pH Sensitive Hierarchically Self-Organized Bioinspired Films

✍ Scribed by Pierre Escalé; Laurent Rubatat; Christophe Derail; Maud Save; Laurent Billon

• Book ID: 102497664
• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 377 KB
• Volume: 32
• Category: Article
• ISSN: 1022-1336
• DOI: 10.1002/marc.201100296

✦ Synopsis

Abstract

In the present manuscript, we have demonstrated that hierarchically structured smart porous polymer films based on honeycomb‐patterned surface can be elaborated from PS‐b‐P4VP pH‐responsive block copolymer using the breath figure process. Despite the fast film formation by a bottom‐up process, the copolymer nanostructuration was observed inside the walls of the honeycomb porous film. Atomic force microscopy (AFM), small angle X‐ray and neutron scattering (SAXS and SANS) measurements were used to reveal both the hexagonal arrays formed by the pores at the micrometer length scale and the hexagonal copolymer self‐assembly at the nanometer length scale.

Contact angle (CA) measurements were used to point out the reversible pH‐responsive wettability character of the surface. The PS‐b‐P4VP honeycomb film shows a contact angle variation of 20° between pH 9 and pH 3. An increase of the roughness was obtained with the pincushions hexagonal array enhancing the pH responsiveness of the polymer film with a switching CA gap of 75° when pH tuned from pH 9 to pH 3. This work presents the first report on honeycomb porous and pincushion films exhibiting a reversible pH‐responsive character. magnified image