moles of the aromatic dicarboxylic acid (a), B is the number of moles of the hydroquinone (b), and C is the number of moles of the aliphatic dihydroxy compound (c) represented by the formula (IV).

The aliphatic dihydrogen represented by the formula (IV)
The xy compound (c) may be used in combination of two or more kinds, but also in that case, the above formula (1) is used in the total amount of (c).
(2) needs to be satisfied. The above equation how (1)
Represents an aromatic dicarboxylic acid (a) and an all dihydroxy compound [ie, hydroquinone (b) and an aliphatic dihydroxy
Compound (c)] should be used in an appropriate balance to form a polymer chain. That is , when the formula (1) is not satisfied, the degree of polymerization of the polymer is hard to increase, and coloring or the like is easily caused at the time of the polymerization reaction.

The following relational formula (1a) is preferably established between the compounds (a), (b) and (c). 1.2 ≧ (B + C) /A≧1.0 (1a)

The lower formula (2) shows that hydroquinone (b) and
It is intended to define the ratio of the polymerized unit derived from the aliphatic dihydroxy compound (c). That is, when the molar ratio B / C of the hydroquinone (b) and the aliphatic dihydroxy compound (c) exceeds 90/10, the melting point of the obtained polymer becomes too high, and melt polymerization and molding become difficult. Not preferred. This value is 60/4
If it is less than 0, the crystallinity of the polymer decreases, which is not preferable.

Hydroquinone (b) and the compound represented by the above formula (IV)
It is preferable that the following relational expression (2a) holds between the aliphatic dihydroxy compounds (c) to be formed, and it is particularly preferable that the relational expression (2b) holds. 90/10 ≧ B / C ≧ 70/30 (2a) 85/15 ≧ B / C ≧ 70/30 (2b)

In the method of the present invention, the compound (a),
Phenols (d) are used in addition to (b) and (c).

The phenols (d) include carbon
Substituted with an alkyl group of the formulas 1 to 5 or a phenyl group
Phenols that can be used include, for example, phenol, m-cresol, p-cresol, p-butylphenol, p-amylphenolphenylphenol and the like. Of these, phenol, cresol and o-phenylphenol are more preferred, and phenol is particularly preferred.

These phenols (d) are not used as constituents of the wholly aromatic polyester polymer to be produced, but are used for the reaction between the compounds (a), (b) and (c). At the beginning of the reaction. The use of phenols results in a faster reaction, less decomposition of the reaction product, and less coloring .

The preferred amount of the phenol (d) used is based on the relational formula: D / A ≦ 10 [A is the number of moles of the compound (a) and D is the number of moles of the phenol (d)] with respect to the compound (a). Such a quantitative ratio, more preferably, the relational expression: 4
≧ D / A ≧ 0.2 is satisfied, and particularly preferably, the relational expression:
It is used in such a ratio that 2 ≧ D / A ≧ 0.3 is satisfied.

In the method of the present invention, the compound (a),
(B), (c) and the phenol (d) are heated and melted in the presence of an esterification catalyst. Examples of the esterification catalyst include antimony trioxide, stannous acetate,
Dibutyltin oxide, germanium oxide, titanium tetrabutoxide and the like are preferably used.

During the heating and melting, an esterification reaction and a transesterification reaction proceed to form an aromatic polyester polymer.
I do . The heat melting reaction, polycondensation reaction and the initial reaction (esterification) (hereinafter, the polymerization reaction that) it is convenient will be described separately with.

In the present invention, this initial reaction and subsequent
Between the can carried out the polymerization reaction, substantially equimolar to unreacted components the diaryl Lumpur carbonate, i.e., an important feature is to add 70 to 100 molar equivalents to carboxylic acid residues 100 moles of unreacted It is.

[0027] As the diaryl Lumpur carbonates, mention may be made, for example diphenyl carbonate or bis (4-methylphenyl) carbonate, bis (o-phenylphenyl) diaryl Lumpur carbonate having a substituent such as carbonates. Of these, diphenyl carbonate is particularly preferred.

The initial reaction and the polymerization reaction will be described in the following order.

In the initial reaction, 50 to 95% of the carboxyl groups of the aromatic dicarboxylic acid (a) are hydroxyl components [ie, hydroquinone (b) , aliphatic dihydroxy compound].
Things (c), a step of esterification by reacting with phenol compound (d)]. At this stage, water is generated by the reaction, and is distilled out of the reaction system. At this stage, it is necessary to prevent the hydroxy component from distilling out of the reaction system.

