Thermoset Composites

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Composites 101: Epoxy Resins

Our composites are made with epoxy resin, which is a thermosetting polymer or plastic that becomes permanently hard after "curing."

Epoxy or polyepoxide resin polymerizes and crosslinks when mixed with a catalyzing agent or “hardener.” In general, epoxies are known for their excellent adhesion, chemical and heat resistance, and good to excellent mechanical properties.

When epoxy is mixed with the appropriate catalyst, the resulting reaction is exothermic – meaning that it generates heat – and the oxygen molecule on the epoxy monomers is “flipped.” This occurs throughout the epoxy and a matrix with a high stress tolerance is formed and “glues” the materials together.

Epoxies are classified as “structural adhesives” or “engineering adhesives.” These high performance adhesives are used in the construction of aircraft, automobiles, bicycles, golf clubs, skis, snowboards, and other applications where high strength bonds are required.

Epoxies are exceptional adhesives for wood, metal, glass, stone, and some plastics. They can be made flexible or rigid, transparent or opaque/colored, fast setting or extremely slow. Epoxy adhesives are almost unmatched in heat and chemical resistance among common adhesives.

There are more than 100 commodity epoxy manufacturers in the world and countless “formulators” who blend or customize epoxies for specialty applications. The resin used in our composites comes from the second category, the custom epoxies designed to achieve specific performance requirements.


GCI and PolyOne