PHYS 151 |
| Nanoporous silica thin films with pore size from below 5 nm to greater than 100 nm were fabricated using preformed block copolymer/homopolymer blend films as templates for silica condensation. Pore size control on multiple length scales is enabled through copolymer self-assembly and compositional dependent phase separation of the blend. Vitrification of the blend during film formation leads to arrested structures that can be templated through selective condensation of silica from vaporized precursors. This nanocomposite is further reduced to porous silica by removal of the polymeric phase via calcination. Partitioning of the catalyst (acid) between polymer phases provides additional handle for control of the pore morphology. Pore size is strongly dependent upon the interactions between components and the kinetics of film formation. These blend templates provide a simple route to multiple length scale porous materials. |
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Nanostructured Materials
1:20 PM-5:00 PM, Monday, April 7, 2008 Morial Convention Center -- Rm. 338/339, Oral
Division of Physical Chemistry |