The reaction temperature of the initial reaction varies depending on the catalyst, but is preferably 150 ° C. or higher. It is more preferably at least 180 ° C, particularly preferably at least 230 ° C. The reaction temperature is preferably raised as the reaction proceeds. A preferred upper limit in this case is 330 ° C., and more preferably about 300 ° C.

The initial reaction can be carried out under normal pressure to pressurization. When the reaction temperature is particularly increased as compared with the boiling point of the compound represented by the formula (IV) and the phenols (d), the reaction is preferably performed under pressurized conditions. The reaction system is preferably set in an atmosphere of an inert gas such as nitrogen or argon.

The reaction time may be a time sufficient for the above-mentioned ester reaction to proceed sufficiently, and this time varies depending on the reaction time, the reaction scale and the like. Preferably 3
It is about 0 minute to 20 hours, more preferably about 1 to 10 hours.

In the initial reaction, it is preferable to remove water generated by the esterification out of the reaction system. The esterification reaction is an equilibrium reaction, and the reaction proceeds as the generated water is removed out of the system, thereby improving the yield and purity of the product. The generated water can be removed out of the reaction system by the difference in boiling point with the phenol (d), but it can also be removed out of the reaction system by azeotropy using an organic solvent that forms an azeotropic mixture with water. it can. The organic solvent may be any organic solvent which does not decompose itself under the reaction conditions, is substantially stable in the reaction system, and azeotropes with water. In particular,
Aromatic hydrocarbons such as toluene, xylene and ethylbenzene can be preferably used.

The conversion of the esterification reaction in the initial reaction is 50 to 95% . This esterification reaction rate can be known from the amount of water generated by the reaction, but in order to obtain it more accurately, it can be obtained by extracting a part of the reaction product and measuring the unreacted -COOH value. .
The esterification rate in the initial reaction is more preferably 60
To 95%, particularly preferably 70 to 95%.

[0035] After the above-described initial reaction, to determine the diaryl Lumpur carbonate amount the amount or the unreacted -COOH value of the generated water based. Unreacted -COO in terms of accuracy
It is preferable to obtain from the H value.

The amount of the diaryl carbonate added is 70 to 100 molar equivalents relative to 100 mol of unreacted COOH groups .
And Good Mashiku is 75 to 95 molar equivalents. In less than 70 molar equivalents, less the effect of the addition of diaryl Lumpur carbonate, undesirably easily lead to solidification of the carbonate bond are many remaining easy coloring and during polymerization in the polymer in 100 or more molar equivalents.

[0037] The diaryl Lumpur carbonate, in the next polymerization reaction, supplement esterification of the unreacted is consumed,
Smoothly allowed to proceed polymerization reaction significantly contributes to obtaining good polymer.

[0038] As diaryl Lumpur carbonate addition method may be charged After lowering the temperature after the initial reaction, the diaryl Lumpur carbonate remains in the initial reaction temperature may be added to the reaction system, under conditions such as air is not mixed It is preferable to carry out in.

The subsequent polymerization reaction, further simultaneously esterification proceeds, is the step of reaction proceeds polycondensation proceeds with it until the resulting esters with hydroxy component and diaryl Lumpur carbonate was added. At this stage, carbon dioxide, water and phenols are produced. Water and phenols are distilled out of the reaction system. Diaryl Lumpur carbonate at this stage reacted with the unreacted -COOH, carbon dioxide, water, and generates a phenol, has helped improve the esterification rate.

The reaction is preferably carried out at an initial reaction temperature to 380 ° C. It is necessary to carry out the polymerization reaction while the polyester is being melted. Since the melting point of the reactant rises as the polymerization proceeds, it is preferable to carry out the reaction while gradually increasing the temperature.
Up to about 5, preferably at a temperature of about 230 to 340 ° C. In the case of a higher intrinsic viscosity, the melt polymerization is preferably performed at a temperature of 340 to 380 ° C, more preferably 340 to 360 ° C. At this time, the phenols (d) are recovered and reused.

[0041] The diaryl Lumpur carbonate in the polymerization reaction also react, carbon dioxide, water, phenols produced. -COOH of diallyl Lumpur carbonate unreacted
Due to the reaction with the group, the sublimate having a high melting point is suppressed, and the polymerization reaction proceeds more smoothly.

When the degree of polymerization of the aromatic polyester obtained by the method of the present invention is to be increased, it is preferably carried out in an extruder type reactor or the like.

