Elasotomers - Iain

Question 1

Elastomeric Behaviour on microscopic level

Answer 1

liquids of polymer molecules - retain shape fo liquid being able to change shape easily
macroscopic solid like due to cross linking
polymer molecules unwind from jumbled to straight configuration, not changing chemical bonds
elasticity is controlled by entropy

Question 2

elastomers derivation

Answer 2

elastomeric material - the melt phase or solution phase
made from polymer melt - rubber
made from polymer solution - elastomeric gel

Question 3

what is the difference between chemical and physical crosslinks?

Answer 3

chemical - covalent bonds, tend to be very stable, strong stable artificial gels making thermosetting
physical - non covalent bonding mechanism, a lot weaker making thermoplastic

Question 4

what are the dynamic of random coil structure?

Answer 4

polymer coil is long and flexible - consistently moving
will move from time to time

Question 5

what are the assumptions of the random walk model?

Answer 5

1 - successive steps are uncorrelated
2 - monomers have negligible volume, chain cannot step twice in the same area
3 - monomers do not attract or repel each other