JPH03167222A - Production of polyimide of good moldability - Google Patents

Abstract

PURPOSE:To obtain a polyimide improved in heat stability and moldability by reacting a specified aromatic diamine with a tetracarboxylic acid dianhydride in the presence of a dicarboxylic acid anhydride and imidizing the polyamic acid. CONSTITUTION:An aromatic diamine (A) of formula I (wherein X is a bivalent group of-CO-or-SO2-) is reacted with 0.9-1.0mol, per mol of component A, of a tetracarboxylic acid dianhydride (B) of formula II (wherein R is a tetravalent group selected from the group consisting of a 2C or higher aliphatic group, an alicyclic group, a monocyclic aromatic group, a condensed polycyclic aro matic group and a noncondensed polycyclic aromatic group consisting of aro matic groups bonded directly or through bridging members) at 0-250 deg.C for 4-24hr in an organic solvent in the presence of 0.001-1.0mol, per mol of component A, of a dicarboxylic acid anhydride (C) of formula III (wherein Z is a bivalent group of a 1-10C aliphatic group or an alicyclic group) to obtain a polyamic acid. This polyamic acid is dehydrated by heating to 100-400 deg.C or imidized with an imidizing agent to obtain the title polyimide having repeating units of formula IV as an essential skeleton.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a polyimide resin for melt molding, and more particularly to a method for producing a polyimide having good thermal stability and excellent moldability. [Prior art] Polyimide obtained by the reaction of tetracarboxylic dianhydride and dianhydride has not only high heat resistance but also excellent mechanical strength and dimensional stability, flame retardancy, electrical insulation properties, etc. It is used in fields such as electrical and electronic equipment, aerospace equipment, and transportation equipment, and is expected to be widely used in fields that require high heat resistance in the future. Hitherto, various types of solid metal have been developed that exhibit excellent properties. However, even if it has excellent heat resistance, it does not have a clear glass transition temperature, so it must be processed using methods such as sintering when used as a molding material, and it has excellent processability. However, it had advantages and disadvantages in terms of performance, such as the glass turning temperature was low and it was soluble in halogenated hydrocarbons, making it unsatisfactory in terms of heat resistance and solvent resistance. On the other hand, T. L. SL. Claire Proger and others previously developed the following general formulas (V) and (Vl) (V) (Vl) as polyide ξ which has excellent mechanical properties, thermal properties, electrical properties, solvent resistance, etc. and has heat resistance. (In the formula, R is an aliphatic group having 2 or more carbon atoms, L, a cycloaliphatic group, a monocyclic aromatic group, a fused polycyclic aromatic group, or an aromatic group in which aromatic groups are mutually linked directly or through a bridge member. They have discovered a polyimide having a repeating structural unit represented by a tetravalent group selected from the group consisting of connected non-fused polycyclic aromatic groups (Int. J. Adhesion and Adhesi).
ve 4, No. 2, Shizuka Ril 1984, and JP-A-62-53372). -L polyimide is a new heat-resistant resin that has many good physical properties. However, although the above-mentioned polyimide exhibits excellent fluidity and good processability, it has a high melt viscosity and is difficult to injection mold when compared to engineering plastics that can be extruded or injection molded. , extrusion is difficult. Therefore, film, etc. +! ! When building
It was in the form of boric acid and the only option was to use the casting method. [Problems to be Solved by the Invention] An object of the present invention is to provide a method for producing a polyimide that has excellent shapeability in addition to the excellent properties that polyimide inherently has. [Means for Solving the Problems] In order to solve the above problems, the present inventors conducted extensive research and succeeded in the present invention. That is, the present invention provides a method for producing polyimide in which a diamine and a tetracarboxylic dianhydride are reacted and the resulting polyamic acid is thermally or chemically oxidized, in which (a) the diamine is It is an aromatic diamine represented by the general formula (1) (wherein, X represents a divalent group of -CO- or -SOt); ■00 1j11 II II O0 (wherein, R is an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group, a monocyclic aromatic group, a fused polycyclic aromatic group, or an aromatic group in which the aromatic group is directly or a bridge member) (3) is a tetracarboxylic dianhydride represented by (representing a tetravalent fire selected from a certain group of non-fused polycyclic aromatic groups interconnected with each other); In the presence of a dicarboxylic acid anhydride represented by the formula (I[[)9 (wherein 2 represents a divalent group of an aliphatic group or a cycloaliphatic group having 1 to 10 carbon atoms) (2) The amount of tetracarboxylic dianhydride is 0.9 to 1.0 molar ratio per 1 mol of aromatic diamine, and the amount of dicarboxylic acid anhydride is 0.0 per 1 mol of aromatic diamine.
