PROJECT ON HIATUS. APPLY TO RELATED BUT MORE FUNDAMENTAL PROJECT ON THE DYES IN MY LAB, OR TALK TO DR. MATT SMITH ABOUT HIS ENGINEERING PROJECTS IN PHOTOMECHANICAL MATERIALS.
My group will focus on the synthesis of organic photoswitches that are triggered by long-wavelength visible or near infrared (NIR) irradiation. A key feature will be the incorporation of functional groups enabling them to be incorporated into polymer networks via a variety of polymerization methodologies. The eventual goal is to develop NIR responsive polymeric materials for use in applications such as wireless "soft robotic" actuators, binary optical switches and positioners, or surfaces with morphing topologies.
Current light responsive azobenzene functionalized polymer networks enjoy several advantages as actuator candidates including large deformations, the ability to be remotely triggered, and highly tunable control via light intensity, polarization, wavelength and material alignments. One significant challenge hindering these materials from being employed in applications is their often relatively slow actuation rates and low power densities, especially in the absence of photo-thermal effects. In addition, current materials typically require high energy blue-green or uv lasers to trigger actuation, which hinders their usefulness for applications, especially in the biomedical field. To address this challenge we will develop NIR responsive materials that can exhibit robust mechanical deformations through photochemical switching of azobenzene moieties and also perhaps through cooperative photothermal effects. NIR is advantageous because of its low energy content and ability to penetrate deeply into biological tissues.
Students applying to this project should have an interest in doing primarily organic chemistry research, and should have at a minimum completed Organic I Lecture and Lab (CHEM 221 & 255 at Hope, or the equivalent elsewhere). The selected students will have the opportunity to gain familiarity with organic synthesis, photochemistry, polymers, and materials research. The student will also do all the characterization of structure and photophysical properties using NMR, UV-Vis, GC/MS and other techniques. If polymerizable molecules are successfully synthesized then the opportunity for material synthesis and photomechanical testing exists, in collaboration with the Smith group. (The Smith group will be developing the base polymer system and doing the preliminary materials engineering experiments in a tandem project this summer, but this SHARP project description refers primarily to the organic azo-monomer synthesis and characterization to be conducted predominantly in the Gillmore group.)
This is envisioned as a ten week paid summer project planned to be conducted from 5/11 - 7/17, but eight or nine week periods may be negotiable, as might starting as early as 5/4. Hope students on this project are encouraged (perhaps even expected) to begin during the spring semester (CHEM 490 for 0 or 1 credit, or by tying this research to a related CHEM 256B Organic Chemistry II Laboratory elective independent synthesis project.) Likewise there is a definite expectation for all Hope students to continue the work into the Fall semester as well, unless we reach a different understanding in advance.
This project is primarily intended for Hope College students, with preference for current group members. Applications from exceptional students from external institutions (particularly two-year college students considering transferring to Hope) may be considered if space and funding allow.
1. Y. Yang, R.P. Hughes, I. Aprahamian, Near-Infrared Light Activated Azo-BF2 Switches, J. Am. Chem. Soc. 2014, 136, 13190.
2. K.M. Lee, M.L. Smith, et al. Photodriven, Flexural-Torsional Oscillation of Glassy Azobenzene Liquid Crystal Polymer Networks, Adv. Funct. Mater. 2011, 21, 2913.