JPH06316669A - Thermosetting resin composition - Google Patents

Abstract

PURPOSE:To provide a thermosetting resin composition composed of a polycarbodiimide compound, a cyanate group-containing aromatic compound and an epoxy group-containing compound, curable at a relatively low tempera ture and useful for production of a molding excellent in physical properties. CONSTITUTION:The composition is composed of (A) a polycarbo-diimide compound (preferably a carbodiimide copolymer having polymer ends blocked with an aromatic group and having <=10000 weight-average molecular weight) having two or more carbodiimide bonds in the molecule, (B) an aromatic compound having two or more cyanate groups in the molecule and (C) a compound (e.g. epichlorohydrin or diglycidyl ether of bisphenol) having an epoxy group in the molecule. In addition, the mixture ratio of the respective components is preferably to be A:B:C= (90 to 20):(5 to 80):(5 to 50) on weight base.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel thermosetting resin composition.

[0002]

2. Description of the Related Art Many thermosetting resin compositions containing polycarbodiimide as a main component are already known. Among them, a composition comprising polycarbodiimide and a dicyanate compound is a thermosetting resin having excellent physical properties. It is a curable resin composition. (For example, JP-A-2-218751)

[0003]

However, the composition comprising the polycarbodiimide and the dicyanate compound has a problem that it needs to be treated at a high temperature for a long time in order to be heat-cured.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a resin composition having a specific composition is thermally cured even at a low temperature. completed. That is, the present invention provides (A) 2 in the molecule.
A thermosetting resin composition comprising a polycarbodiimide compound having at least two carbodiimide bonds, (B) an aromatic compound having at least two cyanate ester groups in the molecule, and (C) a compound having an epoxy group in the molecule It is a thing. As the organic compound used in the present invention, which contains two or more carbodiimide bonds in the molecule, any organic compound having the structure of formula (1) [Chemical formula 1] in the molecular chain can be used, but polycarbodiimide is used. Is particularly preferable.

[0005]

## STR00001 ## -N = C = N- (1) Polycarbodiimide is a polymer compound having a large number of carbodiimide bonds in its molecular chain, and this compound itself is known, and carbodiimide of an organic polyisocyanate to an isocyanate is known. It can be produced in the presence of a catalyst that accelerates the formation.

Examples of organic polyisocyanates used are phenylene-1,3-diisocyanate, phenylene-1,4-diisocyanate, tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate, 1-methoxybenzene- 2,4-diisocyanate, 1-chlorophenylene diisocyanate, tetrachlorophenylene diisocyanate, metaxylylene diisocyanate,
Paraxylylene diisocyanate, diphenylmethane-
4,4'-diisocyanate, diphenyl sulfide-4,4 '
-Diisocyanate, diphenylsulfone-4,4'-diisocyanate, diphenylether-4,4'-diisocyanate, diphenylether-3,4'-diisocyanate, diphenylketone-4,4'-diisocyanate, naphthalene-2,6-diisocyanate, naphthalene − 1,4−
Diisocyanate, naphthalene-1,5-diisocyanate, 2,4'-biphenyldiisocyanate, 4,4'-biphenyldiisocyanate, 3,3'-methoxy-4,4'-biphenyldiisocyanate, anthraquinone-2,6-diisocyanate, tri Phenylmethane-4,4'-diisocyanate, azobenzene-4,4'-diisocyanate and dimers or higher polynuclears of these organic polyisocyanates and organic polyisocyanates are stoichiometric with respect to polyfunctional active hydrogen compounds. Examples thereof include terminal isocyanate prepolymers used in excess.

In the present invention, it is preferable to use a polycarbodiimide having a regulated molecular weight because the heat fluidity becomes better. This polycarbodiimide whose molecular weight is regulated can be produced from the above organic polyisocyanate and an organic monoisocyanate as a molecular weight modifier in the presence of a catalyst that promotes carbodiimidization of isocyanate. As the organic monoisocyanate used as a molecular weight regulator, phenyl isocyanate,
(Ortho, meta, para) -tolyl isocyanate, dimethylphenyl isocyanate, cyclohexyl isocyanate, methyl isocyanate, butyl isocyanate, chlorophenyl isocyanate, trifluoromethylphenyl isocyanate, naphthyl isocyanate, etc. can be exemplified, and organic polyisocyanate 100 mol 5 to 50 mol parts can be used with respect to parts.