01 to general formula (IV) 1.0 molar ratio, having a repeating structural unit represented by (wherein X and R have the same meanings as above) as a basic skeleton and having good moldability. This is a method for producing polyimide. The diamine used in the method of the present invention is an aromatic diamine compound represented by the general formula (1), ie, bis(3-agonophenyl)sulfone or 3,3' diaminobenzophenone. Moreover, there is no problem in replacing a part of the above-mentioned diamines with other diamines as long as the good physical properties of the polyimide obtained by the method of the present invention are not impaired. Examples of diamine compounds that can be used as partial substitutes include monophenylenediamine, 0-phenylenediamine, p-phenylenediamine, toaminobenzylamine, p-aminobenzylamine, bis(3-andanophenyl )ether,
(3-7 minophenyl) (4-aminophenyl)
Ether, bis(4-aξnophenyl) ether, bis(3-aξnophenyl) sulfide, (3-aminophenyl)(4-aminophenyl) sulfide, bis(4-
Aminophenyl) sulfy F, bis(3-aminophenyl) sulfoxide, (3-acunophenyl)(4-aminophenyl) sulfoxide, bis(4-aminophenyl) sulfoxide, (3-aξnophenyl)(4-aminophenyl) sulfone , bis(4-anξnophenyl)sulfone, 3,4"-diagonobenzophenone, 4.4゜-
Diaminobenzophenone, 3,3'-diaxinodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaxinodiphenylmethane, bis(4-(3
75 nophenoxy)phenyl)methane, bis[4(4-
agonophenoxy)phenyl]methane, 1.1. Screw(
4-(3-Aξnov↓noxy)phenyl)ethane, l,
1-bis(4-(4-anophenoxy)phenyl)ethane, 1.2-bis(4-(3-agonophenoxy)phenyl)ethane, 1.2-bis(4-(4-aminophenoxy) ) phenyl]ethane, 2.2-bis(4-(3aminophenoxy)phenyl)propane, 2.2bis(4
-(4-aminophenoxy)phenyl]propane, 2-
+4-(3-aminophenoxy)phenyl l-2-[4
-(3-aminophenoxy)-3-methylphenyl 1-propane, 2,2-bis[4-(3-aminophenoxy)-3methylphenyl 1-propane, 2-14-(3-aminophenoxy)phenyl-2-[4- (3 ~aminophenoxy-3,5-dimethylphenyl 1 propane, 2,2-bis[4-(3-aminophenoxy)-3.
5-dimethylphenyl propane, 2,2-bis(4
-(3-aminophenoxy)phenyl)butane, 2.2
-bis(4-(4-agonophenoxy)phenyl]butane, 2.2-bis[4-(3-aminophenoxy)phenyl) -1.1,1,3.3.3-hexafluoropropane, 2 .2-bis(4-(4-aminophenoxy)
phenyl)-1.1.1,3.3.3-hexafluoropropane, .4-bis(3-aminophenoxy)henzen, 1
, 4-bis(4-agonophenotsi)Hensen, 4.
4'-bis(3-aminophenoxy)biphenyl, 4.
4"-bis(4-aminophenoxy)biphenyl, 4.
