A Study On The Aging Behaviors Of Organic Coatings In Typical Atmosphere And The Correlation Between Outdoor Exposure And Laboratory Accelerated Experiments

Because of its economic and efficient properties, organic coatings largely and widely used have been one of main measurements of decreasing metal corrosion rate. However, organic coatings will be degraded in accordance with different mechanisms because of effects of sunshine (for example ultraviolet radiation), humidity, temperature etc. in atmosphere. The aging behaviors of organic coatings will change with different place and climate in actual use.Fluorocarbon coatings and Acrylic/polyurethane coating are used the research object in this paper. Steel samples coated with above coatings are exposed outdoor in typical atmospheres that are muggy and urban atmosphere in subtropical belt and semiarid atmosphere in plateau. After outdoor exposure, they are experimented on with different measures. Based on the experiment results, the aging behaviors of organic coatings and corrosion behaviors in interfacial between organic coating and metal can be gotten, and the effect degree of aging of organic coatings on corrosion resistance can be obtained. After accelerated experiments, the aging behaviors of organic coatings are analyzed basing on the result of different experiments, and the correlation between outdoor exposure experiments and QUV accelerated experiments are discussed.In addition, high polymer models, for instance Polyethylene (PE) and Polycarbonate (PC), are chose as the research objects in this paper. They are simultaneously exposed in above same atmosphere. After outdoor exposure, carbonyl group exponent of PE and differential absorbance at 290nm of PC can be measured. Based on above results, the effect of different atmosphere on organic coating can be compared quantitatively and the correlation between the aging of organic coating and the aging of above models are discussed.