Synthesis, Morphologies, and Photophysical Properties of Poly2,7-(9,9- dihexylfluorene)-block-poly(N- isopropylacrylamide)-block-poly(N- hydroxyethylacrylamide) Rod-Coil-Coil Thermoresponsive Triblock Copolymers

摘要

Poly(N-isopropylacrylamide) (PNIPAAm) is one of the most widely studied thermoresponsive water-soluble polymers, which exhibits a lower critical solution temperature (LCST). PNIPAAm diblock copolymers with the reversible structural changes of core-shell micelles could be obtained simply by varying environmental conditions. Apart from core-shell micelles, the core-shell-corona micelles were observed from the self-assembled of PNIPAAm based triblock copolymers above LCST. Recently, Grubbs et al. reported the solution behavior of a triblock copolymer poly(ethylene oxide)-b-PNIPAAm-b-polyisoprene (PEO-b-PNIPAAm-b-PI), which showed large vesicles with a bilayer structure above the LCST. The temperature-induced assembled structures of PEO-b-PNIPAAm-b-PI were controlled by the hydrophilic/hydrophobic balance. However, the synthesis, morphology, and properties of fluorescent PNIPAAm based triblock copolymers have not been fully explored.