PCL(2k)-PEG(1k)-ALK is an azide reactive amphiphilic block copolymer in the presence of copper (Cu) catalyst. The polymer can self-assemble in aqueous media to form micelles with core regions made of hydrophobic polycaprolactone (PCL) and the shell contains hydophilic PEG. It can be used to prepare drug loaded nanoparticles for targeted delivery in nanomdicine. Reagent grade, for research purpose.