Plasticity increase of beech veneer by steaming and gaseous ammonia treatment

Ammonia treatment was used in order to change the colour of wood and also to plasticize the wood before bending or compressing. The mechanism and the process of gaseous ammonia treatment impact on wood are not very well known. The goal of this study was to quantify the effect of gaseousammonia on mechanical properties, i.e., modulus of elasticity (MOE), modulus of rupture (MOR) and deflection at maximal loading force (yFmax). When wood was treated by water and ammonia vapour together, significant changes in plasticity of wood were observed. The samples which were firstlyexposed to water vapour and then to ammonia vapour exhibit the lowest values of MOE and MOR and an enhanced flexibility of the material. The results show that ammonia treatment increases wood plasticity. This process can be used for manufacturing of bent furniture

Aplikace nových materiálů pro tvorbu nábytku budoucnosti s ohledem na uživatelský komfort =:Aplication of new materials for furniture development with respect to user comfort /

This thesis was focused on solid wood surface treatments. The goal of the thesis was to achieve superhydrophobic behavior of solid wood surface and its application on furniture design – bathroom furniture. In the first part of experiment the thesis dealt with plasma discharge surface treatment of 3 different wood species – larch (Larix decidua), oak (Quercus robur) and pine (Pinus sylvestris). These treatments were performed in atmospheric and inert (nitrogen) environment with different time of treatment. Effect of plasma discharge was evaluated by contact angle measurement. The second part of the experiment was focused on wax deposition on wooden samples with different roughness. The wax n-hexatriacontane is naturally found as a component of wax blends on the surface of plant leaves. The deposition was performed by physical evaporation in vacuum. This wax has a self-assembly ability, e.g. it creates 3D objects on the surfaces after deposition. The dependence of roughness on self-assembly and wettability in time were examined. Self-assembly ability was observed with scanning electron microscopy and confocal microscopy. Plasmatic treatment hasn´t led to increased hydrophobicity, nevertheless, a significant increase of hydrophilicity was observed during contact angle measurement which could be used as a preparation for surface coating. Surface treatment with wax has led to significant increase of hydrophobicity. Samples of larch and oak achieved superhydrophobic surface behavior (CA > 150°) and pine samples achieved highly hydrophobic behavior (CA > 140°)

Plasticity increase of beech veneer by steaming and gaseous ammonia treatment

Ammonia treatment was used in order to change the colour of wood and also to plasticize the wood before bending or compressing. The mechanism and the process of gaseous ammonia treatment impact on wood are not very well known. The goal of this study was to quantify the effect of gaseousammonia on mechanical properties, i.e., modulus of elasticity (MOE), modulus of rupture (MOR) and deflection at maximal loading force (yFmax). When wood was treated by water and ammonia vapour together, significant changes in plasticity of wood were observed. The samples which were firstlyexposed to water vapour and then to ammonia vapour exhibit the lowest values of MOE and MOR and an enhanced flexibility of the material. The results show that ammonia treatment increases wood plasticity. This process can be used for manufacturing of bent furniture