JPS6241220A - Production of copolyester - Google Patents

Abstract

PURPOSE:To obtain a copolyester excellent in heat stability, etc., by reacting a specified oligo- or poly-ester with a hydroxycarboxylic acid, adding an acylating agent and a diol to the reaction system, reacting the resulting mixture and polymerizing the product in a vacuum. CONSTITUTION:5-95mol% (in terms of recurring units of formula I) starting oligoester or polyester comprising recurring units of formula I (wherein R<1> is a 6-20C bivalent aromatic hydrocarbon or the like and R<2> is a 2-40C bivalent aliphatic hydrocarbon or the like) is reacted with 95-5mol% hydroxycarboxylic acid of formula II (wherein R<3> is a 6-20C bivalent aromatic hydrocarbon group forming an aromatic ring). The obtained co-oligomer is acylated with an acylating agent and, before the completion of the acylation, 1-40mol%, based on the acid of formula II, diol of formula III (wherein R<4> is R<1>) is added to the reaction system and is reacted. The reaction mixture is polymerized in a vacuum to obtain the purpose copolyester.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a novel method for producing a copolyester having high elastic modulus and high strength. Since the copolyester produced in this manner forms thermotropic liquid crystals, it can be easily molded and can be commercialized as molding materials, films, and fibers.

[Conventional technology]

In recent years, whether fibers, films or molded products,
There is an increasing demand for materials with excellent rigidity, heat resistance, and chemical resistance. Polyester has come to be widely accepted for use in general molded products, but many polyesters have poor bending modulus and strength, so they have not been suitable for applications that require high modulus and strength. . In order to improve these mechanical properties, it is known to blend charcoal with reinforcing materials such as calcium and glass fiber, but this increases the specific gravity of the material, which reduces the lightweight advantage of plastic. Furthermore, during molding, the molding machine is subject to severe wear, and there are many interlocking points due to dual use.

In recent years, liquid crystalline polyester has attracted attention as a polyester that does not require a reinforcing material and is suitable for applications requiring high elastic modulus and high strength. The Journal of Polymer Science Polymer Chemistry Edition/('
Volume (/974) 2011J page and Special Publication Showa 74-/7
0/ in publication by W, J, Jackson on polyethylene terephthalate and acetoxy rest 1! This was after he announced a thermal liquid crystal polymer consisting of Fe. Among them, Jakunun is
This liquid crystal polymer is more than 1 times more rigid than polyethylene terephthalate, more than Z times more strong, and more than 2t times more powerful! We reported that II & intensity can be used as photons, showing new possibilities for high-performance resins.

On the other hand, we first prepared the general formula (A) 0 〇10-R1-0.0-R2-0- .
・(A) [wherein R1 is a monovalent aromatic hydrocarbon group with 6 to -20 carbon atoms, a monovalent alicyclic hydrocarbon group with 20 to 20 carbon atoms, or/and a monovalent alicyclic hydrocarbon group with a carbon number of -4tO Divalent aliphatic group (
However, the hydrogen atom of the aromatic ring of the aromatic hydrocarbon group may be substituted with a halogen atom, an alkyl or alkoxy group with a carbon number of /~d), and R2 is a divalent aliphatic group with a carbon number of ~d/~d. group hydrocarbon group, a monovalent alicyclic hydrocarbon group having a carbon number of d to -O, a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms forming an aromatic ring (however, an aromatic hydrocarbon group The hydrogen atom of the aromatic ring may be substituted with a halogen atom, an alkyl group or alkoxy group with a carbon number of
tro-rooo polyalkylene oxide - represents a valence radical] is the amount of the repeating units that the raw material oligoenether or polyester consists of! ~the law of nature! Morchi and general formula (B) MO-R31
jOOH・・・・・・・・・(B) [In the formula, RA is a divalent aromatic group having ≦~20 carbon atoms forming an aromatic hydrocarbon ring (however, the hydrogen atom of the aromatic hydrocarbon group may be substituted with a halogen atom, an alkyl group or an alkoxy group having a carbon number of 9
! ~! Molch is reacted to make a copolymerized oligomer (first step), then an acylating agent is added to perform acylation (
1st step), and further polymerization under reduced pressure (3rd step)
An application was filed for a method for producing copolymerized polyester consisting of three steps (%Gan Shoj 9-412246, 1rf-Shoj 9-1
0/672).

