Evaluation of Deterioration Mechanism of Materials with Petrolatum Lining that had been Exposed Long-term to the Marine Environment

Abstract

Materials with petrolatum lining that had been exposed to the actual environment for 10-30 years were collected, and a component analysis was conducted through FT-IR measurement and molecular weight distribution measurement and defect rate measurement to compare them with unused materials. These results clearly showed that petrolatum materials are decomposed into low molecules due to oxidization with the exposure time increases. Steel corrosion causes partial defects in anticorrosion materials, and particularly notable at splash zone. Degradation mechanism was confirmed through the defect rate measurement, and AC impedance measurement with simulated materials. The possibility of proposing degradation level curve created by utilizing the absorbance ratio obtained from the FT-IR analysis was found.