JPH0143770B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an epoxy resin composition which, when cured, yields a cured product having high strength and high modulus of elasticity, and which is used for relatively large impregnated and cast products and composite materials such as buoyancy materials. Conventionally, when producing cast or impregnated molded products using epoxy resin, a combination of liquid epoxy resin and a curing agent has been used. As the curing agent, a resin having a small epoxy equivalent such as a polyfunctional epoxy resin is used, or as a curing agent, a polyfunctional acid anhydride or a compound containing a hydroxyl group is used. As examples of the use of polyfunctional hydroxyl group-containing compounds as epoxy resin curing agents, phenol resin, poly-p-vinylphenol (Maruzen Sekiyu, Resin M), bisphenol A, etc. are known.
When these are blended into epoxy resins, the resulting mixture has a high viscosity, resulting in poor workability during impregnation, casting, etc., and the resulting products also have high strength and high elastic modulus. It's not a thing.
Furthermore, resorcinol is sometimes used as an amine curing accelerator for bisphenol A and F type epoxy resins (Adhesive Age, April,
1967, pp. 20-27), the products obtained in this case are also not of high strength and high modulus. The present invention has been made in view of these circumstances, and provides an epoxy resin composition that has good workability and is suitable for impregnation, casting, etc., and can yield products with high strength and high elastic modulus. The purpose is to Therefore, the epoxy resin composition of the present invention consists of an alicyclic epoxy resin, dihydroxybenzenes, and an acid anhydride, and R=B+C/A f=C/B+C×100 (in the above formula, A: epoxy resin Amount expressed in parts by weight/Epoxy equivalent, B: Amount expressed in parts by weight of acid anhydride/Acid anhydride equivalent, C: Amount expressed in parts by weight of dihydroxybenzenes/Equivalent of hydroxyl group of dihydroxybenzene ), then 0.7
It is characterized in that ≦R≦1.5 and 50≦f≦100. The epoxy equivalent, acid anhydride equivalent, and hydroxyl equivalent in the present invention are as follows. Epoxy equivalent: molecular weight per epoxy group. For example, in the case of 3,4-epoxycyclohexylmethyl-(3,4-epoxy)cyclohexanecarboxylate (molecular weight 252) shown in (1) below, the epoxy equivalent is 126. Acid anhydride equivalent: molecular weight per acid anhydride group. For example, it is 178 for methylnadic anhydride. Hydroxyl group equivalent: Molecular weight per hydroxyl group. for example,
In the case of hydroquinone, it is 55. Hereinafter, the configuration of the present invention will be explained in detail. The alicyclic epoxy resin used in the present invention is
It is an epoxy resin having an internal epoxide, and is liquid at room temperature, although it is not particularly limited, and is composed of, for example, the following. (1) CY−179 (CIBA) ERL−4221 (UCC) 3,4-Epoxycyclohexylmethyl-
(3,4-epoxy)cyclohexanecarboxylate (2) ERL-4229 (UCC) Bis(3,4-epoxycyclohexylmethyl)adipate (3) CY-175 (CIBA) ERL-4234 (UCC) Dicycloaliphatic diether diepoxide (4) ERL-4206 (UCC) Vinyl cyclohexene dioxide Furthermore, the dihydroxybenzenes used in the present invention have the following formula: (wherein R ₁ and R ₂ are the same or different groups and represent H, an alkyl group having 1 to 3 carbon atoms, Cl), such as the following dihydroxybenzenes and derivatives thereof. be. (1) Dihydroxybenzene: (2) Derivatives: Methyl, ethyl, propyl, and chloro compounds of the above dihydroxybenzene. Further, the acid anhydride used in the present invention is not particularly limited, but may be one that is liquid at room temperature in consideration of convenience in handling. Examples of the liquid acid anhydride include the following. (1) Methyl nadic anhydride (Methyl haimic anhydride (Hitachi Chemical)) (2) Methylhexahydrophthalic anhydride Rikaside MH-700 (New Japan Chemical) Epicron B-650 (Dainippon Ink) HN-5500 (Hitachi Chemical) (3) Methyltetrahydrophthalic anhydride HN-2200 (Hitachi Chemical) Epicron B-570 (Dainippon Ink) (4) In addition, there are liquid products that are made by blending and melting solid acid anhydrides. The epoxy resin composition of the present invention is composed of the above-mentioned alicyclic epoxy resin, dihydroxybenzenes, and acid anhydride, and when R=B+C/A f=C/B+C×100, 0.7≦R≦ 1.5 (preferably 0.9<R<
1.2) and has a value of 50≦f≦100. A is the amount expressed in parts by weight of epoxy resin/epoxy equivalent, B is the amount expressed in parts by weight of acid anhydride/acid anhydride equivalent, and C is the amount expressed in parts by weight of dihydroxybenzenes/dihydroxy. Each represents the hydroxyl equivalent of benzene. In the above formula, if R is smaller than 0.7, many unreacted epoxy groups remain and this acts as a plasticizer, resulting in low strength and elastic modulus.On the other hand, if R is larger than 1.5, unreacted epoxy groups remain. The agent remains, resulting in a brittle cured product with high elastic modulus but extremely low strength, making it difficult to obtain a final product with good physical properties. Also, regarding f, f=
100 (that is, when B = 0, in other words, when no acid anhydride is used), good physical properties can be obtained, but in general, dihydroxybenzenes are solid at room temperature, so this is not possible. When dissolved in epoxy resin, the viscosity becomes high and workability becomes poor. Therefore, in the present invention, it is preferable to use an acid anhydride together in order to improve this workability. Note that if f is smaller than 50, the effects of using dihydroxybenzene (ie, high strength and high elastic modulus) cannot be expected much. Therefore, in the present invention, 50≦f≦100. In addition,
The reason why f=100 was included is that the highest strength and elastic modulus can be obtained. The epoxy resin composition of the present invention is prepared as described above, but this composition may contain an accelerator such as a tertiary amine, if necessary.
In addition, this promoter is, for example, the following. (1) Tertiary amine (a) Triethanolamine N(CH ₂ -CH ₂ -OH) ₃ (b) Benzyldimethylamine (c) 2,4,6-tris(dimethylaminomethyl)phenol (DMP-30) (2) Imidazole Ethylmethylimidazole The present invention will be explained in more detail with reference to Examples below. Example 1 ERL-4221 as a cycloaliphatic epoxy resin
(UCC) 11 to 16 per 100 parts by weight (A = 0.79)
(C=0.2-1.2) parts by weight of resorcin were dissolved by heating, cooled, and 0-107 (B=0-0.6) parts by weight of methyl hymic acid anhydride (Hitachi Chemical) were added. R
= 0.5 to 1.5, and f = 50 to 100. To this, 0.5phr of triethanolamine was added as an accelerator to create a formulation, which was heated at 120℃ for 16 hours + 180 hours.
℃ for 16 hours, and the cured product was ASTM-
Compressive strength and elastic modulus were measured in accordance with D-695.
The results are shown in Table 1 below and in Figures 1, 2, 3, and 4 with black circles. Example 2 In place of resorcinol as dihydroxybenzene in Example 1, hydroquinone, chlorresorcinol, and dichlorresorcinol were used at 36, 47.1, and 47.1, respectively.
58.6 (C is 0.65 each) parts by weight used (R = 1.1, f =
75), the results of testing in the same manner as in Example 1 are shown in Table 1 below.

