Optically Transparent Polymeric Composite Films With Healability

Self-healing materials can heal damage with inherent materials to prolong lifetimes and improve the stability. Self-healing films have attracted much attention because the self-healing films can protect the the underlying substrates or endow the underlying substrates with special functions. In the past decade, great progress has been made on the research about the fabrication of self-healing films that can restore structural integrity and functions. However, there are only few reports on the fabrication of transparent self-healing films with functions. In this thesis, we focus on the fabriation of functional transparent self-healing films. This thesis also carries out initial exploration in the rapid fabrication of the transparent self-healing films.1. We present the fabrication of healable, highly transparent antifogging and frost-resisting polymeric coatings via the layer-by-layer assembly technique. Due to their remarkable water-absorbing capability, the highly transparent and flexible self-healing films show excellent antifogging and frost-resisting capabilities even under aggressive fogging and frosting conditions. Meanwhile, these films can repeatedly heal scratches and cuts several tens of micrometers deep and wide in the same region upon exposure to water because of the dynamic nature of the films.2. The erasable, optically transparent and healable films were fabricated by exponential layer-by-layer assembly technique. The hydrogen-bonded films are highly transparent, capable of conveniently healing damages and being erased under external stimuli. These films can heal damages such as scratches and deep cuts for multiple times in the same location by exposure to p H 2.5 water or humid N2 flow. The healability of these films originates from the reversibility of the hydrogen bonding interaction between the polymers, and the tendency of films to flow upon adsorption of water. When the damage exceeds the capability of the films to repair, the damaged films can be conveniently erased from substrates to facilitate the replacement of the damaged films with new ones.3. The flexible transparent self-healing polymeric complexes films were prepared by shaping the precipitates of polymeric complexes. These transparent polymeric complexes films can heal damage and restore mechanical property. The healability of the complexes films can successfully be imparted to adjacent films. The flexible films with good conductivity were prepared by depositing a layer of silver nanowires(Ag NWs) with high aspect ratio on top of the polymeric complexes films. Thanks to the self-healing ability of the polymeric complexes films, the damaged conductivity of these hybrid films can be healed by imparting the healability from polymeric complexes films to the layer of Ag NWs. Transparent conductive films can be furtherly prepared by reducing the thickness of Ag NWs layers.