UC Santa Barbara

Photochromic small molecules have long been of interest for their ability to translate small changes at the atomic level into an easily identified visual color change. These compounds allow the use of stimuli such as light or heat to cause a change a change in the conformation and thus the size and polarity of a molecule. In the reverse, they allow for changes such as heat and mechanical stress to be easily visualized at the macroscopic level through a color change. The general concept and background of these photo- and thermochromic molecules will be introduced. The synthesis and properties of two privileged classes of photochromic molecules, spiropyrans and donor-acceptor Stenhouse adducts (DASAs) will be discussed. These two compounds will be used extensively in the research in this dissertation. Next, the use of these compounds for sensing stress at high strain rates will be examined. Then the synthesis of novel DASAs with highly tunable absorption profiles will be discussed, along with their properties. This will be followed by a highly modular approach to the incorporation of DASAs into acrylate polymers. Finally, the effect of the acceptor group on the properties of the DASA will be examined.