New advances in the waterborne UV technology are placed in the perspective of the molecular weight of the polyacrylate molecule and the different stabilization mechanisms of the resulting waterborne colloids, ranging from emulsions to dispersions. The main characteristics of emulsions are presented with an emphasis on the parameters that govern the emulsification process and the colloidal stability of the final product. High-solid (65%) VOC-free emulsions with a low viscosity are delivering outstanding performances as hard coats for spray application on plastics. These emulsions can be blended to model radiation curable polymer dispersions either as such or after a proprietary transformation. It is thus possible to design complex dispersions with differentiated polymer particles resulting in coatings with specific tensile properties that can be analyzed by various elastic models. The best reinforcing effect is obtained when a composition gradient is formed between hard submicron-sized inclusions and the surrounding continuous matrix, as evidenced by advanced Atomic Force Microscopy methods. The coatings prepared using a multiple-phase pattern of hard and soft unsaturated polymeric components present distinct chemical and mechanical resistance benefits in pigmented systems. All the products meet the environmental expectations of today's coating industry.
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