In addition, an application has been filed in No. 60-λ0767 for a method that increases the speed of polymerization and significantly reduces the amount of sublimate, but the copolyester produced in this way does not have sufficient thermal stability. Ta.

[Purpose of the invention]

With these points in mind, we conducted extensive research and found a method for producing a copolyester with good thermal stability.

That is, the present invention provides a method for producing a copolyester consisting of the three steps described above, namely, the first step of producing a copolymerized oligomer, the first step of adding an acylating agent to perform acylation, and the third step of polymerizing under reduced pressure. In the method, until the end of the first step, the violet of the diol k (B) represented by the general formula (0) % formula % () (where y is the same fA as R1 in the general formula (A) K) The present invention, which consists in a method for producing a copolymerized polyester characterized by adding and reacting a polyester, will be described in more detail.

The copolymerized polyester expressed by the conventional method is contained in the oligoester produced in the first step. R in formulas (A) and (B)
(synonymous with 2 and R3) is generated, so the terminal group 10H
The balance between the group and the 1000H group is disrupted, and the terminal -COOH group becomes excessive. Therefore, in addition to OH groups, coon groups in copolymers react with acylating agents to form acid anhydride bonds, and terminal carboxylic acids may remain in the final copolymerized polyester. It is thought that polyester has become unstable against heat.

Therefore, in the present invention, the excess 1000H group is eliminated by adding a diol equivalent to or more than that represented by the general formula (0) to the excess -cooH group, and then one-step acylation or acylation is performed. It has now become possible to produce a co-polyester with excellent thermal stability by polymerizing diol while carrying out the above steps and carrying out the xm-polymerization reaction under reduced pressure.

The present invention is carried out by converting the polyester represented by the general formula (A) into polymerization under reduced pressure.More specifically, in order to produce the polyester or oligoester represented by the general formula (A), General formula (H)
Carboxylic acid HOOORI (300H, , , , , , (K) (wherein R' has the same meaning as in general formula (A)) represented by Oyohiso ester is used, but examples of carboxylic acids are shown below. and terephthalate, methoxyterephthalic acid, ethoxyterephthalic acid,
Fluoroterephthalic acid, ric2terephthalic acid, methyl terephthalic acid, isophthalic acid, phthalic acid, methoxyisophthalic acid, diphenylmethane 4t, Q/-dicarboxylic acid, diphenylmethane 3,3'-dicarboxylic acid, diphenyl ether dicarboxylic acid, Shifeni A/
-a, 4t'-dicarboxylic acid, naphthalene--, dicarboxylic acid, naphthalene 1,! Dicarboxylic acid, naphthalene 1, (i (dicarboxylic acid, 7 divic acid, sepacic acid,
Azelaic acid, speric acid, dodecanedicarboxylic acid, 3
-Methyl azelaic acid, glitaric acid, succinic acid, cyclohexane 1,4t dicarboxylic acid, cyclohexane 1,
3-dicarboxylic acid, cyclopentane-1,3-dicarboxylic acid, and the like. These may be used as a mixture, and any one represented by the general formula (IC) can be used.

Also, the general formula (
Specific examples of diol HOR1OH represented by F) (F) (wherein, part is the same as in general formula (A)) include ethylene glycol, 1,J-propanediol, 1,-1 glopanediol, 1,3-butanediol, 1,&-butanediol, neopentyl glycol, 1,6 hexanediol, 1,/J-dodecanediol, cyclohexane 7.4t diol, cyclohexane 1, 3 diols, 1 cyclohexane, 1 cordiol, 1 cyclopenpentane,! - Diol, diethylene glycol, polyethylene glycol, hydroquinone, resorcinol, bisphenol A, methylhydroquinone, chlorohydroquinone, λ,6-naphthalene diol, etc.
These may be used in combination, and any of those represented by general formula (F) can be used.

