Amorphous polymers do not possess melting points, but softening point
At low temperatures, polymers exist as glassy materials
In this state, the solid tends to shatter if it is hit, because the molecular chains cannot move at all easily.
If the polymer is heated, it eventually softens and becomes more flexible
This happens at the glass transition temperature (Tg)
After this, crystalline and amorphous thermoplastic polymers behaves differently
Heating has little effect on thermosetting polymers, until at a high temperature, they are destroyed.
Softening indicates that the polymer chains have gained enough energy to move slightly.
The softened polymer does not shatter, because the energy of the blow on the polymer gets dispersed by the chains moving violently and passing on the energy along and across chains
A polymer has the ability to flex & twist its chains, is called elastomer