JPH1087802A - Production of copolyester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a copolyester having an excellent heat resistance by reacting an aromatic dicarboxylic acid under heating with an aromatic glycol, adding specified amounts of an aromatic dihydroxy compound and an alkylene carbonate to the reaction system and melt-reacting the entire mixture in the presence of a catalyst. SOLUTION: Equivalents (a) of an aromatic dicarboxylic acid (e.g. terephthalic acid) and equivalents (b) of an aliphatic glycol (e.g. ethylene glycol) in amounts satisfying formula I and lithium acetate catalyst are placed in a reactor, agitated under heating in a nitrogen atmosphere and reacted till water in an amount corresponding to a degree of esterification of 80% or above is distilled off. The pressure in the reaction system is brought to ordinary pressure to obtain a polyester oligomer. To this oligomer, equivalents (c) of an aromatic dihydroxy compound (e.g. 2,2-bis(4-hydroxyphenyl)propane) and equivalents (d) of five- or six-membered alkylene carbonate (e.g. propylene carbonate) in amounts satisfying formulas II and III (wherein (e) is the degree of esterification after the reaction) are added, and the entire mixture is molten by heating to 150-260 deg.C in the presence of Na2 CO3 catalyst and reacted till 150mol% or more CO2 is produced to obtain a copolyester.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a copolymerized polyester, and more particularly to a novel method for producing a copolymerized polyester comprising a hydroxyalkyl ether of an aromatic dihydroxy compound as a glycol component.

[0002]

2. Description of the Related Art Polyesters containing an aromatic dihydroxy compound (bisphenol) as a diol component, so-called polyarylate, have high heat resistance and are used as engineering plastics. But phenolic OH
Is much lower in reactivity than aliphatic OH, and it is substantially impossible to copolymerize this bisphenol with a polyester such as polyethylene terephthalate containing an aliphatic glycol as a diol component. Therefore, bisphenol is converted to hydroxyalkyl ether to form phenolic OH.
Is an aliphatic OH, and various polyesters using this as a copolymerization component have been proposed.

For example, JP-A-2-269364, JP-A-4-42161, and JP-A-5-9278 disclose hydroxyalkyl ethers of 2,2-bis (4-hydroxyphenyl) propane. It is disclosed that polyester is useful as a resin for toner. JP-A-6-49186 and JP-A-6-157
No. 730 and the like disclose that a polyester obtained by copolymerizing a hydroxyalkyl ether of 9,9-bis (4-hydroxyphenyl) fluorene is excellent in heat resistance, optical properties, moldability and the like. For the production of these polyesters, the corresponding hydroxy ethoxy ethers of bisphenols are used.

[0004] The hydroxyethoxy ether of bisphenol must first be separately synthesized. This synthesis is usually carried out by reacting bisphenol with an oxirane such as ethylene oxide or propylene oxide, but this reaction is complicated and has many problems such as extremely high toxicity of ethylene oxide. Further, the obtained hydroxyalkyl ether of bisphenol usually contains by-products to which two or more oxiranes are added, but removing this by a method such as distillation would increase the boiling point of the target product. Therefore, it is practically impossible.
Also, depending on the type of bisphenol used, purification of the product by recrystallization or the like is often difficult because the crystallinity of the product is generally low. For this reason, there has been a problem that the polymer cannot be used as a monomer for polymerization, or the cost of the polymer is high even when it can be used.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel method for producing a polyester obtained by copolymerizing a hydroxyalkyl ether of bisphenol without the above-mentioned problems. Another object of the present invention is to provide a novel method for producing a polyester obtained by copolymerizing a target bisphenol hydroxyalkyl ether using bisphenol as a raw material for polymerization without using a hydroxyalkyl ether of bisphenol. It is in.

[0006]

An object of the present invention is to provide an aromatic dicarboxylic acid (A) represented by the following formula (1) in an amount satisfying the following formula (5) and a fat represented by the following formula (2). A group glycol (B) is reacted with (A) by heating until the esterification ratio becomes 80% or more, and then the following formula (3)
Is added to the aromatic dihydroxy compound (C) represented by the following formula (4) and the 5- or 6-membered alkylene carbonate (D) represented by the following formula (4) in an amount satisfying the following formulas (6) and (7). And a melt reaction in the presence of a catalyst until carbon dioxide gas is generated in an amount of 150 mol% or more based on the amount of the aromatic dihydroxy compound (C). it can.

