JPH08165429A - Heat resistant resin composition - Google Patents

Abstract

PURPOSE: To obtain a heat resistant resin composition containing each specific polyimide, a novolak and a resol, capable of exhibiting good physical properties, moldability, and heat resistances and useful for a molding material, etc. CONSTITUTION: This heat resistant resin composition comprises containing (A) a polyimide having phenolic hydroxy groups in a molecule (e.g. compound of the formula) obtained by reacting three components of (i) a sulfanilamide, (ii) a bismaleimide (e.g. N, N'-diphenylmethanebismaleimide), (iii) aminophenols having an amino group and a phenolic hydroxy group simultaneously (e.g. paraaminophenol), (B) a novolak and (C) a resol obtained by reacting phenols with aldehydes under an alkali catalyst. Moreover, the composition preferably contains 30-70 pts.wt. component (A) and 70-20 pts.wt. mixture of (B) and (C) [10-70wt.% component (B) and 30-90wt.% component (C)].

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a heat resistant resin composition. More specifically, the present invention relates to a heat-resistant resin composition that is curable, exhibits good physical properties and heat resistance, and is useful in various fields such as molding materials, laminated plates, grindstones and brakes.

[0002]

2. Description of the Related Art As the demand for the plastics industry increases, resins with various physical properties are required in various fields, and heat-resistant resins are one of them. . Heretofore, many heat resistant resins have been proposed. For example, a heat-resistant resin obtained by reacting bismaleimide with an aromatic diamine is known, but it requires high temperature and long time for curing, and the product form is mainly liquid (solvent solution). An object of the present invention is to provide a heat resistant resin composition which is excellent not only in heat resistance but also in moldability and physical properties.

[0003]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to obtain resins having excellent heat resistance and moldability, mainly for applications using powder resins. As a result, sulfanilamide and bismaleimide, In addition, by reacting aminophenols that share an amino group and a phenolic hydroxyl group in one molecule as a third component, a polyimide having a phenolic hydroxyl group at the end is synthesized, and by using this together with novolac and resol. The inventors have found that the above objects can be achieved and completed the present invention.

That is, the present invention reacts three components: [a] (1) sulfanilamide; (2) bismaleimide; and (3) aminophenols sharing an amino group and a phenolic hydroxyl group in one molecule. A heat-resistant resin containing a polyimide having a phenolic hydroxyl group in the molecule, [b] novolac, and a resol obtained by reacting [c] a phenol and an aldehyde under an alkaline catalyst. A composition is provided.

The present invention also provides [a] polyimides 10-9.
There is provided a composition as described above, which comprises 0 parts by weight and 90 to 10 parts by weight of a mixture of [b] novolac and [c] resole.

The present invention further relates to [a] polyimide 30-
There is provided a composition as described above, which comprises 70 parts by weight and 70 to 30 parts by weight of a mixture of [b] novolac and [c] resole.

Still further, the invention provides that the mixture comprises 10-70% by weight of [b] novolac and 30- [c] resol.
It provides 90% by weight of the above composition.

The present invention will be described in more detail below. [A] Polyimide The polyimide which is one component of the composition of the present invention is obtained by reacting the components (1), (2) and (3) as described above. Hereinafter, each component will be described. (1) Sulfanilamide Sulfanilamide is represented by the following chemical formula.

[0009]

Embedded image

(2) Bismaleimide Bismaleimide is a compound having two maleimide groups in the molecule, and various kinds can be used in the present invention. Specifically, N, N'-diphenylmethane bismaleimide, N, N'-diphenyl ether bismaleimide, N, N'-paraphenylene bismaleimide, N, N '-(2-methylmetaphenylene) bismaleimide, N, N'-metaphenylene bismaleimide, N, N '
Examples thereof include-(3,3-dimethyldiphenylmethane) bismaleimide and N, N '-(3,3-diphenylsulfone) bismaleimide, with N, N'-diphenylmethane bismaleimide being preferred.

(3) Aminophenols Sharing an Amino Group and a Phenolic Hydroxyl Group in One Molecule The above-mentioned aminophenols may be appropriately selected from various types. Specifically, para-aminophenol , Ortho-aminophenol, 4-amino-4′-hydroxyphenylpropane, etc., and para-aminophenol is superior in terms of availability, cost, and other practical properties.

