A smart surface prepared using the switchable superhydrophobicity of neat electrospun intrinsically electroactive polyimide fiber mats

An electroactive polyimide fiber (EPF) mat based on conjugated segments of electroactive amino-capped aniline trimer (ACAT) as a diamine and 4,4′-(4,4′-sopropylidenediphenoxy)-bis(phthalic anhydride) (BSAA) as a dianhydride was successfully prepared by electro-spin technology with electrochemical activity and dopable properties, which were similar to polyaniline. The degree of electrochemical activity and dopable properties can be tuned by varying the content of ACAT existing in the as-prepared electro-spun EPF mats. After doping with perfluorooctanesulfonic acid (PFOS), the water contact angle of EPF surface is increased from hydrophobicity at 133° to superhydrophobicity at 155°. It is interesting that the EPF mat undergoes a switchable process from superhydrophobicity to superhydrophilicity via doping with PFOS and de-doping with ammonium gas.