JPH02127420A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition excellent in storage stability, moist heat resistance and post-impact compression characteristics and useful for a prepreg by blending a bifunctional epoxy resin, trifunctional epoxy resin and respectively specified phenol compound and diaminodiphenyl sulfone. CONSTITUTION:(A) A bifunctional epoxy resin (preferably bisphenol A type or bisphenol F type), (B) a trifunctional epoxy resin (preferably N,N,O- triglycidyl-p-or m-amiophenol, etc.), (C) a phenol compound [e.g., 2,2'- methylenebis(4-methyl-6-t-butylphenol)] of the formula (X1 to X8 are H, Br, Cl, 1-8C alkyl or OH, provided that one of X1 to X4 and one of X5 to X8 are OH; Y1 and Y2 are H, Br, Cl or 1-8C alkyl; Z is -O-, -S-, -SO2-, -C(R)(R') (R is H, 1-8C alkyl or phenyl)] and (D) 4,4'-diaminodiphenyl sulfone or 3,3'- diaminodiphenyl sulfone are blended, thus obtaining the objective composition.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an epoxy resin composition for prepregs that provides vague storage stability, moist heat resistance properties, and impact resistance and compression properties, and relates to the resin composition. The composite materials obtained from this process can be used in aircraft, automobiles, and general industrial applications.

[Conventional technology]

Conventionally, epoxy resins have been widely used as matrix resins for composite materials due to their seamability and high rigidity. Among them, flN, N, N', and N are used as matrix resins for high-performance structures.
'-tetraglycidyldiaminodiphenylmethane, 44
Compositions containing '-diaminodiphenylsulfone as a main component have been widely used since 1972.

[Problem that the invention seeks to solve]

However, since the elongation of the matrix resin is small, the composite material obtained by heating and curing the prepreg of this composition cannot be used with recent high elongation reinforcing fibers such as carbon fibers, aramid fibers, and f having a breaking elongation of t5% or more. It had drawbacks such as being unable to follow lath fibers and the like, and its tensile elongation was lower than that of reinforcing fibers. As a result, after moisture absorption +2) Ff:, - strength r
Although it was sufficient in the temperature range of 82° C., the compressive strength after impact was extremely low, and the material was completely inadequate for use as a material for secondary structures.

On the other hand s th Japan AMPK European
Chapter (1984) Paper 15
(Tattersall) has also reported materials with high compressive strength after impact, but the compressive strength after moisture absorption was insufficient). The volume content did not increase, and it was far from practical.

In view of the above, the present inventors determined the compressive strength in the 82°C temperature range after moisture absorption (110 to 718 or more) and the compressive strength after impact (27
As a result of intensive studies, the present invention was developed regarding an epoxy resin composition for prepregs that provides superior properties in terms of both (kcg/- or more).

[Means for solving problems]

That is, the gist of the present invention is c) Bifunctional epoxy resin CB) Pentafunctional epoxy resin (0) Phenol compound CX, ~X represented by the following formula
, is H, Br, Ot, an alkyl group having 1 to 8 carbon atoms, or one of -011, X, ~X, and one of X, ~X is -OH.

"1 # Y* is B, Br, Ol or carbon number 1-8
an alkyl group OR (where R represents an alkyl group having 1 to 8 carbon atoms or a phenyl group) Φ) 44'-diaminodiphenylsulfone or hahe3'-
An epoxy resin composition containing diaminodiphenylsulfone as an essential component.

Of these compositions, some or all (A), all ω), and all (C) are preliminarily mixed with 80% or more of the phenolic 0111 of (0) in the epoxy resin of (A) and (B). It is preferable to use it after pre-reacting with a group.

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

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

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

The molar ratio of epoxy groups to epoxy resin (B) in these epoxy resin bodies is M/Ez 1/CL
1 to 1/12, preferably 1/[lL2 to 1/l
It is O. If it is larger than 1/11, it is not preferable because not only hot water resistance but also chemical resistance is reduced. 1/
If it is smaller than 12, the toughness will be insufficient, the utilization rate of the reinforcing material will be lowered, and the compressive strength after 1 jtr impact will be lowered, which is not preferable.

The trifunctional epoxy resin @) used in the present invention is as follows:
M,N,O-triglycidyl-p- or -m-aminophenol, N,N,O-triglycidyl-4-amino-
m- or -5-amino-〇-cresol%1. L1-(
) liglycidyloxyphenyl) methane, and the like. Among them, kLLO-)IJ glycidyl compounds are preferably used from the viewpoint of improving solvent resistance.

The phenol compound (0) used in the present invention is 2
．． 2'-methylenebis(4-methyl-6-tartbutylphenol), 2.2'-methylenebis(4-ether-6-tertbutylphenol), 2.4'-ethyrite/bisphenol, l''-bisphenol As 2
．． 2'-/tyrenebisC4-)fsiphenol 32.2
'-methylenebis(4-tartbutylphenol) and the like can be cited as substitutes.

