Preparation And Environmental Stability Of Graphene Oxide Nanocomposite Films On PC Substrate

Polycarbonate?PC?transparent parts which have excellent performance and broad application prospects.With the expansion of PC to strategic fields such as high-end industrial products,aerospace and national defense,higher requirements have been placed on the safety performance and operational stability of products.However,PC is prone to aging degradation in complicated in real use environment?UV radiation,temperature-shock,force,etc.?.For the special service environment,coating and plating on the surface of PC is an effective way to enhance the substrate performance and slow down the aging behavior.It is of great significance and engineering value to develop a new type of protective film on PC surface,through film design and preparation of the membrane,explore the protective performance and stability mechanism of PC/film in service environment.In this paper,aiming to the aging failure of PC transparent parts in different service environments,polydopamine/graphene oxide?PDA/GO?hybrid film and silicone/modified graphene oxide hybrid film were prepared on the PC surface.Using the artificial ultraviolet accelerated aging,hot water aging and mechanical testing to study the environmental aging behavior of different membrane-based systems and discuss the protective effect of the films.The main work includes:?1?Graphene oxide was prepared by the Hummers method,and GO and PDA were further used as the assembly units,and the layer-by-layer self-assembly?LBL?was used to prepare?PDA/GO?LBL hybrid films on the PC surface.The structural properties and assembly of GO and?PDA/GO?_LBLfilms were characterized,the structural properties evolution and stability of?PDA/GO?_LBL/PC sample under ultraviolet irradiation and mechanical fatigue test were studied.The results showed that:The Hummers method successfully prepared graphene oxide nanosheets;and the PDA and GO achieved self-assembly on the PC surface,the obtained?PDA/GO?_LBLfilms has a certain ultraviolet absorption effect;It has good protecting under UV irradiation and slows down the aging of the substrate;Compared with the traditional commercial silicone coating,this films has better environmental stability and membrane base matching with PC.?2?The graphene oxide was modified with a silane coupling agent?GGO?and compounded with a silicone?Silicone?coating.The Silicone-GGO coating with excellent transparency was prepared on the PC surface,and used the environmental aging failure test to study the stability and protection mechanism of the coating.The results showed that:The degree of reaction between GGO and Silicone was investigated by controlling the reaction time of diethanolamine in the coating,and improved the dispersion of GGO in Silicone,obtain a coating with a smoother surface and lower haze;the coating has certain UV absorption and thermal stability due to the presence of GGO;The structure of the two-dimensional sheet can block the penetration of water molecules during hot water aging,and play a role in slowing down the aging of hot water;The structure can effectively transmit stress,"link"the coating to increase the scratch resistance.