US 9,309,354 B2 · Thermosetting composition and process for preparing fiber-reinforced composites

Abstract

A two-component curable epoxy resin system is disclosed. The resin system includes an epoxy resin component containing at least 80% by weight of a polyglycidyl ether of a polyphenol that has an epoxy equivalent weight of up to about 200 and contains no more than 2% by weight of monohydrolyzed resin species. The system also includes a hardener mixture that has an amino hydrogen equivalent weight of from 35 to 90 and contains at least 90% by weight of a mixture of (i) from 5 to 75% of the combined weight of (i), (ii) and (iii) of one or more compounds that have at least two primary and/or secondary aliphatic amino groups and which have no phenolic groups; (ii) from 10 to 95% of the combined weight of (i), (ii) and (iii) of one or more aminophenol compounds that contain one or more primary and/or secondary aliphatic amino groups and at least one phenolic group and (iii) from 0 to 50% of the combined weight of (i), (ii) and (iii) of one or more phenolic compounds that contain two or more phenolic groups and do not contain primary or secondary amino groups. The epoxy resin component and hardener mixture are present in amounts sufficient to provide from 1.05 to 1.35 equivalents of aliphatic amine hydrogens per equivalent of epoxide groups provided by the epoxy resin component. The system has beneficial curing characteristics that make it useful for producing fiber-reinforced composites in a resin transfer molding process.

Claims20

Dependent claims

A two-component curable epoxy resin system, comprising

I. an epoxy resin component containing at least 80% by weight of a polyglycidyl ether of a polyphenol that has an epoxy equivalent weight of up to about 250 and contains no more than 3% by weight of monohydrolyzed resin species;
II. a hardener mixture that has an amino hydrogen equivalent weight of from 25 to 90 and contains at least 90% by weight of a mixture of (i) from 5 to 75% of the combined weight of (i), (ii) and (iii) of one or more compounds that have at least two primary and/or secondary aliphatic or cycloaliphatic amino groups and which have no phenolic groups;
(ii) from 10 to 95% of the combined weight of (i), (ii) and (iii) of one or more aminophenol compounds that contain one or more primary and/or secondary aliphatic or cycloaliphatic amino groups and at least one phenolic group and (iii) from 0 to 50% of the combined weight of (i), (ii) and (iii) of one or more phenolic compounds that contain two or more phenolic groups and do not contain primary or secondary amino groups;
components I and II being present in amounts sufficient to provide from 1.05 to 1.35 equivalents of aliphatic or cycloaliphatic amine hydrogens per equivalent of epoxide groups provided by the epoxy resin component.

1 more element

A process for forming a fiber-reinforced epoxy composite, comprising;

a) pre-heating an epoxy resin component to a temperature of about 30 to 150° C.;
b) mixing the pre-heated epoxy resin component with a hardener by impingement mixing and transferring the resulting mixture into a mold that contains reinforcing fibers, and
c) curing the mixture in the mold to form the fiber-reinforced epoxy composite, wherein;
1) the epoxy resin component contains at least 80% by weight of a polyglycidyl ether of a polyphenol that has an epoxy equivalent weight of up to about 250, and the epoxy resin component contains no more than 3% by weight of monohydrolyzed resin species;
2) the hardener is at a temperature of no greater than 60° C. when mixed with the pre-heated epoxy resin component;
3) the mold is preheated to a temperature of at least 70° C. when the mixture of the epoxy resin and the hardener is transferred into the mold;
4) the hardener is a mixture that has an amino hydrogen equivalent weight of from 25 to 90 and which contains at least 90% by weight of (i) from 5 to 75% of the combined weight of (i), (ii) and (iii) of one or more compounds that have at least two primary and/or secondary aliphatic or cycloaliphatic amino groups and which have no phenolic groups;
(ii) from 10 to 95% of the combined weight (i), (ii) and (iii) of one or more aminophenol compounds that contain one or more primary and/or secondary aliphatic or cycloaliphatic amino groups and at least one phenolic group and (iii) from 0 to 50% of the combined weight of (i), (ii) and (iii) of one or more phenolic compounds that contain two or more phenolic groups and do not contain primary or secondary amino groups;
and
5) the ratio of the epoxy resin component and the hardener is such that from 1.05 to 1.35 equivalents of aliphatic or cycloaliphatic amine hydrogens are provided by the hardener per equivalent of epoxide groups provided by the epoxy resin component.

7 more elements

Dependencies are inferred from the claim text.

Thermosetting composition and process for preparing fiber-reinforced composites

Life of this patent

Thermosetting composition and process for preparing fiber-reinforced composites

Life of this patent

Abstract

Claims20