Laser-Induced Surface Wrinkling On Polypyrrole Films And The Applications

As a typical conducting polymer,polypyrrole?PPy?has attracted increasing attention due to its excellent physical and chemical properties.However,it is a great challenge to fabricate micro/nanostructured PPy films by a simple and efficient method.In this thesis,a simple efficient laser-writing strategy was reported to fabricate hierarchical nested wrinkling microstructures on polypyrrole?PPy?film with surface multi-functionization,which was based on the photo-thermal effect of the PPy film.The PPy film was grown on a polydimethylsiloxane?PDMS?substrate via oxidation polymerization of pyrrole in an acid solution,accompanied with the occurrence of in-situ self-wrinkling to generate double-scale wavelength?i.e.,?₁ and?₂?of surface wrinkles.The subsequent laser exposure of the PPy/PDMS bilayer induced new surface wrinkling with a larger wavelength?i.e.,?₃?.Owing to the retention of the initial?₁ wrinkles,hierarchical nested wrinkles with the smaller?₁ wrinkles nested in the larger?₃ ones were obtained.The hierarchical microstructures were well tuned by the laser-irradiation time,laser-light power,film thickness,and substrate modulus.More importantly,the large-scale path-determinative fabrication of complex oriented wrinkling microstructures was realized by controlling the relative motion between the bilayer and the laser light.Combined with the laser writing-induced changes in the surface color,roughness and conductivity,these hierarchical nested wrinkling patterns of PPy films had great application potentials in the fields such as modulating surface wetting property and fabricating microcircuits,as demonstrated here.