4′-bis(3-agonophenoxy)-3.3′-dimethylbiphenyl, 4.4′-bis(3-aminophenoxy)-3.5′-dimethylbiphenyl, 4,4′-bis(3- aminophenoxy) -3,5"-dimethylbiphenyl, 4.4"-bis(3-aminophenoxy)
-3,3゜55゛-tetramethylbiphenyl, 4,4
-Hys(3-aminophenoxy) -3.3'-dichlorohyphenylene, 4,4'-bis(3-aminophenoxy) -3,5-dichlorobiphenyl, 4.4'-bis(3-aminophenol) C) -3.3'. 5
．． 5”-Te1-lachlorobiphenyl, 4.4bis(3-
aminophenoxy) -3.3-dibutylmobiphenyl, 4.4'-bis(3-aminophenoxy) -3.5
Dibromobiphenyl, 4,4゜-bis(3-aminophenoxy)-3.3',5.5'-tetrabromobiphenylene, bis[4-(4-aminophenoxy)phenol]ketone, bis(4-( 3-Aξnophenoxy)phenol)ketone, bis(4-(3-aminophenoxy)
phenyl] sulfide, bis(4-(4-aminophenoxy)phenyl) sulfide, bis(4-(3-acunophenoxy)phenyl]-3-methoxyphenyl] sulfide, (4-(3-aminophenoxy)phenyl)
(4-(3-aminophenoxy)-3.5-dimethoxyphenyl] sulfide, bis(4-(3-aminophenoxy)-3.5-dimethoxyphenyl) sulfide,
Bis(4-(3-aminophenoxy)phenol)snorrefoxide, bis(4-(4-aminophenoxy)phenyl)sulfoxide, bis(4-(3-aminophenoxy)phenyl)sulfone, bis(4-(4-aminophenoxy)phenyl) ] Sulfone, bis(4-(3aminophenoxy)phenyl)ether, bis[4-(4-aξ
nophenoxy) phenyl] ether, 1,4-bis(
4-(3-a

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to Examples and Comparative Examples. Example 1 212 g of 3,3'-diaminobenzophenone was placed in a reaction vessel equipped with a stirrer, a reflux condenser, and a nitrogen inlet tube.
(1.0 mol), N,N-dimethylacetate 29
Charge 70g and heat at room temperature under nitrogen atmosphere at 3,3°,4
,4'-benzophenonetetracarboxylic dianhydride 31
2 g (0.97 mol) was added in portions while being careful not to increase the solution temperature, and the mixture was stirred at room temperature for about 20 hours. To this polyamic acid solution, 13.6 g (0.12 mol) of glutaric anhydride was added at room temperature under a nitrogen atmosphere, and the mixture was further stirred for 1 hour. Then 202 g (2 moles) was added to this solution.
of triethylamine and 306 g (3 moles) of acetic anhydride were added dropwise. Approximately 1 hour after the completion of the dropwise addition, yellow powder began to precipitate. The mixture was further stirred at room temperature for 10 hours and filtered. Further, dispersion washing in methanol, filtration separation, 180
470g of polyimide powder was obtained by drying for 2 hours at "C".The glass transition temperature of this polyimide powder was 250°C, and the melting point was 298°C (according to the DSC method. The same applies hereinafter).
．． In addition, the logarithmic viscosity of this polyimide powder is 0.52a/g
Met. Here, the logarithmic viscosity is determined using a mixed solvent of parachlorophenol:phenol (weight ratio 90:10), and the concentration is 0.5g/100++J! This is a value measured at 35°C in a solvent. Using the powdered powder obtained in this example, the melt viscosity and pressure (!
We measured the relationship between the Figure 1 shows the relationship between melt viscosity and shear rate measured at various shear rates after being maintained at a temperature of 380°C for 5 minutes. Comparative Example 1 464 g of polyimide powder was obtained in exactly the same manner as in Example 1, except that the reaction with glutaric anhydride was not performed. The logarithmic viscosity of the obtained Bolii Dando powder was 0.52 a/g. Using this polyimide, the melt viscosity was measured using a flow tester in the same manner as in Example 1, and the results shown in FIG. 1 were obtained. Compared to the polyamide obtained in Example 1, the melt viscosity in the low shear rate region was higher, indicating inferior processability. Example 2 212 g (1.0 mol) of 3,3゜-diaminobenzophenone and 2970 g of N,N-dimethylacetate were charged into a reaction apparatus similar to that of Example 1, and the mixture was heated at room temperature under a nitrogen atmosphere for 9 hours. .22 g (0.66 mol) of 1,2-cyclohexanedicarboxylic anhydride and 312 g (0.97 mol) of 3.3'. 4.4'-Penzophenonetetracarboxylic dianhydride was added while being careful not to raise the solution temperature, and the mixture was stirred at room temperature for about 20 hours. Then, 202 g (2 moles) of triethylamine and 306 g (3 moles) of acetic anhydride were added dropwise to this solution. After stirring for 20 hours, a pale yellow slurry was obtained. This slurry was filtered, washed with methanol, and dried under reduced pressure at 180°C for 8 hours to obtain 486 g of pale yellow powder.
