JPH0471096B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermosetting resin composition containing a novel curable resin as a component.

Conventionally, cyanate esters or prepolymers thereof, photopolymerizable or photocrosslinkable monomers or prepolymers thereof, and thermosetting monomers such as epoxy resins or prepolymers thereof are mixed and exposed to light and heat. It was known to be used in combination or heat-cured.

However, under practical conditions, the radical polymerizability and photopolymerizability of cyanate esters or their prepolymers themselves are small, and in order to cure in a short time, it is necessary to cure at a temperature of 170°C or higher. In addition, radical copolymerization and photococuring are extremely insufficient, and the curing of the above mixture is difficult.
It was necessary to carry out the process at a temperature of 170°C or higher, and the cured product had the drawbacks of being non-uniform.

The present invention was completed as a result of intensive studies to obtain a radical polymerization cured or photocurable resin while maintaining the excellent heat resistance and electrical properties of cyanate esters or their prepolymer cured products. By using a new curable resin,
Easier to cure than cured products of mixtures of known cyanate esters or their prepolymers, radically polymerizable monomers or their prepolymers, and thermosetting monomers or their prepolymers;
We have discovered a thermosetting resin composition that yields a cured product with significantly improved uniformity.

That is, the present invention provides: (a) a polyfunctional cyanate ester containing two or more cyanato groups in the molecule, the cyanate ester prepolymer, and (b) a 1,2-epoxy group and a radically polymerizable unsaturated double bond in the molecule. For one cyanato group of a, 1,2- of b
A thermosetting monomer c is added to a curable resin obtained by reacting epoxy groups in a ratio of 0.25 to 2 at a temperature of 90 to 140°C in the presence of a radical polymerization inhibitor and while blowing air. It is a thermosetting resin composition made by mixing a polymer or a prepolymer thereof.

The reaction for producing the novel curable resin, which is one component of the thermosetting resin composition of the present invention, is as follows:
It is obtained by selectively reacting the cyanato group of component and the 1,2-epoxy group of component b while suppressing the reaction of the unsaturated bonds of component b as much as possible.

First, the cyanato group of component a and the 1,2-
The ratio with the epoxy group is 1:0.25~ as shown above.
The ratio is 1:2, preferably in the range of 1:0.5 to 1:1.5, and the reaction temperature and time for selective reaction depend on the type and amount of impurities contained in both components.
Although it varies depending on the use/non-use, type, amount, etc. of the catalyst, the temperature is usually 90 to 140°C, preferably 95 to 130°C, and most preferably 100 to 125°C.
The time is 3 to 40 hours, preferably 4 to 30 hours. If the temperature is below 90℃, the reaction between cyanato groups and epoxy groups will be insufficient, and even if both components become gelled, they will separate and a homogeneous product will not be obtained.If the temperature exceeds 140℃, both components a and b will be separated. It is easy to gel and usually gels before a homogeneous product is obtained. The reaction is carried out in the presence of a radical polymerization inhibitor (reagent, etc.), without a catalyst, or in the presence of a catalyst that has a small effect of accelerating the multimerization reaction of cyanato groups at this temperature, and a large effect of accelerating the reaction of epoxy groups, without a solvent or at this temperature. It is carried out in the presence of a solvent by a batch method or a continuous method.

The curable resin obtained by the above reaction depends on the types and amounts of both components a and b used, and the use or non-use of a solvent, but for example, as component a, 2,2-bis(4-cyanatophenyl) is used. When propane is used without a solvent and glycidyl methacrylate is used as component b, it is usually a viscous transparent liquid, unreacted; self-condensation product of both components a and b; monomer of component a;
It is estimated that it consists of a trimer, pentamer, etc. with one or more b components bound together.

In addition, the reaction rate of the co-reactant of both components a and b or the reaction rate of component b varies depending on the use or non-use of a catalyst, the purity of components a and b used, etc. When used, even if the reaction amount of component b per 1 mole of component a is about 0.15 to 0.3 mole, it is usually obtained as a viscous transparent liquid in the absence of a solvent, and the comparison without the reaction of the present invention This method is completely different from the method described above in that it is possible to obtain a cured product that is uniform, transparent, and has significantly higher heat resistance.

