JPH0417211B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a novel crystalline poly(ether thioether aromatic ketone) and a method for producing the same. More specifically, the present invention has a chemical structure in which phenylene groups are linked via an ether group, a thioether group, and a ketone group, and has excellent heat resistance, solvent resistance, flame retardancy, mechanical properties, etc. The present invention relates to a new crystalline polymer and a method for industrially producing the same. Prior Art Until now, as a polymer compound having a structure in which phenylene groups are connected via an ether group and a ketone group, the structural formula is or structural formula These materials are attracting attention as molding materials because they have excellent heat resistance, molding stability, and mechanical strength. However, these polymer compounds have problems in production, such as the need to use raw materials that are difficult to obtain, and the need to use a solvent that is solid at room temperature, which poses difficulties in terms of equipment and operation. A manufacturing method suitable for this is not yet known. For example, the high molecular weight polyether aromatic ketone represented by the above formula () is produced by the condensation reaction of dihalobenzophenone and hydroquinone, but in order to have practical physical properties, it is necessary to It became necessary to use difluorobenzophenone as the benzophenone (Japanese Unexamined Patent Application Publication No. 1989-1999).
90296), the cost of raw materials inevitably increases. In addition, in order to obtain crystalline, high-molecular-weight polyether aromatic ketones, it is necessary to use a compound that is solid at room temperature, such as diphenyl sulfone (melting point 128-129°C), as a polymerization solvent (Japanese Patent Publication No. 56
-2091 Publication, JP-A-54-90296, Tokuko Sho
57-22938), production methods using such solvents require special equipment and are complicated to separate the product, recover the solvent, and purify, making them difficult to implement industrially. is inappropriate. In addition, a method using N-alkylcaprolactam as a liquid polymerization solvent has also been proposed (Japanese Patent Publication No. 51-8439
This solvent is unstable under high-temperature alkaline conditions, and when used in high-temperature polymerization in alkali metal carbonates, it separates and turns black, resulting in a disadvantage that the resulting polymer is colored. . On the other hand, a method for producing poly(ether thioether) from an alkali metal salt of hydroxythiophenol and an aromatic dihalide is known (Japanese Patent Publication No. 49-44954), but the polymer obtained by this method has no ether bonds. Since it has an internal structure in which the and thioether bonds are arranged irregularly, it is amorphous and is not necessarily satisfactory in terms of heat resistance, solvent resistance, mechanical properties, etc. We also proposed a method for producing polyether or polythioether from a compound having two -XH groups (where X is an oxygen atom or a sulfur atom) and a dihalobenzenoid compound in the presence of potassium carbonate. (Special Publication No. 47-21595). However, in this method, the polymerization temperature is low and it is not possible to obtain a crystalline polymer as in the case described above. Thus, until now, there has been no known method for producing a crystalline polymer having a structure in which aromatic rings are linked through ether groups and ketone groups from readily available raw materials and by simple means. Ta. Problems to be Solved by the Invention The object of the present invention is to provide a novel crystalline material that can be produced using readily available raw materials and by simple means, and that has excellent heat resistance, solvent resistance, and mechanical properties. Poly(ether thioether aromatic ketone). Means for Solving the Problems As a result of intensive research, the present inventors found that 4,4'-dihaloterephthalophenone and 4,4'-dihaloterephthalophenone, which had previously been thought to be the only available amorphous polymer, could be obtained as a raw material. −
It was discovered that by polymerizing hydroxythiophenol under specific conditions, a crystalline polymer having a specific structure could be obtained unexpectedly, and the above object could be achieved.Based on this knowledge, the present invention was developed. It was completed. That is, the present invention provides the formula The structural unit shown by and the formula A crystalline poly(ether thioether aromatic ketone) having a linear polymer structure in which structural units shown in or using an aromatic sulfone in the presence of at least one selected from carbonates and bicarbonates of alkali metals at a temperature within the range of 200 to 400 °C,
The present invention provides a method for producing a polycondensate by polycondensing substantially equimolar amounts of 4-hydroxythiophenol and 4,4'-dihaloterephthalophenone. The raw material monomers used in the present invention are 4-hydroxythiophenol and the general formula (X ¹ and X ² in the formula represent halogen atoms,
They may be the same or different)
It is 4,4'-dihaloterephthalophenone represented by Specific examples of 4,4'-dihaloterephthalophenones include 4,4'-dichloroterephthalophenones, 4,4'-difluoroterephthalophenones, and 4,4'-dichloroterephthalophenones.
