JPS63314229A - Production of heat-resistant polymer - Google Patents

Abstract

PURPOSE:To produce a heat-resistant polymer excellent in radiation resistance, hot dimensional stability, etc., by reacting an organic diisocyanate with an organic polycarboxylic acid (anhydride) in the presence of a dissolved alkali metal fluoride catalyst. CONSTITUTION:A catalyst solution is obtained by dissolving an alkali metal fluoride (e.g., KF) as a catalyst in a solvent such as N-methyl-2-pyrrolidone or dimethylacetamide. An organic diisocyanate (e.g., 1,2-diisocyanatoethane) is reacted with an organic polycarboxylic acid (anhydride) (e.g., trimellitic anhydride) for 1-20hr at 20-250 deg.C and a molar ratio of 1:0.70-1.30 in the presence of 0.01-10mol.% said catalyst solution in an inert organic solvent in an inert gas atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing a heat-resistant polymer obtained from an organic diisocyanate and an organic polycarboxylic acid or an organic polycarboxylic acid anhydride.

[Conventional technology]

It is well known that heat-resistant polymers can be produced by reacting organic diisocyanates with organic polycarboxylic acids or organic polycarboxylic acid anhydrides; however, in general, fibers,
It is difficult to obtain polymers with high molecular weight that can be processed into films, molded products, etc. and have sufficient physical properties.
For this reason, adhesives, adhesives, etc. were mostly used. In addition, when the organic diisocyanate used in the reaction reacts,
In particular, various side reactions occur at high temperatures, which often results in gelation during the reaction, and side-reactants are mixed into the polymer, causing problems such as deterioration of the polymer's heat resistance and various physical properties. was there. For this reason, various catalysts have been developed for the above reaction system. For example, (1) Method using metal alkoxide or metal phenoxide: U-S-P, 4.00
1.186.4.061.622 and 4°061.62
3, (How to use 21 Lackumate: U.S.-
P, 4.021.412.4.094.864 and 4
．． 094.866, (3) Method using cyclic phosphorus oxide: U.S.-P, 4.156.065, and (4) Method using alkali metal salt of polyhydric carboxylic acid: JP-A-57-151615 , (5) Method using alkali metal carbonate or hydrogen carbonate 2 JP-A-58-18
629, (6) Method using alkali metal hydroxide:
Examples include JP-A-58-67723. However, even when the above catalysts are used, they often gel due to side reactions of organic diisocyanates or form polyisocyanates, making it difficult to obtain linear, high-molecular-weight polymers, making it difficult to obtain polymers with good physical properties. There were problems such as not being able to obtain

[Problem that the invention seeks to solve]

An object of the present invention is to provide a method for producing a linear high molecular weight polymer that does not undergo gelation during the reaction and suppresses side reactions caused by organic diisocyanates.

[Means for solving problems]

The present inventors investigated a method for producing a heat-resistant polymer by reacting such an organic diisocyanate with an organic polycarboxylic acid or an organic polycarboxylic acid anhydride, and as a result, the present invention was completed. It is.

That is, the present invention provides a method for producing a heat-resistant polymer by reacting an organic diisocyanate with one or more compounds selected from the group consisting of organic polycarboxylic acids or organic polycarboxylic acid anhydrides, in which an alkali is used as a catalyst. This is a method for producing a heat-resistant polymer, characterized in that metal fluorides are used in a dissolved state.

As the organic diisocyanate that can be used in the present invention, -
1) ffl All known organic polyvalent isocyanates can be used, but in particular those described in JP-A-57-151615, such as 1,2-diisocyanate ethane,
Cyclohexane-1,4-diisocyanate, 4.4°
-methylene bis(cyclohexyl isocyanate),
m-xylene diisocyanate phenylene-1,4-
Diisocyanate, phenylene-1,3-diisocyanate, tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate, diphenylmethane-41
4'-diisocyanate, diphenyl ether-4,4
'-diisocyanate, 1,5-naphthalene diisocyanate, and the like.