As the polyester or oligoester represented by the formula (A) used in the present invention, any of those represented by the general formula (A) can be used, but polyethylene terephthalate, polybutylene terephthalate, and their like can be used because of their easy availability. Polyethylene terephthalate and its oligomers are particularly preferred.

As the oxyacid of formula (B), parahydroxybenzoic acid,
Gu-hydroxy 3-chlorobenzoic acid, meta-hydroxybenzoic acid, Hiro-hydroxy 3. j-dimethylbenzoic acid, λ
-oxy6-naphthoic acid, /-oxy! - naphthoic acid,
Examples include /-hydroxy-hiro-naphthoic acid, Schlinger's acid, vanillic acid, and hydroxy-3-methylbenzoic acid. Although it is preferable to use parahydroxybenzoic acid alone in order to maintain melt anisotropy, any oxycarboxylic acid represented by the general formula (B) can be used, or a mixture of these can be used. I don't mind.

Further, the reaction between the oxycarboxylic acid (B) and the polyester and oligoester represented by the general formula (A) is from 100 to
3jθ℃, preferably 220 to 300℃,
What is the reaction? minutes~/θ hours, preferably koθ minutes~! It takes place over a period of time.

The reaction is carried out in such a way that the residual amount of the oxycarboxylic acid compound is usually 70 molar or less, preferably 10 molar or less, based on the charged violet,
Particularly preferably, it is carried out until the concentration becomes 4 tO molti or less.

Although the reaction can be carried out without a catalyst, it can be carried out with the addition of a catalyst if necessary. The diol (0) used in the present invention has the general formula (
Any of those represented by C) can be used; specific examples include hydroquinone, resorcinol, methylhydroquinone, chlorohydroquinone, acetylhydroquinone, acetoxyhydroquinone, nitrohydroquinone, dimethylaminohydroquinone, /β-dihydroxynaphthol, i, r- Dihydroxynaphthol, 1,6
-Syhydroxynaphthol 1.2. <l; -dihydroxynaphthol, 2,7-dihydroxynaphthol, J
, 2/-bis(4t-hydroxyphenyl)propane 1.2. ．． 2'- and su(4t-hydroxy-3,j-dimethylphenylfuropane, λ1.2'-bis(4t-
Hydroxy 3. r-dichlorophenyl)-propane, 2'-bis(terhydroxy-3-methylphenyl)
- Flopane, 2. J-bis(4t-hydroxy-3-
chlorophenyl)propane, bis(couhydroxphenyl-methane, bis(terhydroxy-S,S-dimethylphenyl)-methane, bis(couhydroxyphenyl-methane) 7-3
゜! -dichlorophenyl)-methane, bis(4t-hydroxy-3,z-siphromophenyl)-mefin, 1
,/-bis(terhydroxyphenyl)cyclohexane, y, nail-cyhydroxydiphenylbis(4t-hydroxyphenyl)-kane, bis(4t-hydroxy-3
, z -dimethylphenyl)-ketone, bis(4t-hydroxy-3,5-dichlorophenyl)-1-tone, bis(4t-hydroxyphenyl)nulphite, bis(cuhydroxy-3-chlorophenyl)sulfite, bis(4t- hydroxyphenyl) sulfone, bis(4t-
Hydroxy-3,j-dichlorophenyl) ether, and the like.

The compound represented by the general formula (C) may be added at any time before the end of the first stage, but it is particularly preferable to add it after the end of the seventh stage reaction.

The sumihashi of the compound represented by the general formula (○) is droxycarbon i! It is preferable to use violet/~4tθ morch of (B) equivalent to or more than that of pig iron. The lid can be determined in advance by dividing the reaction solution at the end of the first stage.

If (B) is less than 1 mole, the terminal coon group is still in excess and the purpose cannot be achieved, which is preferable.
If the amount is more than 0 molt, sublimation will increase, which is not favorable.

It is not preferable to add ((') after the completion of the second stage acylation because it may have negative effects such as a decrease in the polymerization rate and the occurrence of sublimation.

As for the addition method, it may be added in bulk, or it may be diluted with a diluent and cooled.

