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 !!!!