JPS60240741A - Preparation of low-flow prepreg - Google Patents

Abstract

PURPOSE:To obtain the heat-resistant titled prepreg, suitable for the manufacture of a laminate having good accuracy in thickness and scarcely forming voids, by impregnating a reinforcement with a specified thermosetting resin composition, followed by heating thereof to polymerize the component in the composition. CONSTITUTION:A reinforcement such as various types of glass cloths is impregnated with a thermosetting resin composition comprising a polyfunctional cyanic acid ester (prepolymer) containing at least two cyanato groups in a molecule or a prepolymer of the ester with an amine (e.g. m-phenylenediamine) (A), and an alkenyl compound (prepolymer) containing at least one alkenyl group in a molecule [e.g. a polyallyl compound (polymer) such as diallyl phrhalate] (B), component A being in an amount of 50-99wt% when heat resistance is required, or component B being at least 50wt% when low flowability is required, and a polymerization initiator and thermosetting catalyst (C) in an amount of at least 10wt% of the total composition; and is heated to 50-200 deg.C to polymerize component B, giving the heat-resistant titled prepreg.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a novel heat-resistant, low-flow prepreg (one in which molten resin flows less until it hardens during laminated molding).
With regard to the manufacturing method, it is possible to manufacture laminates such as laminates and copper-clad laminates with good thickness accuracy and no voids.

[Conventional technology and its problems]

Conventionally, the B-stage process is carried out using a photopolymerizable resin composition - that is, a reinforcing base material is impregnated with a resin composition containing a photopolymerizable monomer or its prepolymer and a photosensitizer. Later, a method of producing prepreg by photopolymerization has been proposed, but it is difficult to achieve low fluidity, and it cannot be used for festivals that use solvents. In addition, the method of obtaining a B-stage prepreg by impregnating and drying a reinforcing base material with epoxy resin or the like to obtain a low-flow prepreg may cause variations due to uneven heating or other conditions, and some gelation may occur. It was difficult to produce a good low flow prepreg.

[Means for solving problems]

As a result of extensive research to eliminate the above-mentioned drawbacks, the present invention has been developed by adding a radically polymerizable monomer or prepolymer and its polymerization initiator to cyanate ester resin, resulting in low fluidity, good thickness accuracy, and void-free production. We have succeeded in obtaining a prepreg for manufacturing laminates that does not cause the occurrence of oxidation, leading to the present invention.

That is, the present invention provides a polyfunctional cyanate ester containing two or more cyanato groups in the A1 molecule, the cyanate ester prepolymer, or a prepolymer of the cyanate ester and an amine, at least one cyanato group in the B0 molecule. After impregnating a reinforcing base material with a thermosetting resin composition containing the above alkenyl compound having an alkenyl group, the alkenyl compound prepolymer, a C0 polymerization initiator, and a thermosetting catalyst as essential components, This is a method for producing a heat-resistant, low-flow prepreg characterized by polymerizing component B.

The present invention will be explained below.

[Configuration of the present invention, etc.]

Suitable polyfunctional cyanate esters as component A of the curable resin composition of the present invention have the following general formula tl) R(OCN)m -・------(1) (m in the formula is 2
The above is usually an integer of 5 or less, R is an aromatic organic group, and the cyanato group is bonded to the aromatic ring of the organic group. A specific example is 1.3-
or 1,4-dicyanatobenzene, 1,3.5-) licyanatobenzene, C3-, 1,4-', 1.6-. 1
．． 8-. 2.6- or 2.7-dicyanatonaphthalene,
1,3.6-)licyanatonafucrene, 4.4'-diaminobiphenyl, bis(4-diaminophenyl)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, and cyanic acid esters obtained by the reaction of novolacs with cyanogen halides. In addition to these, special public interest public works in 1928
, 43-18468, 44-4791, 45
-11712, 46-41112, 47-2685
Cyanic acid esters described in No. 3 and JP-A-51-63149 can also be used.゛Also, it is used as a prepolymer obtained by polymerizing the above-mentioned polyfunctional cyanate ester in the presence of a mineral acid, a Lewis acid, a salt such as sodium carbonate or lithium chloride, a phosphate ester such as tributylphosphine, etc. be able to.