[0007]

Embedded image

[In the formula (1), Ar ₁ represents an aromatic residue having 6 to 12 carbon atoms. In the formula (2), R ₁
Represents alkylene having 2 to 6 carbon atoms. In the formula (3), Ar ₂ is an aromatic residue having 6 to 12 carbon atoms or —Ar ₃ —X—Ar ₃ — (where Ar ₃ has 6 to 12 carbon atoms).
Aromatic residues 12, X is _{-C (CH 3) 2 -,} - O
-, - CO -, - SO 2 -, - S- or a divalent residue of good 1 to 15 carbon atoms optionally containing heteroatoms. ). In the formula (4), R ₂ represents an alkylene having 2 to 5 carbon atoms in which a cyclic carbonate structure forms a 5- or 6-membered ring. ]

[0009]

1 ≦ b / a ≦ 2 (5) 0.01a ≦ c ≦ 0.99a (6) 1.8c + 2a (1-e / 100) ≦ d ≦ 3.0c + 2a (1-e / 100) ( 7) [In formulas (5), (6) and (7), a, b, c
And d indicate the number of equivalents of the components A, B, C and D, respectively. e indicates the esterification rate (%) after the reaction between the component A and the component B. ]

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. In the aromatic dicarboxylic acid (A) represented by the above formula (1), Ar ₁ represents an aromatic residue having 6 to 12 carbon atoms.
Specifically, p-phenylene, m-phenylene, 2,
6-naphthylene, 2,7-naphthylene, 4,4′-biphenylene and the like can be mentioned. Specific aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, Examples thereof include 2,7-naphthalenedicarboxylic acid and 4,4'-diphenylcarboxylic acid. Of these, terephthalic acid, isophthalic acid, and phthalic acid can be preferably used.

In the aliphatic glycol (B) represented by the above formula (2), R ₁ represents an alkylene having 2 to 6 carbon atoms. Specific examples of the glycol (B) include ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, neopentylene glycol, hexamethylene glycol, cyclohexanedimethanol, and 2,2′-bis (4-hydroxycyclohexyl). Propane and the like can be mentioned. Of these, ethylene glycol and tetramethylene glycol are preferred.

In the aromatic dihydroxy compound (C) represented by the above formula (3), Ar ₂ has 6 to 12 carbon atoms.
An aromatic residue or —Ar ₃ —X—Ar ₃ —. Examples of the aromatic residue having 6 to 12 carbon atoms include p-phenylene, m-phenylene, 2,6-naphthylene, 2,7-naphthylene, 1,5-naphthylene, and 4,4′-biphenylene. it can. Ar ₃ is an aromatic residue having 6 to 10 carbon atoms which may be substituted with halogen, and X represents —C (CH ₃ ) ₂ —, —O—, —CO—, or —SO
₂ -, - selected from the group consisting of divalent residue of S- and heteroatom optionally having 1 to 15 carbon atoms be contained.
A divalent residue having 1 to 15 carbon atoms refers to an alkylene group,
Examples thereof include an alkylaryl group.

Here, the aromatic dihydroxy compound (C)
Specifically, hydroquinone, resorcinol,
2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,
4-dihydroxynaphthalene, 4,4′-dihydroxydiphenyl, 2,2′-dihydroxydiphenyl, 3,
3'-dihydroxydiphenyl, 2,2-bis (4-hydroxyphenyl) propane, 1,4-bis (4-hydroxyphenyl) benzene, 2,2-bis (4-hydroxyphenyl) perfluoropropane, bis (4 -Hydroxyphenyl) ether, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfide, 4,4′-dihydroxybenzophenone, 2,2
-Bis (4-hydroxyphenyl) butane, bis (4-
(Hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethyl -Cyclohexane, 1,1-bis (4-hydroxyphenyl) -1
-Phenylethane, 1,1-bis (4-hydroxyphenyl) -1,1-diphenylmethane, 9,9-bis (4
-Hydroxyphenyl) -fluorene, phenolphthalein, phenolsulfonephthalein, 2,2-bis (4-hydroxy-3-methyl-phenyl) propane,
2,2-bis (4-hydroxy-3-chloro-phenyl) propane, 2,2-bis (4-hydroxy-3-bromo-phenyl) propane, 2,2-bis (4-hydroxy-3-t- Butyl-phenyl) propane, 2,2-
Bis (4-hydroxy-3-ethyl-phenyl) propane, 2,2-bis (4-hydroxy-3-propyl-phenyl) propane, 2,2-bis (4-hydroxy-3
-Isopropyl-phenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethyl-phenyl) propane, 2,2-bis (4-hydroxy-3,5-dichloro-phenyl) propane, 2,2 -Bis (4-hydroxy-3,5-dibromo-phenyl) propane, bis (4
-Hydroxy-3-chloro-phenyl) sulfone, bis (4-hydroxy-3-bromo-phenyl) sulfone,
Bis (4-hydroxy-3,5-dichloro-phenyl)
Sulfone, bis (4-hydroxy-3,5-dibromo-
Phenyl) sulfone, 1,4-bis (4-hydroxyphenoxy) benzene, 1,3-bis (4-hydroxyphenoxy) benzene, 4,4′-bis (4-hydroxyphenoxy) diphenyl, 1,4-bis ( 3-hydroxyphenoxy) benzene, 4,4′-bis (3-hydroxyphenoxy) diphenyl, 1,4-bis {p-hydroxy-α-cumyl} benzene, 1,3-bis {p-hydroxy-α-cumyl ｝ Benzene and the like can be mentioned.

