JP3608005B2 - Curable resin composition, prepreg, compound and cured product - Google Patents

Description

【００４５】
表−１からわかる通り、本発明実施例１〜３の硬化物は、化合物（Ｃ）の添加がない比較例１，２の硬化物に比べて酸素指数が高い、つまり難燃性が優れていることがわかる。
【００４６】
実施例４〜６、比較例３〜４
これら配合例で得られた液と合成例で得られた液に硬化促進触媒として塩化ベンジルを樹脂液に対して３％添加したものを３０部に、溶融シリカを６０部、さらにチョップドストランドガラス［旭ファイバーグラス（株）社製：ＣＳ０３ＭＡ ＰＸ−１］を１０部混合してロールにて混練してコンパウンドを作製した。得られたコンパウンドについて、金型にて圧縮成形を実施した。この検討結果を表−２にまとめた。
【００４７】
【表２】

【００４８】
表−２からわかる通り、本発明実施例４〜６の組成物の増粘により、良好なコンパウンドを与え、圧縮成形しても樹脂の流れを押えるものとなり、成形性が非常に良好となる。化合物（Ｃ）の添加がない比較例３，４はコンパウンド作製時に増粘を図るのが困難であり、成形時も樹脂の流動性が高すぎて成形しずらいものである。つまり本発明の組成物が成形性が格段に優れていることがわかる。
【００４９】
【発明の効果】
本発明の硬化性樹脂組成物は、任意に組成物の増粘が可能であり、すべて付加反応と重合反応を利用することになるので、ガスの発生無しに硬化させることが可能であり、しかも、従来の硬化性樹脂に比べ、難燃性も向上したものである。[0001]
[Industrial application fields]
The present invention relates to a curable resin composition, a prepreg, a compound, and a cured product.
[0002]
[Prior art]
U.S. Pat. No. 4,200,706 describes a curable composition comprising a novolac-type phenolic resin and divinylbenzene.
[0003]
The present inventor tried to prepare the composition based on the above specification, but there was a problem that both components were separated and could not be mixed uniformly.
Therefore, the present inventors searched for a novolak-type phenolic resin excellent in compatibility with divinylbenzene, and a novolac-type phenolic resin or a phenol-dicycloalkadiene-based resin having a particularly high ortho / para ratio is suitable. Have already found out.
[0004]
Unlike conventional phenolic resin compositions, this resin composition has the advantage of not generating gas during curing, and problems such as degassing during molding, odor of generated gas, shrinkage during curing, distortion during curing, etc. Is a solution.
[0005]
[Problems to be solved by the invention]
However, curable resin compositions containing only novolac-type phenolic resin and divinylbenzene are liquid and easy to handle, such as pultrusion molding, FW (filament winding) molding, RIM (reaction injection molding) molding, etc. Although it is suitable for this molding method, it is not suitable for BMC (bulk molding compound) molding, for example, when thickening is required as a compound.
[0006]
Although it is possible to thicken with a filler or a fiber base material, when the composition is molded at a high temperature, the resin itself is too low in viscosity, so that only the resin content is in the mold and the mold. There was a drawback that it flowed as burrs from and became a non-uniform molded product.
[0007]
An object of this invention is to provide the curable resin composition which can increase the viscosity of a composition arbitrarily.
[0008]
[Means for Solving the Problems]
Therefore, the present inventors have conducted intensive studies in view of the above-described actual situation, and as a result, a resin (A) which is a novolac type phenol resin and / or a phenol-dicycloalkadiene resin, and divinylbenzenes (B) are used as components. It has been found that the above problem can be solved by adding a compound (C) having one maleimide structure as an essential component to the curable resin, and the present invention has been completed.
[0009]
That is, the present invention includes as essential components a resin (A) which is a novolak type phenol resin and / or a phenol-dicycloalkadiene resin, a divinylbenzene (B), and a compound (C) having one maleimide structure. A curable resin composition is provided.
