JPH07278265A - Epoxy resin composition for tow prepreg - Google Patents

Abstract

PURPOSE:To provide the title compsn. which exhibits no autohesion, is flexible, has a good deliverability from a bobbin, and gives an FRP excellent in physical properties. CONSTITUTION:This compsn. contains at least one epoxy resin selected from the group consisting of a bisphenol F epoxy resin, a bisphenol A epoxy resin liq. at 30 deg.C or lower, and a polyglycidylamine of the formula (R is H or a hydrocarbon group; and n is an integer of 1-4), dicyandiamide, and a cure accelerator as the essential components.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a tow prepreg which is excellent in paying out from a bobbin and has excellent physical properties when made into a fiber reinforced plastic (FRP).
Eg) for epoxy resin composition.

[0002]

2. Description of the Related Art Composite materials made of epoxy resin and reinforcing materials such as carbon fiber, glass fiber and aromatic polyamide fiber are excellent in specific gravity and elastic modulus, so that they are used for premier sports such as golf shafts and fishing pole tennis rackets. Application,
It is widely used in the fields of structural materials such as aircraft, civil engineering materials, and rolls.

Usually, in order to manufacture these materials, a method of laminating and curing an intermediate material called prepreg and impregnating the reinforcing material called filament winding method (F / W method) with a low-viscosity epoxy resin, It is roughly classified into a method of winding and hardening a reinforcing material on a mandrel in a predetermined pattern.

The epoxy resin used in the F / W method usually uses an acid anhydride as a curing agent, and therefore has a short pot life and requires the epoxy resin composition to be replaced daily. A tow prepreg has been proposed in order to improve this drawback, but the conventional one has a poor feeding property from the bobbin or has insufficient physical properties when made into FRP.

[0005] Tow prepreg has a fiber diameter of 5 to 5.
A resin is impregnated into a fiber bundle consisting of 1000 to 120,000 filaments of 200 μm, but since this is used by bobbin winding directly without using release paper or the like, it is not self-adhesive and flexible. Need to have sex.

As a conventionally proposed method, a method of blending a thermoplastic resin with a thermosetting resin (Japanese Patent Laid-Open No. 55-15).
870) and a method of blending a high molecular weight epoxy resin having a molecular weight of 5000 or more (Japanese Patent Laid-Open No. 58-113226), but it was insufficient to solve the above problems.

[0007]

DISCLOSURE OF THE INVENTION The present invention provides an epoxy resin composition for tow prepreg which has no self-adhesiveness, is flexible, has a good payout property from a bobbin, and has excellent physical properties when made into FRP. It is to provide things.

[0008]

Means for Solving the Problems That is, the present invention shows [A] (a) bisphenol F type epoxy resin (b) liquid bisphenol A type epoxy resin at 30 ° C. or lower and (c) general formula (1). Polyglycidyl amine type epoxy resin

[0009]

[Chemical 2] [In the formula, R is hydrogen or a hydrocarbon group, and n is an integer of 1 to 4. ] An epoxy resin composition for tow prepreg containing at least one epoxy resin selected from the above, [B] dicyandiamide and [C] curing accelerator as essential components.

The present invention will be described in detail below.

The bisphenol F type epoxy resin (a) used in the present invention is Epicoat 807 (produced by Yuka Shell Epoxy Co., Ltd.), YDF170 (produced by Toto Kasei Co., Ltd.), Epicron 830 (produced by Dainippon Ink and Chemicals Co., Ltd.), EP. -4900
(Manufactured by Asahi Denka Co., Ltd.) and PY-306 (manufactured by Asahi Ciba Co., Ltd.).

(B) 30 ° C. or lower used in the present invention,
As the bisphenol A type epoxy resin which is preferably liquid at 5 to 30 ° C., Epicoat 825 and Epicoat 82
8 (all made by Yuka Shell Epoxy Co., Ltd.) and the like.

The general formula (1) of (c) used in the present invention
The polyglycidyl amine type epoxy resin represented by is preferably a polyglycidyl amine represented by the general formula (2) and the general formula (3), and most preferably the general formulas (4), (5) and (6). Is at least one type of epoxy resin selected from the epoxy resin types, and specifically, ELM10
0 (manufactured by Sumitomo Chemical Co., Ltd.) can be mentioned.

