JP2000327881A - Thermosetting resin composition and molding material prepared by using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting resin composition excellent in curability, thermal stability, and strengths by compounding a novolak phenol resin with a hexamethylenetetramine salt of an amic acid oligomer as a curing agent. SOLUTION: This composition is prepared by compounding 100 pts.wt. novolak phenol resin with 7-30 pts.wt. hexamethylenetetramine salt of an amic acid oligomer as a curing agent. The oligomer is synthesized by reacting a tetracarboxylic dianhydride represented by formula II (wherein R1 is an aromatic group) with a diamine represented by formula III (wherein R2 is alkylene or phenylene) and is represented by formula I (wherein n is 4-8), having 4-8 repeating units each having four amide groups (as shown in the parentheses of formula I). A molding material prepared by using this composition can greatly decrease the curing time in the molding step, makes high-cycle molding possible, thus enhancing the productivity, and can give high-quality molded articles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to curability, heat stability,
The present invention relates to a thermosetting resin composition excellent in both strength and a molding material using the same.

[0002]

2. Description of the Related Art Phenolic resin molding materials are widely used in automobile parts, electronic / electric parts, machine parts, kitchen parts, etc. because of their excellent heat resistance, durability, electrical properties, mechanical properties, and cost performance. ing. recent years,
In order to further improve productivity, molding can be performed in a short time,
In addition, there is a demand for the development of a molding material that can produce a molded product having the intended performance. Conventionally, various improvements have been made to phenol resin molding materials in order to shorten the curing time.

For example, a method using a high-ortho novolak having a methylene chain at an ortho-ortho position with respect to a phenolic hydroxyl group, an aliphatic or aromatic amine such as aniline hydrochloride, hydroxylamine hydrochloride, metaaminophenol hydrochloride, etc. There is a method of adding a hydrochloride or the like (for example, JP-A-45-2975). Further, a method of adding an adduct of hexamethylenetetramine and a phenol derivative as a curing agent (JP-A-54-116049) may be mentioned.

However, when these methods are used, the curing time is shortened, but during injection molding, a curing reaction occurs in the plasticizing process in the cylinder, and the thermal stability is significantly reduced. Therefore, there are problems such as a problem that injection molding cannot be performed for a long period of time and characteristics of molded articles such as strength may be lowered.

[0005] One of the methods for reducing costs and improving productivity is to shorten the molding cycle. Thus, development of a thermosetting resin composition having further improved curability while maintaining heat stability has been demanded.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention provides a thermosetting resin composition having excellent curability, heat stability and strength, and a molding material using the same. The purpose is to provide. More specifically, according to the present invention, during injection molding, (a) excellent heat stability in the in-cylinder plasticizing process, (a) good moldability having excellent curability in the in-mold curing process, and,
(C) A high quality molded product can be provided. It is an object of the present invention to provide a thermosetting resin composition having these features and a molding material using the same.

[0007]

That is, the present invention comprises 100 parts by weight of a novolak type phenol resin (a) and four amide groups in parentheses in one molecule represented by the general formula (1) as a curing agent. Salt (b) 7 of amide acid oligomer having 4 to 8 repeating units with hexamethylenetetramine
A thermosetting resin composition containing up to 30 parts by weight as an essential component and a molding material using the same.

[0008]

Embedded image In the formula, R1 represents an aromatic group, R2 represents an alkyl group or a phenyl group, and n represents an integer of 4 to 8.

The thermosetting resin composition of the present invention comprises an amide acid oligomer having 4 to 8 repeating units having 4 amide groups in parentheses per molecule represented by the general formula (1) and hexamethylene By using a salt with tetramine, it has excellent curability and thermal stability, and a molding material using this can obtain a high-quality molded product without affecting properties such as strength.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The novolak-type phenol resin (a) used in the thermosetting resin composition of the present invention is a novolak-type phenol resin synthesized by a usual reaction of phenols and formaldehyde, Hydrogen resin,
Those appropriately modified with dimethoxyparaxylene, dicyclopentadiene or the like can also be used. Examples of the phenols used for synthesizing the novolak type phenol resin include monohydric and polyhydric phenols such as phenol, cresol, xylenol, naphthol, pt-butylphenol, bisphenol A, resorcinol, and one of their substituted products. Or two or more types. On the other hand, as formaldehydes, formalin, paraformaldehyde and the like can be exemplified.

