JPH02124919A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. with excellent storage stability, moist heat resistance and compression characteristics after impact test by incorporating bifunctional and trifunctional epoxy resins, a specified phenol compd. and 4,4'- or 3,3'-diaminodiphenyl sulfone as the essential components. CONSTITUTION:A bifunctional epoxy resin which is pref. bisphenol A and/or F epoxy resins, a trifunctional epoxy resin which is pref. one or more of N,N,O- triglycidyl-p- or -m-aminophenol, N,N,O-triglycidyl-4-amino-m- or -5-amino- o-cresol and 1,1,1-(triglycidyloxyphenyl)methane, a phenol compd. of formula I, II or III (wherein X1-4 are each H, Br, Cl, a 1-8C alkyl and one or more 1-8C alkyls is essential) and 4,4'- or 3,3'-diaminodiphenyl sulfone are incorporated as the essential components.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an epoxy resin composition for prepregs that provides excellent storage stability, moisture and heat resistance, and impact resistance and compression properties. The resulting composite material can be used in aircraft, automobiles, and general industrial applications.

[Conventional technology]

Conventionally, epoxy resin has been widely used as an IJ resin for composite materials due to its adhesive properties and high rigidity. Among them, N, N, group N'-tetraglycidyldiaminodiphenylmethane, 4 are used as matrix resins for high-performance structures.
．． Compositions based on 4'-diaminodiphenylsulfone have been in use for many years since 1972.

[Problem that the invention seeks to solve]

However, since the elongation of IJ x balance is low, recent elongation reinforcing fibers such as charcoal having a breaking elongation of 1.5% or more have been used. It had the disadvantage that it could not follow ``1g fiber, aramid fiber, glass fiber, etc., and its tensile elongation was lower than that of reinforcing fiber.As a result, the compressive strength after being sucked was low in the temperature range of 82℃. However, the compressive strength after impact was extremely low, and the material was completely unsatisfactory for use as a material for secondary structures.

10,000 th SAMPE European Cha
pter (1984) Paper 15 (T, T
Materials with high compressive strength after impact have been reported, but the compressive strength after moisture absorption is insufficient, and the fiber volume is low due to the inclusion of an intermediate layer called interleaf. The Af rate did not increase, and it was far from being practical.

In view of the above, the present inventors have determined that the compressive strength in the 82°C temperature range after moisture absorption (110 Y/- or more) and the compressive strength (27 k
l? The present invention has been arrived at as a result of intensive studies regarding an embossed fat composition for prepregs that provides superior properties in all of the above).

[Means for solving problems]

That is, the main purpose of the present invention is ^ Bifunctional epoxy resin CB) Pentafunctional epoxy shield (C) Phenol compound represented by the following formula (However, X
X4 represents H, Br, C1, an alkyl group having 1 to 8 carbon atoms, which may be different or different, but at least
(D) An epoxy side fat composition containing 4.4'-diaminodiphenylsulfone or 3°3'-diaminodiphenylsulfone as an essential component.

Of these compositions, some or all of (A), all of (B), and all of (CJ) are prepared in advance (C).
It is preferable to pre-react 80% or more of the 7-enolic OH of (A) with the epoxy group of (A).

The present invention further provides an epoxy resin composition containing reinforcing fibers in the epoxy resin composition.

Examples of the (8) bifunctional epoxy resin used in the present invention include bisphenol AW epoxy resin, bisphenol F type epoxy resin, brominated epoxy resins thereof, and bisphenol 8g epoxy resin.

In order to improve toughness, it is desirable to use bisphenol A type epoxy resin or bisphenol F type epoxy resin as the main component.

The molar ratio of epoxy groups to epoxy resin (B) in these epoxy resins is A/B=l/α1~I/1.
2, preferably 1/α2 to 1/1.0. 1
If it is larger than /α1, not only hot water resistance but also chemical resistance will decrease, which is not preferable. If it is less than I/1.2, the toughness is insufficient, the utilization rate of the reinforcing material is lowered, and the compressive strength after impact is lowered, which is not preferable.

The trifunctional epoxy resin (B) used in the present invention includes N,N,O-triglycidyl-p- or -m-aminophenol, N,N,O-)liglycidyl-4-amino-m- or -5-amino-0-cresol, 1. Chi1-
(Triglycidyloxyphenyllamethane, etc. are mentioned. Among them, N, N.

