Layered Double Hydroxide Based Nano Composites For Highly Impact Resistant Coatings

摘要

@@Introduction In the past decades, one of the main environmental concerns in coatings technology has been the reduction of volatile organic compounds which today manifests itself in a high proportion of waterborne coatings. Recent trends to render industrial coatings processes more economic have led to leaner and thinner coatings systems. In order to maintain the coatings functionality in terms of substrate protection, the coatings impact resistance, e.g. stone chipping needs to be adapted; particularly strength, toughness, and limitation of crack propagation have to be improved. For instance waterborne automotive primers are based on tough polymers capable to form hydrogen bonds (e.g. polyurethanes) that are highly filled with inorganic micron-sized particles like titania, barite, and easily cleavable talc, which primarily cause cohesive failure of the coating upon impact. Additionally, in order to impart further functionalities to those layers like color effect (aesthetics) or corrosion inhibition (diffusion barrier, inhibitor release) it is required to increase the scope for formulation by reducing the loading with filler particles.