JPH02258868A - Curable resin composition - Google Patents

Abstract

PURPOSE:To obtain capable of enhancing mechanical strength at high temperature without impairing excellent properties such as electric characteristics and improved in curing properties and processability by blending a specific aromatic polyamide oligomer with a maleimide derivative at a specific amount. CONSTITUTION:(A) 100 pts.wt. aromatic polyamide oligomer expressed by the formula (A is radical polymerizable unsaturated groups; R is H, lower alkyl, etc.; R1 and R2 are bivalent aromatic group; n is 0-15) and having terminal aliphatic unsaturated groups is blended with (B) 10-200 pts.wt., preferably 10-100 pts.wt. maleimide derivatives which are one or more kind of phenylmaleimide, aromatic dimaleimide and aromatic polyamide.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a heat-resistant synthetic resin, particularly to a heat-resistant thermosetting resin composition with excellent processability.

[Prior Art] As the demands of the plastics industry become more sophisticated, industrial materials with special properties are required, and this trend is rapidly developing as technology becomes more sophisticated.

The demand for improved heat resistance is felt in plastics, films, fibers,
The aim is to add heat resistance to industrial materials in fields that require heat resistance, such as laminates, laminates, and adhesives, expand the market, and expand into a wide range of new fields with new functions.

In response to these demands, a group of synthetic resins called engineering plastics, such as aromatic polyamides, polyimides, polysulfones, and polyphenylene oxides, have already been developed, and are being used as plastics with new functions different from conventional synthetic resins. Aromatic polyamides, known under the name aramid, are one of them, being industrially produced and opening up new areas of demand.

Typical aromatic polyamides include polyparaphenylene terephthalamide (trade name: Kevlar) and polymetaphenylene isophthalamide (trade name: Conomex or HT-1) developed by Du Bont.

All of these polyamides are classified as thermoplastic synthetic resins, and a type of polyamide that thermosets oligomers has not yet been found.

For this reason, although it has a higher melting point than ordinary thermoplastic synthetic resins, it is inevitable that hardness, strength, etc. will decrease as the temperature rises, and it is virtually impossible to use it above the softening point. It was possible.

The reason why there was no thermosetting aromatic polyamide was as follows.
- This is thought to be because the melting point of the thermoplastic synthetic resin was sufficiently higher than that of conventional thermoplastic synthetic resins, and the introduction of unsaturated bonds was considered to have a high risk of causing undesirable gelation during the molding process.

On the other hand, it is also well known that one of the typical heat-resistant resins is a polymer formed by adding amino groups to unsaturated bonds in the Michael reaction of simalimides and aromatic diamines ( "Kelimide" by France Rhône-Bouland).

However, when attempting to homopolymerize maleimides, the polymerization reaction is too vigorous at high temperatures, making it impossible to obtain useful polymers.

[Problems to be solved by the invention] Aromatic polyamides are relatively stable even at very high temperatures, have excellent electrical properties and mechanical strength, and are highly chemically stable and are excellent heat-resistant polymers. be.

The present invention aims to further improve mechanical strength and chemical stability at high temperatures without losing these properties.

[Means for solving the problem of 5 layers] The present inventors have developed an interlocking material to be used as a molding material or as a laminate, which has a relatively low melting point and can be molded into a desired shape under heat and pressure. In order to obtain an aromatic lyamide oligomer that can be cured under relatively mild conditions and has sufficient heat resistance, mechanical strength, chemical stability, etc., an aliphatic monoamine having a terminal unsaturated group and an aromatic The group dicarboxylic acid cybalide and optionally an aromatic diamine are reacted in the presence of a hydrogen halide acceptor to obtain an unsaturated polyamide oligomer having a terminal unsaturated group, which can be reacted in the presence of a radical generating catalyst 'F. It has been found that this cured aromatic polyamide has the above-mentioned excellent properties. Furthermore, by using a maleimide in addition to this oligomer, the curing speed can be improved, and the composition of both can be improved. We were able to complete the present invention knowing that the melting point can be lowered by selecting a suitable material, and that this desirable improvement can be achieved.

The aromatic polyamide oligomer having a terminal unsaturated group according to the present invention can be illustrated by the following reaction formula.