[0014]

[Chemical 3] [In the formula, R is hydrogen or a hydrocarbon group, preferably hydrogen or an alkyl group having 1 to 10 carbon atoms, n is an integer of 1 to 4,
It is preferably an integer of 1 to 2. ]

[0015]

[Chemical 4] [In formula, R < ¹ > -R < ² > is hydrogen or a C1-C10 alkyl group, Preferably it is hydrogen or a C1-C3 alkyl group. Most preferably, it is hydrogen or a methyl group. ]

[0016]

[Chemical 5] [In formula, R < ¹ > -R < ² > is hydrogen or a C1-C10 alkyl group, Preferably it is hydrogen or a C1-C3 alkyl group. Most preferably, it is hydrogen or a methyl group. ]

[0017]

[Chemical 6] [In the formula, R ¹ is hydrogen or a methyl group, preferably a methyl group. ]

[0018]

[Chemical 7] [In the formula, R ¹ is hydrogen or a methyl group, preferably a methyl group. ]

[0019]

[Chemical 8] [In the formula, R ¹ is hydrogen or a methyl group, preferably a methyl group. The components (a), (b) and (c) may be used alone or in admixture of two or more. (A), (b) and (c)
The ratio of the components used is not particularly limited, but it is usually used in the following ratios. When two kinds of the components (a) and (b) are used, (b) 1 to 100 is added to 100 parts by weight of (a).
It is used in an amount of 5 parts by weight, preferably 5 to 30 parts by weight of (b). When two kinds of components (a) and (c) are used, it is used in an amount of 1 to 100 parts by weight, preferably 5 to 80 parts by weight, relative to 100 parts by weight of (c).
When using two types of components (b) and (c), (c)
It is used in an amount of 1 to 100 parts by weight, preferably 5 to 80 parts by weight, of (b) based on 100 parts by weight. (A),
When using three types of components (b) and (c), (a)
It is used in an amount of (b) 1 to 100 parts by weight and (c) 1 to 100 parts by weight, preferably (b) 5 to 90 parts by weight and (c) 5 to 100 parts by weight, relative to 100 parts by weight.

In the present invention, other epoxy resins can be blended as long as the effects of the present invention are not impaired. Examples of these epoxy resins include bisphenol A type epoxy resins, bisphenol S type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins which are solid at 30 ° C. or lower, and (c) above.
Other examples include glycidyl amine type epoxy resins, reactive diluents represented by glycidyl derivatives of glycerin, alicyclic epoxy resins, and the like. However, when a large amount of these epoxy resins is used, the delivery properties from the bobbin when made into a tow prepreg or the physical properties when made into an FRP are inferior, so the epoxy resins (a) and (b) of the present invention are usually used.
And 40 parts by weight or less, preferably 10 parts by weight or less, relative to 100 parts by weight of the total of the components (c).

The dicyandiamide used in the present invention is 1 to 10 parts by weight based on 100 parts by weight of the epoxy resin [A] in consideration of the curability and storage stability of the epoxy resin composition.
It is preferably used in the range of 2 to 8 parts by weight.

As the curing accelerator used in the present invention, a urea derivative is generally used. Specific preferred urea derivatives include phenyldimethylurea and 3- (4
Chlorophenyl) -1,1 dimethylurea, 3- (3,
4 dichlorophenyl) -1,1 dimethylurea (DCM
U). The amount used is 1 to 10 parts by weight, preferably 2 to 8 parts by weight with respect to 100 parts by weight of the epoxy resin [A] in consideration of the curability and storage stability of the epoxy resin.

There are no particular restrictions on the method of mixing the components of the present invention. Usually, dicyandiamide and a curing accelerator are used in a state of being dispersed in an epoxy resin.

The method of impregnating the tow with the epoxy resin composition of the present invention is not particularly limited, but the resin bath of the epoxy resin composition is impregnated with the tow in order to adjust the impregnation amount, and then the amount of resin adhered through the orifice is adjusted. Or a method of controlling the amount of resin adhered by passing the tow on a rotating drum having a doctor blade impregnated with a resin bath. Further, in order to facilitate the impregnation, it is also preferably used to appropriately heat at the curing temperature or lower.

