Epoxy resins.

Epoxy resins

Epoxy resins are also known as polyepoxides.
They belong to the category of reactive prepolymers and polymers that contain the epoxide group. The epoxide group is also called oxirane group, is shown below.

Epoxide group.
Most common epoxy resins are produced from a reaction between epichlorohydrin (ECH) and bisphenol-A (BPA), though the latter may be replaced by other raw materials.
Diglycidyl ether of bisphenol-A (DGEBA) and novolac epoxy resins are most commonly used epoxies.
Diglycidyl ether of bisphenol-A (DGEBA) is a typical commercial epoxy resins and are synthesized by reacting bisphenol-A with epichlorohydrin in presence of a basic catalyst.

Diglycidyl ether of bisphenol-A.
There are two main categories of epoxy resins, namely the glycidyl epoxy resins and non glycidyl epoxy resins.
The glycidyl epoxies are further classified as glycidyl ether, glycidyl ester and glycidyl amine.
The non glycidyl epoxies are either aliphatic or cycloaliphatic epoxy resins.
Epoxy resins are available in the form of liquid as well as high viscosity solid.
The epoxy resins are thermosetting polymers and have excellent electrical properties, low shrinkage and resistance to moisture, thermal and mechanical shocks.
The epoxy resins are used as adhesives and as coatings. NEXT

Uses of epoxy resins.

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Polymers

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