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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