FR using the epoxy resin composition of the present invention
The reinforcing material used for producing P is not particularly limited, but examples thereof include carbon fiber, glass fiber, aromatic polyamide fiber, boron fiber, silicon carbide fiber, alumina fiber, potassium titanate fiber, and the like. To be

[0026]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

Example 1 Bisphenol F type epoxy resin (Epicoat 807)
4 parts by weight of dicyandiamide and 100 parts by weight of DCM
U6 parts by weight were mixed. This resin composition was impregnated with 6000 filaments of carbon fiber T300 manufactured by Toray Industries, Inc.
After passing through a hot roll heated to 50 ° C. through an orifice of mm, it was wound on a bobbin. The resin content at this time was 40 wt%. This tow prepreg was put on the F / W device, and when it was fed out from the bobbin at a speed of 20 m / min, good work could be performed, and the mandrel could be wound in a predetermined pattern without thread breakage during F / W operation. It was

Further, the tows of this tow prepreg were arranged in one direction on a drum winder to form a sheet of prepreg, which were laminated in an autoclave and defoamed under reduced pressure.
It heated at 0 degreeC for 1 hour, and obtained the unidirectional laminated board with a fiber content rate of 60 vol%. The physical properties of this sheet at 25 ° C are 0 °
Bending strength 140 kgf / mm ² , 0 ° bending elastic modulus 13.
0tf / mm ² , interlaminar shear strength (ILSS) 9 kgf /
It was mm ² .

Example 2 100 parts by weight of a bisphenol A type epoxy resin (Epicoat 828) which was liquid at 30 ° C. or lower was mixed with 5 parts by weight of dicyandiamide and 3 parts by weight of DCMU, and the same carbon fiber as in Example 1 was used. Similarly, tow prepreg was obtained. This tow prepreg was put on the F / W device, and when it was fed out from the bobbin at a speed of 20 m / min, good work could be performed, and the mandrel could be wound in a fixed pattern without thread breakage during F / W work. It was

A unidirectional laminate was obtained using the tow prepreg in the same manner as in Example 1. The physical properties of this sheet at 25 ° C. are 0 ° bending strength 135 kgf / m
m ² , 0 ° bending elastic modulus 13.0 tf / mm ² , ILSS
It was 8 kgf / mm ² .

Example 3 Polyglycidylamine type epoxy resin (ELM100)
6 parts by weight of dicyandiamide and 100 parts by weight of DCM
U 4 parts by weight were mixed and the same carbon fiber as in Example 1 was used to obtain a tow prepreg in the same manner as in Example 1. This tow prepreg is put on the F / W device, and 20m / mi from the bobbin.
Good work can be performed when it is fed out at a speed of n, and F / W
I was able to wind the mandrel in a fixed pattern without breaking the thread during operation.

Further, using this tow prepreg, a unidirectional laminate was obtained in the same manner as in Example 1. The physical properties of this sheet at 25 ° C. are 0 ° bending strength 140 kgf /
mm ² , 0 ° bending elastic modulus 13.0 tf / mm ² , ILS
It was S10 kgf / mm ² .

Example 4 Bisphenol F type epoxy resin (Epicoat 807)
Dicyandiamide 5 was added to 80 parts by weight and 20 parts by weight of liquid bisphenol A type epoxy resin (Epicoat 825).
Parts by weight and 7 parts by weight of DCMU were mixed. This resin composition was dipped in a resin bath, and 6000 filaments of carbon fiber M40J manufactured by Toray Industries, Inc. were passed on a rotating drum having a distance of 0.15 mm from a doctor blade, and after passing through a hot roll heated to 50 ° C., I wound it up on a bobbin. The resin content at this time was 40 wt%. This tow prepreg is put on the F / W device, and 20m / mi from the bobbin.
Good work can be performed when it is fed out at a speed of n, and F / W
I was able to wind the mandrel in a fixed pattern without breaking the thread during operation.

Further, using this tow prepreg, a unidirectional laminate was obtained in the same manner as in Example 1. The physical properties of this sheet at 25 ° C. are 0 ° bending strength 115 kgf / m
m ² , 0 ° bending elastic modulus 19.5 tf / mm ² , ILSS
It was 8 kgf / mm ² .

Example 5 Bisphenol F type epoxy resin (Epicoat 807)
50 parts by weight and polyglycidylamine type epoxy resin polyglycidylamine type epoxy resin (ELM100)
50 parts by weight of dicyandiamide 4 parts by weight and DCMU
6 parts by weight were mixed and the same carbon fiber as in Example 4 was used to obtain a tow prepreg in the same manner as in Example 4. This tow prepreg is put on the F / W device, and 20 m / min from the bobbin.
The work was carried out satisfactorily when unrolled at the speed of, and the mandrel could be wound in a predetermined pattern without causing thread breakage during the F / W operation.

Further, using this tow prepreg, a unidirectional laminate was obtained in the same manner as in Example 1. The physical properties of this sheet at 25 ° C. are 0 ° bending strength 115 kgf / m
m ² , 0 ° bending elastic modulus 19.5 tf / mm ² , ILSS
It was 9 kgf / mm ² .