Various catalysts can be used as the catalyst for promoting the carbodiimidization of isocyanate, but 1-phenyl-2-phospholen-1-oxide and 3-methyl-
1-phenyl-2-phospholen-1-oxide, 1-phenyl-2-phospholen-1-sulfide, 1-ethyl-2-phospholen-1-oxide, 1-ethyl-3-methyl-2-phospholen-1- Oxides, their corresponding isomers, and 3-phosphorenes are good. The amount of catalyst can be used in the range of 0.01 to 1% based on the total amount of isocyanate. In the present invention, the aromatic compound having two or more cyanate ester groups in the molecule is a compound having a cyanate group represented by the general formula (2) [Chemical Formula 2].

[0009]

Embedded image R ₁ — (— O—CN) _n (2) (In the formula, R ₁ is an aromatic polyvalent organic group, the cyanate ester group is an organic group, and the cyanate ester group is Is directly bonded to the aromatic ring of the organic group R ₁ , and n represents an integer of 2 or more, usually an integer of 10 or less.) The aromatic compound having at least 2 or more cyanate ester groups in the molecule is: Generally, known methods of reacting corresponding polyhydric phenolic compounds with cyanogen halides (see, for example, Japanese Patent Publication No.
No. 41-1928). Specific examples of the polyfunctional cyanate ester group are 1,3-or 1,4-dicyanate benzene, 1,3,5-tricyanate benzene, 1,3-, 1,4-, 1,6-, 1,8-, 2,6
-Or 2,7-dicyanatonaphthalene, 1,3,6-tricyanatonaphthalene, 2,2'- or 4,4'-dicyanatobiphenyl, bis (4-cyanatophenyl) methane, 2,2 -Bis (4-cyanatophenyl) propane,
2,2-bis (3,5-dichloro-4-cyanatophenyl) propane, bis (4-cyanatophenyl) ether, bis (4-cyanatophenyl) thioether, bis (4-cyanatophenyl) sulfone, Tris (4-
Cyanate phenyl) phosphite, tris (4-cyanatophenyl) phosphate, and a benzene polynuclear polyisocyanate compound obtained by the reaction of a phenolic resin and a cyanogen halide (for example, Japanese Patent Publication No. 45-117).
No. 12 and No. 55-9433). A divalent cyanate ester derived from a dihydric phenol such as 2,2-bis (4-hydroxyphenyl) propane because it is easily available, and gives good properties to the final resin. The compounds are particularly preferably used. Further, a polycyanate compound obtained by reacting an initial condensate of phenol and formaldehyde with cyanogen halide is also useful.

In the composition of the present invention, an aromatic compound having at least two cyanate ester groups in the molecule may be used alone, or an oligomer (prepolymer) derived from the aromatic compound may be used alone. You may mix and use these. The prepolymer has at least 2
It is obtained by polymerizing an aromatic compound having one or more cyanate ester groups in the presence of a catalyst such as mineral acid, Lewis acid, sodium carbonate, salts such as lithium chloride, or phosphoric acid esters. These prepolymers have an s-triazine ring formed by trimerization of a cyanate group in the molecule, and preferably have an average molecular weight of about 400 to 6000 (hereinafter abbreviated as cyanate ester compound). ).

In the present invention, as the compound having an epoxy group, any compound having an epoxy group in its molecule can be used. Specifically, epichlorohydrin, phenylglycidyl ether and styrene oxide can be used. Monofunctional epoxy compounds such as bisphenol diglycidyl ether, butanediol diglycidyl ether, novolac phenol glycidyl ether and its derivatives, glycidyl esters such as phthalic acid glycidyl ester, N-diglycidyl aniline, p-aminophenol Examples thereof include glycidyl amine such as glycidyl ether.

