Question

Q2 block copolymer AB is formed by copolymerizing Polymer A, an isotactic polymer and polymer B, an atactic polymer. If copolymer AB molten solution is cooled down slowly to solidify the solution, is copolymer AB solid more likely to be amorphous, semi-crystalline or completely crystalline? if the molten solution is flash frozen in liquid nitrogen, which state will the copolymer more likely be in? Please draw the representative DSC curve showing all the possible features for copolymer AB solidified under each of these two scenarios. Describe the difference between these two DSC curves and explain why.

Answer 1

Solution : -

isotactic Polymer A

Atactic Polymer B

Isotactic polymer means highly arranged Polymer in which all the Groups arranged Polymer in which all the groups arranged in which a particular mamer with same repeating unit.

As crystallisation occur at slow Rate.

In first case in which soliclification occurs at slow rate these occurs crystallisation.

But due to in hezent irregularity of Atactic polymer B then it is semi crystallisation.

So crystallisation =

The DSC curve is a differential scanning calorimetery. It me asmes triangle H with the temp. As if semicrystallisation