WOOD RESEARCH Volume 69, Number 1, 2024
VLADIMÍR MANCEL, JOZEF KRILEK, IVETA ČABALOVÁ, ROMAN RÉH, MÁRIA OSVALDOVÁ, and ANNA DARABOŠOVÁ

EVALUATION OF SELECTED MECHANICAL AND PHYSICAL PROPERTIES OF PARTICLEBOARDS CONTAINING WASTE PLASTICS

This article is focused on the research of particleboards (PB) composed of wood particles from spruce logs and recycled crushed plastic granulates. Crushed plastic granulates sized from 1.0 to 4.0 mm were obtained from worn automobiles by recycling, specifically painted and unpainted bumpers. The proportion of plastic granulate in the particleboards represented 10%, 15%, and 20% of the total weight of the composites. In the production of PB, urea-formaldehyde resin and paraffin emulsion were used as a binder and ammonium nitrate was used as a hardener. The aim of the article was to compare the selected properties of PB containing plastic filler with pure PB. Mechanical properties (tensile and bending strength), and physical properties (water absorption and thickness swelling) were evaluated according to EN 319, EN 310 and EN 317. Based on the results, it can be stated that the bending strength and physical properties of PB containing plastic filler were significantly better compared to pure PB. On the contrary, the tensile strength values were lower in most cases

WOOD RESEARCH Volume 68, Number 4, 2023
Helena Hybská, Martina Mordáčová, Dagmar Samešová, and IVETA ČABALOVÁ

Ecotoxicological Tests of the Particleboards Containing Rubber Waste

The article is focused on the production and environmental evaluation of wood composites using waste rubber in the construction industry. Used aqueous extracts were prepared from the experimental wooden composites with various additions of the waste rubber from tires and waste seals. The pH value and organic pollution (by COD) were determined in the aqueous extracts. The effect on the environmental components (aquatic and terrestrial) was ecotoxicologically tested using the test organisms Sinapis alba, Lemna minor and Daphnia magna. Preliminary acute ecotoxicity tests were performed.

WOOD RESEARCH Volume 62, Number 3, 2017
Martin Zachar, Andrea Majlingová, Iveta Mitterová, and IVETA ČABALOVÁ

Influence of an age and damage of the oak wood on its fire risk

The aim of this work is to study the effects of different ages and damage of the oak wood (Quercus petraea Mattusch) in relation to its flash point temperature and ignition temperature, as well as on determination of the ratio of changes in extractives, cellulose and lignin, in the heat loaded samples of 5 – years old oak wood, 160 – years old oak wood, and also 160 – years old oak wood degraded by wood-destroying insects and fungi. The results of the analyses showed that the flash point temperatures were in the range of 357.52°C – 360.63°C.The ignition temperatures were at interval of 398.93°C – 414.92°C. The time to reach the ignition point was at the interval between 344 and 365 seconds. Under the thermal loading of oak wood, there comes to the significant changes, especially in the surface layers. These are, in addition to colour changes, demonstrated the chemical changes of the main components of wood and extractives. Increasing the temperature, there increases also the content of the substances extractable with ethanol and toluene. Increase in their amount is mainly due to the lignin, but partially also due to the polysaccharides decomposition products.