The curable resin produced by the above method exhibits the excellent properties as described above even when used as is as a component of the present invention, and can be used as is or when heated at temperature.
Concentrate under reduced pressure at a temperature of about 20 to 105°C to remove all or part of the solvent, unreacted components of component B, and other low molecular weight compounds and low boiling point compounds, and form a viscous liquid, paste, or solid at room temperature. The method used is also preferred.

In addition, suitable polyfunctional cyanate esters as component a used in the production of the above-mentioned curable resin have the following general formula (1) R(-O-C≡N)m...(1) (Formula m is an integer of 2 or more and usually 5 or less, R is an aromatic organic group, and the cyanato group is bonded to the aromatic ring of the organic group. . Specific examples include 1,3- or 1,4-dicyanatobenzene, 1,
3,5-tricyanatobenzene, 1,3-. 1,
4-. 1,6-. 1,8-. 2,6- or 2,7
-dicyanatonaphthalene, 1,3,6-tricyanatonaphthalene, 4,4'-dicyanatobiphenyl, bis(4-dicyanatophenyl)methane,
2,2-bis(4-cyanatophenyl)propane, 2,2-bis(3,5-dichloro-4-cyanatophenyl)propane, 2,2-bis(3,5
-dibromo-4-cyanatophenyl)propane,
Bis(4-cyanatophenyl) ether, bis(4-cyanatophenyl) thioether, bis(4-cyanatophenyl) sulfone, tris(4
-cyanatophenyl) phosphite, tris(4
-cyanatophenyl) phosphate, cyanate esters from aromatic polycarbonate oligomers and cyanogen halides, and cyanate esters from novolak and cyanogen halides. In addition to these, Tokuko Shou 41-1928, Sho 43-
18468, 44-4791, 45-11712, 46-41112,
47-26853 and JP-A-51-63149, 51-
Cyanic acid esters described in 14995, 51-114494, etc. can also be used. These cyanate esters may be commercially available products and may be used as they are or after being purified.

Alternatively, the above-mentioned polyfunctional cyanate ester can be used as a prepolymer obtained by polymerizing it in the presence of a mineral acid, a Lewis acid, a salt such as sodium carbonate or lithium chloride, or a phosphate ester such as tributylphosphine. I can do it. These prepolymers generally have a sym-triazine ring in the molecule, which is formed by trimerization of the cyanide groups in the cyanate ester. In the present invention, it is preferable to use the prepolymer having a number average molecular weight of 300 to 6,000.

Furthermore, the polyfunctional cyanate esters described above can also be used in the form of prepolymers with amines.

As the compound having a 1,2-epoxy group and a radically polymerizable unsaturated double bond in the molecule, which is component b, a preferable substance has one 1,2-epoxy group in the molecule and is free from radical polymerization. It has one or more unsaturated double bonds, particularly preferably a glycidyl group as the 1,2-epoxy group and acryloyl or methacryloyl as the unsaturated double bond. Specifically, glycidyl acrylate, glycidyl methacrylate, glycidyl cinnamate (glycidyl cinnamate), epoxy obtained by reacting an epoxy compound containing two or more epoxy groups in the molecule with the carboxyl group of an unsaturated carboxylic acid. Compounds with a glucidyl group and acroyl or methacryloyl, such as compounds with a group and an unsaturated double bond, allyl glycidyl ether (1-allyloxy-2,3-epoxypropane), 1-(3-methyl- 2-Butenyloxy)-2,3-epoxypropane, 1-(3-butenyloxy)-2,3-epoxypropane, 1-(2-methyl-2-propenyl)-2,3-epoxypropane, 1-allyloxy- Examples include 3,4-epoxybutane and 1-allyloxy-4,5-epoxypentane.

The radical polymerization inhibitor is generally used as a radical polymerization inhibitor, and is a reagent or the like that quickly reacts with radicals and converts them into stable radicals or neutral substances. Specifically, diphenylpicrylhydrazyl, tri-p-nitrophenylmethyl, phenothiazine, benzoquinone, p-
tert-butylcatechol, hydroquinone, hydroquinone monoalkyl ether, nitrobenzene,
Examples include organic compounds such as dialkyldithiocarbamic acid metal salts; and oxygen and oxygen-containing gases. The amount of the radical polymerization inhibitor used as a reagent is preferably 0.01 to 0.1% based on the total amount of the raw material compounds used, and it is further preferable to introduce oxygen or an oxygen-containing gas into the reaction system and use it in combination.