0-)! j Glycidyl compounds are preferably used from the viewpoint of improving solvent resistance.

As the phenolic compound (C) used in the present invention, compounds represented by the following formula can be used alone or in combination.

It is also possible to use other phenol compounds in combination within a molar ratio not exceeding 50%. Main representative examples of other phenol compounds include tetrabromo bisphenol A1 tetrabromo bisphenol F1 octabromo bisphenol A1 bisphenol A1 bisphenol F1 bisphenol S1 tetrabromo bisphenol S1 bis-(!1.5-dimethyl-4-
hydroxyphenyl)methane, bis-(A-methyl-4
-hydroxyphenyl]methane, 4,4'-(p-)unilene diisopropylidene)bis-(2,6-xylenol), and the like.

When using a mixture of phenol compounds in this manner, it is necessary to set the quantitative ratio of the phenol compounds so that the following formula is satisfied as a whole.

(However, XI-'-X4 represents H, Br, ct, an alkyl group having 1 to 8 carbon atoms, and may be equal or different, but at least one is an alkyl group having 1 to 8 carbon atoms. ) Specific representative examples thereof include 2,5'-dimethylhydroquinone, 2,6-dimethylhydroquinone, and 2,5-dimethylhydroquinone.
Di-tθrt-amylhydroquinone, 2.5-dit
ert-butylhydroquinone, 2.5-') -t
art-hexylhydroquinone, 2-inglobylhydroquinone, 2-ethyl-5-methylhydroquinone, 2,3,5.6-tetramethylhydroquinone, 2,
4.6-Trimethylresorcinol, 4-1-butylcatechol, etc. may be mentioned.

It is preferable to use the amount of (C) in a ratio of 1/α1 to 1/α9. If this ratio is larger than 1/α1, sufficient heat and humidity properties and impact resistance cannot be obtained, so it is not appropriate; If it is smaller than /α9, heat resistance and solvent resistance will decrease, which is not preferable. More preferably 1
/α2~+/Q, 8.

(It is desirable that the amount of DJ used satisfies the following formula.

(Number of moles of epoxy group H) - (Number of moles of phenolic OH) Amine (Number of moles of auxiliary NH = 1/α8~+/1.5 A more preferable ratio is 1/α9~1/1゜2. be.

If it is larger than 1/α8, curing is insufficient and solvent resistance,
Poor heat resistance, +/1. If it is smaller than s, the water resistance and solvent resistance will decrease, making it difficult to stick.

Further, all or part of the epoxy resin (A), all of the epoxy resin (B), and all (Q) are reacted in advance with 80% or more, preferably 90% or more of the phenolic OH. It is preferable.

If the reaction rate is lower than this, the impact resistance of the resin composition will decrease, so it is preferable to pre-react to the above-mentioned extent.

Epoxy group molar ratio A / B = 1/α5 of some or all epoxy resins (A) and all epoxy resins C) used in the preliminary reaction with the phenol compound (C)
It is 1/50, preferably 1/α5 to 1/2.0. If it is larger than 1/α3, sufficient hot water resistance and solvent resistance cannot be obtained and it is not suitable.

If it is smaller than 1/mu0, gelation will occur during the preliminary reaction, which is not preferable.

In addition, t of (C) used in the preliminary reaction is the sum of the moles of the epoxy group in (B) and the number of moles of the phenolic OH in (C) = l / (L 2 ~ + / 1.1, more preferably Fi, 1/1L3~1/i
, O.

If it is larger than 1/α2, sufficient hot water resistance and compressive strength after impact cannot be obtained, which is not preferable. Moreover, if it is smaller than 1/11, the viscosity during preliminary reaction will be high and handling properties will be difficult, which is not preferable.

The epoxy resin composition of the present invention has the above (A) to q acid components as basic essential components, but other epoxy resins (6) may be added within a range that does not disrupt the overall physical property balance.
It is also possible to use them together. Other epoxy resins (
Typical examples include tetrafunctional epoxy resins such as N, N, N; N'-tetraglycidyldiaminodiphenylmethane;
You can buy novolak epoxy resin. The amount of these (Enoki components) used is preferably less than 20i of the total epoxy m fat components (B+(B)+(6)).
(When using force components, it is desirable that the ratio of each component satisfies the following formulas.