The composition of the present invention can be produced by mixing the above three components by a known method. As a mixing method, a compound containing a powdery carbodiimide bond, a diisocyanate compound and a powdery or liquid epoxy compound are mixed in a mixer such as a Henschel mixer, or three components are dissolved or dispersed in a solvent and mixed. Alternatively, it can be used as a liquid composition as it is, or can be used by removing the solvent by evaporation. In producing the composition, for example, tertiary amines such as triethylenediamine, N, N-dimethylbenzylamine and N-methylmorpholine, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methyl. Imidazoles such as imidazole, metal octylates, naphthenates, acetylacetone metal salts, stearates metal salts, butyl titanate, propylaluminum and other metal salts, tin tetrachloride, iron chloride, aluminum chloride and other chlorides like,
The curing reaction rate of the composition can also be increased by adding one or more catalysts capable of promoting cross-linking, preferably 0.01 wt% to 5 wt%.

In the present invention, (A) a polycarbodiimide compound having two or more carbodiimide bonds in the molecule, (B) an aromatic compound having at least two cyanate ester groups in the molecule, and (C) a molecule. The ratio of the compound having an epoxy group therein is 90 to 20: 5 in the weight ratio of (A) :( B) :( C) in claim 1.
80: 5 to 50 weight ratio, especially 80 to 30:10
It is preferably in the range of 50 weight ratio.

The composition of the present invention is usually heated to 100 to 150 ° C. to be molded into a desired shape, and then cured by heating to 150 ° C. or higher, preferably 200 to 400 ° C., and 5 to 100 kg / cm ^2. It is used by doing. Naturally, when using the composition, fillers, fibers, defoamers, flame retardants,
A release agent, a coloring agent and the like may be mixed and used.

[0015]

EXAMPLES Examples will be shown below to specifically describe the embodiments of the present invention. Example 1 Controlled molecular weight polycarbodiimide synthesized by heating diphenylmethane-4,4'-diisocyanate and phenylisocyanate in xylene in the presence of 3-methyl-1-phenyl-2-phosphorene-1-oxide catalyst. (Hereinafter abbreviated as PCI, average molecular weight of about 400
0) 62 parts by weight, 16 parts by weight of 2,2-bis (4-cyanatophenyl) propane (hereinafter abbreviated as BCPP, manufactured by Rhone-Poulin: trade name AcoCyB-10), and as an epoxy compound, Toto Kasei Co., Ltd. ) Is a reaction product of bisphenol A and epichlorohydrin. After mixing 16 parts by weight of EPOTOHTO YD128 (trade name, epoxy equivalent 188, Mw 376) thoroughly, first melt in a mold at 150 ° C, then 200
Thermocompression molding at a pressure of 40 kg / cm ² for 30 minutes at ℃, thickness approximately
A 1.6 mm laminated plate was obtained.

Room temperature (25 ° C) and hot (180
The physical properties at (° C.) and the storage stability of the powdery composition were as follows.

Comparative Example 1 The same procedure as in Example 1 except that the epoxy compound was not used, the curing was not sufficient at 200 ° C., the Barcol hardness was 24, and the following physical properties were obtained even when the curing temperature was 250 ° C.

Example 2 Epicoat 1002 manufactured by Yuka Shell Epoxy Co., Ltd. as an epoxy compound (trade name, epoxy equivalent 625, Mw 1060)
Was performed in the same manner as in Example 1 except that Met.

[0019]

INDUSTRIAL APPLICABILITY The composition of the present invention can be cured at a relatively low temperature, and a molded product having good physical properties can be obtained, which is extremely valuable industrially.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C08L 63/00 NKA 8830-4J

Claims (3)

[Claims] 1. A polycarbodiimide compound having (A) two or more carbodiimide bonds in the molecule, (B) an aromatic compound having at least two cyanate ester groups in the molecule, and (C) in the molecule. A thermosetting resin composition comprising a compound having an epoxy group. 2. The above (A) :( B) :( C) is 90-
The thermosetting resin composition according to claim 1, which has a weight ratio of 20: 5 to 80: 5 to 50. 3. The thermosetting resin according to claim 1, wherein the polycarbodiimide compound is a carbodiimide copolymer having a polymer molecule terminal blocked with an aromatic group and having a weight average molecular weight of 10,000 or less. Resin composition.