【table】

[Table] Comparative Example 1 Using 100 parts by weight (A = 0.79) of alicyclic epoxy resin ERL-4221 (UCC), 127 parts by weight (B = 0.71) of methyl hymic anhydride (Hitachi Chemical), and using resorcinol. A cured product was obtained in the same manner as in Example 1 (R = 0.9, f = 0 (no resorcinol). Also, 100 parts by weight of ERL-4221 (UCC) (A =
A cured product was obtained in the same manner as in Example 1 from 0.79), 44 to 126 parts by weight of methyl hymic anhydride (B = 0.53 to 0.71), and 10 to 13.2 parts by weight of resorcinol (C = 0.18 to 0.24) (R = 0.9-1.2, f=25). The compressive elastic modulus and compressive strength of these cured products were measured in the same manner as in the examples. R=0.9, f=0 and R=0.9
~1.2 and f=25 measurement results are shown in Figures 1 and 2.
It is indicated by an x mark in the figures, FIGS. 3 and 4. Also, R
The measurement results for f = 1.7, f = 50, and 100 are shown in Figs. 1 and 3 with △ marks. Comparative Example 2 As an example of liquid high-strength resin, 100 parts by weight (A = 0.57) of Epikote-152 (Cien Kagaku, novolak type epoxy resin) and 87 parts by weight of methyl nadixic anhydride (methyl highmic acid anhydride, Hitachi Chemical) were used. (B=0.49), triethanolamine 0.5 parts by weight (R=0.49/0.57=0.86, f=0/0.49=0) has a compressive strength of 1500 Kg/cm ² and an elastic modulus of 43100 Kg/cm ² . However, because the reaction is fast and the heat generated is large, it is not possible to mold large items.

[Brief explanation of drawings]

Figure 1 is a diagram showing the relationship between compressive elastic modulus and R, Figure 2 is a diagram showing the relationship between compressive elastic modulus and f, Figure 3 is a diagram showing the relationship between compressive strength and R, and Figure 4 is a diagram showing the relationship between compressive elastic modulus and R. is a diagram showing the relationship between compressive strength and f.

Claims (1)

[Scope of Claims] 1 Consists of an alicyclic epoxy resin, dihydroxybenzenes, and acid anhydride, R=B+C/A f=C/B+C×100 (in the above formula, A: expressed in parts by weight of the epoxy resin) B: Blend amount expressed in parts by weight of acid anhydride/Acid anhydride equivalent, C: Blend amount expressed in parts by weight of dihydroxybenzenes/Hydroxyl group equivalent of dihydroxybenzene), 0.7
An epoxy resin composition characterized in that ≦R≦1.5 and 50≦f≦100.