[0010]
The resin (A) which is a novolak type phenol resin and / or a phenol-dicycloalkadiene resin used in the present invention is not particularly limited, but preferably has a number average molecular weight of 200 to 2,000. And more preferably 300 to 1,000.
[0011]
Examples of such a resin (A) include a formaldehyde supply substance and phenols, an acid catalyst such as oxalic acid, hydrochloric acid, and sulfuric acid, a metal oxide such as zinc acetate, lead acetate, and zinc oxide, and a metal salt catalyst. A conventional phenolic novolak resin obtained by reacting in the presence of a molar ratio of 0.5 to 1.0, or a phenol-dicyclopentadiene resin obtained by the reaction of phenol and dicyclopentadiene; Examples include resins obtained by polymerizing vinylphenol, isopropenylphenol, and the like. Resin (A) can be used as a further modified resin, and several kinds of resins may be used in combination.
[0012]
The resin (A) according to the present invention is not limited to those in which aromatic hydrocarbons are bonded only by methylene bonds, which are generally referred to, but aromatic hydrocarbons are bonded by methylene bonds and dimethylene ether bonds. What is doing can also be used.
[0013]
Among the above resins (A), for example, a high-orthophenol novolak resin having many methylene bonds at the ortho position of the phenolic hydroxyl group, in particular, the ratio of the orientation between the ortho and para positions (ratio of o / p) is 4 or more. And a phenol-dicycloalkagen-based resin are preferable because they have good compatibility with the ethylenic double bond and can be easily mixed with the compound (B) described later. Examples of the dicycloalkadiene include dicyclopentadiene.
[0014]
The method for producing the resin (A) is not particularly limited. The resin (A) may be used alone, but several different types may be used in combination.
[0015]
Any known and commonly used divinylbenzenes (B) according to the present invention can be used, and examples thereof include divinylbenzene, alkyldivinylbenzene, and halides of divinylbenzene. Among these, as the compound (B), divinylbenzene is more preferable in terms of excellent reactivity with the resin (A), workability during preparation of the composition, and the like. The compound (B) may be used alone or in combination of two or more.
Instead, two or more types may be mixed and used.
[0016]
In the compound (B), another reactive third component can be used in combination as necessary. Other third components in this case include, for example, aromatic monovinyl compounds such as styrene, methylstyrene, ethylstyrene, and monobromostyrene, (meth) acrylic acid methyl ester, (meth) acrylic acid stearyl ester, and (meth) acrylic. Examples thereof include aliphatic monovinyl compounds such as acid, N-methylol (meth) acrylamide, and γ-mercaptopropyltrimethoxysilane. Among these, these third components can be used not only alone but also in combination of two or more.
[0017]
As the compound (C) having one maleimide structure, any known and commonly used compounds can be used. Examples thereof include phenylmaleimides, phenylmaleimides represented by parahydroxyphenylmaleimide, and benzylmaleimide. In addition, you may use a compound (C) not only by single use but in mixture of 2 or more types.
[0018]
The curable resin composition of the present invention can be easily obtained by mixing the resin (A), the compound (B) and the compound (C) as essential components.
The resin (A) and the compound (B) in the curable resin composition in the present invention may be synthesized by synthesizing the compound (B) in the same reactor immediately after synthesizing the resin (A). The resin (A) may be once taken out from the reactor, and the resin (A) and the compound (B) may be newly mixed in a separate container.
[0019]
The mixing ratio of the resin (A) and the compound (B) is not particularly limited and may be appropriately selected depending on the types of the resin (A) and the compound (B) to be used. It is a linking group in the resin (A) with respect to the number of reaction positions of the aromatic hydrocarbon skeleton (for example, in the case of phenol, the ortho-position and para-position correspond, and the number of reaction positions is 2). The total of the methylene group and the ethylenically unsaturated double bond of compound (B) should be around the equivalent. Preferably, it is in the range of 1.2 equivalents to 0.8 equivalents.
[0020]
The resin (A) and the compound (B) may be mixed at room temperature or may be mixed under heating, but it is preferable to carry out at around room temperature as much as possible in terms of low heat generation and high safety. When the aromatic hydrocarbon having a phenolic hydroxyl group is contained in the resin (A), it functions as a polymerization inhibitor and can be mixed at room temperature or under heating.
