As per RIVetron above UHMWPE is excellent for both mechanical and chemical abrasiveness. UHMW might be a better alternative to PTFE (teflon) in terms of cost but I believe it has a higher density.
As a correction to my above comment Izod testing has different notch styles to be concerned with not so much specimen thickness. Thickness is more a concern when reviewing heat related deflection tests...OOPS!
I work in Automtive lighting but in general one of the most impact resistant materials we use is polycarbonate (for headlamps). Another material is ABS which is pretty impact insensitive but a much weaker material that PC. I would begin looking at Izod test imformation for ABS since it is very...