-chloro-4'-fluoroterephthalophenone and the like. These monomers may be used alone or in combination of two or more. Thus, in the present invention, it is not necessary to use a fluorine compound that is difficult to obtain as a raw material, and even if an easily available compound in which both X ¹ and X ² are chlorine atoms can be used. A high-molecular weight polymer can be obtained in almost the same polymerization time as when using this method. In the present invention, the aliphatic sulfone or aromatic sulfone used as a solvent has the general formula R ¹ −SO ₂ −R ² ...() (wherein R ¹ and R ² are aliphatic residues or aromatic residues. and they may be the same or different, and R ¹ and R ² may be bonded directly through a carbon-carbon bond or via an oxygen atom), and specific examples include , dimethylsulfone, diethylsulfone, sulfolane, diphenylsulfone, ditolylsulfone, methylphenylsulfone, dibenzothiophene oxide, phenoxatine dioxide, 4-phenylsulfonylbiphenyl, and the like. Among these, sulfolane and aromatic sulfone are particularly suitable as they are stable even in high temperature polymerization. As described above, in the present invention, even if a solvent such as sulfolane (melting point 27 to 28°C), which is liquid at room temperature, is used, a crystalline polyether thioether aromatic ketone with a sufficiently high molecular weight can be obtained. Extremely advantageous. Examples of the alkali metal carbonates and alkali metal bicarbonates used in the present invention include sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, rubidium hydrogen carbonate, and cesium hydrogen carbonate. may be used alone or in combination of two or more. Also, among these,
Particularly suitable are sodium carbonate, potassium carbonate, sodium hydrogen carbonate, and potassium hydrogen carbonate. Next, a preferred embodiment of the production method of the present invention will be described. First, in an aliphatic sulfone or aromatic sulfone solvent, a required amount of an alkali metal carbonate and an alkali metal bicarbonate are added. At least one alkali metal salt is added, 4-hydroxythiophenol and 4,4'-dihaloterephthalophenone. At this time, the solvent is usually 10 parts by weight per 100 parts by weight of 4-hydroxythiophenol and 4,4'-dihaloterephthalophenone.
It is used in the range of ~1000 parts by weight. The alkali metal salt is used in such a proportion that the amount of alkali metal atoms is from 0.3 to 2 gram atoms, preferably from 0.5 to 1.2 gram atoms, per 1/2 mole of 4-hydroxythiophenol. If the alkali metal salt is used in excess, the reaction becomes too vigorous, causing harmful side reactions, and is also disadvantageous in terms of cost, so it is desirable to use as little amount as possible. However, when the amount of alkali metal atoms is less than 0.3 gram atoms, it is necessary to lengthen the polymerization time, and it becomes difficult to obtain a polymer with a desired high molecular weight. The alkali metal salt is preferably anhydrous, but
In the case of a hydrated salt, it can be used by distilling off water together with the azeotropic solvent from the polymerization reaction system. In addition, 4-hydroxythiophenol and 4,
The ratio of the 4'-dihaloterephthalophenone used must be substantially equimolar, and the latter is selected in the range of 0.95 to 1.05 mol per 1 mol of the former, and if it deviates from this range, it will be too high. It becomes difficult to obtain a molecular weight polymer. In order to make the polymer terminal a stable aromatic dihalide unit, 1.00 to 1.05 mol of 4,
Particular preference is given to using 4'-dihaloterephthalofenones. Next, the mixture of the solvent, alkali metal salt, and monomer is heated to 200-400°C, preferably under an inert gas atmosphere such as nitrogen or argon.
The polymerization reaction is carried out at a temperature range of 250-350°C. If this temperature is less than 200°C, the polymer will precipitate during polymerization and a high molecular weight polymer will not be obtained, while if it exceeds 400°C, the resulting polymer will deteriorate and become seriously discolored. Further, a rapid temperature rise is undesirable because it causes side reactions and causes coloring and gelation of the polymer. Therefore, it is necessary to raise the temperature stepwise or gradually so that the temperature of the polymerization system is kept as uniform as possible. In order to obtain a high molecular weight polymer with an intrinsic viscosity of 0.4 to 1.8, it is necessary that the polymerization temperature is ultimately 200° C. or higher, but it is advantageous to carry out the prepolymerization at a temperature lower than that. In addition, it is preferable to remove water generated during polymerization to the outside of the system, but methods for removing it include simply replacing the gas phase of the polymerization system with a dry inert gas, or A method of introducing a solvent into the system and distilling it out of the system together with the solvent is used. The polymerization reaction is carried out using a suitable terminal capping agent, such as a monofunctional or polyfunctional halide, specifically methyl chloride, tert-butyl chloride, 4,4'-dichlorodiphenyl sulfone, 4-4'-difluorobenzophene. Non, 4,4′-difluoroterephthalophenone,
It is possible to terminate the reaction by adding 4-fluorobenzophenone or the like to the reaction system at the above-mentioned polymerization temperature. Polymers having groups can be obtained. The polymer of the present invention obtained in this way has the structural unit ()

