Question

Distinguish between thermoplastic and thermosetting polymer.

What is the difference between thermosetting and thermoplastic polymers? Give an example of each.

Answer 1

Thermoplastic Polymer	Thermosetting Polymer
These are formed by addition polymerisation.	These are formed by condensation polymerisation.
They have low molecular weight.	They have high molecular weight.
They are usually soft, weak, and less brittle.	They are usually hard, strong, and more brittle.
They are long-chain linear polymers with negligible cross-links	They have a three-dimensional network structure with a number of crosslinks.
They are usually soluble in some organic solvents.	Due to strong bonds and crosslinks, they are insoluble in almost all organic solvents.
They get softened on reheating readily because secondary forces between the individual chains can break easily by heat or pressure.	They do not soften on reheating because the crosslinks and bonds retain their strength on heating.
Examples: Polyethylene, Polystyrene, PVC, PVA. Nylon 6,6	Example: Phenolformaldehyde, ureaformaldehyde.