WOOD RESEARCH Volume 70, Number 1, 2025
OSMAN ÇAMLIBEL and MURAT AYDIN

INFLUENCE OF PARAFFIN ON MDF PROPERTIES AT INDUSTRIAL SCALE

In this study, the effect of paraffin addition on the modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), water absorption (WA), and thickness swelling (TS) properties of fiberboard by density variations was evaluated. Higher mechanical properties were calculated for the paraffin-free board. MOR and MOE of the boards decreased with the increase in density, but not linearly; indeed, fluctuations were observed. Conversely, IB values were increased with the increase in density. The adverse effect of paraffin on the mechanical properties was almost eliminated with the increase in density, particularly for the 750 kg/m³ density profile, except for IB. The WA performance of the boards was significantly increased (58.8%) with the increase in density. Furthermore, advances with the density increase were uplifted by paraffin addition. However, when water repellency properties and advances in WA were taken into consideration, paraffin addition caused the opposite behavior for TS, but around 5.1% decrease in TS was achieved for the 750 kg/m³ density profile

WOOD RESEARCH Volume 62, Number 3, 2017
Hüseyin Sivrikaya, Ahmet Can, Ibrahim Tümen, and Deniz Aydemir

Weathering performance of wood treated with copper azole and water repellents

Water borne wood preservatives have been widely used for a long time in the protection of wood either in ground contact or above ground. Copper is still major biocide component used today in treatment plant for wood protection despite the environmental concerns over copper-rich preservative systems. On the other hand, water repellents are considered to be potential additives for biocides, resulting in the decreased moisture content, reduced biocide leaching and increased dimensional stabilization. In the present study, copper azole (CA) was used as wood preservatives to the natural weathering for 6, 12 and 24 months respectively. In addition, semitransparent wood stain was used as post treatment with CA, and paraffin and silicon additives were incorporated in to biocide to be water repellent. Paraffin additives reduced the retention values as compared to other formulations. The highest color change and gloss loss were obtained with Scots pine control samples within the six months. CA pretreatment before wood stain was promising by indicating the lowest color change. Color change was reduced by the increasing ratio in paraffin and silicone additives. Combination of CA with wood stain and silicon additive could reduce the copper leaching to some extent.