The reaction of the above components (1), (2) and (3) can be carried out by a known method. For example, a method of melting and mixing the components and maintaining the reaction at an appropriate temperature may be used. Further, the reaction of each component can be carried out in an organic solvent, for example, in a dimethylformamide solution. The use ratios of the above-mentioned components (1), (2) and (3) are different depending on the required physical properties of the composition. For example, relative to 1 mol of the aminophenols of the component (3), 3 to 30 mol of each of the components 1) and (2) is suitable.

In this way, the polyimide [a] is synthesized. This [a] polyimide can be represented by the following formula (note that this is an example in which N, N′-diphenylmethane bismaleimide is used as the bismaleimide and para-aminophenol is used as the aminophenol).

[0014]

Embedded image

The model of the cured resin obtained by reacting the [a] polyimide of the above formula with [b] novolac and [c] resole is as follows.

[0016]

Embedded image

[B] Novolac Novolak, which is one component of the composition of the present invention, means one obtained by condensing phenols and aldehydes under an acidic catalyst. As the novolak, various kinds can be used, but preferably, it is better to be reactive with the methylol group of the resole, and trifunctional or higher functional phenols and aldehydes are used as an acid catalyst such as oxalic acid or sulfuric acid. Which has a melting point of 60 to 150 ° C., preferably 80 to 120 ° C. and a molecular weight of about 300 to 1,500, preferably 500 to 1,000.
Furthermore, it is desirable that the novolac has a type containing as little free phenol as possible. Examples of trifunctional or higher phenols include phenol, m-cresol, and 3,5-
Examples include xylenol, resorcin, hydroquinone, bisphenol A, bisphenol F, and biphenol, and these can be used as a mixture of two or more kinds. Examples of the aldehydes include formaldehyde, paraformaldehyde, polyoxymethylene, trioxane and the like. As such a novolac, a commercially available one can be used. For example, Showa High Polymer Co., Ltd. trade name Shonor BRG-558 (obtained by reacting phenol and formaldehyde using oxalic acid as a catalyst, free phenol 0.1% by weight or less, molecular weight about 500, melting point about 60 ° C. And the like).

One of the roles of this novolak is to react with the methylol group of the resole and introduce it into the polymer through a heat-resistant methylene bond. An example of this reaction mechanism is shown below.

[0019]

[Chemical 4]

Another role is to minimize the formation of methylene ether bond, which has poor heat resistance and is formed by the reaction between resols. For reference, an example of a reaction compound of resoles having a methylene ether bond is shown below.

[0021]

Embedded image

[C] Resol Resol, which is one component of the composition of the present invention, is obtained by reacting phenols and aldehydes under an alkaline catalyst. That is, resols are generally alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, calcium hydroxide and barium hydroxide, alkaline earth metal hydroxides, or alkaline catalysts such as ammonia, tertiary amines and quaternary ammonium. It is obtained by reacting phenols (including polyphenols) with aldehydes (generally, formalin which is an aqueous solution of formaldehyde) in the presence.

Examples of the phenols used for producing the above resole include phenol, cresol, xylenol, resorcin, hydroquinone, te.
Examples thereof include rt-butylphenol, phenylphenol, biphenol, bisphenol A, bisphenol F and bisphenol S. Of these, trifunctional or higher compounds are preferable. More preferably, bisphenol F is preferable from the viewpoints of handleability, price and physical properties. These can be used alone or as a mixture of two or more kinds.

Examples of aldehydes include formaldehyde, paraformaldehyde, polyoxymethylene, trioxane and the like.

In the [c] resole, the ratio of phenols and aldehydes to be used is generally equimolar or the aldehydes can be used in excess.