(Margin below) (Aromatic dicarboxylic acid cybalide) (Aromatic polyamide oligomer) To allow the reaction in [11] to proceed smoothly.

A acceptor for the by-product hydrogen chloride is required and it is generally convenient to use an aliphatic tertiary amine or a caustic alkali.

In this case, n is about 0 to 15 (however, when n=0, aromatic diamine is not used), preferably 3 to 7.
This value is advantageous from the viewpoint of ease of moldability, and polymerization at this stage is not particularly necessary.

This reaction is generally performed by mixing amines in an aqueous phase and acid chloride in an inert organic solvent that does not dissolve in water to perform an interfacial polycondensation reaction, or by dissolving both in an inert organic solvent and condensing them at low temperatures. This can be carried out by a low-temperature solution polycondensation reaction.

Examples of aliphatic monoamines having a terminal unsaturated group that can be used in the present invention include allylamine, diallylamine, methalylamine, allylmethylamine, and l-amino-4-pentene. is the most commonly used. Note that this amine may be a free amine or a hydrohalide salt, but in the case of a hydrohalide salt, it is necessary to use a tertiary amine etc. that binds to the hydrogen halide at the same time. becomes.

Hereinafter, the aliphatic amine having a terminal unsaturated group will be explained using allylamine as a representative.

Further, as the aromatic dicarboxylic acid civalide that can be used in the present invention, dichlorides of aromatic dibasic acids are convenient, and typical examples include terephthalic acid dichloride, isophthalic acid dichloride, and phthalic acid dichloride.

From a practical point of view, phthalic acid dichloride has insufficient heat resistance as aramid after curing, and terephthalic acid dichloride has sufficient heat resistance, but the resulting aromatic polyamide oligomer has a high melting point. Therefore, isophthalic acid dichloride best meets the purpose of the present invention.

This synthesis reaction proceeds relatively stoichiometrically, so after calculating n in the formula Often, if precise adjustment is required, the molar ratio can be determined by a simple test.

Examples of aromatic diamines include metaphenylenediamine and 4,4'-diaminodiphenylmethane.

4.4°-diaminodiphenylpropane, 3.3'-
Dimethyl-4,4′-diaminodiphenylmethane, 4.
4'-diaminodiphenyl ether, 3.4'-diaminodiphenyl ether, 3,3°-diaminodiphenylsulfone, 4.4"-diaminodiphenylsulfone,
dianisidine, 2.4-) lylene diamine, 2
．． A mixture of 4/2.6-1 lylene diamine and the like can be used, and a mixture of two or more types can also be used.

As described above, the aromatic polyamide oligomer obtained by this reaction can be easily selected in composition and can be molded at a temperature of 200° C. or lower.

The aromatic polyamide oligomer having unsaturated end groups synthesized according to the present invention can be cured in combination with a radical-generating catalyst, making it possible to significantly improve heat resistance. 6. Use in combination with aromatic polyamide oligomer Maleimides can be divided into three types:

(il Phenylmaleimide (iil) The types of simalimide aromatic diamines synthesized from aromatic diamine and maleic anhydride are those mentioned above.

(iii) A polymaleimide synthesized from an aniline-formaldehyde condensate and maleic anhydride. Furthermore, it is also possible to use a mixture of (il, (iil, and (iii)).

Phenylmaleimide has a low melting point and has wide compatibility with aromatic polyamide oligomers, but it also has a slight lack of heat resistance, so simalemides made from aromatic diamines are used as a material.

Examples of these include N-phenylmaleimide, N-(
0-chlorophenyl)maleimide, N,N'-diphenylmethane bismaleimide.

N, N'-diphenyl ether bismaleimide, N,
No-bara phenylene bismaleimide, N.

N'-(2-methylmetaphenylene)bismaleimide, N,N'-metaphenylenebismaleimide, N,
Examples include N'-(3,3'-dimethyldiphenylmethane)bismaleimide, N,N'-(:1.3°-diphenylsulfone)bismaleimide, and maleimides of aniline-formaldehyde condensates.

