PHOTOINDUCED AGGREGATION OF POLYTHIOPHENES Problem
Approach
• Solubilizing alkyl chains on conjugated • Link long alkyl chains to polymer backbone polymers are necessary to enable solutionthrough photocleavable groups. based processing of optoelectronic devices. • Soluble thin films of these materials, however, • Allows removal of solubilizing chains with light prevent all-solution multilayer film formation. • Other drawbacks of solubilizing chains: - Occupy space with inactive atoms - Increase rate of photochemical decomposition
Results Upon UV Photolysis Red Shift: Polymer Aggregates In Solution 0.06
Absorbance (OD)
0.05 0.04 0.03 0.02 0.01 0
300
400 500 600 Wavelength (nm)
700
Film Insoluble Upon UV Irradiation
Future Work and Applications • Extend to other materials such as donoracceptor polymers. • Demonstrate all-solution processed multilayer film • Photolithographic patterning of conjugated polymers. • Investigate observed red-shift of benzyl ester side-chains on optical properties of materials.
Samuel W. Thomas III Tufts University Department of Chemistry, Medford MA
