Disks, toroids and other multicompartment micelles from the assembly of charged triblocks or diblock copolymer blends

POLY 17

Darrin J. Pochan, pochan@udel.edu1, Honggang Cui2, Zhibin Li, zhibinli@udel.edu2, Kelly Hales2, Karen L. Wooley, klwooley@artsci.wustl.edu3, and Zhiyun Chen, zchenb@artsci.wustl.edu4. (1) Department of Materials Science and Engineering, University of Delaware, 201 DuPont Hall, Newark, DE 19716, (2) Department of Materials Science and Engineering and Delaware Biotechnology Institute, University of Delaware, 19716 Newark, DE, (3) Center for Materials Innovation and Department of Chemistry, Washington University in Saint Louis, Campus Box 1134, One Brookings Drive, Saint Louis, MO 63130-4899, (4) Center for Materials Innovation, Department of Chemistry, Washington University, One Brookings Dr, 63130 Saint Louis, MO
By manipulating the interaction of charged block copolymer hydrophilic corona blocks with multivalent organic counterions, novel and traditional micelle geometries such as disks and toroids vs. vesicles and cylinders can be controllably self-assembled. Specifically, polyacrylic acid-b-polymethacrylate-b-polystyrene amphiphilic triblock copolymers were studied in water/THF solvent mixtures with organic diamines as counterions. The system has been investigated by means of transmission electron microscopy (TEM), cryo-TEM, and small angle neutron scattering (SANS). By altering the water content of the solvent mixture, the hydrophobic polystyrene chain length, the chemical structure of the diamine counterions, and diamine counterion concentrations, one can predicatively access different structures with the same triblock copolymer and directly characterize the kinetic pathways between different structures. In addition, hierarchical stacking of micelle structures can be induced due to intermicellar interactions and micelles can be formed with internal phase separation with blends of different block copolymers.
 

Multicompartment Micelles: Higher Order Self-assembly of Block Copolymers
8:30 AM-12:00 PM, Sunday, 10 September 2006 San Francisco Marriott -- Salon B2, Oral

Division of Polymer Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006