[0021]
What is necessary is just to mix the compound (C) which has one maleimide structure of this invention with the mixed component of resin (A) and a compound (B). The compound (C) may be mixed in advance with the resin (A), or may be mixed with a mixture of the resin (A) and the compound (B). When the mixture of the resin (A) and the compound (B) is in a liquid state, it is preferable to add the compound (C) as close to room temperature as possible because the change in system viscosity is small.
[0022]
The mixing ratio of the compound (C) is not particularly limited and may be appropriately selected depending on the desired degree of thickening, but is usually 100 parts by weight in total of the resin (A) and the compound (B). 2 to 50 parts by weight. Preferably, it is the range of 5-20 weight part. When the amount is small, the thickening effect is small, and when the amount is large, the handling becomes difficult.
[0023]
When preparing the curable resin composition of this invention, you may add water and an organic solvent as needed.
Examples of the organic solvent include toluene, xylene, terpene, methanol, methyl ethyl ketone, and the like.
[0024]
As the reaction of the composition of the present invention, the compound (B) acts as a crosslinking agent for the resin (A), and the double bond of (B) is added to the aromatic nucleus of (A); )) And a double bond of (C) are polymerized. The latter reaction has a higher priority at low temperatures and the former reaction at a higher temperature.
[0025]
The curable resin composition of the present invention obtained as described above can be cured by adding a curing accelerating catalyst as necessary and at room temperature or by heating.
[0026]
Examples of the curing accelerating catalyst include metal chlorides such as aluminum chloride and stannous chloride, inorganic acids such as sulfuric acid, hydrochloric acid and phosphoric acid, organic sulfonic acids such as benzenesulfonic acid and paratoluenesulfonic acid, acetic acid and oxalic acid. In addition to organic carboxylic acids such as maleic acid, sulfonated compounds derived from the resin (A), phosphites such as phosphorous monophenyl, esters derived from sulfuric acid and organic sulfonic acids such as p -Latent catalysts represented by methyl toluene sulfonate, salts such as ammonium chloride, benzyl chloride, chloromethylstyrene, benzoyl chloride, sulfonium salts of metal halides, etc. The thing which produces | generates a component is mentioned. These curing accelerators may be used alone or in combination of two or more. As the curing accelerating catalyst, a latent catalyst such as a sulfonium salt is preferable in that a uniformly mixed composition can be easily obtained and the life of the blend can be easily adjusted. Although the usage-amount of these hardening acceleration | stimulation catalysts is not restrict | limited, 0.1 to 5.0% of composition weight is preferable.
[0027]
The curing time of the resin compound according to the present invention varies depending on the type of resin (A), compound (B) and compound (C) used, the mixing ratio, the type and amount of the curing accelerating catalyst, and is appropriately mixed and cured. It is preferable to select and adjust optimum conditions.
[0028]
The curable resin composition of the present invention can be handled as a single stable solution and can be uniformly cured without generating gas.
[0029]
The curable resin composition of the present invention may be used in combination with other thermosetting resins or thermoplastic resins as necessary. The resin used in combination is not particularly limited.
[0030]
The curable resin composition of the present invention may be cured by using the resin (A), the compound (B), and the compound (C) as essential components, and if necessary, a reinforcing material and a filler are mixed into the composition. It is practical to use.
[0031]
Further, the cured product obtained by curing the composition of the present invention has an effect that the flame resistance is remarkably improved as compared with a cured product obtained by curing the conventional resin (A) and compound (B).
[0032]
The composition of the present invention can produce a curable prepreg, for example, by impregnating a fiber base material with a composition comprising a resin (A), a compound (B) and a compound (C), and a curing accelerating catalyst. . This curable prepreg can be cured by heating at normal pressure or under pressure. As the reinforcing material, any known and commonly used fiber reinforcing material can be used. For example, glass fiber, ceramic fiber, asbestos fiber, carbon fiber, inorganic fiber such as stainless steel fiber, natural fiber such as cotton and hemp, polyester And synthetic organic fibers such as polyamide. The shape of the reinforcing material is not limited at all, and any material such as a short fiber, a long fiber, a yarn, a mat, or a sheet may be used.
