JPH02222451A - Aromatic polyimide resin composition - Google Patents

Abstract

PURPOSE:To obtain an aromatic polyimide resin composition having excellent heat resistance and mechanical properties, etc., and improved processability by comprising aromatic polyimide resin and thermosetting poly(iso)imide oligomer having acetylene terminal. CONSTITUTION:(A) 99.9-50wt.% aromatic polyimide resin, preferably obtained from pyromellitic acid dianhydride and 4,4'-diaminodiphenylether is mixed with (B) 0.1-50wt.%, preferably 0.5-30wt.% thermosetting polyimide oligomer expressed by formula I (Ar1 is tetrafunctional aromatic residue; Ar2 is bifunctional aromatic residue; n is 0-30, preferably 1-10) and/or thermosetting polyisoimide oligomer expressed by formula II, obtained from aromatic tetracarboxylic acid dianhydride, aromatic diamine and aminophenylacetylene to afford the aimed composition.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an aromatic polyimide resin composition with improved moldability.

<Conventional technology> Due to its excellent heat resistance and mechanical properties, aromatic polyimide resins play an important role in the electrical/electronic equipment industry, the automobile industry, etc. , is becoming an indispensable material as performance advances. Among them, the polypyromellitimide resin disclosed in Japanese Patent Publication No. 39-22196 has extremely excellent heat resistance and stands at the top of the so-called heat-resistant resins, but on the other hand, it has poor fluidity. However, there is a problem that molding is difficult.

As a method for improving the moldability of such an aromatic polyimide resin, JP-A-61-163937 discloses a method in which amic acid, which is a precursor of polyimide, is left behind.

Further, JP-A-59-179558 discloses a method of mixing a thermosetting simaleimide compound, and JP-A-57-180633 discloses a method of mixing a thermosetting simalimide compound, and JP-A-57-180633 discloses a method of mixing a thermosetting simaleimide compound. A method of mixing various thermosetting resins is disclosed.

<Problems to be Solved by the Invention> However, in the method of leaving amic acid as disclosed in JP-A-61-163937, ring-closing water is generated due to imide ring-closing during molding, and voids are generated. Therefore, in order to obtain a good molded product, it is necessary to slowly raise the temperature under strict temperature control while removing gases, resulting in an extremely long molding cycle. Also, JP-A-59-179
In the method of mixing thermosetting resins as disclosed in Japanese Patent Application Laid-open No. 558 and Japanese Patent Application Laid-Open No. 57-180633,
High molding temperature of aromatic polyimide resin (-38 for boat fishing)
(0° C. or higher), the thermosetting resin thermally decomposes, making it difficult to obtain a good molded product.

Therefore, the object of the present invention is to solve the problems of these conventional molding methods and to obtain an aromatic polyimide resin composition with good moldability.

Means for Solving the Problems> That is, the present invention comprises (A) 99.9 to 50% by weight of an aromatic polyimide resin, and (8) an acetylene-terminated thermosetting polyimide oligomer and/or polymer represented by the formula The present invention provides an aromatic polyimide resin composition comprising 0.1 to 50% by weight of an acetylene-terminated thermosetting polyisoimide oligomer represented by the general formula %.

The method for producing the aromatic polyimide resin used in the present invention is publicly known, and the details are disclosed in, for example, Japanese Patent Publication No. 39-22196. and an organic polar solvent (e.g., N-methylpyrrolidone, N,N-
dimethylacetamide, -diglyme, etc.), and the resulting polyamic acid is ring-closed with dehydrated imide. Specific examples of the aromatic tetracarboxylic a2 anhydride used here include pyromellitic acid 2m hydrate, 3°3',4,4'-benzophenonetetracarvone! 2-anhydride, 3.3', 4.4'-biphenyltetracarboxylic dianhydride, 2.3.3'4'biphenyltetracarboxylic dianhydride, 2.2'3.3'-
biphenyltetracarboxylic dianhydride, 3.3',
4.4'-diphenyl ether tetracarboxylic dianhydride, 3.3',4.4'-diphenylsulfone tetracarboxylic dianhydride, 2.2-bis(3,4-dicarboxyphenyl)propane dianhydride ,2,2-bis(3,
4-dicarboxyphenyl) hexafluoropropane 2 anhydride, 1.2゜5.6-naphthalenetetracarboxylic acid 2
Examples thereof include anhydride, 2.3,6.7-naphthalenetetracarboxylic dianhydride, 1.4,5.8-naphthalenetetracarboxylic dianhydride, and the like. Further, these acid dianhydrides can also be used in the form of their derivatives such as carboxylic acids, esters, and acid chlorides.

Specific examples of aromatic diamines and aromatic diisocyanates include p-phenylenediamine, m-phenylenediamine, 2-chloro-P-phenylenediamine, benzidine, 2-chlorobenzidine, 4.4'-diaminodiphenylmethane, 4.4 '-Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'-
Diaminodiphenyl ether, 4.4'-diaminodiphenyl sulfone, 3.3'-diaminodiphenylsulfone, 4.4'-diaminodiphenyl ketone, 3.3'-
Diaminodiphenylketone, 4.4-diaminodiphenyl sulfide, 4.4'diaminoterphenyl, 1,4
-bis(4-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,3-bis(
4-aminophenoxy)benzene, 1,3-bis(3-
aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, bis(4-(4-aminophenoxy)phenylkoketone, 2,2-bis[4
-(4-aminophenoxy)phenylcopropane, 2.
Examples include 2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 4,4'-bis(4-aminophenoxy)biphenyl, and their diisocyanates.

