Novel Design of Superhydrophobic and Anticorrosive PTFE and PAA + β − CD Composite Coating Deposited by Electrospinning, Spin Coating and Electrospraying Techniques

Abstract

A superhydrophobic composite coating consisting of polytetrafluoroethylene (PTFE) and poly(acrylic acid)+ β-cyclodextrin (PAA + β-CD) was prepared on an aluminum alloy AA 6061T6 substrate by a three-step process of electrospinnig, spin coating, and electrospraying. The electrospinning technique is used for the fabrication of a polymeric binder layer synthesized from PAA + β-CD. The superhydrophilic characteristic of the electrospun PAA + β-CD layer makes it suitable for the absorption of an aqueous suspension with PTFE particles in a spin-coating process, obtaining a hydrophobic behavior. Then, the electrospraying of a modified PTFE dispersion forms a layer of distributed PTFE particles, in which a strong bonding of the particles with each other and with the PTFE particles fixed in the PAA + β-CD fiber matrix results in a remarkable improvement of the particles adhesion to the substrate by different heat treatments. The experimental results corroborate the important role of obtaining hierarchical micro/nano multilevel structures for the optimization of superhydrophobic surfaces, leading to water contact angles above 170°, very low contact angle of hysteresis (CAH = 2°) and roll-off angle (< 5°). In addition, a superior corrosion resistance is obtained, generating a barrier to retain the electrolyte infiltration. This study may provide useful insights for a wide range of applications.

Icephobic Coating Based on Novel SLIPS Made of Infused PTFE Fibers for Aerospace Application

“…Finally, as can be observed, F(PTFE) does not present any contributions of PEO because of the HT 1 degradation process on the low PEO content present in the fibers. Moreover, the F(PTFE) shows the same spectra as the PTFE reference sample [ 49 ].…”

Anti-corrosion properties of bio-inspired surfaces: a systematic review of recent research developments

“…Vicente et al 130 deposited poly(acrylic acid) + β-cyclodextrin (PAA + β-CD) onto an aluminum alloy substrate using electrostatic spinning. They then obtained a PTFE layer by simple spin-coating, and finally, a layer of PTFE particles was electrosprayed to provide high roughness, resulting in a superhydrophobic coating with a hydrophobicity angle greater than 170°.…”