In addition, the following are examples of organic polycarboxylic acids or organic polycarboxylic acid anhydrides that can be used in the present invention.
For example, as an organic polycarboxylic acid, JP-A-57-179
No. 223, for example, dicarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, superric acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, and hexahydroterephthalic acid.・Diphenylsulfone-4,4°-dicarboxylic acid, biphenyl-4,4°-dicarboxylic acid, thiophene-2,5-dicarboxylic acid, pyridine-2,6-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, 4 .4'-
diphenylmethane-bis-trimeric imide a,
4.4'-diphenyl ether-bis-trimellitic imide acid and the like. In addition, tricarboxylic acids include pukun-1,2,4-1-dicarboxylic acid, cyclohexane-1,
1,2,3-tricarboxylic acid, cyclobencundenyl-3,4,4'-)dicarboxylic acid, cyclobentadienyl-1,2,4-)dicarboxylic acid, benzene-1,2
, 4-tricarboxylic acid, naphthalene-1,4,5-)dicarboxylic acid, biphenyl-3,4,4°-tricarboxylic acid, diphenylsulfone-3,4,3'-tricarboxylic acid, diphenyl ether-3,4,3 '-tricarboxylic acid, benzophenone-3,4,4°-tricarboxylic acid, and the like. Examples of tetracarboxylic acids include butane-1,2,3,4-tetracarboxylic acid, pentane-1,
2,4,5-tetracarboxylic acid, cyclohexane 1,2
, 3.4-tetracarboxylic acid, benzene-1,2,4,
5-tetracarboxylic acid, naphthalene 2,3,6,7-tetracarboxylic acid, biphenyl-3,3°, 4,4゛ -
Tetracarboxylic acid, benzophenone-3,3", 4.4
“-Tetracarboxylic acid, diphenol-1-noether-3.
3',4,4'-tetracarboxylic acid, diphenylsulfone(3,4-dicarboxyphenyl)pronokone, furan-2.3.4.5-tetracarboxylic acid, pyridine-2
, 3,5.6-tetracarboxylic acid and the like.

The organic polycarboxylic acid anhydride is, for example, an acid anhydride derived from LL'tricarboxylic acid, which in this case contains one carboxyl group and one acid anhydride group in the molecule, and further contains a tetracarboxylic acid anhydride. In this case, there are those containing two acid anhydride groups in the molecule, and those containing one acid anhydride group and two carboxyl groups, and the following are examples: ．． Examples of organic polycarboxylic acid anhydrides include trimellidic anhydride, benzene-1,
2.3-tricarboxylic anhydride, butane-1.2,3.
4=tetracarboxylic dianhydride, pyromellitic dianhydride, diphenyl-3.3',4.4°-tetracarboxylic dianhydride, naphthalene-2.3.6.7-tetracarboxylic dianhydride , naphthalene-1,4,5,8-tetracarboxylic dianhydride, diphenyl ether-3,3゛,
4,4°-tetracarboxylic dianhydride, diphenylsulfone-3,3″.4.4°-tetracarboxylic dianhydride, diphenylketone 3.3°,4.4″-tetracarboxylic dianhydride , 2,2-bis(3.4-dicarboxyphenyl)propane dianhydride, furan-2.3,4.
5-tetracarboxylic dianhydride, pyridine-2.3,5
, 6-tetracarboxylic dianhydride, and the like.

The heat-resistant polymer obtained from organic diisocyanate and organic polycarboxylic acid or organic polycarboxylic acid anhydride has (1
) Organic diisocyanate and organic polycarboxylic acid, (2)
They can be roughly divided into organic diisocyanates, organic polycarboxylic acids and organic polycarboxylic acid anhydrides, and (3) organic diisocyanates and organic polycarboxylic anhydrides, but all are useful as heat-resistant polymers, and (1) In the case of (2), the skeleton of the polymer produced is formed from an amide group, and in the case of (3), it is formed from an imide group. Group I is a compound whose main component is an alkali metal fluoride, and includes (1) an alkali metal fluoride, (2) a salt of an alkali metal fluoride and a polyhydric carboxylic acid, and (3) an alkali metal fluoride. and a crown compound, (4) an alkali metal fluoride carrier, etc. Examples of the alkali metal fluoride (1) include lithium fluoride, sodium fluoride, potassium fluoride, cesium fluoride, and rubidium fluoride, with potassium fluoride and cesium fluoride being particularly preferred. (2) The salt of an alkali metal fluoride and a polyvalent carboxylic acid is preferably a salt of the above-mentioned alkali metal fluoride and a raw material polyvalent carboxylic acid used in producing the heat-resistant polymer.

(3) For the salt of an alkali metal fluoride and a crown compound, the above alkali metal fluoride and dibenzo-14-crown-
Preferred are salts such as 4,15-crown-5, dicyclohexyl-18-crown-6, dibenzo-18-crown-6, and dicyclohexyl-24-crown-8. (4
) The alkali metal fluoride carrier preferably uses activated carbon alumina, diatomaceous earth, zeolite, silica gel, or the like.