(A)/(Molar ratio of epoxy groups in B2 = 1/α1-1
/1.2I (L) approx. 1-1 (1) molar The resin composition of the present invention contains inorganic photonic agents such as silica powder, Aerosil, microballoons, and flame retardants as other components. In addition to antimony trioxide, so-called elastomer components such as butadiene-acrylonitrile copolymer with carboxyl groups at both ends, and thermoplastic resin components such as polyethersulfone, polysulfone, polyetheretherketone, polyetherimide, and polyvinyl butyralide. It is permissible to use these other components in combination as required.The amounts of these other components to be used may be appropriately set according to the purpose within a range that does not disrupt the overall physical property balance.

Resin composition Fi4.4'-diaminodiphenylsulfone (4,4'-DDS) or 3°5 in the present invention
'-Diaminodiphenylsulfone (A,5'-DDS
) in the above-mentioned ratios, sufficient curing can be achieved, but other curing agents or curing accelerators may be used in combination.

Typical examples of other curing agents include aromatic amines such as 4,4'-diaminodiphenylmethane and trimethylene-bis(4-aminobenzoate), and dicyandiamide. The amount of these other curing agents used is desirably kept at 20% by weight or less of the total amount of curing agents.

A typical example of the curing accelerator is amine salt of boron 37 fluoride. The amount of the curing accelerator to be used may be appropriately determined depending on the purpose.

Examples of reinforcing fibers include carbon fibers, glass fibers, aramid fibers, boron fibers, silicon carbide fibers, and the like.

The reinforcing fibers can also be used in the form of milled fibers, chopped fibers, unidirectional sheets, or woven fabrics.

〔Example〕

The present invention will be specifically explained below using Examples.

Parts represent parts by weight. Moreover, the molar ratio represents the molar ratio of functional groups.

The properties of the composite material were determined by the following measurement method.

It was settled that the measurement result was 60%.

"Hot water resistance" is 0° 16 layer laminated material composite is 7
After being left in water at 1°C for 14 days, A8TM D-6
It was determined by a compression test in the 00 direction at 82°C in accordance with 95.

"Impact resistance" is based on NASA RP 1092, and the panel size is 4" x 6#. It is fixed on a board with a 5' x 5" hole, and a 1/2" R nose is attached in the center. After dropping a 4.9k!9 weight with a weight on it and applying an impact of ts o tb・1n per inch of plate thickness,
This was determined by subjecting the panel to a compression test.

"Resin handling properties" were determined by the softness of the resin composition at room temperature. Soft items were rated 0 and hard items were rated x.

"MEK resistance" is determined by the change in the appearance of the cured resin after immersion at room temperature for 7 days.
And so.

Example 1 Bisphenol F type epoxy resin, Epicote 807 (
Yuka Shell Epoxy Co., Ltd. trade name, epoxy equivalent 170
) 100 parts, N,N,O-)liglycidyl-p-aminophenol (epoxy equivalent weight 94) 1&tS parts, 2.5-
Di-tert-butylno-hydroquinone 17.0 parts, 4
．． 4'-D D S 57.9 parts were mixed, and further 1.25 parts of silicon oxide fine powder (Aeroai/1580, manufactured by Nippon Aerosil Co., Ltd.) was added, and the mixture was thoroughly mixed in a kneader at 60°C to obtain a resin composition. Product (1) was obtained. This composition was sandwiched between glass plates to form a 2W plate and cured at 180°C for 2 hours to obtain a resin plate. Further, this resin composition (1) is impregnated into carbon fibers aligned in one direction (Pyrofil M-1, trademark manufactured by Mitsubishi Rayon Co., Ltd.) by a hot melt method,
A unidirectional prepreg with a thread weight of 145 t/m" and a resin content of 35% by weight was created. This prepreg was
ls and [+45°10°/-45°/90°] 4θ quasi-isotropic nucleation layer, and was cured at +BOC for 2 hours to obtain a composite material. The test results for these are shown in Table 1.