The polymerization reaction is carried out under reduced pressure or by flowing an inert gas to forcibly generate water and phenols as a result of the reaction,
In addition, if necessary, it is advantageous to carry out the reaction while removing excessively used dihydroxy aromatic compounds such as hydroquinone outside the reaction system.

Thus, according to the method of the present invention, an aromatic polyester polymer having an intrinsic viscosity of 0.4 to 1.5 can be obtained only by melt polymerization. Preferred intrinsic viscosity is 0.45
1.0, and more preferably 0.5 to 1.0.

The method of the present invention is preferably carried out in the presence of a heat stabilizer. As such a heat stabilizer, various phosphorus compounds are preferable. Preferred examples of such phosphorus compounds include phosphorous acid, phosphoric acid, triphenyl phosphite, triphenyl phosphate, triphenyl phosphine, and the like. The preferred amount of such a stabilizer is 0.0 to the aromatic dicarboxylic acid component (a).
About 01 to 1 mol%, more preferably 0.01 to 0.5%
It is about mol%. Furthermore, addition timing, it between the polymerization reaction initial reaction preferably.

The crystalline aromatic polyester polymer according to the present invention is optically isotropic in the molten state and can be extruded,
Normal melt molding such as injection molding is possible. Moreover, the molded product obtained by melt-molding the polyester polymer,
This aromatic polyester polymer is not only excellent in mechanical properties, dimensional stability, heat resistance, chemical resistance, flame retardancy, but also has low water absorption, so this aromatic polyester polymer is used as a material for engineering plastics, fibers, films, etc. Extremely useful.

[0047]

As described above, according to the method of the present invention, an inexpensive raw material is used, and an excellent crystal similar to that obtained when an expensive raw material such as phenyl isophthalate is used only by a melt polymerization method. It is possible to produce an aromatic polyester having good heat resistance and heat resistance and color tone. That is, according to the present invention, a polymer having a short crystallization time, a high crystallization temperature upon cooling from a molten state, and a short half-crystallization time can be obtained. Therefore, when the aromatic polyester produced by the method of the present invention is used as a raw material for molding , it is possible to improve the productivity and obtain a molded product having a good color tone by shortening the molding cycle. Becomes In addition, the sublimate which has been a problem in the manufacturing process
Generation is suppressed. It may also contain aliphatic structures.
High degree of polymerization can be obtained
You.

[0048]

The present invention will be described below in detail with reference to examples. In the examples, simply “parts” means “parts by weight”, and the intrinsic viscosity of the polymer (Inherent Viscosit) is used.
y) is a value measured using a phenol / tetrachloroethane mixed solvent (weight ratio 60/40) at a concentration of 0.3 g / dl and a temperature of 35 ° C. Further, the melting point (Tm) and the second transition point (Tg) of the polymer, and the crystallization temperature Td from the melted state,
c was measured at a rate of 10 ° C./min for both heating and cooling rates using DSC. The melt viscosity was measured using a flow tester.
It measured at 100 degreeC, and showed the value of shear rate 1000 / sec. The crystallization rate of the polymer is measured by depolarization intensity method, and the time during which crystallization proceeds half (half crystallization time) is measured by jumping from the melting state at 390 ° C. to each crystallization temperature and temperature. It was used as a guide to the rate of formation.

Example 1 166 parts of isophthalic acid, 91 parts of hydroquinone, 21 parts of neopentylene glycol, 94 parts of phenol and 0.09 part of antimony trioxide were charged into a reactor equipped with a stirrer distillation system (isophthalic acid). The molar ratio of acid / hydroquinone / neopenthylene glycol / phenol is 100/83 /
20/100), the system was replaced with nitrogen, and then 280 under nitrogen pressure.
Heated to ° C. Pressure from 8 kg / cm ² to 2 kg / cm ²
The reaction was continued for 10 hours while gradually lowering the temperature and while distilling off water generated by the reaction outside the system. During this period, 28 parts of water were produced (esterification reaction rate: 78%). Thereafter, unreacted phenol was expelled from the system. The terminal -COOH group of this reaction mixture was measured to be 1760 (equivalent / T) (the calculated esterification reaction rate was 75%).