These prepolymers are sym-) formed by trimerization of cyanide groups in the cyanate ester.
Generally has a riazine ring in the molecule. 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.

Examples of amines that can be suitably used include meta- or para-phenylene diamine, meta- or para-xylylene diamine, 1,4- or 1,3-cyclohexanediamine, cyclohydroxylylene diamine, 4,4-diaminobiphenyl, bis (4-aminophenyl)methane, bis(4
-aminophenyl) ether, bis(4-aminophenyl) sulfone, bis(4-amino-3-methylphenyl)methane\bis(4-amino-3,5-dimethylphenyl)methane, bis(4-aminophenyl) Cyclohexane, 2,2-his(4-aminophenyl)propane, 2
．． 2-bis(4-amino-3-methylphenyl)furopane, 2+ 2-his(4-amino-3-chlorophenyl)furopane, bis(4-amino-3-chlorophenyl)
Methane, 2,2-bis(4-amino-3,5-dibromophenyl)propane, bis(4-aminophenyl)phenylmethane, 3,4-diaminophenyl-4-aminophenylmethane, 1,1-bis( 4-aminophenyl)
-1-phenylethane and the like.

Of course, the polyfunctional cyanate esters mentioned above, their prepolymers and prepolymers with amines can be used in the form of mixtures.

The alkenyl compound or its prepolymer having at least one alkenyl group in the molecule of component B of the present invention is radical polymerized or crosslinked with a polymerization initiator under heating or drying conditions in the B-stage process. By doing so, it becomes a high molecular weight product. Specifically, polyallyl compounds such as diallyl phthalate, divinylbenzene, diallylbenzene, and trialkenyl isocyanurate and prepolymers thereof; dicyclopentadiene and prepolymers thereof; 4. t-bisallyloxydiphenylmethane, 4. Alkenylphenol compounds such as ibis allyloxydiphenylpropane, allyl phenyl ether, allyloxyfer ether, allyloxyphenol novorasoc, 〇- or p-amino-allyloxyphenol, bisallyloxyhydroquinone, allyloxyresorcin; (
4-hydroxy-3-allylphenyl)methane, bis(
4-hydroxy-2-allylphenyl)propane, bis(4-hydroxy-2-allylphenyl)sulfone, 0
-Allylphenol novolac, -Alkenylated phenol/-/L/-based compounds such as amino group-substituted -orthoallylphenol and eugenol; Monomers such as styrene, vinyltoluene, chlorostyrene, and bromostyrene, and one or two of these These include low molecular weight polymers, copolymers, etc., and polyallyl compounds are particularly preferably used.

Furthermore, as the polymerization initiator for component C1 of the present invention, the above-mentioned B
Any known component polymerization catalyst can be used. For example, peroxides such as hendyl peroxide, lauroyl peroxide, caprylic peroxide, acetyl peroxide, parachlorobenzoyl peroxide, di-tert-butyl perphthalate, potassium persulfate, ammonium persulfate, sodium perborate, etc. Examples include azo compounds such as azobisnitrile. Further, as the thermosetting catalyst of the present invention, 2-methylimidazole, 2-undecylimidazole, 2-heptadecyl imidazole, 2-phenylimidazole, 2-phenylimidazole,
-ethyl-4-methylimidazole, 1-benzyl-2
-Methylimidazole, 1-propyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethylimidazole, 1-cyanoethyl-2-undecylimidazole, ■-cyanoethyl-2-phenylimidazole, Imidazoles exemplified by 1-cyanoethyl-2-ethyl-4-methylimidazole and 1-guanamineethyl-2-methylimidazole, as well as adducts of carboxylic acids or their anhydrides to these imidazoles; N, N-
dimethylhensylamine, N,N-dimethylaniline,
N,N-dimethyltoluidine, N,N-dimethyl-p-
Anisidine, p-halogeno-N, N-dimethylaniline, 2-N-ethylanilinoethanol, tri-n-butylamine, pyridine, quinoline, ■-methylmorpoline, triethanolamine, triethylenediamine, N,
Tertiary amines such as N, N', N'-tetramethylbutanediamine and N-methylpiperidine; Phenols such as phenol, xylenol, cresol, resorcin, catechol, furo, and loglycine; Lead naphthenate, lead stearate , zinc naphthenate, zinc octylate, tin oleate, dibutyltin malate, manganese naphthenate,
Organic metal salts such as cobalt naphthenate and iron acetylacetonate; inorganic metal salts such as 5nC14, ZnCl2, AlCl3; maleic anhydride, phthalic anhydride, lauric anhydride, pyromellitic anhydride, trimellitic anhydride/hexahydrophthalic anhydride, Examples include acid anhydrides such as hexahydrotrimellitic anhydride and hexahydropyromellitic anhydride.