The catalyst for selectively promoting the reaction between the cyanato group of component a and the 1,2-epoxy group of component b is a known curing catalyst used for epoxy resins as described above. Those that have a small promoting effect on the trimerization reaction under the above reaction conditions are suitable, and specifically, N,N-dimethylbenzylamine, N,N-dimethylaniline, N,N-
Dimethyltoluidine, N,N-dimethyl-p-anisidine, p-halogeno-N,N-dimethylaniline, 2-N-ethylanilinoethanol, tri-n-butylamine, pyridine, quinoline, N-
Tertiary amines such as methylmorpholine, triethanolamine, triethylenediamine, N,N,N',N'-tetramethylbutanediamine, N-methylpiperidine and R-X (X is Cl,
Quaternary ammonium salts (R ₄ N ⁺ ,
X ^- ); 2-methylimidazole, 2-undecylimidazole, 2-heptadecyl imidazole,
2-Phenylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-propyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethylimidazole , 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-guanaminoethyl-2-methylimidazole, and imidazoles exemplified by these; Addition of the following organic acids and acid anhydrides to imidazoles; trichloroacetic acid, oxalic acid, maleic acid, maleic anhydride,
para-toluenesulfonic acid, toluenesulfonic acid,
Phthalic anhydride, p-dichlorophthalic anhydride, succinic acid, lauric anhydride, pyromellitic anhydride, trimellitic anhydride, hexahydrophthalic anhydride,
Acids and acid anhydrides such as hexahydro trimellitic anhydride, hexahydropyromellitic anhydride, isocycinanuric acid; BF ₃ .O(C ₂ H ₅ ) ₂ , BF ₃ .O
Examples include (CH ₃ ) ₂ , BF ₃ ·piperidine adduct, triphenylphosphine, triphenylphosphite, triphenylphosphate, triphenylantimony, and iodine.

There is no particular restriction on the thermoplastic resin monomer or its prepolymer as component c of the present invention to be mixed with the above curable resin, but it may be selected as appropriate from the viewpoint of properties such as heat resistance of the cured product. . A suitable example is cyanate ester resin (so-called triazine resin: Tokkosho
41-1928 etc) Cyanate ester-maleimide resin (so-called bismaleimide triazine resin; Japanese Patent Publication No. 54-30440 etc.), Cyanate ester-maleimide-epoxy resin (Japanese Patent Publication No. 52-31279 etc.); Maleimide resins such as pre-reacted products with polyfunctional amines (product names: Kerimidd601, Rhone Poulenc, etc.), thermosetting polyimide resins such as thermosetting polyimide resins with acetylene groups at the ends (product names:
Thermid600, Gulf oil chemicals, etc.); Epoxy resins with two or more glycidoxy groups in the molecule; Unsaturated polyester resins; Unsaturated alkyd resins; 1,2-orl,4-polybutadiene; Epoxidized 1,2- Modified polybutadiene resins such as orl, 4-polybutadiene; thermosetting polyurethane resins; phenolic resins; acrylic resins with OH or COOH groups; silicone resins, and modified resins such as mixtures and pre-reacted products thereof. .

The blending ratio of the novel curable resin produced from components a and b of the present invention described in detail above and the thermoplastic resin as component c is not particularly limited, but usually component c is added to all of the composition. 1 to 99 wt%, preferably 5 to 80 wt%, most preferably 10 to 60 wt%, based on the resin component.

Further, the method for preparing the thermosetting resin composition of the present invention may be a conventionally known method, such as stirring the novel curable resin of the present invention and the thermosetting monomer of component c or its prepolymer. Method of simply mixing both components in a solvent and simply mixing them; Method of removing the solvent after mixing; Method of mixing without solvent using a kneader, roll, Banbury mixer, Henschel mixer, extruder, etc. at room temperature or heating Examples include a method of mixing.