[0033]
Any known and commonly used fillers can be used, and examples thereof include silica, calcium carbonate, aluminum hydroxide, talc, clay, graphite and the like. These reinforcing materials and fillers can be used not only alone but also in a mixture of two or more, and the amount of use should be adjusted according to the application and required performance.
[0034]
The curable resin composition of the present invention can be crosslinked and cured by molding alone or in combination with a reinforcing material or a filler. As the molding method, an injection molding method, a RIM method (reactive injection molding), an SMC method, a hand lay-up method, a pultrusion molding method, or the like can be adopted, but the molding method is particularly limited. Not what you want.
[0035]
The curable resin composition of the present invention has excellent mixing stability and can be cured uniformly, so that it maintains the flame retardancy, low smoke generation, heat resistance, strength, etc., which are the advantages of phenolic resin, and at the same time, has the disadvantages. It also solves the workability, curability, moldability, shrinkability, distortion, color tone, and the like. The synthetic resin composition of the present invention can be used not only for curing the synthetic resin composition alone, but also for curing together with known and commonly used reinforcing materials and fillers, and is useful for various applications. Become.
[0036]
The synthetic resin composition of the present invention includes, for example, various molding materials, binders for foundry sand, binders for grinding wheels, adhesives, binders for friction materials, binders for refractory materials, binders for heat insulating materials, foam materials , Resin concrete, rubber reinforcing agents, paints for various applications, coating agents, etc., not only in fields where novolak resins have been used, but also in fields where resole phenolic resins, unsaturated polyester resins have been used Can be expected to improve performance.
[0037]
【Example】
Hereinafter, the present invention will be described with reference to synthesis examples of resins that are novolak-type phenol resins and / or phenol-dicycloalkadiene resins, preparation of curable resin compositions, and application examples. All parts and% in the examples are based on weight.
[0038]
Synthesis Example 1 940 g (10 mol) of phenol, 281 g (7.5 mol) of 80% paraformaldehyde, and 470 g of xylene were added to a four-necked 2 liter flask equipped with a stirrer, a condenser, a thermometer, and a dropping funnel, and stirred. Started. As a catalyst, 4.7 g of zinc acetate dihydrate was added, and the temperature was raised to the reflux temperature. After reacting under reflux for 5 hours, distillation was started and the temperature was raised to 130 ° C. while removing water and xylene as a solvent. After maintaining at 130 ° C. for 1 hour, the temperature was raised to 150 ° C. while distillation. Furthermore, after partially removing free phenol under reduced pressure, the precipitated catalyst was taken out while filtering to obtain a solid high ortho novolac type phenol resin having a melting point of 58 ° C. To 100 parts of the resulting novolak-type phenol resin, 75 parts of divinylbenzene as a curing agent was dissolved at 50 ° C. to obtain a uniform tan liquid having a viscosity of 150 cps (25 ° C.).
[0039]
Synthesis example 2
Phenol-dicyclopentadiene resin: DPP-600H [manufactured by Nippon Petroleum Co., Ltd., number average molecular weight 580, raw material phenols are phenol] 100 parts, divinylbenzene 64 parts and ethylstyrene 16 parts Was dissolved at 50 ° C. to obtain a uniform reddish brown solution having a viscosity of 520 cps (25 ° C.).
[0040]
<Formulation example 1>
In 100 parts of the synthetic resin composition obtained in Synthesis Example 1, 20 parts of P-hydroxyphenylmaleimide was blended and dissolved at room temperature to obtain a uniform tan liquid.
[0041]
<Formulation example 2>
To 100 parts of the synthetic resin composition obtained in Synthesis Example 1, 10 parts of P-hydroxyphenylmaleimide was blended and dissolved at room temperature to obtain a uniform tan liquid.