[Formula] and structure component unit ()

[Formula] are alternately connected. These structural units have the formula The structural unit corresponding to and the formula However, the polymer compound of the present invention may contain either one of these structural units, or may contain both randomly or regularly. Good too. Normally, if there is no particular control, there is no regularity in the connection format, and it is thought that the structure will be random. Furthermore, since mercapto groups are much more reactive than hydroxyl groups, if they are prepolymerized at a low temperature and then polymerized at a high temperature, the above formula ()
The structural unit in the connected form represented by
When 0.5 mol of 4,4'-dihaloterephthalophenone is reacted, a structural unit in the connected form represented by () above is preferentially produced. In this way, polymers with various regularities and irregularities can be produced even by combining the same monomers, depending on the polymerization temperature and the method of adding monomers. Among these, those with relatively high regularity and high crystallinity are desirable. Polymers produced in this way containing structural units with different linkage types in various proportions have different crystal melting points (Tm), glass transition temperatures (Tg), and crystallization speeds, so they differ depending on the application. It is possible to select an appropriate manufacturing method. Furthermore, the intrinsic viscosity of the polymer of the present invention is 0.40.4 to 1.8.
It is necessary that Polymers with an intrinsic viscosity of less than 0.4 are brittle and unsuitable for use as films or injection molded products. Effects of the Invention Compared to the conventional production of polyether aromatic ketones, the polymer compound of the present invention can be used at a lower cost as a dihaloaromatic compound as one component of the monomer, and can be polymerized. As a solvent, it is possible to use a solvent that is liquid at room temperature, such as sulfolane, which is easy to separate, recover, purify, etc., so it can be produced industrially advantageously. Depending on the type of linkage with (), it is possible to create polymers with various regularities and randomness, so depending on the application, the crystal melting point,
It has the advantage of being able to provide polymers with different glass transition temperatures, crystallization rates, etc. Furthermore, the poly(ether thioether aromatic ketone) of the present invention is a thermoplastic polymer with a high melting point, high molecular weight, and crystallinity, and has excellent mechanical properties in addition to excellent heat resistance and flame retardance. has and also
It hardly dissolves in solvents other than concentrated sulfuric acid at room temperature, and exhibits extremely excellent solvent resistance. Furthermore, compared to commercially available polyetheretherketone, it has better melt flowability and excellent moldability. Therefore, the crystalline poly(ether thioether aromatic ketone) of the present invention is suitable as a molding material used under severe conditions at high temperatures. This polymer can be used in any desired shape, such as molded products, coatings, films, fibers, etc., and can be mixed with various engineering plastics, heat-resistant resins, glass fibers, carbon fibers, inorganic materials, etc., to form alloys. It can also be used as a composite. Examples Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way. The polymer of the present invention is only slightly soluble in concentrated sulfuric acid and is insoluble in general organic solvents, so it is difficult to determine its average molecular weight. Therefore, the intrinsic viscosity is a measure of molecular weight. Moreover, the physical properties of the polymer were measured as follows. (1) Intrinsic viscosity Using concentrated sulfuric acid with a density of 1.84 g/cm ³ , a solution of 100 cm ³
A solution containing 0.1 g of polymer per solution and a solution containing 0.5 g of polymer ^per 100 cm of solution were prepared, and their viscosity was measured at 25°C, and the formula: Intrinsic viscosity = {(η _rel −1) / C} _c → _p [However, η _rel is relative viscosity, C is concentration (g/100
ml), and C→O means extrapolating the value of (η _rel −1)/C to the point where the concentration C is O. (2) Crystal melting point (Tm), glass transition temperature (Tg) Temperature increase rate 10℃/
Measured at min. (3) Crystallinity Determined from wide-angle X-ray diffraction and crystal melting point (Tm). Example 1 A separable four-necked flask equipped with a stirrer, a nitrogen inlet tube, and a condenser was purged with nitrogen, and then 14.20 g of 4,4'-dichloroterephthalophenone was added to it.