The production method for producing the resol is not particularly limited. For example, when phenol is used as the phenol, 1.5 mol to 3 mol of formaldehyde to 1 mol of phenol, and further bisphenol F as the phenol is used. In the case of using, a method of reacting 3 or 4 mol of formaldehyde with 1 mol of bisphenol F can be mentioned. In addition, in the present invention, commercially available resol can also be preferably used, for example, Shownor BRN-21 manufactured by Showa High Polymer Co., Ltd.
20 (obtained by reacting phenol and formaldehyde in the presence of an alkali metal catalyst) and the like. Further, as the resol, a liquid or a concentrated product thereof, or a solid product partially reacted with methylol can also be used (for example, Shownor Polymer Co., Ltd., trade name Shonor BLS-455N, bisphenol F).
Tetramethylol compound, solid content of about 75%, ethyl acetate solution).

Blending Ratio The blending ratios of the above-mentioned [a] polyimide, [b] novolac and [c] resole of the composition of the present invention are specified below. [A] 10 to 90 parts by weight of polyimide; and [b] 90 to 10 parts by weight of a mixture of novolac and [c] resole. More preferably, 30 to 70 parts by weight of [a] polyimide and 70 to 30 parts by weight of a mixture of [b] novolac and [c] resole are preferable. When the blending ratio of the mixture of [b] novolac and [c] resole is less than 10 parts by weight, it becomes difficult to form a crosslinked structure and it becomes difficult to exhibit sufficient heat resistance. However, it is not preferable because it may lack long-term heat resistance and toughness.

Here, the blending ratio of each component in the mixture of [b] novolak and [c] resole is 10 to 70% by weight of [b] novolak and 30 to 90 [c] resole, relative to the weight of the mixture. Weight% is good. More preferably, [b] 20 to 60% by weight and [c] 40 to 8
0 wt% is good.

The physical properties of the composition of the present invention are as follows: (1) sulfanilamide, (2) bismaleimide, and (3) aminophenols, and [b] novolak within the above range. And [c]
The composition of the present invention varies greatly depending on the type of resole and the ratio of use, and thus the composition of the present invention can be used for various purposes. For example, if the proportion of resole used is large, the curability becomes quick, but the long-term heat resistance tends to be poor, and the use of a large amount of novolak impairs the curability.

The method for producing the composition of the present invention includes:
It is also possible to simply mix [a] polyimide, [b] novolac, and [c] resole. Apart from this, [a]
It can also be obtained by heating or kneading at a temperature at which polyimide is not completely crosslinked with [b] novolac and [c] resole. However, in the case of using the powder resin, the latter method is preferable because it is easy to handle and has good moldability.

In the above method of heating or kneading at a temperature at which the polyimide [a] is not completely crosslinked with the novolac [b] and the resole [c], the temperature at the time of heating or kneading is 80 to 130 ° C. Is preferred. By heating or kneading by heating, the polyimide, the novolac and the resole are partially reacted to obtain a composition having a required softening point and heat fluidity and good moldability.

Molding of the composition of the present invention is carried out, for example, at a temperature of 150 to 200 ° C. and a temperature of 50 to 200 in the same manner as a general phenol resin.
It can be carried out under a pressure of 200 kg / cm ² .

In the practical use of the composition of the present invention, it is needless to say that an organic or inorganic filler, a fiber reinforcing material, a release agent, a colorant, a thermoplastic polymer, a coupling agent and the like can be used in combination.

[0034]

The composition of the present invention exhibits excellent heat resistance that combines the long-term heat resistance of polyimide, the antioxidant action of the resole, and the resistance to short-term temperature rise.

[0035]

The present invention will be described below with reference to examples. Example 1 A 1-liter 4-neck separable flask equipped with a stirrer, a reflux condenser, and a thermometer was charged with sulfanilamide 1
55 g, para-aminophenol 22 g, phenothiazine 0.5 g, N, N'-diphenylmethane bismaleimide 3
58 g was charged and reacted at 170 to 180 ° C. for 2 hours. A polyimide (a) having a phenolic hydroxyl group at the end was obtained with a dark brown color and a melting point of 140 to 150 ° C.

Next, as a novolac, Shownor Polymer Co., Ltd. Shownol BRG-558 (free phenol amount 0.1% by weight or less, phenolic), and as a resol, Showa Polymer Ltd. Shownol BLS-455N (bisphenol F). Of tetramethylol, solid content of about 75%, and ethyl acetate solution), in the mixing ratio of Table 1 below, 1
The mixture was kneaded for about 6 minutes using a hot roll at 10 to 120 ° C. and pulverized to obtain a molding material (A).

