Dual Redox and Thermoresponsive Double Hydrophilic Block Copolymers with Tunable Thermoresponsive Properties and Self-Assembly Behavior

摘要

The synthesis, tunable thermoresponsive properties, and self-assembly of dual redox and thermoresponsive double hydrophilic block copolymers having pendant disulfi de linkages (DHBCss) are reported. Well-defi ned DHBCss composed of a hydrophilic poly(ethylene oxide) block and a dual thermo- and reduction-responsive random copolymer block containing pendant disulfi de linkages are synthesized by atom transfer radical polymerization. Their lower critical solution temperature (LCST) transitions are adjusted through modulating pendant hydrophobic-hydrophilic balance with disulfi de-thiol-sulfi de chemistry. Further, these DHBCss derivatives are converted to disulfi de-crosslinked nanogels at temperatures above LCST through temperaturedriven self-assembly and in situ disulfi de crosslinking. They exhibit enhanced colloidal stability and further reductionresponsive degradability, thus demonstrating versatility of dual thermo- and reduction-responsive smart materials.