g (0.040 mol), 4-hydroxythiophenol
5.04g (0.040mol) Anhydrous potassium carbonate 5.52g
(0.040 mol), 40 ml of sulfolane, and 10 ml of toluene were added, and heating was started under a nitrogen atmosphere. After maintaining the temperature at which the toluene refluxed for 1 hour, the produced water was removed azeotropically with the toluene. Then 1 at 150℃
After holding at 180°C for 1 hour and 220°C for 1 hour, the temperature was raised to 260°C and held at that temperature for 3 hours, and the reaction solution became a pale yellowish white viscous liquid. Next, methyl chloride was bubbled in at this temperature for 20 minutes, then cooled and water was added. The resulting solid was crushed and washed twice with hot acetone and twice with warm water.
After another wash with acetone, a white solid of 16.1
I got g. This polymer consists of methylene chloride, chloroform,
It did not dissolve in solvents such as N,N-dimethylformamide, sulfolane, dimethyl sulfoxide, hexamethylphosphoric triamide, hexane, and toluene at room temperature. The X-ray diffraction chart and IR analysis chart of the obtained polymer are shown in FIGS. 1 and 2, respectively. Note that the powder obtained by polymerization was used as it was for X-ray diffraction and IR analysis. The results of elemental analysis of the polymer were as follows: C H O S measured value 76.5% 4.0% 11.6% 7.7% theoretical value 76.46〃 3.94〃 11.75〃 7.85〃. Further, this product had crystallinity, an intrinsic viscosity of 0.83, a Tm of 340°C, and a Tg of 150°C. The film obtained by pressing this polymer at 360°C for 5 minutes is extremely durable against repeated bending, and the tensile strength of this film is
The weight was 920 Kg/cm ² and the elongation at break was 80% (measurement method ASTMD882). Example 2 The same apparatus as in Example 1 was used, and 4,
4′-difluoroterephthalophenone 12.88g (0.040
mole) 4-hydroxythiophenol 5.04g
(0.040 mol), 4.42 g (0.032 mol) of anhydrous potassium carbonate, and 40 g of diphenysulfone were added, and heating was started under a nitrogen atmosphere. 1 hour at 150℃, 1 hour at 180℃
After holding at 250°C for an hour, the temperature was raised to 310°C and held at this temperature for 3 hours. Next, after cooling and pulverizing, it was washed twice with hot acetone and twice with warm water.
Further washing once with acetone gave a solid with 95% yield. This product has an intrinsic viscosity of 0.87, Tm342℃, Tg154
℃ and had crystallinity. Example 3 The same apparatus as in Example 1 was used, and 4,
4'-difluoroterephthalophenone 7.10g (0.020mol) 4-hydroxythiophenol 5.04g
(0.040 mol), 2.76 g (0.020 mol) of anhydrous potassium carbonate, and 40 g of diphenyl sulfone were added, and heating was started under a nitrogen atmosphere. After being held at 150°C for 1 hour and at 220°C for 1 hour, it was allowed to cool to room temperature. Next, 7.10 g of 4,4'-dichloroterephthalophenone
(0.020 mol), 2.77 g (0.020 mol) of anhydrous potassium carbonate were added, heated again, and held at 150°C for 1 hour, 180°C for 1 hour, and 250°C for 1 hour, then raised to 310°C, and at this temperature. It was held for 3 hours. The reaction mixture was then cooled and ground, washed twice with hot acetone, twice with hot water, and once with hot acetone to quantitatively obtain a pale yellow-white solid. This product has crystallinity and is dissolved in concentrated sulfuric acid at 25°C.
The intrinsic viscosity measured at is 1.2, Tm is 323℃,
Tg was 150°C. The difference in Tm and Tg compared to Example 1 is in the structural unit () as described in the text.
This seems to be because the concatenation formats of and () are different. That is, in Example 1 In contrast to the structural units in Example 3, which are generated preferentially, This is thought to be due to the fact that structural units are preferentially generated. The film obtained in the same manner as in Example 1 was extremely tough against repeated folding. Example 4 Using the same apparatus as in Example 1, 4,4'-
Difluoroterephthalophenone 6.44g (0.020mol), 4-hydroxythiophenol 5.04g
(0.040 mol), anhydrous sodium carbonate 2.12 g (0.020
mol), 40 ml of sulfolane, and 10 ml of toluene,
Heating was started under a nitrogen atmosphere. After maintaining the temperature at which toluene refluxed for 1 hour, the produced water was azeotropically removed with toluene. Next, after holding at 150℃ for 1 hour and 200℃ for 1 hour, cooling, and 6.44g of 4,4'-difluoroterephthalophenone.
(0.020 mol), anhydrous sodium carbonate 2.12 g (0.020