The amount of (C) to be used is preferably such that the ratio of the number of moles of phenolic 0 in (C) is 1/α1 to 1/α9, and if this ratio is greater than f/0.1, sufficient heat and humidity properties are achieved. If it is smaller than 1/α9, heat resistance and solvent resistance will decrease, which is not preferable. More preferably it is 1/(12 to 1/α8).

It is desirable that the usage amount of CD) satisfies the following formula.

ccA>sum of moles of epoxy groups) - (number of moles of phenolic 080 of (0)) number of moles of ME of amine = s1/(18~1/L5) A preferred ratio is 1/ α9 to 1/12.

If 1/α8 is too large, curing will be insufficient, solvent resistance,
Heat resistance is poor, and if it is smaller than 1/15A, water resistance and solvent resistance will decrease, which is not preferable.

In addition, it is preferable that all or a part of the epoxy resin (), all of the epoxy resin @), and all U be reacted in advance with 80% or more of the phenolic OR, more preferably with 9 (196 or more). .

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.

Part or all of the epoxy resin body used for pre-curing with the phenol compound (0)), epoxy resin CB) O epoxy group molar ratio A/B = 1/α3~
1/50, good luck tfi, 1/l 5~1/
It is 2.0. If it is larger than 1/α3, it will have sufficient hot water resistance.
Solvent resistance is not obtained and it is not suitable.

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

Further, the amount of (C) used in the preliminary reaction is preferably set to the number of moles of phenolic OH in (C) = 1/(L2 to 1/11, more preferably 1/α3 to 1/lO). If it is larger than 1/(L2), sufficient hot water resistance and compressive strength after impact cannot be obtained, which is undesirable. If it is smaller than 1/11, the viscosity during preliminary reaction will be high, making it difficult to handle the mixture. .

The epoxy resin composition of the present invention has the above-mentioned components) to Φ) as basic essential components, but it is also possible to use other epoxy resins @) in combination without disturbing the overall physical property balance. . Other epoxy resins@)
Typical examples include tetrafunctional epoxy resins such as L 1i, s', s'-tetraglycidyldiaminodiphenylmethane, and novolac type epoxy resins. The amount of these components used is preferably not more than 20 parts by weight of the total epoxy resin fraction ((4) 10 parts + 10 parts by weight).

In addition, it is desirable that the ratio of each component in the case where (to)) components are used satisfies the following formulas.

Molar ratio of epoxy 1 in (A)/ω) = 1/[11~
1/12 (0) + 2) Near z/-r property 0H (0 moles
0. l [IL9 amine (Nu mole number α8 t, 5) The resin composition of the present invention may contain other components such as inorganic photonic agents such as silica powder, Aerosil, microballoons, and antimony dioxide as a flame retardant. In addition, so-called elastomer components such as butadiene-acrylonitrile copolymer with carboxyl groups at both ends, thermoplastic resin components such as polyethersulfone, polysulfone, polyetheretherketone, polyetherimide, and polyvinyl butyralide may be used in combination depending on the purpose. The amount of these other components to be used may be appropriately determined according to the purpose within a range that does not disrupt the overall balance of physical properties.

The resin composition of the present invention can be sufficiently cured by using 44'-diaminodiphenylsulfone (44'-DD8) or 45'-diaminodiphenylsulfone (45'-DD8) in the above-mentioned ratio. However, other curing agents or curing accelerators may be used in combination.

Typical examples of other curing agents include aromatic amines such as tr14.4'-diaminodiphenylmethane and trimethylene-bis(4-aminobenzoate), and dicyandiamide. It is desirable that the use of these other curing agents be limited to less than 20 weight plates of the total amount of curing agents.

A typical example of the curing accelerator is an amine salt of boron trifluoride. 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, 75-mid fibers, boron fibers, and silicon carbide fibers.

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 with reference to 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.

The measurement results were converted to a fiber volume content of 60%.

"Hot Water Resistance"#-1l: After leaving the 0616-layer laminated material composite in water at 71℃ for 14 days, 80TM
It was determined by a compression test in the 0° direction at 82°C according to D-695.

"Impact resistance" is based on NMU SA RP 1092, and a board with panel dimensions 4#X and S# is fixed on a stand with a 3'X5' hole, and the nose of A'R is placed in the center. Drop mk for 49 yen applied, plate thickness 1 inch equivalent 1 s
It was determined by subjecting the panel to a compression test after applying o o tb.1no impact.

"Resin handling properties" were determined based on the softness of the resin composition at room temperature. Soft items were rated ○, and hard items were rated ×.

"MIX resistance" is determined by the change in the appearance of the cured resin product after immersing it at room temperature for 7 days.
And so.