The thermoplastic resin composition of the present invention has the property of undergoing a crosslinking reaction when heated to become a cured resin even as it is, but a curing agent or a curing catalyst is usually added and mixed in order to promote heat curing. These thermosetting catalysts or curing agents include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1-
Benzyl-2-methylimidazole, 1-propyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-
2-ethylimidazole, 1-cyanoethyl-2
-undecylimidazole, 1-cyanoethyl-
2-Phenylimidazole, 1-cyanoethyl-
Imidazoles exemplified by 2-ethyl-4-methylimidazole and 1-guanaminoethyl-2-methylimidazole, as well as adducts of carboxylic acids or their anhydrides to these imidazoles; N,N-dimethyl benzylamine,
N,N-dimethylaniline, N,N-dimethyltoluidine, N,N-dimethyl-p-anisidine,
p-halogeno-N,N-dimethylaniline, 2-
N-ethylanilinoethanol, tri-n-butylamine, pyridine, quinoline, N-methylmorpholine, triethanolamine, triethylenediamine, N,N,N',N'-tetramethylbutanediamine, N-methylpiperidine, etc. Tertiary amines: Phenols such as phenol, xylenol, cresol, resorcinol, catechol, phloroglycin; lead naphthenate, lead stearate, zinc naphthenate, zinc octylate, tin oleate, dibutyltin malate, manganese naphthenate , cobalt naphthenate, iron acetylacetonate, and other organic metal salts; SnCl ₄ , ZnCl ₂ , AlCl ₃ and other inorganic metal salts; benzoyl peroxide, lauroyl peroxide, caprylic peroxide, acetyl peroxide, parachlorobenzoyl peroxide, Peroxides such as di-tert-butyl-di-perphthalate; maleic anhydride, phthalic anhydride,
Acid anhydrides such as lauric anhydride, pyromellitic anhydride, trimellitic anhydride, hexahydrophthalic anhydride, hexahydro trimellitic anhydride, and hexahydropyromellitic anhydride; Furthermore, azo compounds such as azobisisobutylnitrile, and curing catalysts for epoxy resins. Examples include. The amount of these catalysts added is sufficient within the range of catalyst amounts in a general sense, for example, 10wt% based on the total composition.
It may be used in the following amounts.

The thermosetting temperature of the thermosetting resin composition of the present invention described in detail above varies depending on the presence or absence of a curing agent and catalyst, the types of composition components, etc., but is usually 100%
It is sufficient if the temperature is selected within the range of ~300℃.

This curable resin composition is used for various purposes such as paints, inks, cast products, molded products, laminates, tapes, sheets, films, and adhesives. The thermosetting resin composition of the present invention may contain various additives as desired, as long as the original properties of the composition are not impaired. Natural or synthetic resins include natural products such as rosin, silica, copal, and oil-modified rosin; dicyclopentadiene and its primer; polyvinyl acetal resins such as polyvinyl formal, polyvinyl acetal, and polyvinyl butyral; phenoxy resins; petroleum resins; Low molecular weight liquid to high molecular weight elastic rubbers such as butadiene-acrylonitrile copolymer, polychloroprene, butadiene-styrene copolymer, polyisoprene, butyl rubber, natural rubber; polyethylene, polypropylene, polybutene, poly-4-methylpentene -1, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyltoluene, polyvinylphenol, AS resin, ABS resin, MBS resin, poly-4-fluorinated ethylene, fluorinated ethylene-propylene copolymer,
Vinyl compound polymers such as 4-fluorinated ethylene-6-fluorinated ethylene copolymer and vinylidene fluoride; polycarbonate, polyester carbonate, polyphenyl ether, polysulfone, polyester, polyether sulfone, polyamide,
Examples include polyimide, polyadiimide, polyesterimide, polyphenylene sulfide, and the like. As reinforcing materials and fillers, various glass cloths such as cloth, roving cloth, chop mat, surfacing mat, quartz glass cloth, carbon fiber cloth, other asbestos, rock wool, etc.
Inorganic fibers such as slag wool, fully aromatic nylon cloth, blended cloth of glass fiber and fully aromatic nylon fiber, synthetic fiber cloths such as acrylic, vinylon, polyester, nylon, polyimide, cotton cloth, linen cloth, felt craft paper, Cotton paper, paper-glass blend paper, semi-carbon fiber cloth, etc., as well as fiber chips that make up these cloths and papers; glass powder, glass bulbs, silica, alumina, silica alumina, aluminum hydroxide, asbestos, calcium carbonate, Calcium silicate, wollastonite, carbon black, kaolin clay, calcined kaolin, mica, talc, iron oxide, synthetic mica, natural mica, semiconductors, boron nitride, other ceramics, aluminum, copper, iron, and various other materials. Can be mentioned.
In addition to these additives, dyes, pigments, thickeners,
Various known additives such as lubricants, coupling agents, and flame retardants are included, and can be used in appropriate combinations as desired.

The present invention will be explained in more detail below using Examples and Comparative Examples.

