JPH07292249A - Composition of polyimide resin - Google Patents

Abstract

PURPOSE:To obtain a resin composition excellent in heat resistance, moldability, mechanical strengths, etc., by mixing a polyimide resin comprising repeating units represented by a specified formula and aromatic polyamide fibers. CONSTITUTION:This composition is a polyimide resin composition comprising 100 pts.wt. polyimide resin comprising repeating units repre by the formula (wherein Y is a 1-10 C bivalent hydrocarbon, hexafluoroisopropylidene, carbonyl, thio, sulfinyl or oxide; and R is a tetravalent group selected from the group consisting of a 2C or higher aliphatic group, a cycloaliphatic group, a monocyclic aromatic group, a fused polycyclic aromatic group and a nonfused cyclic aromatic group composed of aromatic groups bonded to each other directly or through bridging members) and 5-100 pts.wt. aromatic polyamide fibers. Thin composition is a material having excellent moldability and mechanical strengths as well as heat resistance and being useful for electrical and electronic components, automotive components, precision machinery components, etc.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention has significantly improved molding processability and mechanical strength without impairing the heat resistance of the resin.
The present invention relates to a novel polyimide resin composition.

[0002]

2. Description of the Related Art Polyimides obtained by the reaction of tetracarboxylic dianhydride and diamine are expected to be widely used in fields where heat resistance is required in the future due to various excellent physical properties and good heat resistance. Has been done. Many of the polyimides developed so far have excellent properties, but they have excellent heat resistance, but are poor in processability, and resins developed for the purpose of improving processability have heat resistance and solvent resistance. There were merits and demerits in performance such as inferiority. For example, the formula (I
I)

[Chemical 2] Polyimide consisting of a basic skeleton as shown in (DuPont: trade name Kapton, Vespel) is a polyimide with excellent heat resistance without a clear glass transition temperature, but it is processed when used as a molding material. However, it must be processed by using a technique such as sinter molding. Further, when it is used as a material for electric / electronic parts, it has a property of high water absorption which adversely affects dimensional stability, insulation and solder heat resistance.

Also, the formula (III)

[Chemical 3] Polyetherimide having a basic skeleton represented by (General Electric Co., Ltd .: trade name ULTEM)
Is a resin with excellent processability, but has a glass transition temperature of 21.
It is as low as 7 ° C, is soluble in halogenated hydrocarbons such as methylene chloride, and is not a satisfactory resin in terms of heat resistance and solvent resistance.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a novel polyimide resin composition having excellent moldability and mechanical strength without impairing the heat resistance of the resin.

[0005]

Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned object, the present inventors have found that a polyimide resin composition comprising a novel polyimide and a specific amount of aromatic polyamide fiber is particularly effective. That is, the present invention has been completed.

That is, the polyimide resin composition of the present invention has the formula (I)

[Chemical 4] (In the formula, Y represents a group selected from the group consisting of a divalent hydrocarbon group having 1 to 10 carbon atoms, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group or an oxide, and R Is an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group, a monocyclic aromatic group, a condensed polycyclic aromatic group, or a non-condensed cyclic aromatic group in which aromatic groups are connected to each other directly or by a crosslinking member. A polyimide resin composition comprising 100 parts by weight of a polyimide resin having a repeating unit represented by a tetravalent group selected from the group consisting of group groups and 5 to 100 parts by weight of an aromatic polyamide fiber.

The polyimide resin usable in the present invention has the formula (IV)

[Chemical 5] (In the formula, Y represents a group selected from the group consisting of a divalent hydrocarbon group having 1 to 10 carbon atoms, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group and an oxide.) A polyimide obtained by dehydrating and cyclizing a polyamic acid obtained by reacting the ether diamine shown in 1) with one or more tetracarboxylic acid dianhydrides.