An amic acid oligomer having 4 to 8 repeating units having 4 amide groups in parentheses in one molecule represented by the general formula (1) and hexamethylene used in the thermosetting resin composition of the present invention. The salt with tetramine is in a powder form and is used as a curing agent.

An amide acid oligomer having 4 to 8 repeating units having 4 amide groups in parentheses in one molecule represented by the general formula (1) and hexamethylene used in the thermosetting resin composition of the present invention. The salt with tetramine can be obtained by converting the amide acid oligomer to hexamethylenetetramine in a weight ratio of amide acid oligomer / hexamethylenetetramine of 1/4.
No. 8 to No. 8, the reaction was carried out at room temperature in a polar solvent, and the product was precipitated with alcohol.

The amide acid oligomer used in the thermosetting resin composition of the present invention is obtained by reacting a tetracarboxylic dianhydride represented by the general formula (2) with a diamine represented by the general formula (3). In order to reduce the number of repeating units in parentheses represented by the general formula (1) to 4 to 8,
An acid anhydride as an end cap agent is added to the tetracarboxylic dianhydride in an amount of 4 to 6 phr to control the reaction. Examples of the endcap agent include acid anhydrides such as phthalic anhydride and maleic anhydride.

[0014]

Embedded image In the formula, R1 represents an aromatic group.

[0015]

Embedded image In the formula, R2 represents an alkyl group or a phenyl group.

The tetracarboxylic dianhydride represented by the general formula (2) used in the synthesis of the amide acid oligomer used in the thermosetting resin composition of the present invention includes 3,3 ′, 4
4'-biphenyltetracarboxylic dianhydride (BPD
A), pyromellitic anhydride (PMDA), 3,3 ',
4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and the like.

The diamine represented by the general formula (3) includes 4,4'-oxydianiline (ODA), 2,5
-Dimethyl-p-phenylenediamine, 2,2-bis (4- (4-aminophenoxy) phenyl) propane (BAPP), 4,4'-methylenedianiline (MD
A) and the like.

The reaction between the tetracarboxylic dianhydride and the diamine is carried out by a known method in an aprotic polar solvent. The aprotic polar solvent is N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DM
AC), N-methyl-2-pyrrolidone (NMP), tetrahydrofuran (THF), diglyme, cyclohexanone, 1,4 dioxaan and the like. As the aprotic polar solvent, only one type may be used, or two or more types may be mixed and used.

The reaction between the tetracarboxylic dianhydride and the diamine is carried out by dissolving a well-dried diamine component in the above-mentioned reaction solvent, which has been dehydrated and purified, and thoroughly drying it with a ring closure of 98%, more preferably 99% or more. The reaction is proceeded by adding tetracarboxylic dianhydride.

The amide acid oligomer represented by the general formula (1) is polymerized by reacting tetracarboxylic dianhydride with diamine at an acid / amine equivalent ratio of 0.5 to 0.75. Tetracarboxylic dianhydride / acid with diamine /
When the amine equivalent ratio exceeds 0.75, the amide group in one molecule represented by the general formula (1) exceeds n = 8 and becomes a high molecular weight. The fluidity is poor, a sufficient cross-linking point cannot be obtained in the mold, and the required cured product strength cannot be obtained. In addition, the reaction takes a long time, and improvement in the molding cycle cannot be expected. On the other hand, when the acid / amine equivalent ratio is less than 0.5, n is less than 4 and the fluidity of the salt of the amide acid oligomer and hexamethylenetetramine at the time of molding is good due to the low molecular weight. However, since the reactivity is good, the reaction proceeds during the plasticizing step and the thermal stability is poor. In addition, since the number of reaction points of the salt of the amide acid oligomer and hexamethylenetetramine is small, a sufficient three-dimensional crosslink density cannot be obtained, and the physical properties of the cured product such as strength are reduced.

The thermosetting resin composition of the present invention comprises the novolak phenol resin (a) and 4 to 8 repeating units having four amide groups in parentheses in one molecule represented by the general formula (1). A salt (b) of an amide acid oligomer and hexamethylenetetramine having an amide acid oligomer as an essential component is blended with 100 parts by weight of a novolak-type phenol resin in one molecule represented by the general formula (1). A salt of an amic acid oligomer having 4 to 8 repeating units having 4 groups with hexamethylenetetramine, preferably 7 to
30 parts by weight, more preferably 12 to 20 parts by weight.