The glass transition temperature of this powder was 250°C, the melting point was 298°C, and the logarithmic viscosity was 0.50 a/g. The shape stability of the polyimide obtained in this example was measured by changing the residence time in the cylinder of a flow tester. Cylinder temperature is 380℃, pressure is 100kg/c+++"
I went there. The results are shown in Figure 2. Even if the residence time in the cylinder becomes longer, the melt viscosity hardly changes, indicating that the molding stability is good. Comparative Example 2 A pale yellow polyimide $ was prepared in exactly the same manner as in Example 2, except that 1,2-cyclohexanedicarboxylic anhydride was not used.
5) Got the end. The glass transition temperature of the Borii powder was 250'C, and the logarithmic viscosity was 0.50 di/g. As in Example 2, the residence time in the flow tester cylinder was varied and the melt viscosity was measured. As the residence time became longer, the melt viscosity increased, and compared to the solid gold obtained in Example 2, the melt viscosity increased. It was shown that the stability was poor. The results are shown in Figure 2. Example 3 Into a reactor similar to Example 1 were added 212 g (1.0 mol) of 3,3°-diajunobenzophenone, 3.3'. 4.
4'-benzophenonetetracarboxylic dianhydride 315
．． l3g (0.98 mol), citraconic anhydride 4.5g
(0.04 mol) and 2970 g of Tocresol were charged, and the temperature was raised while stirring under a nitrogen atmosphere.
It became a brown transparent homogeneous solution at around 120℃, 150
When heated to 'C and continued stirring, yellow polyimide powder began to precipitate in about 20 minutes. After further stirring under heating for 2 hours, the mixture was filtered to obtain polyimide I). This polyimide powder was washed with methanol and acetone, and then dried under reduced pressure at 180°C for 8 hours to obtain 474 g of polyimide powder. This polyimide powder had a logarithmic viscosity of 0.57 a/g, a glass transition temperature of 251''C, and a melting point of 298°C.
Repeated extrusion measurements were carried out using a flow tester at a temperature of 400''C and a pressure of 100 kg/c++''. That is, it was held at 380°C for 5 minutes and extruded at a pressure of 100kg/cm2. The resulting strand was crushed and extruded under the same conditions five times in a row. Almost no change in viscosity was observed depending on the number of repetitions. Figure 3 shows the results. Example 4 In the same reactor as in Example 3.3' in Example I
- 212 g (1.0 mol) of diaξnobenzophenone was mixed with 248 g (1.0 mol) of bis(3-aεnophenol) sulfone.
A boria ξ-doic acid solution was obtained by carrying out the reaction in exactly the same manner except that the amount of mol) was changed. Anhydrous glutaric acid M 17.03 (0.0%) was added to this boria ξ-doic acid solution at room temperature under a nitrogen atmosphere.
15 mol) was added and stirred for an additional hour. Then,
At this time, 202 g (2 monooles) of triethylamine and 306 g (3 moles) of acetic anhydride were added dropwise. Approximately 1 hour after the dropping was completed, seedling-colored polyimide powder began to precipitate. The mixture was further stirred at room temperature for 10 hours and filtered. Further, it was dispersed and washed in methanol, filtered, and dried at 180'C for 2 hours to obtain 506 g of polyimide particles. The glass transition temperature of this polyimide powder was 269°C. The glass transition temperature of this polyimide powder was 269°C (based on DSC, hereinafter the same). Also, this polyimide
The logarithmic viscosity of was 0.51 di/g. The relationship between melt viscosity and pressure (shear rate) was measured in the same manner as in Example 1. FIG. 4 shows the relationship between melt viscosity and shear rate measured at various shear rates after being maintained at a temperature of 380'C for 5 minutes. Comparative Example 3 In exactly the same manner as in Example 4, but without performing the operation of reacting glutaric anhydride, 496 g of polyimide 15]
obtained the Song Dynasty. The logarithmic viscosity of the obtained polyimide powder was 0.51a/g. Example using this Bolii godo powder! The melt viscosity was measured using a flow tester in the same manner as above, and the results shown in Figure 4 were obtained. Example 5 It can be seen that the melt viscosity is higher in the low shear rate region than the polyimide obtained in Example 4, and the formability is inferior to the polyimide obtained in Example 4. Reactor similar to Example 1 212 g (1.0 mol) of bis(3-anξnophenyl)sulfone and 3170 g of N,N-dimethylacetamide were charged, and 9.22 g (0.06 mol) of 1. 2-cyclohexanedicarboxylic anhydride, 312 g (0.97
mol) of 3.3',4.4'-benzophenonedicarboxylic dianhydride was added while being careful not to increase the solution temperature,