As the ether diamine, bis [4-
(3-Aminophenoxy) phenyl] methane, 1,1-
Bis [4- (3-aminophenoxy) phenyl] ethane, 1,2- [4- (3-aminophenoxy) phenyl] ethane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2 , 2-bis [4- (3-aminophenoxy) phenyl] butane, 2,2-bis [4
-(3-Aminophenoxy) phenyl] -1,1,1,
3,3,3-hexafluoropropane, bis [4- (3
-Aminophenoxy) phenyl] ketone, bis [4-
(3-Aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfoxide, bis [4- (3-aminophenoxy) phenyl] ether and the like can be mentioned, and these can be used alone or in admixture of two or more. Used.

The tetracarboxylic dianhydride has the formula (V)

[Chemical 6] (In the formula, R is an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group,
It represents a tetravalent group selected from the group consisting of a monocyclic aromatic group, a condensed polycyclic aromatic group, and a non-condensed cyclic aromatic group in which aromatic groups are connected to each other directly or by a bridging member. ) Is a tetracarboxylic acid dianhydride.

That is, as the tetracarboxylic dianhydride used, ethylenetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, pyromellitic dianhydride, 3,3 ', 4,4' -Benzophenone tetracarboxylic dianhydride, 2,2 ', 3,3'-benzophenone tetracarboxylic dianhydride, 3,3', 4,4'-
Biphenyl tetracarboxylic dianhydride, 2,2 ', 3
3'-biphenyltetracarboxylic dianhydride, 2,2-
Bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-Dicarboxyphenyl) sulfone dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (2,3-
Dicarboxyphenyl) methane dianhydride, bis (3,4
-Dicarboxyphenyl) methane dianhydride, 2,3
6,7-naphthalenetetracarboxylic dianhydride, 1,
4,5,8-naphthalenetetracarboxylic dianhydride,
1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,2,3,4-benzenetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2, 3,6,7-anthracene tetracarboxylic dianhydride, 1,2,7,8-phenanthrene tetracarboxylic dianhydride, etc. are mentioned. These tetracarboxylic dianhydrides may be used alone or in admixture of two or more.

The ether diamine and the tetracarboxylic dianhydride are usually converted into a polyamic acid represented by the formula (VI) by a known method, and then converted into a polyimide.

[Chemical 7] (In the formula, Y represents a group selected from the group consisting of a divalent hydrocarbon group having 1 to 10 carbon atoms, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group or an oxide, and R Is an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group, a monocyclic aromatic group, a condensed polycyclic aromatic group, or a non-condensed cyclic aromatic group in which aromatic groups are connected to each other directly or by a crosslinking member. Represents a tetravalent group selected from the group consisting of group groups.)

The aromatic polyamide fiber used in the present invention is a relatively new heat-resistant organic fiber, and it is expected to be developed into various fields by taking advantage of many unique characteristics. Specific examples include those having the following structural formulas, and at least one kind or a mixture of two or more kinds thereof is used.

[Chemical 8] In addition, there are aromatic polyamide fibers having various skeletons due to the ortho, meta, and para isomer structures. Among them, the para-para-para bond of (1) has a high softening point and melting point and is used as a heat-resistant organic fiber in the present invention. Most preferred.

The aromatic polyamide fiber in the present invention can be used in an amount of 5 to 100 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the polyimide resin. When the amount is 5 parts by weight or less, the composition having excellent moldability and mechanical strength, which is a feature of the present invention, cannot be obtained. Further, when 100 parts by weight or more is used, the fluidity of the composition at the time of molding is remarkably improved, but the heat distortion temperature is lowered, and satisfactory heat resistance cannot be obtained.

The polyimide resin composition according to the present invention can be produced by a generally known method, but the following method is particularly preferable. (1) The polyimide powder and the aromatic polyamide fiber are premixed by using a mortar, a Henschel mixer, a drum blender, a tumbler blender, a ball mill, a ribbon blender, etc., and then kneaded by a commonly known melt mixer, hot roll, etc. , Pellet or powder.