Here, the salt (b) acts as a curing agent for the novolak-type phenolic resin (a), and a known acidic catalyst or basic catalyst is used in combination as a catalyst if the thermal stability is not deteriorated. It is also possible. These components can be appropriately added as needed.

In addition to the thermosetting resin composition, a filler can be added to the thermosetting resin molding material of the present invention. Examples of the filler include organic powders such as wood powder, pulp powder, pulverized various woven fabrics, pulverized thermosetting resin cured products and molded products, silica, alumina, aluminum hydroxide, glass, talc, clay, mica, and carbonic acid. Inorganic powders such as calcium and carbon, inorganic fibers such as glass fiber and carbon fiber, and release agents are used, and one or more of these can be used. These fillers can be appropriately added as needed.

The thermosetting resin molding material of the present invention can be obtained by mixing the above components by a general method and kneading the mixture by a known technique such as a hot roll or a kneader.

The thermosetting resin molding material of the present invention is cured at a general molding temperature of 170 ° C. or higher using a molding machine such as an injection molding machine, but can be cured in half the time required by the conventional method. It is excellent in fluidity and thermal stability and can be used for molded products in general.

[0026]

EXAMPLES The present invention will be described below in detail with reference to Examples, but the present invention is not limited thereto.

"Synthesis Example 1" (1) Synthesis of amide acid oligomer Tetracarboxylic acid dianhydride / diamine equivalent ratio 1/2 Dry nitrogen gas inlet tube, cooling tube, thermometer, four-port equipped with a stirrer 1500 g of dehydrated and purified N, N-dimethylformamide (hereinafter abbreviated as DMF) is placed in a flask, and the mixture is vigorously stirred for 10 minutes while flowing nitrogen gas. Next, 2,2-bis (4- (4-aminophenoxy) phenyl) propane (hereinafter abbreviated as BAPP; Mw = 410) 4
Add 10 g (2 equivalents) and stir until uniform. After being uniformly dissolved, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (hereinafter abbreviated as BPDA; Mw =
294) was added over a period of 15 minutes while keeping 147 g (1 equivalent) of powder. Further, 5 phr of phthalic anhydride was added to BPDA, followed by stirring for 3 hours. This solution was poured into a large amount of methanol to confirm a reaction product, and a precipitate was obtained. The precipitate was filtered, vacuum-dried at 60 ° C. for 5 hours, and then pulverized to obtain 500 g of a powdery amic acid oligomer. GPC confirmed that the number of repeating units having four amide groups in parentheses was n = 4 to 8 in one molecule of the amide acid oligomer represented by the general formula (1).

(2) Synthesis of salt of amide acid oligomer and hexamethylenetetramine 50 g of amide acid oligomer obtained above was added to N-methyl-2
After dissolving in 1000 g of pyrrolidone (hereinafter abbreviated as NMP), 300 g of hexamethylenetetramine was added,
After stirring for 30 minutes, the mixture was poured into a large amount of methanol to obtain a precipitate. The precipitate was filtered, dried under vacuum at 60 ° C. for 5 hours, and then pulverized to obtain 315 g of a powdery salt (A).

"Synthesis Example 2" (1) Synthesis of amide acid oligomer Tetracarboxylic dianhydride / diamine equivalent ratio 3/4 Four ports equipped with a dry nitrogen gas inlet tube, a cooling tube, a thermometer, and a stirrer In a flask, 1000 g of dehydrated and purified DMF,
Add 500 g of NMP and stir vigorously for 10 minutes while flowing nitrogen gas. Next, 396 g (4 equivalents) of 4,4′-methylenedianiline (hereinafter abbreviated as MDA; Mw = 198) is charged, and the mixture is stirred until uniform. After dissolving uniformly, 441 g (3 equivalents) of BPDA was added in the form of powder over 15 minutes.
Stirring was continued for 3 hours after the addition of r. This solution was poured into a large amount of methanol to obtain a precipitate. The precipitate is filtered and 6
After vacuum drying at 0 ° C. for 5 hours, the mixture was pulverized to obtain 745 g of a powdery amide acid oligomer. According to GPC, the number of repeating units having four amide groups in parentheses in one molecule of the amide acid oligomer represented by the general formula (1) is n = 4 to
8 was confirmed.