In the alkylene carbonate (D) represented by the above formula (4), R ₂ is an alkylene having 2 to 5 carbon atoms whose cyclic carbonate structure forms a 5- or 6-membered ring. Specific examples of the alkylene carbonate (D) include ethylene carbonate, propylene carbonate, trimethylene carbonate, and neopentylene glycol cyclic carbonate. Of these, ethylene carbonate and propylene carbonate are preferred, and ethylene carbonate is particularly preferred.

In the production method of the present invention, first, the components (A) and (B) are mixed at a ratio satisfying the above formula (5), and a heating reaction is carried out to carry out melt polymerization.

Here, when the use ratio of the glycol (B) is out of the range of the above formula (5), the esterification reaction becomes slow and the polymerizability decreases, which is not preferable. The use ratio of the glycol (B) preferably satisfies the following formula (5-1), and more preferably satisfies the following formula (5-2).

[0017]

(3) 1.1 ≦ b / a ≦ 2 (5-1) 1.2 ≦ b / a ≦ 2 (5-2)

For the melt polymerization, a known method conventionally used in the field of polyester can be used as it is. That is, as the reaction conditions, the reaction temperature is 2
The reaction time is about 40 to 320 ° C, preferably about 260 to 300 ° C, and the reaction time is about 1 to 24 hours, preferably about 2 to 20 hours. In the reaction, the pressurized state under an inert gas atmosphere is maintained for a while, and the aromatic dicarboxylic acid (A) is completely melted in the system. The pressure condition is 1 to 30 kg / cm ² , preferably ² kg / cm ² .
The range is from 10 kg / cm ^{2 to} 10 kg / cm ² . Thereafter, a deglycol reaction is carried out under normal pressure or reduced pressure, and the esterification rate is advanced to 80% or more. If the esterification rate is less than 80%, the subsequent reaction does not proceed, and a copolymerized polyester having a sufficient degree of polymerization cannot be obtained. This esterification ratio can be determined from the amount of carboxyl groups at the polymer terminals.

At the time of this polymerization reaction, the polymerization catalyst may be:
Although not particularly necessary, a known catalyst can be appropriately used to promote the reaction.

In the production method of the present invention, following the above reaction, the above aromatic dihydroxy compound (C), alkylene carbonate (D) and catalyst are added, and a ratio satisfying the above formulas (6) and (7) And perform a melt polymerization reaction.

Formula (6) shows the use ratio of the aromatic dihydroxy compound (C) to the aromatic dicarboxylic acid (A). The use ratio preferably satisfies the following formula (6-1). It is more preferable to satisfy the expression (6-2).

[0022]

## EQU4 ## 0.03a ≦ c ≦ 0.97a (6-1) 0.05a ≦ c ≦ 0.95a (6-2)

In the formula (7), when the use ratio of the alkylene carbonate (D) is less than 1.8 equivalents to the aromatic dihydroxy compound (C), the residual amount of unreacted phenolic OH increases. If the polymerizability decreases, and if it is more than 3 equivalents, unreacted alkylene carbonate needs to be distilled off, which is not preferable. The ratio of the alkylene carbonate (D) to the aromatic dihydroxy compound (C) preferably satisfies the following formula (7-1), and more preferably satisfies the following formula (7-2).