Among them, a preferred aromatic polyimide resin is a polyimide having the following structure obtained from pyromellitic dianhydride and 4,4'-diaminodiphenyl ether.

Alternatively, this includes those in which the imide group remains in the form of an amic acid, which is its ring-closing precursor, but it is preferable that the imide group is 80% or more in order to prevent gas generation during molding. .

The acetylene-terminated polyimide or polyisoimide oligomer used as a moldability improver for aromatic polyimide resins in the present invention has a structure represented by the following formula.

Here, Ar1 represents a tetravalent aromatic residue, and Ar2 represents a divalent aromatic residue. Further, n is an integer of 0 to 30, preferably 1 to 10.

The details of the manufacturing method for these are disclosed in, for example, U.S. Pat. No. 3,845,018. be synthesized. Specific examples of the aromatic tetracarboxylic dianhydride and aromatic diamine are the same as those described above. Particularly suitable acetylene-terminated polyimide and polyisoimide oligomers include resins having the following structure sold by Kanebo NSC under the trade name "Thermid".

“Thermid” ■ “Thermid” C “Thermid” FA Further, specific examples of other acetylene-terminated oligomers include the following.

＼■, CECH These acetylene-terminated polyimide or polyisoimide oligomers are addition-type thermosetting resins, so they do not generate gas or cause problems such as blistering when heated and cured, and are compatible with phenolic resins and maleimide resins. Because it has higher heat resistance than aromatic polyimide resins, it does not decompose even under high molding temperature conditions (usually 380°C or higher), and by providing appropriate fluidity, it can significantly improve moldability. can.

Furthermore, it has been found that these acetylene-terminated oligomers have the effect of increasing the bulk density of the aromatic polyimide resin and improving the handling properties during molding. In other words, aromatic polyimide resin has poor melt fluidity,
Since the injection molding method used for ordinary resins cannot be applied, powder sintering molding is often used. At this time, there was a problem that the powder was bulky and difficult to mold.
As can be seen from the examples described later, the composition of the present invention can increase the bulk density of the powder and improve workability.

In the composition of the present invention, the amount of acetylene-terminated polyimide or polyisoimide oligomer is 0.1 to 5.
It is preferably 0% by weight, preferably 0.5 to 30% by weight, more preferably 1 to 20% by weight. If it is less than 0.1% by weight, the addition effect is poor and sufficient fluid moldability cannot be obtained, so it is preferable. However, if it exceeds 50% by weight, the properties of the aromatic polyimide resin, particularly the toughness, will be impaired, which is not preferable.

Fillers can be added to the composition of the present invention as needed to improve various properties such as heat resistance, mechanical properties, sliding properties, electrical properties, flame retardance, and chemical resistance. but,
Examples of such fillers include graphite, fluororesins, molybdenum disulfide, boron nitride, mica, talc, glass fibers, carbon fibers, aramid fibers, potassium titanate fibers, aluminum, silver, copper, lead, and various metals. Examples include oxides.

Further, in preparing the composition of the present invention, either a dry blending method or a wet blending method used for ordinary resins may be used. In particular, in order to increase the bulk density of the powder and make it easier to handle, a wet blending method is preferred, and a spray drying method is particularly preferred.

Furthermore, in order to obtain a more uniform blend, it is also possible to add an acetylene-terminated polyimide or polyisoimide oligomer during the polymerization process of the aromatic polyimide resin.

<Example> The present invention will be described in further detail with reference to Examples below. In addition, the bending test in the example was conducted at 65w x 13m from the molded product.
The test was carried out by cutting out a test piece with an oX of 3 mm.

Production Example 1 Production of polyimide-A 4.4-monodiaminodiphenyl ether (DDE) 60
．． 0.7 g (0.3 mol) to 1.200 g N.

Dissolved in N-dimethylacetamide (DMAC) and added 65.44 g of pyromellitic dianhydride (PMDA) (
0.3 mol) was added gradually. After the addition was completed, stirring was continued for an additional hour, and ηnh (in DMAc, concentration 0.
A polyamic acid solution with a value of 2.00 (measured at 5 g/di at 30°C) was obtained.Next, the temperature of this solution was adjusted to 30°C, and 2.80%
0 g of acetone was added to make a homogeneous solution. When 180 g of anhydrous #acid and 200 g of pyridine were added while stirring vigorously, a yellow powder of polyimide precipitated, which was filtered, washed with acetone, and dried at 300°C in nitrogen for 8 hours to form polyimide-A powder ( (hereinafter referred to as P and IA) was obtained.

Production Example 2 Production of Polyimide-B In Production Example 1, PM was used as the tetracarboxylic acid component.
Polyimide-B powder (hereinafter referred to as polyimide-B powder (referred to as PI-B)
I got it.