The amounts of the polymerization initiator and thermosetting catalyst added in the present invention are as follows:
A range of catalytic amounts in a general sense is sufficient, for example in amounts of up to 10 iyt%, usually up to a few %, based on the total composition.

Examples of the reinforcing base material of the present invention include various glass cloths such as cloth, roving cloth, Chosoptomat, and surfacing mat, quartz glass cloth, carbon fiber cloth, and other inorganic fiber cloths such as asbestos, rock wool, and slag wool. Examples include fully aromatic polyamide cloth, blended cloth of glass fiber and wholly aromatic polyamide fiber or carbon fiber, polyimide cloth, cotton cloth, linen cloth, felt, kraft paper, cotton paper, paper-glass blended paper, semi-carbon fiber cloth, etc. It will be done.

In the present invention, the curable resin composition, which requires the above-mentioned components, can be made into a solvent-free liquid composition at room temperature, or can be made into a face using a solvent, or some components can be dispersed in a liquid in the form of fine powder. The components of the present invention can be impregnated into a reinforcing base material as a colloidal liquid and dried by heating, or the components of the present invention can be prepared as a solid and this can be made into a fine powder and attached to the reinforcing base material by a known method such as a fluidized dipping method. - By heating and fusing, - By polymerizing the component mainly consisting of the C component in the resin component, the low fluidity B-stage prepreg of the present invention is obtained.

Here, the usage ratio of each component in the curable resin composition is 50 to 99% of component A when heat resistance is required.
-t%, preferably 60-85-t%. In addition, when placing particular emphasis on low fluidity of the obtained prepreg, B
50 wt% or more of the ingredients, preferably 60 to 85 wt%
Good to use.

The heating and drying conditions for B-stage are as follows:
Although it varies depending on the type and amount of the components used and the type and amount of the polymerization initiator, it is generally selected appropriately from the range of 50 to 200°C.

Although the present invention is as described above, various additives can be blended into the resin component as desired, as long as the original properties are not impaired. These additives include:
Contains various known additives such as natural or synthetic resins, fibrous reinforcing materials, fillers, dyes, pigments, thickeners, lubricants, campling agents, and H refueling agents, and can be used in appropriate combinations as desired. . Such resin components include polyfunctional maleimides containing at least two maleimide groups in the molecule, maleimide resins such as prepolymers of maleimides and amines; epoxy resins; thermosetting resins such as phenolic resins. Polyvinyl acecool resins such as polyvinyl formal, polyvinyl acecool, and polyvinyl butyral; Phenoxy resins; Acrylic resins with OH or C0OH groups; Silicone resins: Alxodo resins; Thermoplastic polyurethane resins; Polybutadiene, butadiene-acrylonitrile copolymer Combined, polychloroprene,
Uncrosslinked 41 (unvulcanized) rubbers such as butadiene-styrene copolymer, polyisoprene, butyl rubber, natural rubber;
Polyethylene, polypropylene, polybutene, poly-4
-Methylpentene-1, polyvinyl chloride, vinylidene chloride resin, polystyrene, polyvinyltoluene, polyvinylphenol, AS resin, ABS resin, MBS resin, poly-4-fluorinated ethylene, fluorinated ethylene-propylene copolymer, 4- Vinyl compound polymers such as fluorinated ethylene-6-fluorinated ethylene copolymer and vinylidene fluoride: polycarbonate, polyester carbonate, polyphenylene ether, polysulfone, polyester, polyether sulfone, polyamide, polyamideimide,
Polyesterimide, polyphenylene sulfide, and other resins are used in pots containing low molecular weight polymers of these thermoplastic resins with a molecular weight of 10,000 or less, usually 1,000 to several thousand.
prepolymers).

