Synthesis, Characterization of Biomimetic Electroactive Polyurethane Coatings and Their Application on Corrosion Protection

• Main Authors: Ting-Hsiu Chung, 鍾定修
• Other Authors: Jui-Ming Yeh
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/24066317803086694889

碩士 === 中原大學 === 化學研究所 === 103 === Abstract The successful preparation of high mechanical property and superhydrophobic structure electroactive polyurethane elastomer containing amine-capped aniline trimer (ACAT) is presented for the first time. First of all, ACAT was synthesized by carrying out oxidative coupling reactions between aniline and para-phenylenediamine, After which it was characterized through Fourier-transformation infrared (FTIR), electrospray ionization time-of-flight mass spetra (ESI-TOF Mass) and Nuclear Magnetic Resonance spectromter (NMR). Finally, the redox behavior of ACAT was further analyzed by cyclic voltammetric (CV). Subsequently, a polyurethane (PU) prepolymer was prepared by polymerizing diisocyanate of isophorone diisocyanate and diol of polyether. Electroactive polyurethane elastomer (EPU) was then produced by allowing the as-prepared polyurethane prepolymer to react with ACAT under suitable conditions. Non-electroactive polyurethane (NEPU) was also prepared polyurethane prepolymer to react with isophorondiamine (IPDA). Nanocasting technique was used to obtain a biomimetic superhydrophobic electroactive polyurethane (SEPU) surface structure from a natural Xanthosoma sagittifoliuim leaf. The superhydrophobic electroactive material could be used as advanced coatings that protect metals against corrosion. The morphology of the surface of the as-synthesized SEPU coating was investigated using scanning electron microscopy (SEM). The surface showed numerous micro mastoids, each decorated with many nano wrinkles. The water contact angle (CA) for the SEPU coating was 152.21°, which was significantly larger than that for the EPU coating (i.e., CA=58.75°). The significant increase in the contact angle indicated that the biomimetic morphology effectively repelled water. The developed SEPU coating exhibited superior anticorrosion performance on electrochemical corrosion tests as its corrosion rate is better than the bare steel substrate. The significantly-improved corrosion protection is attributed to, besides the steel substrate isolated by the coating, the synergistic effect of electroactivity and hydrophobic from the SEPU coating dwith the multi-scale structures mimicking the surface of Xanthosoma sagittifoliuim leaf.