PCL(2k)-PEG(5k)-N3 has terminal azide which can react with terminal alkyne in the presence of Cu catalyst or with DBCO/BCN via copper free click chemistry. The polymer forms micelles in water where the core contains polycaprolactone (PCL) and the shell is made of PEG. This polymer can be used to prepare nanocarrier for therapeutic agents/drugs. Reagent grade, for research purpose.