title: Poly (vinylidene fluoride) / Poly (acrylonitrile)-based Superior Hydrophobic Piezoelectric Solid Derived by Aligned Carbon Nanotube in Electrospinning: Fabrication, the Phase Conversion and Surface Energy.
abstract: Multifunctional materials have attracted many interests from both fundamental and practical aspects, such as field-effect transistor, electric protection, transducers and biosensor. Here we demonstrated the first superior hydrophobic piezoelectric surface based on the polymer blend of polyvinylidene fluoride (PVDF)-polyacrilonitrile (PAN) assisted with functionalized multiwalled nanotubes (MWNTs), by a modified electrospinning method. Typically the β-phase polyvinylidene fluoride (PVDF) was considered as the excellent piezoelectric and pyroelectric materials. However, polar β-phase of PVDF exhibited a natural high hydrophilicity. As a well-known fact, the wettability of the surface is dominated by two major factors: surface composition and surface roughness. The significant conversions derived by the incorporation of MWNTs, from nonpolar α-phase to highly polar β-phase of PVDF, were confirmed by FTIR. Meanwhile, the effects of MWNTs on the improvement of the roughness and the hydrophobicity of polymer blend were evaluated by atomic force microscopy (AFM) and contact angle (CA). Molar free energy of wetting of the polymer nanocomposite decreases with increasing the wt.% of MWNTs. All molar free energy of wetting of PVDF-PAN/MWNTs were negative, which means the non-wettability of film. The combination of surface roughness and low-surface-energy modification in nanostructured composites leads to high hydrophobicity. Particularly, fabrication of superior hydrophobic surfaces not only has fundamental interest but also various possible functional applications in micro- and nano-materials and devices.
authors.affiliation: Department of Chemistry, Faculty of Applied Science, Thamar University, P.O. Box 87246, Thamar, Yemen; Department of Chemistry, Oakland University, Rochester, Michigan 48309, United States.
authors.forename: Salem M
authors.initials: SM
authors.lastname: Aqeel
authors.affiliation: Department of Chemistry, Faculty of Applied Science, Thamar University, P.O. Box 87246, Thamar, Yemen; Chemistry Department, Xavier University of Louisiana, New Orleans, Louisiana, 70125, United States.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Chemistry Department, Xavier University of Louisiana, New Orleans, Louisiana, 70125, United States.
authors.forename: Lisa
authors.initials: L
authors.lastname: Than
authors.affiliation: Physics Department, Oakland University, Rochester, Michigan, 48309, United States.
authors.forename: Gollapudi
authors.initials: G
authors.lastname: Sreenivasulu
authors.affiliation: Department of Chemistry, Oakland University, Rochester, Michigan 48309, United States.
authors.forename: Xiangqun
authors.initials: X
authors.lastname: Zeng