(2) Synthesis of salt of amide acid oligomer and hexamethylenetetramine 75 g of amide acid oligomer obtained above was added to NMP1000
g, and then dissolved in hexamethylenetetramine (450 g).
After stirring for 30 minutes, the mixture was poured into a large amount of methanol to obtain a precipitate. The precipitate was filtered, dried under vacuum at 60 ° C. for 5 hours, and then pulverized to obtain 470 g of a powdery salt (B).

"Synthesis Example 3" (1) Synthesis of amide acid oligomer Tetracarboxylic dianhydride / diamine equivalent ratio 3/5 Four ports equipped with a dry nitrogen gas inlet tube, a cooling tube, a thermometer, and a stirrer 1500 g of dehydrated and purified tetrahydrofuran (hereinafter abbreviated as THF) is placed in a flask and stirred vigorously for 10 minutes while flowing nitrogen gas. Next, BAPP82
Add 0 g (4 equivalents) and stir until uniform.
After uniformly dissolving, 353 g (2.4 equivalents) of BPDA powder was added as it was over 15 minutes, and 5 phr of maleic anhydride was further added to BPDA, followed by stirring for 3 hours. This solution was poured into a large amount of methanol to obtain a precipitate. The precipitate was filtered, dried under vacuum at 60 ° C. for 5 hours, and then pulverized to obtain 1044 g of a powdery amic acid oligomer. GPC confirmed that the number of repeating units having four amide groups in parentheses was n = 4 to 8 in one molecule of the amide acid oligomer represented by the general formula (1).

(2) Synthesis of salt of amide acid oligomer and hexamethylenetetramine 104 g of amide acid oligomer obtained above was added to NMP100
0 g, then hexamethylenetetramine 520
g was added and stirred for 30 minutes, and then poured into a large amount of methanol to obtain a precipitate. The precipitate was filtered, dried under vacuum at 60 ° C. for 5 hours, and then pulverized to obtain 555 g of a powdery salt (C).

"Synthesis Example 4" (1) Synthesis of amide acid oligomer Tetracarboxylic dianhydride / diamine equivalent ratio 1/2 Dry nitrogen gas inlet tube, cooling tube, thermometer, four-port equipped with a stirrer 1500 g of dehydrated and purified THF is placed in the flask and stirred vigorously for 10 minutes while flowing nitrogen gas.
Next, 396 g (4 equivalents) of MDA is charged, and the mixture is stirred until it becomes uniform. After uniformly dissolving, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride (BTDA)
Abbreviated. (Mw = 310) was added over a period of 15 minutes while keeping 310 g (2 equivalents) of the powder, and 6 phr of phthalic anhydride was further added to BTDA, followed by stirring for 3 hours. This solution was poured into a large amount of methanol to obtain a precipitate. The precipitate was filtered, vacuum-dried at 60 ° C. for 5 hours, and then pulverized to obtain 635 g of a powdery amic acid oligomer. According to GPC, the number of repeating units having four amide groups in parentheses in one molecule of the amide acid oligomer represented by the general formula (1) is n
= 4-8.

(2) Synthesis of salt of amide acid oligomer and hexamethylenetetramine 65 g of amide acid oligomer obtained above was added to NMP1000
g, and then dissolve in 390 g of hexamethylenetetramine.
Was added, and the mixture was poured into a large amount of methanol to obtain a precipitate. The precipitate was filtered, dried under vacuum at 60 ° C. for 5 hours, and then pulverized to obtain 410 g of a powdery salt (D).

"Synthesis Example 5" (1) Synthesis of amide acid oligomer Tetracarboxylic dianhydride / diamine equivalent ratio 3/4 Dry nitrogen gas inlet tube, cooling tube, thermometer, four-port equipped with a stirrer 1500 g of dehydrated and purified N, N-dimethylacetamide is placed in a flask, and 10
Stir vigorously for a minute. Next, 800 g (8 equivalents) of 4,4′-oxydianiline (Mw = 200) is charged, and the mixture is stirred until it becomes uniform. After being uniformly dissolved, pyromellitic anhydride (hereinafter abbreviated as PMDA; Mw = 218) was added to 654.
g (6 eq.) powder as it is added over 15 minutes.
After adding 5 phr of phthalic anhydride to MDA, stirring was continued for 3 hours. This solution was poured into a large amount of methanol to obtain a precipitate. The precipitate was filtered, vacuum-dried at 60 ° C. for 5 hours, pulverized, and pulverized to obtain 1310 g of a powdery amic acid oligomer. GPC confirmed that the number of repeating units having four amide groups in parentheses was n = 4 to 8 in one molecule of the amide acid oligomer represented by the general formula (1).