Example 6 Liquid bisphenol A type epoxy resin (Epicoat 82
5) Dicyandiamide 5 in 45 parts by weight and 55 parts by weight of polyglycidylamine type epoxy resin (ELM100)
By weight and 6 parts by weight of DCMU were mixed, and using the same carbon fiber as in Example 4, a tow prepreg was obtained in the same manner as in Example 4. This tow prepreg was put on the F / W device, and when it was fed out from the bobbin at a speed of 20 m / min, good work could be performed, and the mandrel could be wound in a predetermined pattern without thread breakage during F / W operation. It was

Further, using this tow prepreg, a unidirectional laminate was obtained in the same manner as in Example 1. The physical properties of this sheet at 25 ° C. are 0 ° bending strength 115 kgf / m
m ² , 0 ° bending elastic modulus 19.5 tf / mm ² , ILSS
It was 9 kgf / mm ² .

Example 7 Bisphenol F type epoxy resin (Epicoat 807)
35 parts by weight, 30 parts by weight of liquid bisphenol A type epoxy resin (Epicoat 828) and 35 parts by weight of polyglycidyl amine type epoxy resin (ELM100) were mixed with 6 parts by weight of dicyandiamide and 5 parts by weight of DCMU,
Using the same carbon fiber as in Example 4, a tow prepreg was obtained in the same manner as in Example 4. This tow prepreg was put on the F / W device, and when it was fed out from the bobbin at a speed of 20 m / min, good work could be performed, and the mandrel could be wound in a predetermined pattern without thread breakage during F / W operation. It was

Using this tow prepreg, a unidirectional laminate was obtained in the same manner as in Example 1. The physical properties of this sheet at 25 ° C. are 0 ° bending strength 115 kgf / m
m ² , 0 ° bending elastic modulus 19.5 tf / mm ² , ILSS
It was 9 kgf / mm ² .

Example 8 Bisphenol F type epoxy resin (Epicoat 807)
70 parts by weight, 10 parts by weight of liquid bisphenol A type epoxy resin (Epicoat 828) and 20 parts by weight of polyglycidylamine type epoxy resin (ELM100) were mixed with 6 parts by weight of dicyandiamide and 5 parts by weight of DCMU,
Using the same carbon fiber as in Example 4, a tow prepreg was obtained in the same manner as in Example 4. This tow prepreg was put on the F / W device, and when it was fed out from the bobbin at a speed of 20 m / min, good work could be performed, and the mandrel could be wound in a predetermined pattern without thread breakage during F / W operation. It was

Further, using this tow prepreg, a unidirectional laminate was obtained in the same manner as in Example 1. The physical properties of this sheet at 25 ° C. are 0 ° bending strength 115 kgf / m
m ² , 0 ° bending elastic modulus 19.5 tf / mm ² , ILSS
It was 9 kgf / mm ² .

Comparative Example 1 Liquid bisphenol A type epoxy resin (Epicoat 82
8) 50 parts by weight and solid bisphenol A type epoxy resin (Epicoat 1001, manufactured by Yuka Shell Epoxy Co., Ltd.)
After heating and mixing 50 parts by weight at 100 ° C., 5 parts by weight of dicyandiamide and 3 parts by weight of DCMU were dispersed and mixed to obtain a resin composition. The same carbon fiber as in Example 1 was used in this composition, the resin composition was heated to 50 ° C. and impregnated, and a tow prepreg was obtained in the same manner as in Example. When I tried to take out this tow prepreg from the bobbin, the T300 was 5m / min from the bobbin because the resin was too sticky.
When it was fed at the speed of, a thread breakage occurred.

[0044]

As is clear from the results of the above Examples and Comparative Examples, by impregnating the reinforcing material with the epoxy resin composition of the present invention, it has flexibility without self-adhesiveness,
In addition, a tow prepreg is obtained which has a good paying-out property from the bobbin and has the physical properties of the FRP that fully exhibit the performance of the reinforcing material.

Claims (1)

[Claims] 1. [A] (a) Bisphenol F type epoxy resin (b) Liquid bisphenol A type epoxy resin at 30 ° C. or lower and (c) Polyglycidylamine type epoxy resin represented by the general formula (1) 1] [In the formula, R is hydrogen or a hydrocarbon group, and n is an integer of 1 to 4. ] The epoxy resin composition for tow prepregs which contains at least 1 type of epoxy resin selected from these, [B] dicyandiamide, and [C] a hardening accelerator as an essential component.