PCL(1k)-PEG(3k)-N3 is an amphiphilic block copolymer which can self assemble in water to form micelles. It can be used to encapsulate hydrophobic drugs for targeted delivery. The azide moiety can react with terminal alkyne in the presence of Cu catalyst or with cyclooctyne, such as DBCO or BCN to form a stable triazole bond. Reagent grade, for research purpose.