In addition, using alkali metal fluorides as a catalyst in a dissolved state means that (Tl) the alkali metal fluorides are dissolved in the solvent, and (2) the alkali metal fluorides are dissolved during polymerization. means.

When producing heat-resistant polymers using alkali metal fluorides dissolved in a solvent as a catalyst, the alkali metal fluorides may precipitate during polymerization;
This does not impede the effects of the present invention. Conversely, even if the alkali metal fluorides are not dissolved before polymerization, as long as they are dissolved during polymerization, the effects of the present invention can be fully exhibited.

As a method for dissolving alkali metal fluorides, (1
) Dissolve an alkali metal fluoride in a solvent such as N-methyl-2-pyrrolidone, dimethylacetamide, or 1,3-dimethyl-2-imidazolidinone at room temperature or with heating. (2) After dissolving the organic polycarboxylic acid in the above solvent, the alkali metal fluoride is dissolved. etc., but other methods are of course possible.

By using the alkali metal fluorides in a dissolved state, there is no need for operations such as filtration when spinning the polymerization solution as it is, which is industrially advantageous.

The reaction according to the method of the present invention is carried out under substantially anhydrous conditions, in which a mixture of an organic diisocyanate and an organic polycarboxylic acid or an organic polycarboxylic acid anhydride and an alkali metal fluoride is reacted in an inert organic solvent with an inert gas, e.g. Heating is carried out under a nitrogen atmosphere at a temperature of 20°C to 250°C, preferably 100°C to 200°C, for 1 to 20 hours. The molar ratio of organic polycarboxylic acid or organic polycarboxylic acid anhydride to organic diisocyanate used in the reaction is 1:0.70 to i:i,
It is used in the range of ao, but especially t:o, ss~1). 1
It is preferable to use the alkali metal fluoride in the range of 0. Outside this range, a heat-resistant polymer with a high molecular weight cannot be obtained. 0 for anhydrous.
The content is preferably 0.01 to 10 mol%, particularly preferably 0.1 to 5 mol%. If the amount is less than this range, it will be difficult to obtain a high molecular weight polymer, and if the amount is more than this range, the heat resistance of the polymer will decrease due to the catalyst residue remaining in the produced polymer, resulting in a problem of quality deterioration. . The raw material isocyanate, carboxylic acid or acid anhydride, and dissolved alkali metal fluoride may be added to the reaction system at the same time or in any order, but usually they are added at the same time at room temperature. Alternatively, it is preferable to use a solvent and supply the raw materials into the solvent. Depending on the case, one of the raw materials, isocyanate and carboxylic acid or acid anhydride, preferably isocyanate, may be added and reacted continuously at a predetermined reaction temperature. Further, the amount of the solvent to be used can be appropriately selected depending on the performance of the final polymer and the reaction temperature. Generally, it is preferable to select conditions that do not interfere with stirring due to thickening during polymerization.

Examples of aqueous solvents used in the present invention include N, N-
Chain or cyclic amides or phosphorylamides such as dimethylacetamide, N,N-dimethylformamide, N-methylpyrrolidone, T-butyrolactone, hexamethylphosphoric triamide, or sulfoxides or sulfones such as dimethylsulfoxide and diphenylsulfone. ureas such as tetramethylurea, cyclic ureas such as dimethylethylene urea, or benzene, toluene, xylene, decalin, cyclohexane,
Heptane, hexane, pentane, methylene chloride, chlorobenzene, dichlorobenzene, tetrahydrofuran, etc. are used.

After completion of polymerization, in order to separate the polymer as a solid, the reaction solution is poured into a non-solvent for the polymer to precipitate the polymer. The precipitated polymer is also thoroughly washed with the same non-solvent to remove remaining catalyst and other impurities. After washing, the polymer is dried at room temperature or high temperature, and in some cases under reduced pressure. The polymer thus obtained can be melt-molded, or in some cases redissolved in a solvent to be used as a face, adhesive, or used in the production of cast films and fibers. Further, the polymerization solution can be used as it is as a dope for spinning.

〔Example〕

The method of the present invention will be explained below using Examples, but the present invention is not limited by these.