mol), 10 ml of toluene was added and held at the temperature where the toluene refluxed for 1 hour to remove the produced water azeotropically with the toluene, then held at 150°C for 1 hour, 180°C for 1 hour, and 250°C for 3 hours. did. After cooling, the same operation as in Example 1 was performed to obtain a solid with a yield of 94%. This product has an intrinsic viscosity of 1.1, Tm324℃, Tg152
℃ and had crystallinity. Example 5 Using the same apparatus as in Example 1, 4,4'-
Difluoroterephthalophenone 12.88g (0.040mol), 4-hydroxythiophenol 5.04g
(0.040 mol) and 40 g of diphenyl sulfone were added.
Heating was started under a nitrogen atmosphere, and when the temperature reached 220°C, 4.2 g (0.040 mol) of anhydrous sodium carbonate was added to carry out polymerization, and the temperature was finally raised to 310°C and held at this temperature for 3 hours. . After cooling and pulverizing, the mixture was washed twice with hot acetone, twice with hot water, and once with warm acetone to quantitatively obtain a polymer. The polymer had an intrinsic viscosity of 0.65, and was confirmed to be crystalline by X-ray diffraction. Example 6 Using the same equipment as in Example 1, 6.44 g (0.020 mol) of 4,4'-difluoroterephthalophenone, 5.04 g of 4-hydroxythiophenol
(0.040 mol), anhydrous sodium carbonate 1.70 g (0.016
mol) and 30 g of diphenylsulfone were added, and heating was started under a nitrogen atmosphere. After holding at 140°C for 4 hours, it was cooled to 100°C, and then 6.44 g (0.020 mol) of 4,4'-difluoroterephthalophenone and 2.21 g (0.016 mol) of anhydrous potassium carbonate were added and heated again to 320°C. The temperature was increased and maintained at this temperature for 4 hours. After cooling, the same operation as in Example 1 was performed to obtain a solid. This material had an intrinsic viscosity of 1.02 and a Tm of 355°C. Example 7 The same experiment as in Example 6 was repeated except that the autoclave of 1 was used and 10 times the amount of reagent was used to obtain a solid. This material had an intrinsic viscosity of 1.04 and a Tm of 354°C. A test piece with a thickness of 3.2 mm was produced from this polymer by injection molding, and each physical property value was determined. As a result, the tensile strength was 1240Kg/cm ² , the elongation at break was 60%, the flexural modulus was 42700Kg/cm ² , and the Izot impact value (with notches)
is 3.1Kg/cm, heat distortion temperature (18.6Kg/mm ² ) 167℃
It was hot. In addition, each measurement is performed using ASTM D638, D790, D256,
I followed D648. Comparative Example 1 In Example 1, the polymerization conditions were changed to 150°C for 1 hour.
The reaction was carried out in the same manner as in Example 1, except that the temperature was changed to 180°C for 3 hours. In this case, solid matter precipitated during the polymerization reaction. After the reaction was completed, the polymer was taken out in the same manner as in Example 1. This product had an intrinsic viscosity of 0.20, and an attempt was made to make a film by compression molding in the same manner as in Example 1, but no film could be obtained. Comparative Example 2 4-Hydroxythiophenol 5.04g (0.040
mol), using 30 ml of toluene and 10 ml (0.080 mol) of an aqueous sodium hydroxide solution with a concentration of 8.0 mol/concentration.
Disodium salt of 4-hydroxythiophenol was prepared, 14.20 g (0.040 mol) of 4,4'-dichloroterephthalophenone and 40 ml of sulfolane were added thereto, and polycondensation was carried out at 180°C for 3 hours under a nitrogen atmosphere. Ivy. At this time, solid matter precipitated during the polymerization at 180°C, and the solid matter did not dissolve even after 3 hours.
After the reaction was completed, the polymer was taken out in the same manner as in Example 1. The obtained polymer had an intrinsic viscosity of 0.14, and an attempt was made to form a film by compression molding in the same manner as in Example 1, but no film could be obtained. Comparative Example 3 In Example 1, 200 ml of N-methylcaprolacram was used instead of sulfolane and toluene,
When the water produced at 230°C was removed and the temperature was then maintained, solid matter precipitated. After the reaction was completed, the polymer was taken out in the same manner as in Example 1. This material had an intrinsic viscosity of 0.20, and an attempt was made to produce a film by compression molding in the same manner as in Example 1, but no film could be obtained. Reference Example 1 A polymer produced by the same method as Example 2 and a commercially available PEEK resin (manufactured by ICI, polyether ether ketone resin (Victrex
Melt index (MI), limiting oxygen index, and heat loss were measured using PEEK45P) and polyphenylene sulfide resin (Ryton PPSP-4, manufactured by Philips Corporation). The results are shown in Tables 1, 2, and 3.

