PCL(5k)-PEG(6k)-PCL(5k) is an amphipathic triblock copolymer containing two hydrophobic polycaprolactone (PCL) blocks and hydrophilic PEG block. The polymer is biodegradable via hydrolytic attack on the ester bonds. Upon dispersion in water, the polymer self-assembles and can be used to prepare nanoparticles/nanomicellars for targeted drug delivery. Reagent grade, for research purpose.