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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.
    Oxirane group
    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.
    DGEBA
    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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