JPH01201315A - Curable resin composition and cured molding - Google Patents

Abstract

PURPOSE:To obtain the title composition which can give an insoluble and infusible cured molding excellent in mechanical properties and heat resistance, by mixing a specified rigid polymeric substance with a thermosetting resin having ethylenic functional groups. CONSTITUTION:100pts.wt. rigid polymeric substance having diacetylene groups as crosslinking functional groups in the main chain of the polymer, containing structural units of formulas I and/or II (wherein Ar1-4 are each a 6-24C bivalent para-bonded aromatic hydrocarbon group, and R1-2 are each H or a 1-12C monovalent hydrocarbon group) and 5-900pts.wt. thermosetting resin having ethylenic functional groups, such as a maleimide resin of formula III (wherein R5 is a 6-18C m-valent hydrocarbon group, R3-4 are each R1, and m>=2) are dissolved in a common good solvent (e.g., N-methylpyrrolidone), and the formed solution is poured into a common solvent (e.g., methanol) in an amount 2-10 times larger than that of this solution to coprecipitate the resins, filtering off the coprecipitate and drying it to obtain the title composition. This product is packed into a mold and heated to 150-350 deg.C to obtain a cured molding of a bending modulus >=6 GPa.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a cured material comprising a polymer material having a crosslinkable functional group in its rigid polymeric main chain and a thermosetting resin having a polymerizable crosslinkable functional group. The present invention relates to a cured molded article having excellent mechanical properties and heat resistance obtained by curing the resin composition.

[Conventional technology]

Polymers with rigid main chains include para-bonded aromatic polyamides such as phenylene terephthalamide (PPTA), polyimides such as phenylene pyromellitimide, and heterocyclic rings such as polyphenylene benzthiazole, polyphenylene benzoxazole, and polyphenylene imidazole. Containing polymers and the like are well known as high performance polymers.

However, because the main chains of these polymers are too rigid, the temperature at which the molecular chains can move (Tg, glass transition temperature, Tm: melting point) is higher than the thermal decomposition temperature of these polymers, so they cannot be used normally. Since melt molding, which is a polymer molding method, is not possible, it is difficult to obtain molded bodies, and these rigid polymers are usually used in the form of films or fibers. Further, even when a molded body is obtained, the molding method is a special molding method, and the mechanical properties of the molded body are not necessarily excellent.

On the other hand, a cured thermosetting resin molded product with maleimide groups as a polymerizable functional group obtained by the reaction of an amine and maleic anhydride not only exhibits excellent heat resistance due to the contribution of the imide group, but also exhibits excellent heat resistance due to the contribution of the imide group. Since it is an addition reaction, there is no generation of volatile components, so it is attracting attention (Special public interest
4-20625).

However, because maleimide resin undergoes a three-dimensional crosslinking reaction through radical polymerization to form a high-density network structure, it suffers from large thermal contraction during curing, and the cured molded product is brittle.
Therefore, it has poor mechanical properties such as easy cracking due to heating and cooling, and various improvements have been made. For example, by creating a curable composition of bismaleimide resin and diamine, mechanical properties have been improved without reducing heat resistance (French Patent No. 11hl, 555, 5
Specification No. 64). In addition, compositions such as epoxy resins and polyfunctional allyl ester resins are also being studied (
JP-A-53-2190.54-10595.53-21
91.52-19598.52-19599.4B-1
9238, 49-12600). Further, compositions of polymeric substances such as polysulfone and bismaleimide resins have also been studied (Japanese Patent Laid-Open No. 47-5037
Publication No.).

In addition, certain diacetylene compounds are exposed to heat and γ in the crystalline state.
It is well known that polymerization can be caused by high-energy radiation such as radiation or ultraviolet radiation (tobochemical bolimerization). Regarding diacetylene, research has mainly focused on diacetylene compound monomers, and although there are some reports on polymers containing diacetylene groups, there are few research examples (Macromolecule Chemist).
mol.

Chew, ), 134 219 (1970),
Journal of Polymer Science Polymer Chemistry Edition (J, Polym, Sci.
, Polym.

