Resin composition for fiber-reinforced plastic, and fiberreinforced plastic containing said composition

Patent metadata

Field	Value
Publication number	US-12435178-B2
Application number	US-202017429501-A
Country	US
Kind code	B2
Filing date	Mar 4, 2020
Priority date	Mar 8, 2019
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

A resin composition for fiber-reinforced plastic having a good balance between stability and curability and capable of producing fiber-reinforced plastic with improved strength. The composition contains an epoxy resin, an acid anhydride, and a catalyst that is liquid at 25° C. The catalyst is at least one member selected from the group consisting of a compound composed of an acid and a base and a compound composed of a quaternary onium cation and an anion.

First claim

The invention claimed is:

1. A composition comprising 100 parts by mass of reinforcing fibers and 5 to 150 parts by mass of a resin composition for fiber-reinforced plastic comprising (A) an epoxy resin, (B) an acid anhydride, and (C) a catalyst that is liquid at 25° C.,
the catalyst (C) comprising at least one member selected from the group consisting of (c1) a compound composed of an acid derived from an aromatic compound comprising phenol or nonylphenol and an organic base derived from a cyclic amidine comprising 1,8-diazabicyclo[5.4.0]undec-7-ene or 1,5-diazabicyclo[4.3.0]non-5-ene and (c2) a compound composed of a tetraalkylphosphonium cation and an anion selected from the group consisting of alkylphosphorodithioate, alkyl phosphate, and ethyl sulfate,
wherein the resin composition contains 5.1 to 20 parts by mass of the catalyst (C) per 100 parts by mass of the epoxy resin (A),
wherein the resin composition for fiber-reinforced plastic has a rate of viscosity increase of 200% or less, measured as follows:
a 2000 g portion of the resin composition is put in a container, and its temperature is adjusted to 25° C.; a first viscosity V1 of the resin composition at 25° C. is measured; then an acceleration test is performed on the resin composition, and a second viscosity V2 of the resin composition at 25° C. is measured after the acceleration test to calculate the rate of viscosity increase according to the equation:
rate of viscosity increase (%)=( V 2/ V 1)×100:

wherein the acceleration test is carried out by leaving the container containing the resin composition in a water bath kept at 25° C. for 4 hours,
wherein the acid anhydride (B) comprises an unsaturated alicyclic polycarboxylic acid anhydride which is liquid at 25° C., and the content of the acid anhydride (B) in the resin composition is such that the number of the acid anhydride groups in the acid anhydride is 0.9 to 1.2 per epoxy group in the epoxy resin, and
wherein the epoxy resin (A) comprises a dicyclopentadiene epoxy resin represented by formula (1):

where R 1 and R 2 each independently represent a hydrogen atom or a methyl group.

2. The composition according to claim 1 , wherein the epoxy resin (A) comprises a polyglycidyl ether of a bisphenol-alkylene oxide adduct.

3. The composition according to claim 2 , wherein the polyglycidyl ether of a bisphenol-alkylene oxide adduct is present in an amount of 10 to 80 mass % relative to the epoxy resin (A).

4. The composition according to claim 1 , wherein the dicyclopentadiene epoxy resin is present in an amount of 0.1 to 30 mass % relative to the epoxy resin (A).

5. The composition according to claim 1 , wherein the catalyst (C) comprises the compound (c1).

6. The composition according to claim 1 , wherein the anion is alkylphosphorodithioate.

7. The composition according to claim 1 , further comprising (D) a silane coupling agent.

8. A fiber-reinforced plastic obtained by curing the composition according to claim 1 .

9. A method for producing a fiber-reinforced plastic comprising providing the composition according to claim 1 , and curing the composition.

Assignees

• Adeka Corp

Inventors

• Morino Kazuhide
• Fujita Naohiro

Classifications

• C08J5/249

  characterised by the additives used in the prepolymer mixture · CPC title

• C08K5/5435

  containing oxygen in a ring · CPC title

• C08J2363/02

  Polyglycidyl ethers of bis-phenols · CPC title

• C08G59/688

  containing phosphorus · CPC title

• C08G59/683

  Phenolates · CPC title