Extending micro-contact printing for patterning complex polymer brush microstructures

As a fast developing soft lithographic technique, the development of micro-contact printing (μCP) has exceeded the original aim of replicating poly(dimethylsiloxane) (PDMS) stamp patterns. Here we exploited several extended μCP strategies with various printing conditions (over-force or swelling induced physical deformation, and UV-Ozone treated chemical surface modification to a PDMS stamp), combining with surface initiated atom transfer radical polymerization (SI-ATRP), to pattern complex poly(N-isopropylacrylamide) (PNIPAAM) brush microstructures. These series of μCP strategies avoid the need for expensive and sophisticated instrumentation in patterning complex polymer brush microstructures that do not exist on the original PDMS stamp.