(2) Polyimide powder is previously dissolved or suspended in an organic solvent, the solution or suspension is impregnated in aromatic polyamide fiber, and then the solvent is removed in a hot air oven, and then pellets or Make into powder. In this case, as the solvent, for example, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylmethoxyacetamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2- Imidazolidinone, N-methylcaprolactam,
1,2-dimethoxyethane, bis (2-methoxyethyl) ether, 1,2-bis (2-methoxyethoxy)
Ethane, bis [2- (2-methoxyethoxy) ethyl]
Ether, tetrahydrofuran, 1,3-dioxane,
1,4-dioxane, pyridine, picoline, dimethyl sulfoxide, dimethyl sulfone, tetramethylurea, hexamethylphosphoramide and the like can be mentioned. These organic solvents may be used alone or in combination of two or more.

(3) After the aromatic polyamide fiber is impregnated with a solution of a polyamic acid having a repeating unit represented by the formula (VI), which is a precursor of the polyimide of the present invention, in the organic polyamide, After heat treatment at 400 ° C. or chemical imidization using a commonly used acetic anhydride and an imidizing agent such as triethylamine, the solvent is removed and pellets or powders are obtained. With respect to the composition of the present invention, as long as the object of the present invention is not impaired, antioxidants and heat stabilizers, ultraviolet absorbers, flame retardant aids, antistatic agents, lubricants, colorants, etc. One or more additives can be added.

Other thermoplastic resins (for example, polyethylene, polypropylene, polyamide, polycarbonate, polysulfone, polyether sulfone, polyether ether ketone, modified polyphenylene oxide, polyphenylene sulfide, etc.), thermosetting resins (for example, phenol resin) , Epoxy resin, etc.) or clay, mica, silica, graphite, glass beads, alumina, calcium carbonate and the like fillers may be added in an appropriate amount according to the purpose. The polyimide resin composition of the present invention is molded for practical use by a known molding method such as an injection molding method, an extrusion molding method, a compression molding method, and a rotational molding method.

[0018]

EXAMPLES The present invention will be described below with reference to examples. Synthesis Example-1 In a 1 liter glass reaction vessel, 2,2-bis (4-hydroxyphenyl) propane 85.6 g (0.375 mol), m-dinitrobenzene 151.2 g (0.9 mol), potassium carbonate 124 0.6 g and 660 ml of N, N-dimethylformamide are charged and the reaction is carried out at 145-150 ° C. for 10 hours. After the reaction is completed, it is cooled and filtered, and KNO _{2 is} added.
And then the solvent of the filtrate was distilled off under reduced pressure, cooled to 65 ° C., and charged with 450 ml of methanol to 1.0
Stir for hours. The crystals are filtered off, washed with water, washed with methanol,
Dried to 2,2-bis [4- (3-nitrophenoxy)
Yellowish brown crystals of phenyl] propane were obtained. Yield 164.
8 g (yield 93.5%). Then, 100 g (0.21 mol) of crude 2,2-bis [4- (3-nitrophenoxy) phenyl] propane, 10 g of activated carbon, 1 g of ferric chloride hexahydrate and 1 g of methyl cellosolve were placed in a 500 ml glass reaction vessel. Charge 300 ml and stir for 30 minutes under reflux.
Next, at 70 to 80 ° C, 42 g of hydrazine hydrate (0.84
Mol) is added dropwise over 2 hours. 5 at 70-80 ° C
Stir for hours. After cooling, the catalyst is removed by filtration and 150 ml of methyl cellosolve are distilled off. 20% hydrochloric acid aqueous solution 270
g, and then 30 g of salt, and while stirring, 20 to
Crystals precipitate when cooled to 25 ° C. After filtering this off, 3
Crystals precipitate when neutralized with aqueous ammonia in 0% IPA / water. This was separated by filtration, washed with water, dried and then recrystallized from a mixed solvent of benzene and n-hexane to obtain 2,2-bis [4- (3-aminophenoxy) phenyl] propane. Yield 69.2 g (75% yield) Colorless crystals mp. 106 to 108 ° C. Purity 99.5% (by high performance liquid chromatography) Elemental analysis C H N calculated value (%) * 79.02 6.34 6.83 Analysis value (%) 79.21 6.40 6.71 *) C ₂₇ H ₂₆ N ₂ as ^{_{O 2 MS: 470 (M +}} ), 455 (M-CH 3) + IR (KBr, cm -1): 3460 and 3370 (NH ₂
Group), 1200 (ether bond)