Examples 2 to 6, Comparative Examples 1 to 6 Tests were conducted by changing the stoichiometry of the compounds used in Example 1 as shown in Table 1. The results are listed in Table 1.

Examples 7 to 16 Implementation? The test was conducted by changing the compounds used in IJ1 as shown in Table 1. The results are also shown in Table 1.

The compound Epicote 828 used is a bifunctional epoxy resin (bisphenol A diglycidyl ether type epoxy, trade name manufactured by Yuka Shell Epoxy Co., Ltd., 1 ae to 1 epoxy).

Example 17 The composition of Example 1 was used, but Epikote 807 was divided into two parts and a portion was pre-reacted. That is, 50 parts of Epicote 807, N, N.

0-) liglycidyl-p-7 minofukonol 1 & 6 parts,
2.5-di-tert-butylhydroquinone 17.0
After reacting at 130°C for 2 hours, cooling to 60°C,
Remaining Epicote 80770 parts, 4.4'-DDS
57.9 parts of silicon oxide fine powder was added thereto, and 1.25 parts of fine silicon oxide powder was added thereto and thoroughly mixed in a kneader (kneaded at 60°C) to obtain a resin composition (II). Resin plates and composites were tested in the same manner as in Example 1, except that this composition (11) was used in place of composition (1). The results are shown in Table 2.

Examples 18-24 Example f! except that the stoichiometry and reaction rate of the compounds used in the preliminary reaction were changed as shown in Table 2. The test was conducted in the same manner as A117. The results are shown in Table 2.

Example 25 A test was conducted in exactly the same manner as in Example 1, except that 110 parts of powdered polyether sulfone was further mixed with each compound described in Example 1.

The handleability of the resulting composition and the MEK resistance of the cured resin were both good, and the degree of pressure reinforcement after water absorption at 82°C of the carbon fiber composite material manufactured using this resin composition was +21 kg.
/vts” Compressive strength after impact at room temperature 35kg/■
2 and the physical properties as a composite material were also extremely good.

Claims (1)

[Claims] 1. An epoxy resin composition characterized by containing the following components (A), (B), (C), and (D) as essential components (A) a bifunctional epoxy resin (B) a trifunctional epoxy Resin (C) Phenolic compound represented by the following formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas, chemical formulas,
There are tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, X_1 to X_4 are H, Br, Cl, carbon number is 1
(D) 4,4'-diaminodiphenylsulfone or 3,
3'-diaminodiphenylsulfone 2, composition 3 according to claim 1, characterized in that (A) the bifunctional epoxy resin is a bisphenol A type and/or bisphenol F type epoxy resin, (B) a pentafunctional epoxy resin is N,N,O-triglycidyl-p- or -m-aminophenol, N,N,O
-Triglycidyl-4-amino-m- or -5-amino-o-cresol, 1,1,1-(triglycidyloxyphenyl)methane or a mixture of two or more thereof. Composition 4 according to 1, the molar ratio of epoxy groups (A)/(B) is 1/0.1
Composition 5 according to claim 1, characterized in that the ratio is 1/1.2 to 1/1.2, preferably 1/0.2 to 1/1.0, and the amount of (C) used satisfies the following formula: The composition according to claim 1, characterized in that the sum of the number of moles of epoxy groups in (A) and (B)/the number of moles of phenolic OH in (C) = 1/0.1 to 1/0.9 6, The composition according to claim 1, characterized in that the amount of (D) used satisfies the following formula {(sum of moles of epoxy groups in (A) and (B))-((
Number of moles of phenolic OH in C)}/Number of moles of NH in amine (D) = 1/0.8 to 1/1.5 7, some or all (A) and all (B)
and all (C), beforehand the phenolic OH of (C)
Composition 8 according to claim 1, characterized in that 80% or more of the epoxy groups of (A) and (B) are pre-reacted and used. Composition 9 according to claim 7, characterized in that the molar ratio of is 1/0.3 to 1/3.0, and the amount of (C) used in the preliminary reaction satisfies the following formula: The composition according to claim 7, characterized in that the sum of the number of moles of epoxy groups in (A) and (B)/the number of moles of phenolic OH in (C) = 1/0.2 to 1/1.110
The composition according to claim 1, characterized in that it contains reinforcing fibers.