The second step, acylation, uses an acylating agent (acylating agent).
/ ((B) + be done. Contact with acylating agents! Q℃~3! The reaction is carried out at a temperature of Q°C, preferably 100°C to 300°C, more preferably 260°C to 260°C, and may be pressurized.

Alternatively, acylation may be carried out by lowering the temperature of the system to a temperature below the boiling point of the acylating agent. The reaction takes IO minutes or more to IO hours, preferably 20 minutes or more! It takes place over a period of time.

The diol of general formula (0) may be added before the acylation is completed.

In addition, acylating agents include acetic anhydride, propionic anhydride,
Butyric anhydride, benzoic anhydride, etc. are used, but any commonly usable acylating agent can be used, and acetic anhydride is representative among them in terms of reactivity and cost. .

Next, the third stage polymerization is carried out at 200°C to 33-0°C, preferably 20°C to 330°C. In this case, it is preferable to gradually reduce the pressure at the beginning, and
The time required to gradually reduce the pressure to 1IHp is 30
It is important to carry out the pressure reduction gradually for a time of at least 60 minutes, preferably at least 60 minutes, and in particular, to gradually reduce the pressure by /θIJIHt/min to /vxHy/min.

The second and third stages can also be carried out without a catalyst, but may be carried out in the presence of a catalyst if necessary.

Catalysts used in the first, second and third stages include transesterification catalysts, polycondensation catalysts, acylation catalysts,
Decarboxylation catalysts are used, and these may be used in mixtures.

The amount used is relative to the polymer! ~to,oo.

ppm is preferably jO-1000 ppm.

Further, ηinh was measured at θ, j1/lit: 301 in a mixed solution of phenol and tetrachloroethane/nia (weight ratio). The final product has a ηinh of 0.74711 or more, preferably 0.74711 or more. J j #/ # or more.

〔Example〕

The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to the following Examples unless the scope of the invention is lost.

Example 1 mol), 0.37 j mol) as a lid for polyethylene terephthalate oligomer), and stannous acetate O0θ329 were charged, followed by vacuum-nitrogen purging three times, and finally filled with nitrogen. Place under nitrogen flow at a flow rate of Jt/min. When the polymerization tube is immersed in an oil bath at 26θ°C, the FF3W product melts in the bath in about 30 minutes, so stirring is started and transesterification is carried out in the bath for 2 hours to produce a copolymerized oligomer.

After that, heat it up to /4tθ℃ for about 30 minutes and remove the 1-hydroquinone. , 2 j Ii (0.07 j mol) added,
Next, acetic anhydride≦71 (θ, 6 to 7 moles) was added dropwise over 30 minutes, and the mixture was stirred for an additional 7 hours, followed by acylation. After that, the temperature of the oil bath was raised to 22℃ over 2 hours, and zinc acetate dihydrate was added to 0.5℃. Add ti to θ and gradually apply vacuum. Then, after reaching a high vacuum of θ'' and JwH1, 3B# 1 batch is performed.The product is made into chips by breaking the glass polymerization tube, and then dried with pure nitrogen overnight at 73θ℃. The polymer is milky and opaque.
inh -0.76.

Even when this polymer was further vacuum-dried at Vciio DEG C. for 130 hours, it had excellent thermal stability of .eta.inh -0.7.

Furthermore, the results of Engineering R showed that there was no rIR anhydride bond at all.

Example - A glass polymerization tube equipped with a stirring blade, a large nitrogen port, and a decompression port was
-6 hydroxybenzoic acids, λp (o, aj mol) polyethylene terephthalate oligomer (yinh-θ, /
2dl/I) j 7.7.9 (0.30 mol)
Prepare stannous acetate o, oitz, repeat vacuum-nitrogen replacement 3 times, add j[, then cross the quadrant, o, j
When the polymerization tube is placed under a nitrogen flow at a flow rate of t/min and immersed in an oil bath at -60°C, the contents will melt in about 3θ minutes, so start stirring and carry out transesterification for one hour to form a copolymerized oligomer. make. Temporarily, hydroquinone is added to d', 2 j ll (0, θ2 J morn,
Next, acetic anhydride/-+2.4 tl was added dropwise over 30 minutes.
Stirring was continued for another 7 hours to carry out acylation.