Production Example 3 Production of Polyimide-C In Production Example 1c, 16.22 g (0.15 mol) of paraphenylene diamine and, as a diamine component,
A mixture of 64.87 g (0.15 mol) of bis[4-(4-aminophenoxy)phenylcosulfone was used, and as a tetracarboxylic acid component, 3.3-, 4.4--
Biphenyltetracarboxylic dianhydride 88.27g (0
Polyimide-C powder (hereinafter referred to as PI-C) was obtained by polymerization in substantially the same manner except that 3 moles of polyimide-C were used.

Example 1.2 and Comparative Example 1.2 PI-A and “Thermid” IP-600 (n=1
, hereinafter referred to as IP) toluene/DMAc=20/1
(Weight ratio) After thoroughly stirring in the mixed solvent to obtain a uniform dispersion, it was placed in a vacuum dryer and dried at 140° C. for 15 hours. Subsequently, it was pulverized using an AICA analytical pulverizer to obtain an aromatic polyimide resin powder composition. When the bulk density of this powder composition was measured, it was 0.352 g/CC. On the other hand, the bulk density of raw material polyimide-A powder is 0.241
g/CC, and the composition of the present invention had an increased bulk density and was a powder that was easy to handle.

Subsequently, this powder composition was put into a mold and heated at room temperature for 30 minutes.
By applying a pressure of Okg f/-, 100
A green compact of tm x 1000 x 3 rmt was molded. Next, this green compact was placed in a nitrogen-substituted oven, and heated for 5 minutes.
The temperature rises from 0℃ to 450℃ in 1 hour, and then further to 450℃
It was heat-treated for 1 hour. After cooling, the molded product was taken out and subjected to a bending test, with the results shown in Table 1.

Table a) Brittle and unmeasurable As can be seen from Table 1, the composition of the present invention has improved moldability and powders are more likely to coalesce.Comparative Example 1
The strength is significantly improved compared to . However, comparative example 2
If the amount added is too large, the toughness of the aromatic polyimide resin will be impaired and it will become brittle, which is not preferable.

Comparative Example 3 In Production Example 1, the drying temperature was set to 160'C to obtain polyimide powder in which amic acid remained.

Using this powder, the same molding as in Comparative Example 1 was carried out, but
There was a lot of gas generated and the molded product cracked, making it impossible to measure its physical properties. Also, in order to prevent cracking, 5
It was found that a heating time of 4 hours or more was required from 0°C to 450°C, and the molding cycle was extremely long compared to the example.

Comparative Example 4 In Example 1, molding was performed using bismaleimide resin powder ("Gelimide" 601 manufactured by Nippon Polyimide) instead of IP. However, this may be due to thermal decomposition during molding.
The molded product is heavily blackened and has a bending strength of 280kf.
It was as low as t/aJ.

Comparative Example 5 In Example 1, molding was performed using an epoxy resin ("Epicoat" 871 manufactured by Yuka Shell Epoxy) instead of IP. However, decomposition and foaming occurred during molding, and physical property tests could not be performed.

Example 3.4 and Comparative Example 6.7 PI-B, PI-C and “Thermid” MC-600 (
Molding and physical property evaluation were carried out in the same manner as in Example 1 using MG (hereinafter referred to as MG).

The results are shown in Table 2, and it was found that the composition of the present invention has improved moldability compared to polyimide powder alone and provides a product with high strength.

Table 2 Example 5 and Comparative Example 8 PI-A55 parts by weight, IP5 parts by weight, i-lead (“CP” made by Nippon Graphite Co., Ltd. > 30 parts by weight, tetrafluoroethylene resin (“Teflon” made by Mitsui DuPont Fluorochemicals) 7-J)10
After tri-blending the parts by weight, molding and physical property evaluation were performed in the same manner as in Example 1. As a result, bending strength/modulus of elasticity = 690/
It was excellent at 42,000 kg f/aA. On the other hand, in Comparative Example 7 without adding IP, the ratio was 260/35.00.
The strength was extremely low at 0 kg f/aJ.

<Effects of the Invention> As is clear from the Examples and Comparative Examples, the composition according to the present invention maintains the heat resistance inherent to aromatic polyimide resin, and has significantly improved moldability. Therefore, high-strength molded products can be molded in a short time.

The polyimide molded product thus obtained has excellent heat resistance,
It has mechanical properties, sliding properties, etc., and is useful for electrical/electronic parts, automobile parts, office equipment parts, space/aircraft parts, etc.

Claims (1)

[Scope of Claims] (A) 99.9 to 50% by weight of an aromatic polyimide resin, and (B) an acetylene-terminated thermosetting polyimide oligomer represented by the general formula ▲ Numerical formula, chemical formula, table, etc. ▼ and/or Or an aromatic polyimide resin composition consisting of 0.1 to 50% by weight of an acetylene-terminated thermosetting polyisoimide oligomer represented by the general formula ▲ Numerical formula, chemical formula, table, etc. ▼. (In the formula, Ar_1 represents a tetravalent aromatic residue, Ar_2 represents a divalent aromatic residue, and n represents an integer from 0 to 30.)