[0037]

[Table 1] Polyimide (a) 100 parts by weight Novolac (BRG-558) 40 parts by weight Resol (BLS-455N) (solid content) 60 parts by weight Milled fiber 400 parts by weight Zinc stearate 6 parts by weight

The molding material (A) was molded at a molding temperature of 170 to 17
A test piece is molded by heating and pressing at 5 ° C and a molding pressure of 70 kg / cm ² for 5 minutes, and at 150 ° C for 12 hours, further 180
After post-curing at 6 ° C. for 6 hours, the physical properties were measured according to JIS K-6911. The results obtained were excellent as shown in Table 2.

[0039]

[Table 2] Bending strength (kg / mm ² ) 18.8 Bending elastic modulus (kg / mm ² ) 1680 Heat distortion temperature (° C) 250 or more Charpy impact value (kg · cm / cm ² ) 14.1 Hardness ( Barcol 934-1) 74 90% weight retention rate temperature (° C) 404 500 ° C weight retention rate (%) 73

Example 2 A composition of 1 mol of phenol, 2 mol of formaldehyde and 0.2 mol of ammonia was reacted at 80 ° C., then decompressed at about 100 ° C., dehydrated and concentrated to proceed to a softening point of 55-60 ° C. , Resol was obtained and used in this Example 2. Using the polyimide (a) used in Example 1, by roll kneading at 110 to 120 ° C. in the compounding ratios shown in Table 3 below,
A molding material (B) was manufactured under the same conditions as in Example 1.

[0041]

[Table 3] Polyimide (a) 120 parts by weight Resol 60 parts by weight Novolac (BRG-558) 20 parts by weight Milled fiber 400 parts by weight Zinc stearate 6 parts by weight

The molding material (B) was molded at a molding temperature of 170 to 17
A test piece was molded by heating and pressurizing at 5 ° C. and a molding pressure of 70 g / cm ² for 5 minutes. Subsequently, post-curing was performed at 150 ° C. for 12 hours and then at 180 ° C. for 6 hours. Table 4 shows the physical properties of the obtained molded product.

[0043]

[Table 4] Bending strength (kg / mm ² ) 16.9 Bending elastic modulus (kg / mm ² ) 1740 Heat deformation temperature (° C) 240 Charpy impact value (kg · cm / cm ² ) 11.4 Hardness (Barcol) 934-1) 76 90% weight retention rate temperature (° C) 401 500 ° C weight retention rate (%) 73

For reference, FIG. 1 shows the measurement results of thermal equipment analysis (TMA) of the molding material (B) obtained in Example 2. It can be seen from FIG. 1 that the molding material (B) has a high glass transition point, and therefore has good heat resistance and excellent mechanical properties.

[0045]

According to the present invention, good physical properties, moldability,
Provided is a heat resistant resin composition which exhibits heat resistance and is useful in various fields such as molding materials, laminated plates, grindstones and brakes.

[Brief description of drawings]

FIG. 1 is a diagram showing a measurement result of TMA of a molding material obtained in Example 2.

Claims (4)

[Claims] 1. Obtained by reacting three components: [a] (1) sulfanilamide; (2) bismaleimide; and (3) aminophenols sharing an amino group and a phenolic hydroxyl group in one molecule. A heat-resistant resin composition containing a polyimide having a phenolic hydroxyl group in the molecule, [b] novolac, and [c] a resole obtained by reacting a phenol with an aldehyde under an alkaline catalyst. 2. A mixture of 10 to 90 parts by weight of [a] polyimide and 90 to 90 parts by weight of [b] novolac and [c] resole.
The composition according to claim 1, which comprises 10 parts by weight. 3. [A] 30 to 70 parts by weight of polyimide and [b] a mixture of novolac and [c] resole 70 to 70 parts by weight.
The composition according to claim 1, which comprises 30 parts by weight. 4. The mixture comprises [b] novolak 10-70.
Composition according to claim 2 or 3, consisting of 30% to 90% by weight of [c] resole.