Chew, Ed.), 19 1154 (198
1) In view of the above-mentioned properties of diacetylene groups, the present inventors have synthesized novel polymers containing diacetylene groups for the purpose of obtaining molded articles with excellent mechanical properties. We have studied polymer molded products with high mechanical properties by high-pressure molding of polymers in the solid state below their decomposition temperature or below their melting temperature.

[Problem to be solved by the invention]

A polymer with a rigid main chain is a high-performance polymer with excellent mechanical and thermal properties, but it is difficult to obtain a molded product and has poor moldability. It has been proposed that rigid polymers can be molded into molded bodies by introducing diacetylene groups into the chains, but since high pressure is used in the molding conditions, there are limitations on the molding equipment, molding molds, and shape of the molded bodies. Further, although maleimide resin has a high degree of heat resistance and excellent moldability, its cured molded product is brittle.

[Means to solve the problem]

In recent years, in the field of thermosetting resins, IPN (Inte
rpenetrating Polymer Netw
Composite materials with an interpenetrating network (orks) structure are attracting attention.

Unlike conventional polymer blends and graft polymers, this is characterized by the fact that two types of polymer main chains intertwine and form an entangled network structure.

By adopting an IPN structure, the two types of polymer main chains become intertwined, increasing the mutual compatibility of the polymers, resulting in an increase in crosslink density, a finer phase structure, and an increase in interlayer adhesion.As a result, a single polymer Excellent mechanical properties that cannot be obtained,
Demonstrates chemical resistance and heat resistance. The present inventors have conducted intensive studies to improve the mechanical properties and moldability of diacetylene polymers without impairing their high rigidity and heat resistance. Succeeded in further improving moldability without impairing mechanical properties by using a curable resin composition consisting of a rigid polymer material with a diacetylene group as a base and a thermosetting resin with an ethylenic functional group. However, the present invention was achieved.

That is, the present invention provides a curable resin composition comprising a rigid polymer substance having a diacetylene group as a crosslinkable functional group in the polymer main chain, and a thermosetting resin having an ethylenic functional group; Flexural modulus 6 obtained by curing the composition
This provides a cured molded product having a pressure of GPa or higher.

The rigid polymer having a diacetylene group as a crosslinkable functional group of the present invention is an aromatic polymer in which all of its bonds are para bonds, and in molecular model, it is a rod-shaped polymer that does not bend. The diacetylene group used as the crosslinkable functional group is also a non-bent crosslink, unlike ethylenic crosslinks.
It is a crosslinkable functional group that strengthens the rigidity of the polymer main chain.

Specifically, those containing the structural units shown in the following - Monana fl) and/or (2) are exemplified.

(In the formula, Art, Arz, Ar3, and Ar4 represent divalent para-bonded aromatic hydrocarbon groups having 6 to 24 carbon atoms.

R1 and R2 represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms. ) These divalent para-bonded aromatic hydrocarbon groups represented by Ar and ``Ar4 have the following structural formulas, and these aromatic hydrocarbon groups include aliphatic hydrocarbon groups, ether groups, and thioether groups. , a carbonyl group, a sulfone group, an ester group, an amide group, a urethane group, an azomethine group, etc. Furthermore, the hydrogen atom of the aromatic hydrocarbon group may be substituted with a halogen group, a hydrocarbon group, etc. Also good.

R1% R2 is hydrogen or 1 having 1 to 12 carbon atoms
is a valent hydrocarbon group. Examples of hydrocarbon groups include -C
111, -C2Hs, -C3H? , -C4H9,
-CHz-CH=CHz, -CHz-C-CH, etc. Preferably it is a hydrogen atom.

Examples of the rigid polymer containing a diacetylene group of the present invention include a para-bonded aromatic diamine having a diacetylene group represented by the skeleton of the above formula (1), and the above formula (2) and/or the following formula ( 4) A para-bonded aromatic dicarboxylic acid having a skeleton represented by the formula (2), and a para-bonded aromatic dicarboxylic acid having a diacetylene group represented by the skeleton of the formula (2) and the above formula +11 and/or the following formula (5). An example is a para-bonded aromatic polyamide produced from a para-bonded aromatic diamine having a skeleton.

