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Thermosetting resins.

Thermosetting resins

  • Thermosetting resins are the materials that undergoes irreversible changes under the influence of heat from a fusible and soluble materials into infusible and insoluble materials through the formation of covalently cross-linked, thermally stable networks.
  • The main characteristic of thermosets is that they require curing.
  • Thermosets are generally used in liquid state and solidify and harden on curing.
  • Some resins can be part cure and hold on to what is called B stage for completely curing at latter time.
  • Some examples of thermosets include epoxies, polyesters and formaldehyde based resins.
  • The formaldehyde based resins is classified into two classes, the condensation products obtained on reacting formaldehyde with phenol (or resorcinol) called phenolic resins or phenoplasts and the products obtained on reacting formaldehyde with urea (or melamine) called amino resins or amino plastics.
  • Thermosetting resins have excellent resistance to solvents and corrosives.
  • They have high resistance to heat and high temperature.
  • They have excellent adhesion.
  • Thermosetting resins are resins that do not soften on heating. They are used when resistance to heat is important (eg kettles, plugs, laptop chargers etc). 
    Uses of Thermosetting resins
    Uses of thermosets.
  • Thermosets may also be used as an adhesives.
  • Shoe soles, foams and car tires are also made of thermosets. NEXT
    Uses of Thermosetting resins.

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