Superhydrophobic fluorinated acylonitrile coatings via electrospraying

Abstract

The electrospraying of copolymers containing fluorinated acrylate and arylonitrile with different composition ratios was performed. Copolymers of 3,5-bis(perfluorobenzyloxy)benzyl acrylate (FM) monomer with arylonitrile (AN) were synthesized via free radical polymerization at 75 °C in dimethyformamide (DMF) using 2,2′-azobisisobutyronitrile (AIBN) as the initiator. Extended Kelen-Tudos (EKT) method was utilized to calculate the monomer reactivity ratios. For the used monomer pair r1 was found as 0.11 for AN and r2 was found as 0.93 for FM. The result of r1.r2 < 1 indicates that the reaction went forward as random copolymerization. Molecular weights of the obtained copolymers were determined by gel permeation chromatography (GPC). 1H NMR spectroscopy is used for the characterization of the copolymers. The thermal behaviors of the copolymers were analyzed by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Copolymers showed one glass-transition temperature changing on the copolymer composition which indicated that copolymers were amorphous. Contact angle values of ethylene glycol and water on the films which were prepared by electrospraying process indicated superhydrophobic character. The crystallinity and surface morphology of the copolymers were described by X-ray diffraction (XRD) and scanning electron microscope (SEM) respectively.