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The purpose of this study was to evaluate the feasibility of using highly filled powders as electrostatically applied paper coatings. Powders prepared by two different methods were suitable for electrostatic deposition and they attached to the paper surface with a grounded backing. Pressing at elevated temperatures turned out to be a crucial process step for improving the adhesive and cohesive strengths of the powder coating layer on paper. Limited mechanical interlocking with the base paper and an uneven pressure profile were factors impairing the surface strength of the coated paper. On the other hand, factors such as higher polymer content, higher pressing temperature, pre-heating the paper prior to coating, and increasing the number of hot roll nips increased adhesion between the coating and the base paper. Powder coatings as such had uneven thickness, and they displayed a relatively broad pore size distribution. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the feasibility of using highly filled powders with 100 parts per weight of calcium carbonate and 10 parts per weight of polymer, acting as binder, as electrostatically applied paper coatings. Such powders prepared by different methods were evaluated as being suitable for electrostatic coating. Powders compacted at elevated temperatures demonstrated cohesion superior to that of calcium carbonate, and at best similar to that of aqueous coatings. Cohesion, porosity and thus absorption properties of compacted powders were affected by the powder preparation method, compaction process, and powder composition. Powders containing semicrystalline polymer turned out to be the most interesting for further testing. [ABSTRACT FROM AUTHOR]

Novel nanostructured and high surface area tubular materials were produced combining electrospinning and atomic layer deposition processes with the removal of polymeric template via dissolution. The dissolution process changed the structure of the tube walls, and the smooth atomic layer deposition coating was transformed into a highly complex, coral-like structure. This material, which we have called 'nanocoral,' has a relatively high surface area, 323 m g, due to the interconnected cavities formed after the removal of the template. This kind of material has important potential applications, for example, in the fields of catalysts and filtration. [ABSTRACT FROM AUTHOR]