Designing π-Conjugated Polymeric Nano- and Microstructures via Light Induced Chemistry

We report the synthesis and characterization of a new class of photoreactive conjugated polymers (M-n = 9300 g D = 1.24; M-n = 9100 g mol(-1), D = 1.23; M-n = 8800 gmol(-1), D = 1.24) consisting of functionalized polythiophene-containing photoresponsive groups, i.e. a polythiophene containing 4-hydroxy-2,5-dimethylbenzopherione (DMBP) (photoenol) and/or maleimide groups. We evidence the chemical versatility and platform character of the generated light reactive polythiaphenes in a range of examples by creating variable polythiophene functional 2D and 3D structures and morphologies. Single-chain nanoparticles and polymeric networks are formed by cross-linking of DMBP and maleimide containing polythiophene, via UV light irradiation by varying the polymer concentration. Maleimide-functionalized polythiophene is employed for spatially resolved functionalization of surfaces and the coating of preformed 3D polymeric microstructures via direct laser writing (DLW). The generated polythiophene functional materials are carefully characterized via size exclusion chromatography, dynamic light scattering, and time-of-flight secondary ion mass Spectrometry as well as FT-IR spectroscopy techniques.