Structural control in functional rod-coil block copolymers

PMSE 30

Yuefei Tao, yftao@uclink.berkeley.edu1, Bradley D. Olsen, bdolsen@berkeley.edu2, Rachel A. Segalman, segalman@berkeley.edu2, and H. Zohar3. (1) Department of Chemistry, University of California Berkeley and Lawrence Berkeley National Laboratories, Berkeley, CA 94720-1462, (2) Department of Chemical Engineering, University of California Berkeley and Lawrence Berkeley National Laboratories, 402 Hildebrand Hall, Berkeley, CA 94720, (3) Department of Chemical Engineering, University of California Berkeley, 402 Hildebrand Hall, Berkeley, CA 94720
Nanopatterning of functional polymers on the 10 nm length scale is critical to the control of their properties. Although block copolymer self-assembly is an elegant route to achieve this control, the rodlike molecular shape of many functional polymers introduces liquid crystalline interactions not present in traditional block copolymers. We demonstrate that control of rod-coil block copolymer morphology requires tuning the molecular structure in three experimental dimensions to access the wide range of phases achievable with these molecules. Magnetic fields are also used to align lamellae-forming rod-coil block copolymers. The rod blocks align parallel to the magnetic field due to their diamagnetic moment, and the lamellar nanodomains are templated to self-assemble perpendicular to the field due to the rod alignment. The best order is achieved when the sample is first heated into the isotropic phase and then cooled into the lamellar phase, resulting in orientational order parameters greater than 0.9.
 

Synthesis and Self-Assembly Approaches to Polymer-Inorganic Hybrid Nanoparticles
1:30 PM-4:50 PM, Sunday, April 6, 2008 Hilton New Orleans Riverside -- Grand Salon 24, Oral

Division of Polymeric Materials: Science & Engineering

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008