Surfactant properties of poly(dimethylsiloxane)-containing block copolymers from living radical polymerization

Transition metal mediated living radical polymerization has been utilized to prepare amphiphilic PDMS containing block copolymers. The PDMS based macroinitiator has been synthesized for allow the polymerization of 2-dimethylaminoethyl methacrylate (DMAEMA) monomers with Cu(I)Br/npropyl-2-pyridinalmethanimine complex. Well-defined block copolymers have been prepared with different molecular weights of DMAEMA block. Dynamic surface tension of aqueous solutions of poly(DMAEMA-DMSDMAEMA) were investigated at different pH. These block copolymers were found to be highly surface active in aqueous media, particularly in basic pH where the charge density (degree of protonation) of the DMAEMA is low. An improvement in aggregation formation is established by the addition of salt (NaCl) in the aqueous solution. Aggregates formed with these polymers have a large hydrodynamic diameter.