The development of novel sound-absorbing and anti-corrosion composite coating

© The Electrochemical Society. The effects of addition of graphene on the corrosion protection and acoustic absorption performance of polyurethane (PU) coatings have been studied in this paper. The corrosion properties of the coatings were characterized by electrochemical impedance spectroscopy, potentiodynamic polarization curves, and salt spray testing. The acoustic absorption coefficient (α) was measured over the frequency range of 1-8 kHz by two-microphone impedance tube filled with water. The preliminary experimental results showed that PU/graphene nanocomposite coating exhibited a relatively high and stable impedance value during exposure to a 3.5 wt% NaCl for 168 hours, suggesting the presence of graphene can effectively improve corrosion resistance of the PU coating. Also, it was observed that PU/graphene nanocomposite coating had higher acoustic absorption coefficient and exhibited good absorption performance in the frequency range of 1000 Hz and 8000 Hz as the graphene content is 4 wt%.