Question

why thermoplastic become soft and melt on heating​

Answer 1

Answer:

hope i think itwill help you mate

Answer 2

Answer:

Thermoplastic become soft on heating because they are made up of loose sliding chains of polymers

Explanation:

You know what happens to a molecule / particle when heated, isn't it? It gets energized and moves in Brownian motion (Random motion)

So when thermoplastic are heated, because of their sliding chains of polymers, the chains become energized and moves randomly due to which thermoplastic become soft and can be remolded into other items