The aromatic polyamide oligomer (including phthalamide such as diallylisophthalamide) having an unsaturated group at the terminal of the present invention generally has a slow curing speed, and even if a radical generator is used as a catalyst, it cannot be heated to a high temperature for a long time. However, by incorporating a maleimide derivative, the curing speed can be improved.

Furthermore, it has the effect of improving the moldability (lowering the melting point) of the composition containing maleimide before curing, and has the effect of making it possible to process it at low pressure.

The blending ratio of the aromatic polyamide oligomer and the maleimide derivative is 10 to 200 parts by weight, preferably 10 to 1 part by weight, of the maleimide derivative per 100 parts of the aromatic polyamide oligomer.
00 parts by weight.

When the amount of maleimide added is 10 parts by weight or less, heat resistance is good, but the melting point decreases so much that the effect of improving moldability is reduced. In addition, even if the amount exceeds 200 parts by weight, the melting point remains almost constant, and not only is no further drop in the melting point observed, but also the heat resistance decreases, and at the same time, the polymerization reaction becomes more intense and becomes uncontrollable. There is.

The mixture of aromatic polyamide oligomer and maleimide according to the present invention can be cured in combination with a radical-generating catalyst, making it possible to significantly improve heat resistance.

There is no need to limit the radical-generating propellant, but when the molding temperature is 100° C. or higher, a so-called high-temperature decomposition type, for example a dicumyl peroxide type, is used.

The appropriate amount to use is 1 to 3 phr.

In addition, the combined use of monomers copolymerizable with unsaturated bonds is possible when the monomer dissolves aromatic polyamide oligomers and maleimide derivatives, and the scope of application is particularly limited when n in the above formula [I] is a small value. is wide.

It goes without saying that the aromatic polyamide oligomer having unsaturated end groups according to the present invention can be used in combination with reinforcing agents, fillers, mold release agents, colorants, polymers, etc., as necessary, during curing.

Next, examples will be shown below to help understand the present invention.

[Example 1 (Synthesis Example 1) Synthesis of diallylisophthalamide 22.8 g of allylamine was placed in 12 four-necked separable flasks equipped with a reflux condenser, a dropping funnel, 5 thermometers, and a stirrer.
(0.4 mol) and triethylamine 40.4 g (0
, 4 mol) and 200 g of methylene chloride,
Cool to below 0°C.

Next, 40.6 g (0.2 mol) of isophthalic acid chloride was dissolved in 200 g of methylene chloride, and after 0 dropwise addition was completed, stirring was continued for 1 hour. Meanwhile, the temperature of the reaction mixture is maintained below 10°C. Thereafter, the reaction is continued for an additional 5 hours at room temperature.

After the reaction is completed, the reaction mixture is washed several times with water to remove the generated hydrochloride.The reaction mixture washed with water is concentrated to precipitate crystals. The precipitated crystals are suction filtered and dried.

m, p, 125-130°C (Synthesis Example 2) (Oligomer rI) 20.3 g of isophthalic acid chloride was placed in a lβ four-neck separable flask equipped with a reflux condenser, dropping funnel, thermometer, and stirrer. (0', 1 mol).

Charge DMFloog and cool to below 10°C.

Next, 3.4°-diaminodiphenyl ether 16.7
g (0,0835 mol), triethylamine 16.8
Weigh 7g (0,167 mol) and 75g of DMF ffi?
Combine and drop into a separable flask. Subsequently, 1.9 g (0,033 mol) of allylamine, 3.33 g (0,033 mol) of triethylamine, and 25 g of DMF were weighed, mixed, and added dropwise.

During this time, the temperature of the reaction mixture is kept below 10°C.

After the dropwise addition is completed, stirring is continued at the same temperature for 2 hours.

The reaction mixture is then gradually added to vigorously stirred water to allow crystals to precipitate. The precipitated crystals are filtered by suction,
Dry after washing with water.

m, p, 185-195°C (blank below) (Synthesis Example 3) (Oligomer [+11) Isophthalic acid was placed in 12 four-necked separable flasks equipped with a reflux condenser, dropping funnel, thermometer, and stirrer. 20.3 g (0.1 mol) of chloride and DMFloog were charged and cooled to below 10°C.

