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Polymer composites with nanocellulose as the reinforcing agent often lack good compatibility between the two components. In this study, we have combined cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs) in different ratios to create all-cellulose films consisting of entirely discrete nanocellulose objects that complement each other. Then further, by applying the controlled dissolution concept we were able to create defined optical patterns on the films. The films consisting of 50% CNCs showed equivalent mechanical and barrier properties when compared to the pure CNF film. In addition, the incorporation of CNCs enabled tuning of the films' optical properties. To modify this film further, we prepared specific patterns on the film by controlled dissolution by impregnating the films with N-methylmorpholine-N-oxide (NMMO) followed by heat treatment and pressure. Mechanical testing and optical measurements of the patterned films showed the effect of the dissolved cellulose regions on the film properties. The controlled dissolution of the films increased the tensile strength of the films, however, the strain was decreased quite significantly. Altogether, the CNF/CNC hybrid films combine both nanomaterials' good properties. Cellulose nanofibrils have film-forming ability and incorporation of CNCs can further tune the optical, mechanical, and barrier properties, to optimize the films for varying applications such as optical sensors and packaging materials. [ABSTRACT FROM AUTHOR]

European Union has set a 70 % recycling goal for construction and demolition waste by 2020. In Finland, for example, 40 % of this waste is wood. The purpose of this study was to test the technical feasibility of pulping contaminated wood waste from the construction industry and using such pulps for fibre-based products outside of the conventional paper industry. It was found out that both chemical and thermo-mechanical pulping, and mechanical milling can be used for pulping contaminated wood waste chips received from construction waste treatment plant. The resulting pulps were then utilized successfully to prepare product demonstrations (wood fibre filaments and thick foam formed panel structures). There are no technical restraints for pulping contaminated construction wood waste, and the resulting pulp quality depends on the shape and size of the woodchips, dry content, wood species and type of contaminants. Although wood treated with copper preservatives can set special safety and process requirements, it does not necessarily impair the key properties of the final product. Graphical Abstract: [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]