[Example I]

28.95 g (0,1743 mol) of terephthalic acid and 15.07 g (0,0907 mol) of isophthalic acid were charged into a 5001) 1 separable flask equipped with a stirrer, thermometer, condenser, dropping funnel, and nitrogen introduction tube. Potassium fluoride 0.021g (3,6X 10-4 mol)
was dissolved in 50 ml of N-methyl-2-pyrrolidone and 412 ml of the solvent tetramethylene sulfone were added, the mixture was heated to 200 t, and 35.81 g (0,2056 mol) of tolylene-2,4-diisocyanate was added for 2 hours. The mixture was added dropwise and stirred for an additional 2 hours, followed by cooling to room temperature. During cooling, the polymer became almost slurry-like at room temperature. Thoroughly wash with a large amount of methanol and heat at 150℃ for 3
Dry under reduced pressure for an hour. Logarithmic viscosity of the obtained polymer (polymer 0.1 g/100 cc using concentrated sulfuric acid as a solvent, 3
The viscosity (ηinh) at 0°C was 2.8. From the IR spectrum of the polymer, 1,660 cm-1,1
, 530 cm -1 amide absorption was observed. A 10% by weight dope of this polymer dissolved in dimethylacetamide was cast onto a glass plate, dried under reduced pressure at 50°C for 1 hour, peeled off the film from the glass plate, fixed to a frame, and dried under reduced pressure at 280°C for 3 hours. A transparent, opalescent, tough film was obtained. The tensile strength of this film is 132
The elongation was 15% at 0Kg/c+w''.The Tg of the film was 285℃ (TMA method),
The 5% weight loss temperature determined from the /win sample (101 mg) was 415°C.

This film was left in the air at 280° C., and the time required for the tensile strength to decrease by half was determined to be 480 hours.

[Example 2] Polymerization was carried out in the same manner as in Example 1, using a solution of cesium fluoride in N-methyl-2-pyrrolidone instead of potassium fluoride. Post-treatment was performed in the same manner as in Example 1 to obtain a milky white polymer powder. The logarithmic viscosity of this polymer was 2.7 and the film Tg was 265°C.

Furthermore, the time required for the film to reduce by half in air at 280°C was found to be 500 hours.

[Comparative Example 1] Polymerization was carried out in the same manner as in Example 1, except that 0.021 g (3,6 x 10 -4 mol) of potassium fluoride was used as it was without dissolving it in N-methyl-2-pyrrolidone, and a film was prepared. was created. The logarithmic viscosity of this polymer was 2.7, and the tensile strength of the film was 1) 14% elongation at 90 kg/cm.Furthermore, the time required for the tensile strength of the film to decrease by half in air at 280°C was determined. It was 390 hours.

(Comparative Example 2) Polymerization was carried out in the same manner as in Examples 1 and 2 using sodium methoxide instead of the dissolved fluoride compound as a catalyst.

A mixture of 27.96 g (0,1683 mol) of terephthalic acid, 4:93 g (0,0297 mol) of isophthalic acid, 0.0980 g (0,0018 mol) of sodium methoxide and anhydrous sulfolane 41O layer 1 was maintained at 200 °C. , tolylene-2,4-diisocyanate at this temperature) 3
4.62 g (0.1988 mol) was added dropwise over 2 hours. After continuing stirring for an additional 2 hours, the mixture was cooled to room temperature and post-treated in the same manner as in Example 1 to obtain a polyamide. The obtained polymer had a logarithmic viscosity of 1.1. Further, the tg of the cast film made in the same manner as in Example 1 was 278°C, the 5% by weight tjIi temperature determined from a thermobalance was 386°C, the tensile strength was 935 g/2, and the elongation was 5%. Furthermore, the time required for the tensile strength of the film to decrease by half in air at 280°C was determined to be 200 hours.

These results are considerably inferior to those of the polyamide obtained in Example 1.

[Example 3] Using the same apparatus as in Example 1, polyamideimide was polycondensed. Trimellitic anhydride 20.05g (0
, 1044 mol), dibenzo-18-crown-62,
52g (7x10-3 mol) and potassium fluoride 0.030
A solution of a salt consisting of Jl (5,2X 10-4 mol) dissolved in N-methyl-2 to pyrrolidone 100s+1 and N
, N'-dimethyl-ethylene urea 3001 was charged,
The mixture was heated to 200° C. with stirring under nitrogen. The mixture was maintained at this temperature and 19.86 g (0,0788 mol) of diphenylmethane-4,4'-diisocyanate, tolylene-2,4-di'7, t-t4
．． A solution of 577 g (0,02628 mol) dissolved in N,N'-dimethylethylene urea 501 was added dropwise over 4 hours. After further reaction for 2 hours, the mixture was cooled to room temperature.

