Salt crystallization-assisted degradation of epoxy resin surface in simulated marine environments

[Display omitted] •Salt crystallization accelerates the degradation of epoxy in the surface layer.•UVA irradiation further exacerbates the salt crystallization effect.•There is a possible synergistic effect on epoxy degradation between the UVA irradiation and the NaCl solution wet-dry cycling.•The salt-accelerated UVA degradation may be employed to rapidly evaluate the performance of an epoxy resin coating. Epoxy resin samples were cyclically exposed to ultraviolet A (UVA) and a 5 wt% salt solution in a specially designed marine environment simulation system. Surface analyses indicated that UVA irradiation could accelerate the degradation of the epoxy surface and the dissolution of the degraded products, while the salt crystallization in the drying process could further accelerate the chalking and peeling of the degraded products. A possible synergistic effect between the UVA irradiation and salt crystallization was proposed to interpret the degradation, which may provide a new insight into the damage of organic polymer materials in marine environments.