[0024]

1.9c + 2a (1-e / 100) ≦ d ≦ 2.7c + 2a (1-e / 100) (7-1) 2.0c + 2a (1-e / 100) ≦ d ≦ 2.5c + 2a (1 -E / 100) (7-2)

The catalyst used in the reaction promotes a transesterification reaction and an etherification reaction between the aromatic dihydroxy compound (C) and the alkylene carbonate (D), and examples thereof include the following compounds. Alkali metal compounds such as sodium carbonate, potassium carbonate, lithium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium hydroxide, potassium hydroxide, sodium methoxide, lithium acetate, sodium acetate, potassium acetate; magnesium hydroxide, calcium hydroxide , Magnesium carbonate, calcium acetate, alkaline earth metal compounds such as strontium carbonate; manganese compounds such as manganese acetate; tin compounds such as dibutyltin oxide, dibutyltin diacetate, stannous acetate; zinc compounds such as zinc acetate; Titanium compounds such as butyl titanate; antimony compounds such as antimony trioxide; germanium compounds such as germanium oxide;

The amount of these catalysts is not particularly limited,
The amount is about 0.005 to 0.5 mol% with respect to the total equivalent weight of the aromatic dicarboxylic acid (A). These catalysts may be used alone or in combination of two or more.

In this reaction, it is necessary to carry out the reaction until carbon dioxide gas is generated in an amount of 150 mol% or more based on the amount of the aromatic dihydroxy compound (C) used. The carbon dioxide gas generated here is generated by a reaction between the aromatic dihydroxy compound (C) and the alkylene carbonate (D), and a hydroxyalkyl ether of the aromatic dihydroxy compound (C) is generated by this reaction. Therefore, the progress of the etherification reaction can be checked by monitoring the amount of carbon dioxide gas generated. The amount of generated carbon dioxide can be easily measured by, for example, a gas flow meter, a gas flow integrator, or the like. If the generated amount is less than 150 mol% with respect to the amount of the aromatic dihydroxy compound (C), the etherification reaction is insufficient, and as a result, the residual amount of the low-reactive phenolic OH group increases, and the polymerization proceeds. There is a problem that the property is reduced. The amount of carbon dioxide generated is preferably at least 160 mol%, more preferably at least 170 mol%, particularly preferably at least 180 mol%, based on the amount of the aromatic dihydroxy compound (C) used.

As the reaction conditions for the melting reaction, the reaction temperature is generally 150 to 260 ° C., preferably 170 to 240 ° C.
And the reaction time is about 30 minutes to 8 hours, preferably about 1 to 6 hours. This reaction can be preferably carried out at normal pressure in a stream of an inert gas such as nitrogen or argon. However, after the generation of carbon dioxide gas has started, it is not necessary to introduce these inert gases forcibly. It is preferable to temporarily stop the introduction of the inert gas for measurement. In this case, it is preferable to introduce an inert gas after confirming the generation of a predetermined amount of carbon dioxide gas.

At the time of this reaction, the polyester oligomer comprising the aromatic dicarboxylic acid (A) and the aliphatic glycol (B) formed by the preceding reaction at the same time as the above-mentioned etherification reaction, and the aromatic dihydroxy compound ( The transesterification reaction of C) with the hydroxyalkyl ether proceeds. According to the method of the present invention, the distillation of excess glycol (B) is promoted by the generation of carbon dioxide gas, and the transesterification reaction proceeds rapidly. After the generation of carbon dioxide has ceased, the glycol removal reaction is allowed to proceed at normal pressure or reduced pressure to obtain the desired copolymerized polyester.

[0030]

According to the method for producing a copolymerized polyester of the present invention, an inexpensive aromatic dihydroxy compound can be used as a raw material for polymerization without using a hydroxyalkyl ether of an aromatic dihydroxy compound as in the prior art. . Therefore, not only can the raw material cost be reduced, but also various aromatic dihydroxy compounds, which have been difficult to synthesize and purify hydroxyalkyl etherified compounds, can be used as they are. Its industrial significance is extremely large, for example, a copolymerized polyester having a structure can be synthesized.

The copolyester of the present invention can be used for fibers, films, sheets, plastics, adhesives, binders,
Used as a coating resin. Particularly, it is suitable as a binder resin for toner.

[0032]

The present invention will be described in detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. In the examples,
“Parts” indicates parts by weight.

The reduced viscosity (ηsp / C) of the polymer was determined by using a mixed solvent of phenol / 1,1,2,2-tetrachloroethane (weight ratio: 6/4) and a polymer concentration of 1.2 g / d.
1, measured at a temperature of 35 ° C.

