Polydispersity index of polymers revealed by DOSY NMR

► An NMR method for polydispersity determination of linear polymers is presented. ► It is based on differential diffusion observed for main chain and extremity signals. ► A statistical analysis of the DOSY spectrum provides an accurate estimates of PDI. ► The Flory coefficient of the polymer chain has to be known. ► Results on PEO reveal a very good accuracy.