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Polyester resins.

Polyester resins

  • Polyester resins are unsaturated synthetic resins.
  • These unsaturated polyester resins are condensation polymer formed on reacting polyols i.e the compound containing multiple 'hydroxy' functional group, with a saturated or unsaturated dibasic acid.
  • Typically, the Polyols used are glycols for example ethylene glycol and the dibasic acid used are phthalic acid, isophthalic acid and maleic acid.
  • The biproduct water formed during esterification is continuously removed and driving the reaction to completion.
  • An example of polyester resin is polyethylene terepthalate (PET).
  • Polyester resins have adequate resistance to water and other chemicals, low shrinkage, styrene odour and are difficult to mix than other resins.
  • Polyester resins have adequate resistance to weathering and ageing.
  • Polyester resins can withstand a temperature upto 80°C.
  • The wall panel fabricated from polyester reinforce with fibreglass called fibreglass reinforced plastic (FRP) are used in many restaurants, kitchens and other areas with washable low maintenance wall.
  • In USA they are used as overlays on roads and bridges. In this application they are known as PCO (Polyester Concrete Overlays). Next
    Uses of polyester resins.

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