Example 1 50 g of 2,2-bis(4-cyanatophenyl)propane (cyanato group equivalent: 139), 50 g of glycidyl methacrylate (epoxy equivalent: 142 or less, referred to as GMA), and 0.06 g of phenothiazine were placed in a glass container, and the temperature was adjusted while blowing air. 120~125℃
The mixture was heated to 100% and reacted for 10 hours with stirring.

60 wt part of this reactant has an epoxy equivalent of 450 to 500.
40 wt parts of bisphenol A type epoxy resin was added and dissolved and mixed in methyl ethyl ketone. The gelation time of this mixture at 160°C was 15 minutes. Furthermore, as a catalyst, dicumyl peroxide 0.2wt
part and 0.02wt part of zinc octylate were mixed. The gelation time of this mixed solution at 160°C was 240 seconds.

Impregnate a glass cloth with a thickness of 0.2 mm with the mixed solution, and
℃, 5 minutes drying, kelization time 60 seconds (at 170℃),
A prepreg with a resin content of 43wt% was created, and this was
The sheets were stacked and laminated at 40 kg/cm ² at 150° C. for 6 hours to produce a laminate.

The glass transition temperature of this laminate was 196°C.

Comparative Example 1 2,2-bis(4-cyanatophenyl)propane was reacted at 140°C for 6 hours to produce a cyanate ester resin prepolymer. 50wt part of this resin and 50wt part of GMA, the same epoxy resin as in Example 1
Add 67wt part, dissolve and mix in methyl ethyl ketone, and use 0.33wt of dicumyl peroxide as a catalyst.
part and 0.033wt part of zinc octylate were mixed.

Impregnate a glass cloth with a thickness of 0.2 mm with this mixed solution.
Although it was dried at 120°C for 5 minutes, GMA evaporated during drying, leaving only 75 wt% of the amount deposited as a resin component (84% of the added GMA evaporated during drying).

Example 2 42 g of 1,4-dicyanatobenzene and 50 g of glycidyl methacrylate were added to benzyldimethylamine.
0.5 g and 0.04 g of phenothiazine were reacted at 125 to 130° C. for 6 hours while blowing air (hereinafter referred to as resin A).

Further, 2,2-bis(4-cyanatophenyl)propane was heated at 140°C for 6 hours to produce a cyanate ester resin prepolymer (hereinafter referred to as resin B).

After mixing 50wt parts each of resins A and B at 80℃,
0.3 wt part of t-butyl peroxybenzoate was mixed, and a 3 mm thick plate was cast and cured by heating at 160°C for 5 hours. The glass transition temperature of this cured product is 225
It was warm at ℃.

Comparative Example 2 1,4-dicyanatobenzene was heated at 135°C for 5 hours (hereinafter referred to as resin C).

Further, 2,2-bis(4-cyanatophenyl)propane was heated at 140°C for 6 hours to produce a cyanate ester resin prepolymer (hereinafter referred to as Resin D).

After mixing 50wt parts each of resins C and D at 80℃,
0.3 wt part of t-butyl peroxybenzoate was mixed, and a 3 mm thick plate was cast and cured by heating at 160°C for 5 hours.

The glass transition temperature of this cured product was 183°C.

Example 3 70 g of 2,2-bis(4-cyanatophenyl)propane, 30 g of GMA and 0.04 g of phenoteazine
Place it in a glass container and bring it to the temperature while blowing air into it.
The mixture was heated to 120-125°C and reacted for 9 hours with stirring.

To 80 wt parts of this reaction product, 20 wt parts of an unsaturated alkyd resin produced from maleic anhydride and ethylene glycol were mixed, and 0.5 wt parts of benzoyl peroxide were mixed therein.

Apply this to a thickness of 30μ on a metal plate,
It was heated at ℃ for 20 minutes to obtain a coating film with a surface hardness of 6H.

Claims (1)

[Scope of Claims] 1. A polyfunctional cyanate ester containing two or more cyanato groups in the molecule, the cyanate ester prepolymer, and b. A compound having a double bond is added to one cyanato group of a to 1,2- of b.
Epoxy groups are mixed at a ratio of 0.25 to 2 in the presence of a radical polymerization inhibitor, and the temperature is increased while blowing air.
A thermosetting resin composition obtained by mixing a c thermosetting monomer or a prepolymer thereof with a curing resin obtained by reacting at 90 to 140°C.