This product was poured into a large amount of methanol to precipitate the polymer, filtered, thoroughly washed with a large amount of methanol, and dried under reduced pressure at 150'C for 3 hours. The logarithmic viscosity of the obtained polymer was 1.21. The IR spectrum of this polymer is < 1770 cm based on imide groups.
< 1660 cm based on absorption at 20 cm and amide group
Absorption of −1,1530 cm −1 was observed.

A solution of this polymer in N-methylpyrrolidone (
A cast film made from 10% by weight) in the same manner as in Example 1 was a strong film with pale yellow edges, tensile strength 1) 60Kg/c+m'' and elongation 29%.
, was 256°C. The 5% weight loss temperature of this polymer was 458°C as measured by thermobalance.

Further, the time required for the tensile strength of this film to decrease by half at 280°C in air was determined to be 700 hours.

[Comparative Example 3] Polyamideimide was polymerized in the same manner as in Example 3, except that the salt consisting of dibenzo-18-crown-6 and potassium fluoride was used as it was without being dissolved in N-methyl-2-pyrrolidone. I got the film.

The logarithmic viscosity of the obtained polymer was 1.15.

Tensile strength of film 1) 40Kg/cm”, elongation 26
%, and the time required for this film to reduce its tensile strength by half at 280°C in air was 660 hours.

[Example 4] Polyimide was polymerized using the same apparatus as in Example 1. Benzophenone-3,3°,4,4'-f tracarboxylic dianhydride 25.50 g (0,0792 mol)
, 0.0077 g (5,1 x 10-4 mol) of cesium fluoride dissolved in N-methyl-2-pyrrolidone (301), and 50 m of N,N'-dimethyl-ethylene urea.
1 was charged, the mixture was maintained at 200°C, and 13.04 g (0
, 0517 mol) and tolylene-2,6-diisocyanate (4.85 g (0,0279 mol)) dissolved in 50 ml of N,N'-dimethylethylene urea were reacted dropwise over 2 hours. After continuing the reaction for an additional 2 hours, the mixture was cooled to room temperature. A portion of this polymerization solution was poured into a large amount of methanol to coagulate the polymer, and after thorough washing, 1
It was dried under reduced pressure at 50°C for 3 hours to obtain a pale yellow powder. The logarithmic viscosity of this polyimide was 1.18. Further, a portion of this polymerization liquid was cast onto a glass plate and dried in the same manner as in Example 1 to obtain a light brown transparent tough film. This film has a tensile strength of 1) 60Kg/cm” and an elongation of 4
It was 8%.

Further, the time required for this film to reduce its tensile strength by half at 320° C. in air was determined to be 850 hours.

[Comparative Example 4] Polyimide was polymerized in the same manner as in Example 4 except that cesium fluoride was used as it was without being dissolved in N-methyl-2-pyrrolidone, and the obtained polymer had a logarithmic viscosity of 1. It was 09.

Tensile strength of film 1) 20Kg/cm”, elongation 45
%, and the time required for this film to reduce its tensile strength by half at 320°C in air was 650 hours.

[Effects of the present invention]

In addition to heat resistance, the polymer according to the present invention has excellent heat insulation properties, radiation resistance, thermal dimensional stability, mechanical properties, electrical properties, chemical resistance, and flame retardancy, so it can be used as a variety of industrial materials, Highly functional industrial materials such as protective materials, composite materials, reinforcing materials, and electrical insulation materials, as well as molded products, films, paper, fibers, and festivals in the electrical, electronic, automobile, vehicle, and aircraft industries, as well as the clothing and interior fields. , can be widely used in adhesives, etc.

Claims (5)

[Claims] (1) In a method for producing a heat-resistant polymer by reacting an organic diisocyanate with one or more compounds selected from the group consisting of an organic polycarboxylic acid or an organic polycarboxylic acid anhydride, an alkali metal fluoride is used as a catalyst. A method for producing a heat-resistant polymer, which comprises using a compound in a dissolved state. (2) The method according to claim 1, wherein a heat-resistant polymer is produced by reacting an organic diisocyanate and an organic dicarboxylic acid. (3) The method according to claim 1, wherein the heat-resistant polymer is produced by reacting an organic diisocyanate with a compound selected from the group consisting of organic tricarboxylic acids or tricarboxylic anhydrides. (4) The method according to claim 1, wherein the heat-resistant polymer is produced by reacting an organic diisocyanate with a compound selected from the group consisting of organic tetracarboxylic acids or tetracarboxylic dianhydrides. (5) The method according to claim 1, wherein the alkali metal fluoride is potassium fluoride or cesium fluoride.