[0042]
<Formulation example 3>
20 parts of phenylmaleimide was blended with 100 parts of the synthetic resin composition obtained in Synthesis Example 2 and dissolved at room temperature to obtain a uniform reddish brown liquid.
[0043]
Examples 1-3, Comparative Examples 1-2
A solution obtained by adding 0.5% of p-toluenesulfonic acid as a curing accelerating catalyst to the solution obtained in these formulation examples and the synthesis example with respect to the resin solution was cured by heating at 180 ° C. for 1 hour. About the obtained hardened | cured material, bending strength (JIS K-6911), heat-deformation temperature (ASTM D648), and oxygen index (JIS K-7201: candle type combustion measuring machine use) were measured. The measurement results are shown in Table 1.
[0044]
[Table 1]

[0045]
As can be seen from Table 1, the cured products of Examples 1 to 3 of the present invention have a higher oxygen index than the cured products of Comparative Examples 1 and 2 without the addition of the compound (C), that is, excellent flame retardancy. I understand that.
[0046]
Examples 4-6, Comparative Examples 3-4
30 parts of the liquid obtained in these blending examples and the liquid obtained in the synthesis example with 3% benzyl chloride added to the resin liquid as a curing accelerating catalyst, 60 parts of fused silica, and chopped strand glass [ Asahi Fiber Glass Co., Ltd. product: CS03MA PX-1] was mixed 10 parts and kneaded with a roll to prepare a compound. About the obtained compound, compression molding was implemented with the metal mold | die. The results of this study are summarized in Table 2.
[0047]
[Table 2]

[0048]
As can be seen from Table-2, by increasing the viscosity of the compositions of Examples 4 to 6 of the present invention, a good compound is provided, and even when compression molding is performed, the flow of the resin is suppressed, and the moldability becomes very good. In Comparative Examples 3 and 4 without the addition of the compound (C), it is difficult to increase the viscosity at the time of preparing the compound, and the fluidity of the resin is too high at the time of molding to make it difficult to mold. That is, it can be seen that the composition of the present invention is remarkably excellent in moldability.
[0049]
【The invention's effect】
The curable resin composition of the present invention can arbitrarily increase the viscosity of the composition, and since all use an addition reaction and a polymerization reaction, it can be cured without generating gas. Compared to conventional curable resins, flame retardancy is also improved.

Claims (10)

A curable resin composition comprising, as essential components, a resin (A) which is a novolak-type phenol resin or a phenol-dicycloalkadiene resin, a divinylbenzene (B), and a compound (C) having one maleimide structure . The composition according to claim 1, wherein the resin (A) is a novolac type phenol resin. 3. The composition according to claim 2, wherein the novolac type phenolic resin has an ortho / para orientation ratio (o / p ratio) of 4 or more. The composition according to claim 1, wherein the resin (A) is a phenol-dicycloalkadiene resin. Divinyl benzenes (B) is any one composition according to claims 1-4 divinylbenzene. The composition according to any one of claims 1 to 5, further comprising a curing accelerating catalyst. The composition according to any one of claims 1 to 5, wherein the compound (C) is 2 to 50 parts by weight relative to 100 parts by weight of the total amount of the resin (A) and the compound (B). A curable resin comprising, as essential components , a resin (A) that is a novolak-type phenol resin or a phenol-dicycloalkadiene resin , divinylbenzenes (B), and a compound (C) having one maleimide structure A curable prepreg obtained by impregnating a fiber base material with a composition. A curable resin composition comprising, as essential components, a resin (A) which is a novolak-type phenol resin or a phenol-dicycloalkadiene resin, a divinylbenzene (B), and a compound (C) having one maleimide structure A compound made by kneading a fiber substrate and a filler. A curable resin composition comprising, as essential components, a resin (A) which is a novolak-type phenol resin or a phenol-dicycloalkadiene resin, a divinylbenzene (B), and a compound (C) having one maleimide structure Alternatively, a curable prepreg obtained by impregnating the fiber base material with the composition, or a cured resin product obtained by curing a compound obtained by kneading the composition with a fiber base material and a filler.