(2) Synthesis of salt of amide acid oligomer and hexamethylenetetramine After dissolving 110 g of the amide acid oligomer obtained above in NMP, 660 g of hexamethylenetetramine was added, and the mixture was poured into a large amount of methanol. A precipitate was obtained. The precipitate was filtered and dried under vacuum at 60 ° C. for 5 hours to obtain 678 g of a powdery salt (E).

Example 1 To 100 g of a novolak type phenol resin (number average molecular weight: 800), 16 g of the salt (A) of the amide acid oligomer obtained in Synthesis Example 1 and hexamethylenetetramine was added, and the mixture was used as a filler. Wood flour 54
g, organic fiber powder 20 g, inorganic powder 20 g and release agent 6 g
And a total of 100 g is kneaded with a heating roll,
A thermosetting resin molding material was obtained. Test pieces were produced from this molding material by injection molding, and various characteristics were evaluated.

Example 2 A salt of the amide acid oligomer and hexamethylenetetramine obtained in Synthesis Example 2 (16 g) was used in place of the amide acid oligomer and hexamethylenetetramine salt (A) 16 g used in Example 1. B) 15
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Example 3 A salt of the amide acid oligomer and hexamethylenetetramine obtained in Synthesis Example 3 (16 g) in place of the salt (A) of the amide acid oligomer and hexamethylenetetramine used in Example 1 was used. C) 12
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Example 4 A salt of the amide acid oligomer obtained in Synthesis Example 4 with hexamethylenetetramine (instead of 16 g of the salt (A) of the amide acid oligomer and hexamethylenetetramine used in Example 1) D) 20
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Example 5 A salt of the amide acid oligomer and hexamethylenetetramine obtained in Synthesis Example 5 (16 g) was used instead of the salt (A) of the amide acid oligomer and hexamethylenetetramine used in Example 1 (16 g). E) 12
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Example 6 A salt of the amide acid oligomer obtained in Synthesis Example 3 with hexamethylenetetramine (instead of 16 g of the salt (A) of the amide acid oligomer and hexamethylenetetramine used in Example 1) C) 30
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Example 7 A salt of an amic acid oligomer obtained in Synthesis Example 2 with hexamethylenetetramine (instead of 16 g of the salt of an amic acid oligomer and hexamethylenetetramine used in Example 1) was used. B) 7g
A thermosetting resin molding material was obtained in the same manner as in Example 1 except for using. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Comparative Example 1 Hexamethylenetetramine 16 was replaced with 16 g of the salt (A) of an amic acid oligomer and hexamethylenetetramine used in Example 1.
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Comparative Example 2 Hexamethylenetetramine 16 was replaced with 16 g of the salt (A) of the amide acid oligomer and hexamethylenetetramine used in Example 1.
g and 8 g of benzoic acid, except that a thermosetting resin molding material was obtained in the same manner as in Example 1. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

"Synthesis Example 6" BAPP4 used in Synthesis Example 1
An amide acid oligomer was synthesized in the same manner as in Synthesis Example 1, except that 205 g (1 equivalent) of BAPP was used instead of 10 g (2 equivalents) (equivalent ratio of tetracarboxylic dianhydride / diamine 1/1). A salt (F) of an amic acid oligomer and hexamethylenetetramine was obtained. By GPC, it was confirmed that the number of repeating units having four amide groups in parentheses was n = 20 to 30 in one molecule of the amide acid oligomer represented by the general formula (1).

Comparative Example 3 A salt of the amide acid oligomer and hexamethylenetetramine obtained in Synthesis Example 6 (16 g) was used instead of the amide acid oligomer and hexamethylenetetramine salt (A) 16 g used in Example 1. F) 16
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

"Synthesis Example 7" MDA39 used in Synthesis Example 2
Instead of 6 g (4 equivalents) and 441 g of BPDA (3 equivalents), 495 g (5 equivalents) of MDA and 294 g of BPDA (2 equivalents)
(Equivalent) and (tetracarboxylic dianhydride / diamine)
Except for the equivalent ratio of 2/5), an amic acid oligomer was synthesized in the same manner as in Synthesis Example 1, and a salt (G) of the amic acid oligomer and hexamethylenetetramine was obtained. GPC
Of the amide acid oligomer represented by the general formula (1)
It was confirmed that the number of repeating units having four amide groups in parentheses in one molecule was n = 2 to 3.