【table】

[Table] As is clear from Table 1, although the polymer of the present invention has a high intrinsic viscosity,
The MI value was four times higher than that of PEEK resin. This shows that the polymer of the present invention has excellent fluidity.

[Table] The samples were measured using Toyo Seiki's candle combustion test device D-type.
As is clear from Table 2, the polymer of the present invention
It can be seen that it has superior flame retardancy compared to PEEK resin, and is equivalent to or slightly superior to polyphenylene sulfide resin.

[Table] As is clear from Table 3, the polymer of the present invention has better thermal stability by 70°C than polyphenylene sulfide resin. Furthermore, the polymer of the present invention was stable even when pressed at 400° C. for 30 minutes, and the intrinsic viscosity of the polymer did not change and no gel formation was observed. Reference Example 2 A polymer produced in the same manner on a scale 10 times that of Example 2, a commercially available PEEK resin [polyether ether ketone resin (Victrex PEEK45P) manufactured by ICI] and a polyphenylene sulfide resin ( Manufactured by Philips, Light PPS R
-4) was used to measure the limiting oxygen index. The results are shown in Table 4.

【table】

[Table] As is clear from this table, there was a clear difference between the No. A-1 test piece (thickness 3.0 mm) and the No. B-1 film. That is, the polymer of the present invention is
It exhibited extremely good flame retardancy compared to PEEK resin, and higher than that of polyphenylene sulfide resin, which is said to have excellent flame retardancy.

[Brief explanation of drawings]

Figures 1 and 2 are examples of an X-ray diffraction chart and an IR chart of the polymer of the present invention, respectively.

Claims (1)

[Claims] 1 formula The structural unit shown by and the formula A crystalline poly(ether thioether aromatic ketone) having a linear polymer structure in which structural units shown in the formula are alternately bonded, and having an intrinsic viscosity of 0.4 to 1.8. 2 Using an aliphatic or aromatic sulfone as a solvent, in the presence of at least one selected from alkali metal carbonates and bicarbonates, at a temperature within the range of 200 to 400°C, substantially equimolar characterized by polycondensing 4-hydroxythiophenol and 4,4′-dihaloterephthalophenone,
formula The structural unit shown by and the formula A method for producing a crystalline poly(ether thioether aromatic ketone) having a linear polymer structure in which structural units represented by the formula are alternately bonded, and having an intrinsic viscosity of 0.4 to 1.8.