Next, 3,3′-dimethyldiaminodiphenylmethane 1
1 3g (0.05 mol), triethylamine 10.
1 g (0.1 mol) and 50 g of DMF were weighed and mixed and added dropwise to a separable flask. Next, allylamine 5.
7g (0.1 mol), triethylamine 10.1g
(0.1 mol) and 50 g of DMF were mixed and added dropwise to the reaction flask. During this time, the temperature of the reaction mixture is kept below 10°C.

After the dropwise addition is completed, stirring is continued at the same temperature for 2 hours.

The reaction mixture is then gradually added to vigorously stirred water to allow crystals to precipitate. The precipitated crystals are filtered by suction,
Dry after washing with water.

m, p, 155-160°C (Example 1) 1 part by weight of diallylisophthalamide, 1 part by weight of N-phenylmaleimide, and 2 parts by weight of a 2% acetone solution of dicumyl peroxide were added to a test tube, and heated to 90°C oil. The mixture was placed in a bath and the acetone was evaporated to dryness. The mixture was then a yellow homogeneous solution. When this yellow homogeneous solution was heated to 120° C. and heated for 3 hours, a strong bulky polymer with a pale amber color was obtained.

This polymer was further after-cured at 200°C for 5 hours. The obtained polymer was crushed in a mortar and subjected to thermogravimetric analysis at a heating rate of 10° C./min in air, resulting in the result as shown in (1) in FIG.

(Example 2) N, N' in place of N-phenylmaleimide in Example 1
- Same as Example 1 except that 1 part by weight of diphenylmethane bismaleimide was used.

The resulting polymer was crushed in a mortar and subjected to thermogravimetric analysis at a heating rate of 10°C/min in air, resulting in the result as shown in (2) in Figure 1.

(Example 3) Oligomer [I] synthesized in Synthesis Example 2 1 part by weight, N-
1 part by weight of phenylmaleimide and 2 parts by weight of a 2% acetone solution of dicumyl peroxide were added into the test tube, mixed uniformly, and placed in an oil bath at 90°C to evaporate the acetone and dry. The mixture was then a slightly cloudy yellow homogeneous solution. When this yellow homogeneous solution was heated to 120° C. and heated for 3 hours, an amber-colored, strong, lumpy polymer was obtained. This polymer was further after-cured at 200°C for 5 hours.

The resulting polymer was crushed in a mortar and subjected to thermogravimetric analysis at a heating rate of 10°C/min in air, resulting in the result as shown in (3) in Figure 1.

(Example 4) Oligomer [I] synthesized in Synthesis Example 2 1°894g
(0,001 mol), N-phenylmaleimide 0.17
The same operation as in Example 3 was performed except that 3 g (0,001 mol) and 2.067 g of a 2% acetone solution of dicumyl peroxide were added to the test tube and mixed uniformly.

The resulting polymer was crushed in a mortar and subjected to thermogravimetric analysis at a heating rate of 10° C./min in air, resulting in the result as shown in (4) in FIG.

(Example 5) Oligomer synthesized in Synthesis Example 3 [11 parts 1 part by weight, N-
The same operation as in Example 3 was performed except that 1 part by weight of phenylmaleimide and 2 parts by weight of a 2% acetone solution of dicumyl peroxide were added to the test tube and mixed uniformly.

The resulting polymer was crushed in a mortar and subjected to thermogravimetric analysis at a heating rate of 10° C./min in air, resulting in the result as shown in (5) in FIG.

(Example 6) Oligomer synthesized in Synthesis Example 2 [111 parts by weight, N, N
The same operation as in Example 3 was performed except that 1 part by weight of -diphenylmethane bismaleimide and 2 parts by weight of a 2% acetone solution of dicumyl peroxide were added to the test tube and mixed uniformly.

The resulting polymer was crushed in a mortar and subjected to thermogravimetric analysis at a heating rate of 10° C./min in air, resulting in the result as shown in (1) in FIG.

(Example 7) 50 parts of oligomer [I] synthesized in Synthesis Example 2.

A solution prepared by dissolving 50 parts of N,N'-diphenylmethane bismaleimide and 1 part of dicumyl peroxide in 200 parts of dimethylformamide.