Synthesis Example-2 In a 3 liter glass reaction vessel, 218 g (1 mol) of 4,4'-dihydroxydiphenyl sulfide, 403 g (2.4 mol) of m-dinitrobenzene, 33 potassium carbonate.
1 g (2.4 mol) and 2.5 liters of N, N-dimethylformamide were charged and reacted at 145 to 150 ° C for 20 minutes. After completion of the reaction, the mixture was cooled and filtered, and the solvent was distilled off under reduced pressure from the filtrate. After cooling to 65 ° C, methanol 8
Charge 00 ml and stir for 1 hour. The obtained crystals were separated by filtration, washed with methanol and then dried to obtain 429 g (yield 92.3%) of 4,4'-bis (3-nitrophenoxy) diphenyl sulfide crystals. Then, 428 g (0.93 mol) of this crude product was placed in a 3 liter glass reaction vessel, charged with 22.6 g of activated carbon, 0.9 g of ferric chloride hexahydrate and 1.5 liter of methyl cellosolve. The mixture was stirred under reflux for 30 minutes. Then 110-1
115.2 g (3.1 mol) of hydrazine hydrate at 15 ° C
Was added dropwise over 2 hours, and the mixture was further stirred under reflux for 3.5 hours. After cooling, the catalyst was filtered off and the solution was concentrated under reduced pressure. Then, 205 ml of 35% hydrochloric acid, 1120 ml of water and 480 ml of isopropyl alcohol were added and dissolved by heating. Then, 20 g of activated carbon was charged and hot filtration was performed. Then salt 1
12 g was added and cooled, and the precipitated crystals of hydrochloride were filtered off. The obtained crystals are neutralized with aqueous ammonia by a conventional method,
The target 4,4'-bis (3-aminophenoxy) diphenyl sulfide was obtained. Yield 265 g (yield 66
%). Colorless crystals mp. 112 to 113 ° C. (corr.) Purity 99.9% or more Elemental analysis C H N S calculated value (%) * 71.97 5.03 7.00 8.01 Analytical value (%) 71.90 4.54 6 .92 7.72 *) as C ₂₄ H ₂₀ N ₂ O ₂ S MS (FD): 400 (M ⁺ ) IR (KBr, cm ⁻¹ ): 3390 and 3300 (NH ₂
Group), 1220 (ether bond)

Example 1 In a container equipped with a stirrer, a reflux condenser and a nitrogen inlet tube, 41.2 kg (100 mol) of 2,2-bis [4- (3-aminophenoxy) phenyl] propane and N were added. , N-
Charge 189 kg of dimethylacetamide, and under a nitrogen atmosphere at room temperature, 21.8 kg (100 mg of pyromellitic dianhydride).
(Mol) was added in portions while paying attention to the rise in solution temperature, and the mixture was stirred at room temperature for about 20 hours. The polyamic acid thus obtained had an inherent viscosity of 2.40 dl / g. Further, 337.5 kg of N, N-dimethylacetamide was added to 150 kg of the polyamic acid solution, and the mixture was heated to 70 ° C. under stirring in a nitrogen atmosphere and then 26.1 kg (26 mol).
When acetic anhydride and 9.05 kg (9 mol) of triethylamine were added dropwise, yellow polyimide powder began to precipitate within about 10 minutes after the addition was completed. Got the powder. The polyimide powder was washed with methanol and dried under reduced pressure at 150 ° C. for 5 hours to obtain 34.7 kg (yield 98%) of polyimide powder. Aromatic polyamide fiber having an average fiber length of 3 mm (100% by weight of the obtained polyimide powder, manufactured by DuPont,
The product name Kevlar) was added in the amount shown in Table-1 and mixed with a drum blender mixer (manufactured by Kawada Manufacturing Co., Ltd.), and then the caliber was 30
After melt-kneading with a mm single-screw extruder at a temperature of 390 ° C., the strand was air-cooled and cut to obtain pellets. The obtained pellets are injection-molded (Arburg injection molding machine (maximum mold clamping force 35 tons) injection pressure 500 kg / cm ² , cylinder temperature 400 ° C, mold temperature 180 ° C), tensile test pieces, bending test pieces, Izod An impact test piece was obtained. Tensile test to ASTM D-638, Bending test to ASTM D-638
D-790, Izod impact test is ASTM D-2
56, the heat distortion temperature was measured according to ASTM D-648. In addition, the glass transition point was measured. The fluidity test at the time of molding is performed under the above injection molding conditions (injection pressure 500 kg
/ Cm ² , cylinder temperature 400 ℃, mold temperature 180 ℃)
In, the flow length was measured by a spiral flow having a width of 10 mm and a wall thickness of 2.0 mm. The above test results are shown in Table 1.