Conditions for producing laminates using the prepreg of the present invention vary depending on the type of curing agent, catalyst, composition components, etc., but are usually selected within the range of 100 to 3.0°C. It is preferable to apply pressure during heat curing,
Generally speaking O; 1-500 kg/cTA,
Preferably, it is appropriately selected within the range of 5 to 150 kg/Ca.

[Effect]

In the prepreg of the present invention made of the above-mentioned components, it is expected that the B component will be moderately polymerized (but not completely polymerized) and the A component will be prepared in the B-stage state in the prepreg drying process. As a result, the fluidity can be adjusted to be low, and laminated molding can be performed without adhesion or adhesion or voids caused by laminated molding.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. In addition, parts in Examples and Comparative Examples are parts by weight unless otherwise specified.

Examples 1 to 3 and Comparative Examples 1 to 4 2,2-bis(4-cyanatophenyl)propane 10
00g was preliminarily reacted at 160°C for 5 hours to obtain a prepolymer (referred to as (a)).

- Divinylhensen monomer (referred to as (b)).

- Trialkenyl isocyanurate monomer (referred to as tc+).

・Diallyl phthalate prepolymer (number average molecular weight 3,
000, +d+).

・Hisphenol A type epoxy resin (product name: Epicote 828, manufactured by Yuka Shell Epoxy@, called te+)
.

・Bis(4-maleimidophenyl)methane monomer (
ff)).

The above (al~(fl) were blended in the ratios shown in Table 1, sheet t-butyl peroxide ([1TBP) was used as a polymerization initiator, and zinc octylate ([1TBP] was used as a thermosetting catalyst).
After adding OCZN) and triethylenediamine (TEDA), they were dissolved and mixed in a mixed solvent of methyl ethyl ketone and N,N-dimethylformamide to prepare a face, and this face was continuously impregnated into a glass fiber woven fabric and dried. B
- stage prepreg was produced for J times.

A circular hole with a diameter of 5011 mm was made in the center of the obtained prepreg, and this was layered with an electrolytic copper foil with a thickness of 35 μm, a release film was placed on the other side, and it was sandwiched between mirror plates with a thickness of 21 mm.
/ CIA, laminate molding was carried out at 175° C. for 2 hours to obtain a laminate, and the maximum flow distance of the resin flowing into the holes of this plate and other characteristics of the laminate were also measured.

The results are shown in Table 1.

Table 1 [Effects of the Invention] As described above, in the prepreg manufactured by the manufacturing method of the present invention, a B-stage state with a moderate resin flow can be easily achieved, and a laminate with an excellent balance of physical properties can be obtained. On the other hand, it can be seen that in the case of the conventional method, the resin flow is too large (Comparative Example-1), or only a prepreg with no or almost no resin flow can be prepared, and it cannot be applied to a laminate.

Claims (1)

[Scope of Claims] A polyfunctional cyanate ester containing two or more cyanato groups in the A1 molecule, a prepolymer of the cyanate ester, or a prepolymer of the cyanate ester and an amine, at least one cyanato group in the B0 molecule. After impregnating a reinforcing base material with a thermosetting resin composition containing the above alkenyl compound having an alkenyl group, the alkenyl compound prepolymer, a C3 polymerization initiator, and a thermosetting catalyst as essential components, A method for producing a heat-resistant, low-flow prepreg characterized by polymerizing component B