Thermosoftening / Setting (T5)

Question 1

Describe thermosetting..

Answer 1

Cross-links exist between the different long chains.

This prevents the cross-links from moving together meaning they tend to be harder materials and do not melt when heated.

They are heated only once, formed into their shape and that shape is retained.

Question 2

Describe thermosoftening..

Answer 2

Process of heating up the plastic until it melts and pouring it into a mould to set.

Within thermosoftening plastics the molecules are lined up but not interconnected, apart from weak forces that form tiny crystals between the molecules.

When the substance is heated the crystals begin to melt.

When the substance cools down the crystals reform and the material will harden again.