Question

How are polymers classified based on the physical properties?

Answer 1

On the basis of physical properties
They can be:
1) straight chain
2)branched
3)cross linked

Answer 2

i) Elastomers: The polymers that have elastic character like rubber are called elastomers.

In elastomers, the polymer chains are held together by weak inter-molecular forces.
Cause of these weak forces, the polymers can be easily stretched by applying small stress and regain their original shape when the stress is removed.
Ex:- Vulcanised rubber

ii) Thermoplastics: The polymers in which inter-molecules forces are between the elastomer polymers and fiber polymers.

These polymers are softened when it heated and hardened when it cooled.
These polymers do not have any cross bond.
These polymers can eaily convert into any shape by heating.
Ex:- Polyetene, Polystyrene, PVC etc.

iii) Thermosetting: Theses polymers are made by low molecular mass semi fluid substance.These polymers can not convert in other shape by heating.
On heating, they become hard and in-fusible because these polymers have cross bond.
Ex:- Bakelit, Melamine formaldehyde, Resin etc.

(iv) Fibers: These polymers have strong inter-molecules forces between the chains.