(In the formula, Ars and total represent a divalent para-bonded aromatic hydrocarbon group having 6 to 24 carbon atoms, and R8 and R1 represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms.) , an aromatic polyimide produced using a rigid aromatic tetracarboxylic acid and its derivatives in place of the aromatic dicarboxylic acid, an aromatic tetraamino compound, an aromatic diaminodihydroxy compound in place of the aromatic diamine, or Examples include aromatic polyazoles with diacetylene groups all para-bonded, which are produced by using aromatic diaminodithiol compounds, and aromatic polyesters, which are produced from dicarboxylic acids having the skeleton of formula (2) and para-bonded aromatic dihydroxy compounds. can do.

In addition, the thermosetting resins having ethylenic functional groups of the present invention include maleimide resins, acrylic resins, styrene resins, nasiimide resins, acetylene-terminated resins, biphenylene-terminated resins, dicyano-terminated resins, cyanate ester resins, etc. Since no volatile components are generated during the process,
No voids are generated in the cured molded product. It is also possible to react with diacetylene groups in the rigid polymer main chain, and IPN
It is also expected that the structure will be strengthened. Among these, the maleimide resin represented by type (3) provides a cured molded product with particularly excellent mechanical properties and heat resistance.

(In the formula, R3 represents an m-valent hydrocarbon group having 6 to 18 carbon atoms. R3 and R4 are hydrogen atoms or 1 to 12 carbon atoms.
represents a valent hydrocarbon group. m represents an integer of 2 or more. ) Specifically, for example, N,N'-ethylene bismaleimide, N,N'-hexamethylene bismaleimide, N,
N'-dodecamethylene bismaleimide, N, N'-m-
Xylylene bismaleimide, N, N'-p-xylylene bismaleimide, N, N' -1,3-bismethylenecyclohexane bismaleimide, N, N' -1,4-bismethylenecyclohexane bismaleimide, N, N '
-2,4-) rylene bismaleimide, N, N' -2,
6-) Rylene bismaleimide, N,N'-3,3'-
diphenylmethane bismaleimide, N,N'-4,4
'-diphenylmethane bismaleimide, N, N'-3
, 3'-diphenylsulfone bismaleimide, N, N'
-4,4'-diphenylsulfone bismaleimide, N
, N'-4,4'-diphenylsulfide bismaleimide, N,N'-p-benzophenone bismaleimide,
N,N'-diphenylethane bismaleimide, N,N'
-diphenyl ether bismaleimide, )l, N'-(
methylene ditetrahydrophenyl) bismaleimide,
N, N'-(3-ethyl)-4,4'-diphenylmethane bismaleimide, N, N'-(3,3'-dimethyl)-4゜4'-diphenylmethane bismaleimide, N
, N'-(3,3'-diethyl)-4,4'-diphenylmethane bismaleimide, N,N'-(3,3'-
dichloro) -4,4'-diphenylmethane bismaleimide, N,N'-)lysine bismaleimide, N,N'-
Isophorone bismaleimide, N, N'-p, p-diphenylmethylsilyl bismaleimide, N, N'-diphenylpropane bismaleimide, N, N'-naphthalene bismaleimide, N, N'-p-phenylene bismaleimide, N , N'-m-phenylenebismale imide, N, N
In addition to bifunctional maleimide resins such as '-4,4'-diphenylmethane-bis-dimethylmaleimide,
In particular, polyfunctional maleimide compounds obtained by reaction of maleic anhydride with reaction products of aniline and formalin (polyamine compounds), 3,4.4'-)riaminodiphenylmethane, triaminophenol, etc. are particularly suitable for the composition of the present invention. This is a typical example of a maleimide resin suitable for products.

〔Production method〕

Methods for producing the polymer containing diacetylene groups, which is the first component, are exemplified by the following two methods.

The first method is a reaction between a diamine monomer containing a diacetylene group and a dicarboxylic acid derivative (reaction formula below), a reaction between a diamine monomer and a dicarboxylic acid derivative containing a diacetylene group, or a diamine containing a diacetylene group. It is produced by the reaction of monomers with dicarboxylic acid derivatives containing diacetylene groups.

