NEET Chemistry Notes Polymers – Polyesters
Polyesters
polyesters
The polymers which contain an ester linkage are known as polyesters
eg:Dacron
- polymethylmethacrylate(PMMA)
It is prepared by the polymerisation of methylmethacrylate in the presence of suitable organic peroxide
The polymer is known by several commercial names such as lucite, acrylite, plexiglass and perspex.
Properties and uses
It is a hard and transparent polymer and is quite resistant to the effect of light, heat and ageing. It is used, in the manufacture of unbreakable lights, protective coatings, dentures, and in making windows for aircrafts.
- Glyptal
It is a polyester having crosslinks. It is a thermosetting plastic. It is obtained by condensation of ethylene glycol and phthalic acid or glycerol.
When its solution in a suitable solvent is evaporated, it leaves a tough but non-flexible film. It is, therefore, used in the manufacture of paints and lacquers.
- Terylene (Dacron)
It is a condensation product of ethylene glycol and terephthalic acid. Polymerisation is carried out at 420 to 460 K in the presence of
Properties and Uses
Terylene is highly resistant to the action of chemical and biological agents. Its fibres are quite strong and durable. It can also be blended with wool or cotton to obtain fabrics of desired composition.
Terylene is used in the manufacture of a variety of clothes such as terycot, terywool and terysilk as a result of blending with other yerns. It is also used for preparing magnetic recording tapes, conveyer belts, aprons for industrial workers etc.
- Biodegradable Polymers
