Structure of Micelles Formed by Highly Asymmetric Polystyrene-b-Polydimethylsiloxane and Polystyrene-b-poly[5-(N,N-diethylamino)isoprene] Diblock Copolymers

FERNANDO C. GIACOMELLI; IZABEL C. RIEGEL; PETR STEPÁNEK; CESAR L. PETZHOLD; MARIO D. NINAGO; ANGEL J. SATTI; ANDRÉS E. CIOLINO; MARCELO A. VILLAR; VANESSA SCHMIDT; CRISTIANO GIACOMELLI

LANGMUIR

AMER CHEMICAL SOC

Año: 2010 vol. 26 p. 14494 - 14501

0743-7463

The internal structure of polystyrene(PS)-shell micelles having core-forming blocks consisting of polydimethylsiloxane(PDMS) or poly[5-(N,N-diethylamino)isoprene] (PAI) was determined in detail by accessing the multilevel structuralorganization using static and dynamic light scattering and small-angle X-ray scattering techniques. Well-defined PSb-PDMS and PS-b-PAI diblock copolymers with molar masses in the range of 12.0k-18.2k g/mol were dispersed incyclohexane, dimethylacetamide, or dimethylformamide. Colloidal nanoparticles exhibiting either swollen core with alarge surface area per corona chain that enables the PS chains to assume a random coil conformation with Gaussianstatistics, or compact core and slightly stretched PS chains in the corona were obtained. Therefore, the results of thisstudy provide an interesting alternative allowing for precise control of the core and corona properties of PS-b-PDMSand PS-b-PAI micelles in selective solvents. Admittedly, such differences in terms of micellar properties can dictate thepotential of block copolymer micelles for generating thin films from preformed nano-objects, as well as the capability tofunction as nanoreactors in organic medium.