(In the formula, produced by oxidative coupling reaction in the presence of

The maleimide resin represented by formula (3) is produced by reacting a polyvalent amine compound and a maleic anhydride derivative.

The composition of the present invention of a rigid polymer containing a diacetylene group and a thermosetting resin having an ethylenic functional group can be produced by a method commonly used, such as an extruder, Brabender, roll Melt blending using a blender or the like and dry blending using a mixer or the like are inappropriate. Since the Tg and Tta of the diacetylene group-containing rigid polymer of the present invention are higher than the thermal decomposition temperature, melt blending is inappropriate, and dry blending using a mixer etc. produces a very macroscopic blended state and is non-uniform. Therefore, it is inappropriate.

The optimal method for producing the composition of the present invention of a rigid polymer containing a diacetylene group and a maleimide resin is a solution blending method in which both are mixed as a homogeneous solution. That is, this is a method in which a rigid polymer containing a diacetylene group and a maleimide resin are dissolved in a common good solvent, and the solution is poured into a common poor solvent to co-precipitate.

As common good solvents, aprotic polar solvents such as N-methylpyrrolidone, dimethylacetamide, dimethylformamide, and hexamethylphosphoramide are used. These solvents may be used alone or in combination. Further, salts such as lithium chloride and calcium chloride may be present in these solvents.

Common poor solvents used to precipitate the curable resin composition by introducing the curable resin composition solution include alcoholic solvents such as methanol and ethanol, aliphatic solvents such as hexane and heptane, and water. . The amount of the poor solvent used is 2 to 10 times the amount of the good solvent. The precipitated solid is separated by a method such as filtration or centrifugation, and dried to obtain the curable resin composition of the present invention.

The ratio of the rigid polymer material to the thermosetting resin is 5 to 900 parts by weight of the thermosetting resin per 100 parts by weight of the rigid polymer material.
Parts by weight, preferably 10 to 500 parts by weight.

[Forming method]

The curable resin composition of the present invention can be easily molded by filling it into a mold and heating it.

The heat curing temperature ranges from 150°C to 350°C.

If it is below 150°C, it takes a long time to cure and is not economical, and if it is above 350°C, the curing reaction becomes too fast and is difficult to control.

The curable resin composition of the present invention can be cured under relatively mild conditions, and the resulting cured product has excellent mechanical properties and is an insoluble and infusible material with excellent heat resistance. It provides a heat-resistant polymer material.

The curable resin composition of the present invention is useful as a molding resin by incorporating inorganic fillers, flame retardants, pigments, etc. Further, the curable resin composition of the present invention is useful as a varnish for impregnation, lamination, adhesion, and film by making it into an organic solvent solution (varnish).

A curable resin composition comprising a rigid polymer substance having a diacetylene group as a crosslinkable functional group in the polymer main chain of the present invention and a thermosetting resin having an ethylenic functional group can be cured. The cured molded product having an IPN structure has a flexural modulus of 6 GPa or more, high strength, and excellent mechanical properties. Further, the heat distortion temperature is 250° C. or higher, and the heat resistance is also excellent. In addition, it can be molded using the same molding methods as ordinary thermosetting resins, and has excellent moldability as it can be molded into any shape. In this way, the cured molded product of the present invention is
Due to its excellent mechanical properties, heat resistance, moldability, etc., it is useful as a material for parts that require high performance, such as aerospace materials, precision mechanical parts, and electronic materials.

〔Example〕

Next, the present invention will be explained in more detail using examples.

Reference Example 1 Para-amide diacetylene polymer (1)
Production of (PA(p-APBI/TP)) 4.4'
A solution of 23.2 parts of -diaminodiphenylbutadiyne dissolved in 1000 parts of dry N-methylpyrrolidone containing 10% lithium chloride was cooled to 0°C, and 20.3 parts of sphthalic acid chloride was added in powder form. After reacting at 0°C for 1 hour, the reaction temperature was raised to room temperature and the reaction was continued for an additional 2 hours.
Amide diacetylene polymer (1)? g liquid was produced.