After that, the temperature of the oil bath was set to 27. The temperature is raised to tC over 1 hour, 0.0≦♂l of zinc acetate dihydrate is added and vacuum is gradually applied. Then, after creating a high vacuum of 0.3*1iHg, polymerization was carried out for one hour. η of the obtained polymer
inh -0,/7. Even if this polymer was further dried in an oven at 120°C for 100 hours, ηin
It had excellent thermal stability with h -0, J' j.

IR results: No acid anhydride alignment was observed.

Comparative Example: The same procedure as in Example 1 was carried out except that hydroquinone was added.

ηinh w of the produced polymer was 0.2/.

However, when this polymer was vacuum dried at 7-0°C for 72 hours, ηinh = 0. j J, which decreased significantly.

According to the result of ml, the viscosity of sialic acid anhydride is about 1 for the ester bond.
It was present at 0%.

Example 3 Hydroquinone glue F)/C2,2'-bis(4t-hydroxyphenyl)propane (bisphenol A) of Example/Example/Except that 2jJ, I was added.
did the same thing.

The produced polymer had an excellent thermal stability of η1nh-0.70 after drying at 0°C for 20 hours.

As a result of measurement with Engineering R, there was no acid anhydride bond at all.

Example 1 Example 1 except that hydroquinone was added from the beginning
I did the same thing.

The obtained polymer had η1nh-θ, 22.

〔Effect of the invention〕

As described above, according to the method of the present invention, a copolymerized polyester having excellent thermal stability can be obtained.

Applicant: Mitsubishi Kazukyo Co., Ltd. Representative Patent Attorney Hase - Others/names

Claims (6)

[Claims] (1) General formula (A) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・
(A) [In the formula, R^1 is a divalent aromatic hydrocarbon group having 6 to 20 carbon atoms, a divalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, or/and a divalent alicyclic hydrocarbon group having 1 to 40 carbon atoms. Indicates a divalent aliphatic hydrocarbon group (however, the hydrogen atom of the aromatic ring of the aromatic hydrocarbon group may be substituted with a halogen atom, an alkyl or alkoxy group having 1 to 4 carbon atoms), and R^2 is 2 with 2 to 40 carbon atoms
valent aliphatic hydrocarbon group, divalent alicyclic hydrocarbon group having 4 to 20 carbon atoms, divalent aromatic hydrocarbon group having 6 to 20 carbon atoms forming an aromatic ring (however, aromatic hydrocarbon groups having 6 to 20 carbon atoms) The hydrogen atom of the aromatic ring of the hydrogen group may be substituted with a halogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group), or a polyalkylene oxide divalent radical having a molecular weight of 80 to 8000]. The raw material oligoester or polyester consisting of units contains 5 to 95 mol% of the repeating units constituting these units, and the general formula (B) HO-R^3COOH (B) [Formula Middle R^3 is a monovalent aromatic hydrocarbon group having 6 to 20 carbon atoms forming an aromatic ring (however, the hydrogen atom of the aromatic hydrocarbon group is a halogen atom, an alkyl group having 1 to 4 carbon atoms, or A copolymerized oligomer is produced by reacting 95 to 5 mol% of a hydroxycarboxylic acid represented by step), and further polymerization under reduced pressure (third step).
Before the end of the step, a diol represented by the general formula (C) HOR^4OH... (C) (wherein R^4 has the same meaning as R^1 in the general formula (A)) A method for producing a copolymerized polyester, characterized by adding 1 to 40 mol% of (B) and reacting. (2) In formula (A), 60% or more of R^1 is 1,4-
The manufacturing method according to claim 1, which is a phenylene group. (3) The manufacturing method according to claim 1, wherein in formula (A), R^2 is an aliphatic hydrocarbon group having 2 to 6 carbon atoms. (4) The manufacturing method according to claim 1, wherein in formula (A), R^1 is a 1,4 phenylene group (5) The manufacturing method according to claim 1, wherein in formula (A), R^2 is an aliphatic hydrocarbon group having 2 carbon atoms. (6) The manufacturing method according to claim 1, wherein R^3 in formula (B) is a 1,4 phenylene group