Example 1 Bisphenol P-type epoxy resin, Ehi=r-to 80
7 (Yuka Shell Epoxy Co., Ltd. product name, epoxy fi
170) 100 parts, "e"eO-triglycidyl-p-
Amine phenol (Ebogishi equivalent weight 94) 16 [parts, 2.
261 parts of 22-methylenebis(4-methyl-6-tart-butylphenol) and 837.9 parts of ζ4'-DD were mixed, and silicon oxide fine powder (Erosil 380
, Nippon Aerosil Co., Ltd.) t25 parts was added, and the mixture was heated at 60°C.
The mixture was thoroughly mixed in a kneader to obtain a resin composition (1). This composition was sandwiched between two glass plates, 18
It was cured at 0° C. for 2 hours to obtain a resin plate. In addition, carbon fibers (Pyrofil M) made by aligning this resin composition (1) in one direction
-1, made by Mitsubishi Rayon Co., Ltd.) impregnated by hot melt method, yarn weight 1452/m8 resin content 55
A unidirectional prepreg of % by weight was prepared. This prepreg [0°] 3. and [+45°10'/-a s'
/90°〕1. The materials were laminated in a quasi-isotropic manner and cured at 180° C. for 2 hours to obtain a composite material.

The test results for these are shown in Table 1.

Experimental rows 2 to 6, Comparative rows 1 to 6 The tits of the compounds used in Example row 1 were changed as shown in Table 1 and the test was conducted. The results are also shown in Table 1.

Examples 7 to 16 Compound 7fc used in Example Example 1 The test was conducted with the changes shown in Table 1. The results are shown in Table 1.

The compound Epicoat 828 used is a bifunctional epoxy resin (bisphenol diglycidyl ether type epoxy, part name manufactured by Yuka Shell Epoxy Co., Ltd., epoxy resin).
1BB).

Practical row 17 Although the bottom of practical row 10 was used, Epikote 807 was divided into two parts and a portion was pre-reacted before use. That is, 30 parts of Epicote 807, 146 parts of LLO-triglycidyl-p-aminophenol, 2,2'-methylene-bis(
4-methyl-6-tert-butylphenol) 2 parts 1
After reacting at 130°C for 2 hours, it was cooled to 60°C.
7.9 parts of silicon oxide fine powder was added thereto, and 25 parts of silicon oxide fine powder was further added thereto and mixed well in a kneader (kneaded at 60°C) to obtain a resin composition (If). Resin plates and composites were tested in the same manner except that this composition (11) was used as a substitute for composition (1) in Example 10. The results are shown in Table 2.

Actual rows 18 to 24 The test was carried out in the same manner as in Example 17, except that the theory of the compounds used in the preliminary reaction and the reaction rate were changed as shown in Table 2.

The results are shown in Table 2.

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

The handleability of the obtained composition and the MEK resistance of the cured resin product are both good, and the pressure linear strength after water absorption at 82°C of the carbon fiber composite material manufactured using this resin composition is 1 j 8 '
97wa” Compressive strength after ijn at room temperature 33yu/
(2) 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 ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (X_1 to X_8 are H, Br, Cl, 3 carbon atoms 1 to 8
is an alkyl group or OH, one of X_1 to X_4 and one of X_5 to X_8 is -OH group, Y_1 and Y_2 are H, Br, Cl or carbon number 1 to 8
The alkyl group z of is -O-, -S-, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, but R
(represents H, an alkyl group having 1 to 8 carbon atoms or a phenyl group) (D) 4,4'-diaminodiphenylsulfone or 3,
3'-Diaminodiphenylsulfone 2, The composition according to claim 1, wherein the (A) bifunctional epoxy resin is a bisphenol A type and/or bisphenol F type epoxy resin. 3. (B) The trifunctional 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. Compositions as described in Section 1. 4 The molar ratio of epoxy groups in (A)/(B) is 1/0.1
Composition according to claim 1, characterized in that it is 1/1.2 to 1/1.2, preferably 1/0.2 to 1/1.0. 5. The composition according to claim 1, wherein the amount of (C) used satisfies the following formula. Sum of moles of epoxy groups in (A) and (B)/number of moles of phenolic OB in (C) = 1/0.1 to 1/0.96,
2. The composition according to claim 1, wherein the amount of (D) used satisfies the following formula. (Sum of moles of epoxy groups in (A) and (B)) - ((C
) / NH of amine (D)
molar number = 1/0.8 to 1/1.57, part or all of (A), all of (B), and all of (C) are added in advance to 80% of the phenolic OH of (C). The above (A
2. The composition according to claim 1, wherein the composition is used after preliminary reaction with the epoxy group of (B). 8. The composition according to claim 7, wherein the molar ratio of the epoxy groups of (A)/(B) used in the preliminary reaction is 1/0.3 to 1/3.0. 9. The composition according to claim 7, wherein the amount of (C) used in the preliminary reaction satisfies the following formula. Sum of moles of epoxy groups in (A) and (B)/number of moles of phenolic OH in (C) = 1/0.2 to 1/1.110
2. The composition according to claim 1, further comprising reinforcing fibers.