Macromolecules, Vol.28, No.8, 2874-2881, 1995
Characterization of Unimolecular Micelles of Random Copolymers of Sodium 2-(Acrylamido)-2-Methylpropanesulfonate and Methacrylamides Bearing Bulky Hydrophobic Substituents
The self-organization of random copolymers of sodium 2-(acrylamido)-2-methylpropane-sulfonate and methacrylamides bearing bulky hydrophobic groups, such as lauryl (LA), cyclododecyl (CD), and 1-adamantyl (AD) groups, was investigated by fluorescence, NMR relaxation, FTIR, light scattering, and small-angle X-ray scattering techniques. In aqueous solution, the hydrophobes in these polymers form clusters as a result of either intramolecular or intermolecular self-association. Studies of nonradiative energy transfer between polymers labeled with naphthalene and pyrene revealed that the polymers having the CD and AD groups formed unimolecular micelles (unimers) in a wide range of concentrations up to several weight percent, whereas the polymer having the LA groups could exist as a unimer only in a much lower concentration range (
Keywords:AMPHIPHILIC POLYELECTROLYTE SYSTEMS;PHOTOINDUCED ELECTRON-TRANSFER;NONRADIATIVE ENERGY-TRANSFER;PHOTON-HARVESTING POLYMERS;AQUEOUS-SOLUTION;MALEIC-ACID;MODIFIED POLY(N-ISOPROPYLACRYLAMIDES);POLY(METHACRYLIC ACID);ALTERNATING COPOLYMERS;MICROPHASE STRUCTURE