Examples 2 to 3 and Comparative Example 1 The aromatic compound used in Example 1 with respect to 100 parts by weight of the polyimide powder obtained from the diamine and tetracarboxylic dianhydride shown in Tables 1 and 2. Polyamide fibers (manufactured by DuPont, trade name Kevlar) were added in the amounts shown in Tables 1 and 2. Then, the same operation as in Example 1 was performed to obtain the results shown in Table-1 and Table-2.

Comparative Example 2 A polyetherimide represented by the formula (III) (General Electric Co .: trade name ULTEM) was used, and Example 1 was used.
Pelletization and injection molding were performed in the same manner as in, and the same measurement as in Example 1 was performed, and the results in Table 2 were obtained.

Comparative Example 3 Polyimide manufactured by Rhone Poulin (trade name: KERIMID)
1000) was used, pelletization and injection molding were performed in the same manner as in Example 1, and the same measurements as in Example 1 were carried out to obtain the results in Table-2.

Comparative Example 4 2,4-bis [4- (4-aminophenoxy) phenyl] -1,1,1,3 was used in place of 4,4'-bis (3-aminophenoxy) biphenyl of Example 1. , 3,3-hexafluoropropane was used to obtain a polyimide powder in the same manner as in Example 1. 30 parts by weight of the same aromatic polyamide fiber as in Example 1 was added to 100 parts by weight of the obtained polyimide to attempt pelletization, but it was not melted and could not be pelletized.

Comparative Example 5 Instead of 4,4'-bis (3-aminophenoxy) biphenyl and pyromellitic dianhydride of Example 1, 2,2'-bis (4-aminophenoxy) biphenyl and 3 respectively. , 3 ′, 4,4′-Benzophenonetetracarboxylic dianhydride was used to obtain a polyimide powder in the same manner as in Example 1. To 100 parts by weight of the obtained polyimide, 30 parts by weight of the same aromatic polyamide fiber as in Example 1 was added for pelletization, but good pellets could not be obtained. Injection molding was attempted using the obtained pellets under the same conditions as in Example 1, but at 500 kg / cm ² ,
Could not be molded.

[0026]

[Table 1]

[0027]

[Table 2]

[0028]

From the results shown in Table 1, the composition of the polyimide resin of the present invention has excellent mechanical strength without impairing the heat resistance and has a very high heat distortion temperature, so that it can be used at a high temperature. Is possible. Further, since the melt fluidity at the time of molding is remarkably improved, it is a useful material for electric, electronic parts, automobile parts, precision machine parts and the like, and has a great industrial application effect.

Claims (1)

[Claims] Claims: (In the formula, Y represents a group selected from the group consisting of a divalent hydrocarbon group having 1 to 10 carbon atoms, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group or an oxide, and R Is an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group, a monocyclic aromatic group, a condensed polycyclic aromatic group, or a non-condensed cyclic aromatic group in which aromatic groups are connected to each other directly or by a crosslinking member. A polyimide resin composition comprising 100 parts by weight of a polyimide resin having a repeating unit represented by the formula (4) selected from the group consisting of group groups and 5 to 100 parts by weight of aromatic polyamide fiber.