STUDY ON THE PROPERTIES OF POLYASPARTIC POLYUREA COATED CONCRETE UNDER SALT FOG EXPOSURE

摘要

Coating protection becomes the primary and available method for the protection of marine concrete. Polyaspartic ester (PAE) poly urea is a new aliphatic polyurea. In the present study, the frost resistance property and adhesion property of 4 different PAE polyurea coated concrete under salt fog exposure were studied for the first time. The surface morphology and molecular structure of the coating under the salt fog exposure were investigated through SEM and FTIR. The investigations on the influence of the salt fog exposure to the PAE-t-HDI prepolymer-D2000H65 PAE polyurea (T3) coated concrete PAE-b-H12MDI prepolymerH66 PAE polyurea (B2 coated concrete PAE-f-H12MDI prepolymerH62 PAE polyurea F2 coated concrete and T3 finishing coat/MDI emulsion primer PAE polyurea (TM) coated concrete reported that after 300 days salt fog exposure, the relative dynamic elastic modulus of T3 TM coated concrete were more than 85%, and the wet adhesion varied over the range of 1.0 2.5N/mm. SEM and FTIR researches show that no obvious changes were observed in the surface morphology and structure of the coating after 200 days salt fog exposure. The results indicate that PAE polyurea coated concretes have favorable salt fog resistance, and are suitalbe for applying in marine concrete structures.