Reference Example 2 Para-amide diacetylene polymer (II
) Production of (PA(p-PDA/P-CPBI)) Paraphenylene diamine was used instead of 4,4'-diaminodiphenylbutadiine in Reference Example 1, and 4,4'-dichloroformyl was used instead of terephthalic acid chloride. A bara-amide diacetylene polymer (If) solution was prepared in the same manner as in Reference Example 1 except that phenylene butadiyne was used.

Reference Example 3 Meta-amide diacetylene polymer (PA
(m-ABPI/1-PT)) Production Reference Example 1-4,
3,3 instead of 4'-diaminodiphenylbutadiine
A meta-amide diacetylene polymer solution was prepared in the same manner as in Reference Example 1, except that '-diaminodiphenylbutadiine was used, dry N-methylpyrrolidone was used as the solvent, and isophthalic acid was used instead of terephthalic acid.

Example 1 Add 36 parts of N,N'-4,4'-diphenylmethane bismaleimide (DDM-BMI) to the para-amide diacetylene polymer (1) solution prepared in Reference Example 1 (mix and stir vigorously). PA (p-APBI/TP) and DDM-BMI were poured into a large amount of stirring water to precipitate both. After filtering the precipitate, it was washed twice with water and twice with methanol, and heated at 60°C under reduced pressure. I let it dry for a day and night.

The obtained composition was filled into a mold, pre-cured at 200°C for 2 hours using a hot press, taken out from the mold, and further post-cured at 250°C for 5 hours.

The cured molded body was heated using Autograph DSS-500 manufactured by Ichitsu Seisakusho.
When a bending test was conducted using
Pa, flexural modulus? , 7 GPa.

Example 2 The molded article obtained in Example 1 was further post-cured at 300°C for 5 hours. The bending strength of the obtained molded body was 150 MPa,
The flexural modulus was 7.3 GPa.

Examples 3 to 6 PA of Example 1 (p-^PBI/TP), DDM-
Cured molded bodies were obtained by changing the composition ratio of BMI and curing conditions. The mechanical properties of the cured molded product are shown in the table.

Examples 7 to 8 The same procedure as Example 1.2 was carried out except that the para-amide diacetylene polymer (1) solution of Example 1 was replaced with the para-amide diacetylene polymer (II) solution prepared in Reference Example 2. A molded body was obtained. The mechanical properties of the cured molded product are shown in the table.

Comparative Example I N,N'-4,4'-diphenylmethane bismaleimide (old DDM-B) was heated to 170°C, melted, poured into a mold, and cured at 200°C for 5 hours. No material was obtained that could be used for measuring mechanical properties due to cracks.

Comparative Example 2 However, under normal pressure, the polymer powders were not fused together and were in a disjointed state, making it impossible to mold them.

Comparative Examples 3 to 4 Implemented except that the polymer containing diacetylene groups was changed from a rigid para-based polymer (PA (p-APBI/TP)) to a meta-based polymer (PA (m-APBI/1-PT)) A cured molded product was obtained in the same manner as in Examples 1 and 2. The mechanical properties of the cured molded product are shown in the table. In this way, when a rigid polymer is not used, the flexural modulus is 6 GPa or less,
It does not have high mechanical properties.

Claims (4)

[Claims] (1) A curable resin composition comprising a rigid polymer substance having a diacetylene group as a crosslinkable functional group in the polymer main chain and a thermosetting resin having an ethylenic functional group. (2) The rigid polymer has the general formula (1) or/and (2)
) The composition according to claim 1, which contains a structural unit represented by: ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. (R_1 and R_2 represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms.) (3) The composition according to claim 1, wherein the thermosetting resin is a maleimide resin represented by the general formula (3). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R_5 represents an m-valent hydrocarbon group having 6 to 18 carbon atoms. R_3 and R_4 are hydrogen atoms or 1 to 1 carbon atoms.
2 represents a monovalent hydrocarbon group. m represents an integer of 2 or more. ) (4) A cured molded article having a flexural modulus of 6 GPa or more, which is a curing reaction product of a rigid polymeric substance having a diacetylene group in the polymeric main chain and a thermosetting resin having an ethylenic functional group.