Fabrication and Characterization of Hydrophobic Nylon-Cyanoacrylate Polymer Networks

A. Attanasio, I.S. Bayer, A. Athanassiou
Italian Institute of Technology, IT

Keywords: polymer networks, hydrophobicity, contact angle, wetting, nylon

Summary:

We report a simple and inexpensive method of fabricating novel hydrophobic polymer blend networks based on polyamide,known as nylon, and polyethylcyanoacrylate. The process is a single-step solution casting from a common solvent, formic acid. After casting and subsequent solvent evaporation, the in-situ polymerization of ethyl-cyanoacrylate monomer within the nylon forms nylon-polyethylcyanoacrylate interpenetrating network films. The IPNs demonstrate remarkable waterproof properties allowing wettability control by modulating ethyl-cyanoacrylate concentration. The maximum hydrophobicity is obtained for 35% ethyl-cyanoacrylate concentration in nylon. In contrast, pure nylon and PECA films obtained from formic acid solutions are highly water-absorbing and hydrophilic, respectively. Since PECA polymerization takes place directly within the nylon matrix, molecular interactions are better facilitated compared to conventional polymer blends which can reduce the presence of hydrophilic surface moieties rendering the blends hydrophobic. The wettability, morphology and thermo physical properties of the IPN blend films were characterized as a function of ethyl-cyanoacrylate concentration in nylon. The composites developed in this work take advantage of the properties of both polymers in a single material and above all, due to their hydrophobic nature and minimal water uptake, can extend the application range of nylon where resistance to water uptake is required.