Synthesis and self-assembly of asymmetric block copolymer of dendritic polyether and poly (N-isopropylacrylamide)

An asymmetric block copolymer of polyether dendrimer and poly(N-isopropylacrylamide) (Dendr. PE-PNIPAM) was prepared by atom transfer radical polymerization methods. The experimental results showed that these asymmetric copolymers easily self-assembled into bilayer supramolecular aggregates by hydrophobic association in aqueous solution. The critical aggregation concentrations (CAC) and morphologies of aggregates derived from these dendritic amphiphiles in aqueous solution were highly dependent on the generation of dendrimer. These copolymers exhibited a marked response to temperature stimulation and phase transition occurred at body temperature (37.5 degreesC). At temperatures above the phase transition temperature, the multiple super-aggregates such as the ribbon tubule shapes aggregates were formed.