The thermal characteristics of the polymer were measured using a DSC under the condition of a heating rate of 20 ° C./min.

The esterification ratio was determined from the amount of carboxyl groups at the terminal of the polymer. The amount of terminal carboxyl groups was determined for sample 30.
mg was dissolved in 10 cc of benzyl alcohol and titrated with N / 50 NaOHaq using phenol red as an indicator.

Example 1 166 parts of terephthalic acid (10
0 mol%), 74.4 parts (120 mol%) of ethylene glycol and 0.015 part (0.4 mol%) of lithium acetate dihydrate.
015 mol%) into a reaction vessel having a distilling system via a stirrer and a rectification column. At room temperature, the reaction vessel is replaced with nitrogen gas, and then charged with 3 kg / cm ² G nitrogen gas. Start heating. The outflow of water starts as the internal temperature rises. After raising the internal temperature to 240 ° C., the mixture was heated and stirred for 3 hours.
At this point approximately 80 mol% of the theoretical amount of water had distilled off.
The mixture was further heated and stirred for 3 hours. After the outflow of water almost stopped, the pressure was gradually returned to normal pressure over 0.5 hours to obtain a polyester oligomer. The amount of terminal carboxyl groups of the obtained oligomer was 355 eq / 10 ⁶ g, and the esterification rate was 90%.

To the obtained reaction product, 103 parts (45 mol%) of 2,2-bis (4-hydroxyphenyl) propane, 102 parts (100 mol%) of propylene carbonate and 0.1 part of sodium carbonate were added, and nitrogen was added again. After purging with gas, the reaction vessel was heated to 200 ° C. under normal pressure. Internal temperature is 18
When the temperature reached 0 ° C., the introduction of nitrogen gas was stopped, and a gas flow meter equipped with an integrator was connected to the end of the reaction distilling system to measure the amount of carbon dioxide gas generated in the reaction system. After maintaining at a reaction temperature of 200 ° C. for 1 hour, the temperature was raised to 220 ° C. and the reaction was further performed for 1.5 hours. At this point,
Carbon dioxide was generated in a molar amount of 190% based on the charged amount of bis (4-hydroxyphenyl) propane. Further, 0.38 part of p-toluenesulfonic acid hydrate and 0.08 part of tetrabutyl titanate were added thereto, and the system was subjected to a deglycol-reaction in a nitrogen stream for about 5 hours while keeping the system at normal pressure. The resulting polymer was pale yellow and transparent, and ηsp / C0.
22, Tg 66 ° C. This polymer could be used as a binder resin for a toner.

Claims (1)

[Claims] 1. An amount of an aromatic dicarboxylic acid (A) represented by the following formula (1) satisfying the following formula (5) and an aliphatic glycol (B) represented by the following formula (2) are converted into (A) )
And then subjected to a heat reaction until the esterification ratio became 80% or more, and then an aromatic dihydroxy compound (C) represented by the following formula (3) and a 5-membered ring and / or 6-membered ring represented by the following formula (4) Cyclic alkylene carbonate (D)
Is added in such an amount that satisfies the following formulas (6) and (7), and is subjected to a melting reaction in the presence of a catalyst until carbon dioxide gas is generated in an amount of 150 mol% or more based on the amount of the aromatic dihydroxy compound (C) used. A method for producing a copolyester, comprising: Embedded image [In the formula (1), Ar ₁ represents an aromatic residue having 6 to 12 carbon atoms. In the formula (2), R ₁ represents alkylene having 2 to 6 carbon atoms. In the formula (3), Ar ₂
Aromatic having from 6 to 12 carbon atoms is acid residue or -Ar ₃ -X
—Ar ₃ — (where Ar ₃ is an aromatic residue having 6 to 12 carbon atoms, and X is —C (CH ₃ ) ₂ —, —O—, —CO
_{-, - SO 2 -, -} S- or a divalent residue of good 1 to 15 carbon atoms optionally containing heteroatoms. ). In the formula (4), R ₂ represents an alkylene having 2 to 5 carbon atoms in which a cyclic carbonate structure forms a 5- or 6-membered ring. 1 ≦ b / a ≦ 2 (5) 0.01a ≦ c ≦ 0.99a (6) 1.8c + 2a (1-e / 100) ≦ d ≦ 3.0c + 2a (1-e / 100) (7) [In formulas (5), (6) and (7), a, b, c
And d indicate the number of equivalents of the components A, B, C and D, respectively. e indicates the esterification rate (%) after the reaction between the component A and the component B. ]