After dipping the glass cloth, it was dried at 100° C. for 1 hour to prepare a prepreg. Thereafter, several sheets of this prepreg were stacked together and heated and pressed at a pressure of 15 g/cm" and a temperature of 160° C. for 1 hour, and then cured at 200° C. for 5 hours to obtain a laminate.

The bending strength of this laminate is 56 kg/mi at 25°C.
The bending strength was 45 Kg/+u+" at 200°C, and the bending strength after heating at 230°C for 200 hours was 55 Kg/mw" at 25°C.

(Example 8) Oligomer [I] synthesized in Synthesis Example 2 1 part by weight, N,
Example 3 except that 0.5 parts by weight of N'-diphenylmethane bismaleimide, 1 part by weight of 0.5 parts of N-phenylmaleimide, and 2 parts by weight of a 2% acetone solution of dicumyl peroxide were added to the test tube and mixed uniformly. performed the same operation.

The obtained polymer was crushed in a mortar and subjected to thermogravimetric analysis at a heating rate of 10° C./min in air, resulting in the result as shown in (2) in FIG.

(Comparative Example 1) 1 part by weight of N-phenylmaleimide and 1 part by weight of a 2% acetone solution of dicumyl peroxide were added into a test tube, mixed uniformly, and placed in a 90° C. oil bath to evaporate acetone.

At this time, the mixture was a yellow homogeneous solution.

When this yellow homogeneous solution was heated to 120° C., it immediately generated white smoke, foamed significantly, and turned into a sponge-like solid. 120
After heating at .degree. C. for 3 hours, after-curing was performed at 200.degree. C. for 5 hours.

The resulting polymer was crushed in a mortar and subjected to thermogravimetric analysis at a heating rate of 10° C./min in air, resulting in the result as shown in (6) in FIG.

(Reference Example 1) An example in which the curing speed was improved by blending a maleimide derivative with the aromatic polyamide oligomer of the present invention was obtained using diallylisophthalamide, the oligomer [7 right and N-phenyl Table 1 shows the changes in curing speed when the blending ratio of maleimide was changed.

Note that dicumyl peroxide was a 2% acetone solution, and after it was added to one composition, the acetone was evaporated and then maintained at a predetermined temperature.

(Reference Example 2) A composition in which maleimide is added to an aromatic polyamide oligomer has a significantly lower melting point and is easier to process.

As an example, Table 2 shows the melting points of N-phenylmaleimide and the oligomer [1] obtained in Synthesis Example 2 at various mixing ratios.

(Margin below) Table [Effect J The present invention is a thermosetting polyamide resin with excellent heat resistance that does not lose the excellent properties of aromatic polyamide and does not deteriorate its mechanical properties even at high temperatures, A curable resin composition with improved curability and processability could be provided.

[Brief explanation of drawings]

FIG. 1 (1) is a thermogravimetric analysis diagram of the cured resin obtained in Example 1 in air. Similarly, +21131, (4), (5), (6
) is a thermogravimetric analysis diagram of the cured resins of Example 2.3.4.5 and Comparative Example 1 in air. Songs $1(1)j5 and (2) in FIG. 2 are the songs of Example (6).
It is a thermogravimetric analysis figure in the air of the resin cured material obtained in (8). Patent applicant Showa Kobunshi Co., Ltd.

Claims (4)

[Claims] (1) (i) A curable resin composition comprising an aromatic polyamide oligomer (b) maleimide derivative having an aliphatic unsaturated group at the end. (2) In claim 1, the aromatic polyamide has the general formula ▲ mathematical formula, chemical formula, table, etc. ▼ [However, in the formula, A is a radically polymerizable unsaturated group, R is a hydrogen atom, a lower alkyl group, or Lower alkenyl group, R_1
and R_2 is a group selected from divalent aromatic groups,
n represents a number from 0 to 15. ] An aromatic polyamide oligomer represented by: (3) The maleimide derivative according to claim 1, wherein the maleimide derivative is at least one of phenylmaleimide, aromatic dimaleimide, and aromatic polymaleimide. (4) In claim 1, polyamide oligomer 1
A curable resin composition comprising 10 to 200 parts by weight of a maleimide derivative based on 00 parts by weight.