# Impact strength polymers

1. Oct 5, 2012

### rexol

This is not a specific question. it's just common sense. all temp values in celsius.

The impact values of polymers are definitely astonishing when i think at the molecular level

it is said that increasing the molecular weight of the chains increase the impact strength.
consider same polydispersity index (Mw / Mn).

now consider a cross section where u are applying the impact.

won't there be less number of chain ends to absorb the impact? so, impact strength should decrease right?

also, how does Polycarbonate have such a high impact strength at 0. it's glass transition is 140 !!!!