| 摘要 |
PURPOSE: To obtain a fundamental protective coating not depending on a barrier perfectly impermeable to an environment by annealing the coating of a cation- exchange polymer comprising a perfluorocarbon copolymer on a metal substrate so as to improve the rejection characteristics of hostile or obstructive anions by the copolymer to change the same morphologically. CONSTITUTION: A protective coating protects a metal substrate 2 from anionic corrosion but a metal itself must be protected from cationic corrosion. Under neutral and basic conditions of pH 5 or more, anionic corrosion is a main cause of corrosion and the protective coating 6 protects the metal substrate 2 from overall and localized corrosion, especially, localized corrosion. The perfluorocarbon copolymer used in the protective coating 6 is a cation-exchange polymer acting as a barrier against the movement of anions to or from the coated substrate. Further, the perfluorocarbon copolymer is annealed in order to improve permselectivity and the adhesion to the substrate 2. |
