Papers by Keyword: Beech Wood

Abstract: Modified wood fibre reinforced polypropylene composites at a wood fibre content of 50 wt. % are prepared using different types of wood fibres (beech wood refiner fibre, mercerised beech wood refiner fibre, mercerised and bleached beech wood refiner fibre as well as beech wood chips, mercerised beech wood chips, mercerised and bleached beech wood chips) to improve the impact resistance of the final composite. Additionally a beech wood refiner fibre-PP composite as well as a beech wood chip-PP composite are mixed with regenerated cellulosic fibres (5 wt. % and 10 wt. %) to further enhance the impact resistance. To increase the interfacial adhesion with the matrix and to improve the dispersion of particles two different coupling agents with contents from 2 wt. % to 8 wt. % are tested with two wood plastic composites (WPC). One is made of beech wood refiner fibres and the other one is produced from beech wood chips.The present study investigated Charpy impact property of wood fibres reinforced polypropylene as a function of fibre modification, content of regenerated cellulosic fibres and coupling agent.From the results it is observed that beech wood refiner fibre-PP composites show better Charpy impact properties than beech wood chips-PP composites. Charpy impact resistance is improved by mixing regenerated cellulose fibres (RCF) and RCF-PP-granule with beech wood refiner fibres and chips. The maximum increase in impact resistance is two times for refiner fibres and 10 % RCF-PP-granule respectively three and a half times for chips and 10 % RCF-PP-granule. By adding coupling agent Charpy impact resistance is nearly doubled for all wood fibre-PP composites.

Abstract: In this paper, adhesion of solid coatings to wood is assessed through interactions among surface forces at their phase boundary. The issue is treated on an example of beech wood and a priming UV lacquer. Our approach used analogy with the laws valid for the system solid – liquid. The results show that cohesion of wood > adhesion of coating to wood > cohesion of coating. This relation was also confirmed by the testing of mechanical loading in tension of the whole system.

Abstract: The aim of present work is monitoring thermal decomposition tested samples depending on distance of ignition source, subsequent generation of flame and flameless combustion. Tested samples are used to produce biofuel in form of pellets, which can be made of spruce wood (Picea excelsa, L.) and beech wood (Fagus sylvatica) and have a direct effect on the properties of these pellets. Measurements are carried out according to standard STN ISO 871:2010 Determination of ignition temperature using a hot-air furnace. External ignition source (electrically heated spiral of the wire canthal) is used to analyze different conditions of test samples. Distance between external ignition source and tested samples is 10, 50 and 90 mm. The experiments are performed at an air flow rate 38, 25, 12,5 and 0 mm.s^-1. The results show the rate of loss of weight and the flow rates of the material of the test samples at the different test conditions.

Abstract: This study quantified selected emissions (carbon monoxide and nitrogen oxides) that are produced during combustion of beech wood, birch wood and spruce wood charcoal in the combustion tube furnace. The maximum concentration of carbon monoxide and also the nitrogen oxides have been measured in the case of the spruce wood charcoal. The minimum concentration of carbon monoxide and also nitrogen oxides have been measured in the case of the beech wood charcoal. Although the difference between maximum emissions concentration of examined samples has been smooth. The comparison of obtained results with data published by previous studies can be made a suggestion, that the maximum concentrations of measured emissions are higher for wood than for charcoal. The nitrogen oxides yield per weight loss is higher for wood than for charcoal. On the other hand the carbon monoxide yield is higher for charcoal than for wood.