Reversible micellisation of a thermo- and pH- responsive hydrophilic block copolymer in water

摘要

Block copolymer micelles that can dissociate into the molecularly dissolved unimers in response to external stimuli are of great interest for controlled encapsulation and triggered release of substances in many technological applications. A common principle for destabilising micelles or vesicles involves the modification of the polarity or hydrophobic/hydrophilic balance (HLB) of the core-forming component by the use of an external trigger. When the core-forming component becomes soluble in the medium, the driving force for the micellisation is eliminated and the micelles disassemble. The dissociation can be reversible or irreversible depending on the response mechanism. Among various chemical and physical stimuli that have been employed to induce the formation and dissociation of block copolymer micelles, temperature, pH, and light are the most common used.