The research concerns the effects of variable magnitude magnetic field (0 9.4 Tesla) on the self-assembled morphology and domain orientation of conjugated rod-coil block copolymers (RC BCPs) in both bulk phase and thin film environments. The designed research activities include both theoretical 3-D self-consistent field calculations and rigorous experimental analysis of synthetically derived systems based on poly(3-hexylthiophene) (P3HT) and poly(phenylene vinylene) (PPV) derivatives, and are the product of a collaborative effort among three CSU faculty (Bailey, Wang, Meersman). The anticipated success of the proposal is based on the established experience of Profs. Bailey and Wang with block copolymer self-assembly, and the expertise of Prof. Meersman with high magnetic field instrumentation.
Intellectual Merit. Mounting evidence continues to highlight the critical importance of controlled nanoscale structure on the performance efficiency of conjugated polymer-based optoelectronic devices, such as LEDs, solar cells, and chemical and biological sensors. Exploiting the self-assembly of BCPs to generate nanoscale structure has long been recognized as a promising alternative to high cost lithographic processes. However, incorporation of rod-like conjugated polymers as constituent blocks in a BCP has been shown to have severe consequences on the phase behavior of such systems, the comprehensive nature of which has remained poorly understood due to limited synthetic access to such materials. However, on the heels of recent synthetic breakthroughs opening practical access to conjugated BCPs based on P3HT and PPV derivatives, the systematic unraveling of the phase behavior of these RC BCPs has now become viable. Our proposed investigations are based on a collaborative use of both theoretical and experimental analysis to strategically elucidate the rich complexity of
behavior in these systems, and more importantly, probe the potential of strong magnetic fields as processing tools to maximize domain alignment and minimize defect densities in this important class of soft materials.
Broader Impact. The scope of knowledge generated from these critically fundamental studies on the behavior of conjugated RC BCPs in the presence of strong magnetic fields will have direct and broad implications towards their integration into a range of technologically important application areas, including the fabrication of polymer-based photovoltaic cells, LEDs, chemical and biological sensors and field effect transistors. The interdisciplinary team of researchers assembled in this collaborative proposal (Bailey, Wang, and Meersman) represents two departments and two colleges at Colorado State University. The scope of work has been designed to capitalize on our strengths in synthetic and physical polymer chemistry, computational physics, and instrumentation for magnetic field generation. Thus, the collaboration between departments will strengthen and enhance the campus-wide infrastructure for future cross-cutting research-based graduate education. Modifications of existing superconducting magnets and design of inert gas sample chambers compatible with these magnets will provide lasting capabilities for the general study of magnetic field effects on structure in materials beyond those associated with this study. The results of the research activities will be integrated with our educational and diversity goals through a range of programs. These include regularly scheduled graduate and undergraduate level seminar series, special topics sections in our two polymer science courses, active undergraduate research programs, and a developing workshop series for regional (Colorado and Wyoming) high school science teachers on recent topics in nanotechnology, biotechnology, and biomaterials. Each of these programs actively focuses on maximizing participation of minority and underrepresented groups in the sciences, through close ties with CSU's outstanding diversity programs, including the Colorado PEAKS Alliance for Graduate Education and Professoriate Program (AGEP), the Louis Stokes Colorado Alliance for Minority Participation (LS CO-AMP), the Women and Minorities in Engineering Program (WMEP), as well as our student chapter of Society for Women in Engineering (SWE).
