Molecular Control of Macromolecular Properties
- Author(s): Holcombe, Thomas
- Advisor(s): Frechet, Jean M. J.
- et al.
Molecular level control over macromolecules has been at the heart of human advancement, long before Hermann Staudinger coined the term Makromoleküle. From the development of primitive pharmaceuticals to the advanced materials that sent Man into outer-space, We have been tinkering with God's paint since our inception.
The work described herein primarily involves advances concerning poly-aromatic macromolecules for use in future electronic applications, particularly that of organic photovoltaics. There is a final chapter, however, that gives the reader a taste of how some molecular level changes can be directly visualized with modern microscopy techniques.
Chapter 1 provides a very brief introduction to conjugated polymers and molecular level control over macromolecular properties. Chapters 2 - 4 introduces the concept of polymer substitution as a means by which to control and improve charge generation in organic photovoltaic devices. Chapters 5 and 6 show how these polymers can take on larger, defined structures, yet are still beholden to intrinsic molecular properties - such as regioregularity, a fancy word for the regularity of the position in which two aromatic rings are joined together. Chapter 7 re-examines the role of polymer substitution on photovoltaic performance, this time with an emphasis on homo-polymer packing rather than electron transfer at the donor/acceptor interface. Finally, Chapter 8 visualizes how controlling the environment about a single metal atom can lead directly to a cyclic polyolefin. Individually, these advances do not yield any breakthroughs noticeable to a general audience; collectively, they sit atop a mountain of human knowledge, waiting to provide a stepping stone for the next generation.