Then, the reaction system was returned to normal pressure, 83 parts of diphenyl carbonate and 0.33 part of triphenyl phosphite were added, and the reaction was carried out for 180 minutes while distilling off volatile components out of the system in a nitrogen stream. During this time, the reaction temperature was 280
C. to 340.degree. Next, the inside of the system was gradually reduced in pressure, and after 60 minutes, under a high vacuum of about 0.5 mmHg, and the reaction was further performed for 60 minutes to obtain a polymer.

Each reaction proceeds smoothly, and problems such as generation of sublimates occur.
Was not seen. The resulting polymer has an intrinsic viscosity of 0.5
3, a polymer having good crystallinity of Tm 348 ° C., Tg 134 ° C., and Tdc 284 ° C. The half-crystallization time of this polymer is about 3 at a crystallization temperature of 150 to 180 ° C.
5 seconds.

[Comparative Example 1] After the initial reaction, the same reaction as in Example 1 was performed without adding diphenyl carbonate. As a result, the obtained polymer had an intrinsic viscosity of 0.51, a Tm of 342 ° C, and a Tg of 131.
° C and Tdc of 252 ° C. The half-crystallization time of this polymer was a minimum of 5.5 seconds at a crystallization temperature of 170 ° C, and no crystallization was observed below 160 ° C.

Example 2 Next, an L / D 42 having two vent ports capable of vacuuming at two locations
Using a 30mmφ co-rotating biaxial extruder
The polymer obtained in Example 1 was heated at a polymer temperature of 350 to
The melt reaction was performed under the conditions of 360 ° C., a screw rotation speed of 100 rpm, and an average residence time of about 10 minutes in a vacuum zone.
At this time, a screw section opposite to a normal conveying screw was provided at the front of each vent port to seal the vacuum zone, thereby keeping the two vent ports at a vacuum of about 1 mmHg.

The polymer thus obtained has good crystallinity, an intrinsic viscosity of 0.62, a Tm of 348 ° C., and a Tg of
140 ° C., Tdc 292 ° C., half-crystallization time 160-1
It took about 4.5 seconds at 70 ° C.

Comparative Example 2 166 parts of isophthalic acid, 91 parts of hydroquinone, 21 parts of neopentylene glycol, diphenyl carbonate 4
28 parts and 0.09 part of antimony trioxide were charged into a reactor equipped with a stirrer distillation system (molar ratio of isophthalic acid / hydroquinone / neopenthylene glycol / diphenyl carbonate was 100/83/20/200). The reaction was carried out for 180 minutes in a nitrogen stream while distilling volatile components out of the system. During this time, the reaction temperature rose from 200 ° C to 340 ° C. Next, gradually reduce the pressure inside the system,
After 60 minutes, a high vacuum of about 0.5 mmHg was applied, but soon the reaction solidified and only a low-molecular-weight compound having a high melting point was obtained.

As shown in the above Examples and Comparative Examples, the aromatic polyester produced by the method of the present invention has excellent crystallinity. In addition, it can be seen that a good polymer can be produced even though an aliphatic diol is contained as a constituent unit in the polymer chain.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08G 63/00-63/91

Claims (1)

(57) [Claims] 1. The composition of the present invention is substantially constituted by the components of the following formulas (I), (II) and (III), and the content equivalent ratio of the components (II) and (III) is 60/40 to 90/10. In the production of the aromatic polyester, [In the formula (III), R represents an aliphatic hydrocarbon group having 2 to 20 carbon atoms. Isophthalic acid or isophthalic acid aromatic dicarboxylic acid as a main acid components (a), hydroquinone (b), aliphatic dihydroxy <br/> shea compound represented by the following formula (IV) (c) and phenol The class (d) is represented by the following formula : HO-R-OH (IV) wherein R is an aliphatic hydrocarbon having 2 to 20 carbon atoms.
Represents a group ] The following formulas (1), (2) and (3) 1.3 ≧ (B + C) /A≧0.9 (1) 90/10 ≧ B / C ≧ 60/40 (2) D / A ≦ 10 (3) [In the formulas (1), (2) and (3), A is an aromatic dicarboxylic acid (a), B is hydroquinone (b), C is an aliphatic dihydroxy compound (c), and D is This is the number of moles of each of the phenols (d). At the same time, the esterification reaction rate is 50 to 95% by heating and melting in the presence of a catalyst.
After the formation of an esterified product of the unreacted —COOH group 1
A diaryl carbonate in an amount of 70 to 100 mole equivalents per 100 moles is added and further heated and melted to form an aromatic polyester having an intrinsic viscosity in the range of 0.4 to 1.5. Manufacturing method.