Comparative Example 4 A salt of the amide acid oligomer obtained in Synthesis Example 7 with hexamethylenetetramine (instead of 16 g of the salt (A) of the amide acid oligomer and hexamethylenetetramine used in Example 1) G) 15
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Comparative Example 5 Hexamethylenetetramine 16 was replaced with 16 g of the salt (A) of an amic acid oligomer and hexamethylenetetramine used in Example 1.
g and salicylic acid 6.6 g were used in the same manner as in Example 1 to obtain a thermosetting resin molding material. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Comparative Example 6 Hexamethylenetetramine 16 was replaced with 16 g of the salt (A) of the amide acid oligomer and hexamethylenetetramine used in Example 1.
g and a thermosetting resin molding material were obtained in the same manner as in Example 1 except for using 5.3 g of methylolphenol.
Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Comparative Example 7 A salt of the amide acid oligomer and hexamethylenetetramine obtained in Synthesis Example 4 (16 g) was used instead of the amide acid oligomer and hexamethylenetetramine salt (A) 16 g used in Example 1. D) 4g
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

Comparative Example 8 A salt of the amide acid oligomer obtained in Synthesis Example 4 with hexamethylenetetramine (instead of 16 g of the salt of the amide acid oligomer and hexamethylenetetramine used in Example 1) was used. D) 35
A thermosetting resin molding material was obtained in the same manner as in Example 1 except that g was used. Test pieces were prepared from this molding material by injection molding, and various characteristics were evaluated.

The curability, thermal stability, and cured product characteristics of the molding materials obtained in each of the Examples and Comparative Examples were measured by the following methods.

(1) Evaluation of Curability The composition was cured by injection molding at 175 ° C. for 15 seconds, 25 seconds, and 40 seconds, and then the test piece was removed from the mold.
After 10 seconds, the surface hardness of the test piece was measured using a Barcol hardness meter 935. (2) Flexural strength Cured by injection molding at 175 ° C for 180 seconds, JIS K
The bending strength was measured according to 6911. (3) Evaluation of thermal stability The thermal stability was evaluated by comparing the stability duration at 100 ° C. using Toyo Seiki Labo Plastmill.

Table 1 shows the characteristics obtained in Examples 1 to 7 and Comparative Examples 1 to 8.

[0057]

[Table 1]

From Table 1, it can be seen that when molded using the molding materials obtained in Examples 1 to 7, both the curability and the thermal stability are good. Comparative Examples 1 to 7 have good thermal stability but poor curability, and Comparative Example 8 has good curability but poor thermal stability. Comparative Examples have a balance between curability and thermal stability. Missing. When the bending strength is observed, the strength tends to decrease when an acid component is added as in Comparative Examples 2 and 5, but when a salt of an amide acid oligomer and hexamethylenetetramine is used, the bending strength is large. No decrease is seen.

[0059]

The thermosetting resin composition of the present invention and the molding material using the same have extremely excellent curability without deteriorating the properties of the cured product such as strength, and also have a good thermal stability. Are better. By using the thermosetting resin composition of the present invention and a molding material using the same, the curing time at the time of molding can be significantly reduced, the molding cycle can be increased, and productivity can be improved. Can be done, and
High quality molded products can be obtained.

Claims (3)

[Claims] 1. A novolak type phenol resin (a) 10
A thermosetting resin composition comprising, as an essential component, 0 to 30 parts by weight of a salt (b) of an amide acid oligomer represented by the general formula (1) and hexamethylenetetramine (b). Embedded image However, in the general formula (1), R1 represents an aromatic group, R2 represents an alkyl group or a phenyl group, and n represents an integer of 4 to 8. 2. The amide acid oligomer is synthesized by reacting a tetracarboxylic dianhydride represented by the general formula (2) with a diamine represented by the general formula (3). The thermosetting resin composition according to the above. Embedded image However, in the general formula (2), R1 represents an aromatic group. Embedded image However, in the general formula (3), R2 represents an alkyl group or a phenyl group. 3. A molding material using the thermosetting resin composition according to claim 1.