An object of the present invention is to provide an epoxy resin composition excellent in elastic modulus and strength, and a prepreg and a fiber reinforced composite material with the epoxy resin composition. The present invention is the epoxy resin composition including the following components [A] to [C] and satisfying the following conditions (1) to (3): [A]: epoxy resin [B]: aromatic diamine [C]: a compound having a boiling point of 130° C. or more and a molecular weight m of 50 or more and 250 or less, the compound having no epoxy group in the molecule and having substantially no curing ability of an epoxy resin

(1): at least a part of the component [C] satisfies that the sum of the polar component and the hydrogen bond component in the Hansen solubility parameters is 10.0 or more.

(2): at least a part of the component [C] satisfies that the Hansen solubility parameter distance L to the component [A] is 20.0 or less.

(3): the ratio H/E between the amount by mole, E, of the epoxy group of the component [A] and the amount by mole, C, of the component [C] satisfying both the condition (1) and the condition (2) is 0.01 or more and 0.20 or less.

(4): the viscosity at 70° C. for 2 hours is 5.0 times or less the initial viscosity at 70° C.

An object of the present invention is to provide an epoxy resin composition that can be preferably used for prepreg and fiber reinforced composite material applications and is excellent in elastic modulus, strength, and pot life.

The present invention is the epoxy resin composition including the following components [A] to [C] and satisfying the following conditions (1) to (3): [A]: epoxy resin [B]: polyamine curing agent, and [C]: a compound having a boiling point of 130° C. or more and a molecular weight m of 50 or more and 250 or less, the compound having no epoxy group in the molecule and having substantially no curing ability of an epoxy resin, and (1): at least a part of the component [C] has two or more alcoholic hydroxyl groups in the molecule. (2): the ratio C/E of the amount by mole, E, for epoxy groups of the component [A] to the amount by mole, C, of the component [C] satisfying the condition (1) is 0.01 or more and 0.20 or less. (3): the viscosity at 70° C. for 2 hours is 5.0 times or less the initial viscosity at 70° C.

An epoxy resin mixture which contains an epoxy resin represented by Formula (1) below and an epoxy resin represented by Formula (2) below at a weight ratio of 1:5 to 1:0.2. (In Formula (1), plural R1's each exist independently and represent a hydrogen atom or a C1-10 alkyl group, n represent a real number of 1 to 10, and G represents a substituted or unsubstituted glycidyl group.) (In Formula (2), plural R2's and R3's each exist independently and represent a hydrogen atom or a C1-10 alkyl group, n represents a real number of 1 to 10, and G represents a substituted or unsubstituted glycidyl group.)

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An epoxy resin mixture which contains an epoxy resin represented by Formula (1) below and an epoxy resin represented by Formula (2) below at a weight ratio of 1:5 to 1:0.2. (In Formula (1), plural R1's each exist independently and represent a hydrogen atom or a C1-10 alkyl group, n represent a real number of 1 to 10, and G represents a substituted or unsubstituted glycidyl group.) (In Formula (2), plural R2's and R3's each exist independently and represent a hydrogen atom or a C1-10 alkyl group, n represents a real number of 1 to 10, and G represents a substituted or unsubstituted glycidyl group.)

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The invention relates to a hydrogel based on water, on hydrosoluble monomeric or polymeric isosorbide epoxide and on hydrosoluble amine, to the method for preparing same and to the use thereof.

Provided are a curable composition which is rapidly curable and which gives cured products with good heat resistance, a cured product thereof, a fiber-reinforced composite material, a fiber-reinforced resin-molded article, and a method for manufacturing the fiber-reinforced resin-molded article. Provided are a curable composition containing an epoxy resin (A), an aliphatic and/or alicyclic amine compound (B), and an imidazole compound (C), wherein the ratio H/E of the number of moles H of active hydrogen in the aliphatic and/or alicyclic amine compound (B) to the number of moles E of an epoxy group in the epoxy resin (A) is in the range of 0.2 to 0.9; a cured product thereof; a fiber-reinforced composite material; a fiber-reinforced resin-molded article; and a method for manufacturing the fiber-reinforced resin-molded article.

An epoxy resin composition including components (A), (B), (C) and (D); wherein a content of the component (A) is 60 to 90 parts by mass, and a content of the component (B) is 10 to 40 parts by mass, with respect to epoxy resins; the epoxy resin composition has a characteristic that, when cured and formed into a cured product, the cured product has a glass transition temperature of 200° C. or higher; and a viscosity at 100° C. of the resin composition is 5 to 35 Pa.Math.s, wherein Component (A) is an aromatic epoxy resin having at least 3 glycidyl groups in one molecule, Component (B) is an aromatic epoxy resin having two glycidyl groups in one molecule, Component (C) is an aromatic polysulfone resin having a reduced viscosity of 0.18 to 0.30 dl/g; and Component (D) is an aromatic amine compound.

A multiple component anhydride-free, thermosetting epoxy resin composition comprising, (A) at least one epoxy resin, and (B) at least one curing agent selected from the group of (b1) a polyetheramine of the formula (1) (Formula (1)), wherein x is a number of from 2 to 8, and (b2) a polyetheramine with at least one terminal end group of the formula (2) (Formula (2)), and (C) at least one epoxy silane, is, in particular, suitable for the manufacture of instrument transformers and dry-type transformers by casting, potting and encapsulation processes, wherein said articles exhibit good mechanical, electrical and dielectrical properties. ##STR00001##

An intumescent composition capable of withstanding temperature cycling as low as −60° C. without cracking is contemplated. The composition also exhibits enhanced durability due to its resistance to water absorption, its acceptable cure times, and (when exposed to fire conditions) its well-adhered, foamed char layer.

The present disclosure provides a curing agent comprising a polyetheramine, a tertiary amine and an alkanolamine. The curing agent may be combined with an epoxy resin to form a curable composition which is capable of being applied to a substrate and cured to form a cured article.