Stir at room temperature for about 20 hours. 202 g (2 mol) of triethylamine and 306 g (3 mol) of acetic anhydride were then added dropwise to this solution. The mixture was stirred for 20 hours to form a pale yellow slurry. The slurry was filtered, washed with methanol [8
It was dried under reduced pressure for hours to obtain 475 g of pale yellow powder. This polyimide powder had a glass transition temperature of 250'C, a melting point of 298°C, and a logarithmic viscosity of 0.50 dl/g. The stability of the polyimide obtained in this example was measured by varying the residence time in the cylinder of a flow tester. The temperature was 380°C and the pressure was IOOJ/c+m. Comparative Example 4 Pale yellow polyimide powder was obtained in exactly the same manner as in Example 5 without using 1,1,2-cyclohexanedicarboxylic anhydride. The glass transition temperature of the polyimide powder was 250°. C, the logarithmic viscosity was 0.50a'/g.As in Actual AI Example 5, the residence time in the flow tester cylinder was changed and the melt viscosity was measured. Viscosity increases, Example 5
The thermal stability was inferior to that of the polyimide obtained in . The results are shown in Figure 5. Example 6 In a reactor similar to Example 1, 248 g (1.0 mol) of bis(3-anξnophenyl)sulfone, 3.3',4
．． 4'-Benzophenonetetracarboxylic dianhydride 31
5.6g (0.98 mol), citraconic anhydride 4.48
(0.04 mol) and a total of 3170 g of cresol were charged, and the temperature was gradually increased while stirring in a nitrogen atmosphere. At around 120''C, it became a brown transparent homogeneous solution.
When heated to 50° C. and continued stirring, yellow polyimides began to precipitate in about 20 minutes. After further stirring under heating for 2 hours, the mixture was filtered to obtain polyimide powder. After washing this Boli 5 powder once each with methanol and acetone, it was dried under reduced pressure at 180°C for 8 hours, and 507 g
Polyimide powder was obtained. The logarithmic viscosity of this powder was 0.56 d1/g, and the glass transition temperature was 270°C. Same mallet as Example 1, but temperature 420'C, pressure 100
The melt viscosity was repeatedly measured using the cylinder of a flow tester at 1.5 kg/cm. Almost no change in viscosity was observed depending on the number of measurements. The results are shown in Figure 6. [Effects of the Invention] Method of the Invention According to this publication, it is possible to provide a polyimide that has excellent mechanical properties, thermal properties, electrical properties, and solvent resistance, is heat resistant, is thermally stable for a long time, and has excellent moldability.

[Brief explanation of the drawing]

1 and 4 show the relationship between the melt viscosity and shear rate of polyimide produced by the method of the present invention, and FIG. 1 shows the measurement results for the polyimide obtained in Example 1 and Comparative Example 1, Figure 4 shows the measurement results for the polyimides obtained in Example 4 and Comparative Example 3. FIGS. 2 and 5 show the relationship between the melt viscosity of polyimide produced by the method of the present invention and the residence time in the cynonder.
Figure 5 shows the measurement results for polyimide obtained in Example 5 and Comparative Example 4.

Claims (1)

[Claims] (1) In the method for producing polyimide, which involves reacting a diamine with a tetracarboxylic dianhydride and thermally or chemically imidizing the obtained polyamic acid, (a) the diamine has the general formula (I) ▲mathematical formula , chemical formulas, tables, etc. ▼ (I) (In the formula, X represents a divalent group of -CO- or -SO_2-) is an aromatic diamine, and (b) tetracarboxylic dianhydride. The product has the general formula (II) ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (II) (wherein R is an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group, a monocyclic aromatic group, A tetracarboxylic acid represented by a tetravalent group selected from the group consisting of a fused polycyclic aromatic group and a non-fused polycyclic aromatic group in which aromatics are interconnected directly or through a bridge member. It is a dianhydride, and (c) the reaction is expressed by the general formula (III) ▲ Numerical formulas, chemical formulas, tables, etc. (d) The amount of tetracarboxylic dianhydride is 0.9 to 1.0 per mole of aromatic diamine. molar ratio, and the amount of dicarboxylic acid anhydride is 0.00 per mole of aromatic diamine.
General formula (IV) with a molar ratio of 1 to 1.0 ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (IV) A repeating structural unit represented by (in the formula, X and R have the same meanings as above) A method for producing polyimide having good moldability and having as a basic skeleton.