WOOD RESEARCH Volume 61, Number 3, 2016
Mehmet Yeniocak, Mehmet Colak, Osman Goktas, and Ibrahim Koca

Fire resistance performance of wood materials colored with eco-friendly pomegranate skin (Punica granatum) extracts

The main goal of this study was to determine fire resistance properties of wood treated with pomegranate extract and mordant mixes. According to that wood materials Scotch pine (Pinus sylvestris L.), Oriental beech (Fagus orientalis Lipsky) were chosen. Aluminum sulphate (KAl2(SO4)3.18H2O) copper sulphate (CuSO2.5H2O) and vinegar were used as mordant agent and a synthetic dye was used for comparison. Ultrasonic assisted method were used for extractionthe plant dyestuff from pomegranate skin (Punica granatum) and then applied to wood blocks by immersion (classic) and immersion ultrasonic assisted methods. The combustion test was realized according to ASTM-E 69-02 (2002) standard. The mass losses release of gasses (CO, O2) and the temperature differences of samples were detected for each 30 seconds during combustion. The results showed that the aluminum sulphate mixes were showed the best results on all tests. Unfortunately test performances are not enough to retard the fire effect on the wood materials. Eco-friendly natural colorant might be developed to use them as fire retardant.

WOOD RESEARCH Volume 61, Number 2, 2016
Mehmet Yeniocak, Osman Goktas, Ertan Ozen, and Ahmet Gecgel

Improving mechanical and physical properties of particleboard made from vine (Vitis vinifera L.) prunings by addition reinforcement materials

The main goal of this study was to improve mechanical and physical properties of particleboards made from vine (Vitis vinifera L.) prunings by addition of reinforcement materials. In Turkey, there are 462.000 hectare areas for vine cultivation. Annually, approximately 2.345.000 ton vine pruning parts residues are remained. Every season, large quantities of vine prunings are left as by-products in the fields, and unfortunately they are not utilized properly by the related industries. In this study, vine prunings and particles were used as raw material for three-layer flat pressed particleboards. Cord fabric fibre (CFF) (mixed), Cord fabric (CF) (sandwiched), plaster mesh (PM) (sandwiched), polyester fibre (PF) (sandwiched) were used as reinforcement materials. A commercial urea-formaldehyde (UF) resin was used as binder. Small size experimental panels (56x56x2 cm) were manufactured. Some physical properties (like, thickness swelling (TS), density, moisture content (MC) and mechanical properties (like, modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB) perpendicular screw-holding (PSH, ⊥), lateral screw-holding strengths (SHS, //), and tensile strength parallel to surface properties of panels were determined. The results indicated that some properties of the reinforced panels can give satisfactory values compared to control (non reinforcement) panels. Generally the reinforcement materials increased the mechanical properties of the particleboards. Such particleboards can meet the standards for isolation panels and interior-use.

WOOD RESEARCH Volume 63, Number 5, 2018
Mehmet Yeniocak and Suleyman Kahveci

Investigation leaching performance of wood materials coated with cotinus coggygria extracts and liquid glass (SiO2) mixture

The purpose of this study was to develop durable natural colorant modified with liquid glass (SiO2) to be used on wooden materials and determine their desorption performance using the leaching method. For this purpose, the natural colorant was extracted from the smoke tree (Cotinus coggygria) performing boiling method. Then, mordants; oak ash (3% by weight), and vinegar (10% by weight) (CH3COOH) were added to mixture. As the last, liquid glass (20% by weight) were added to mixture. The obtained mixture was applied to the Scots pine (Pinus sylvestris L.) and beech (Fagus orientalis) wood samples by using classic dipping and vacuum method. Leaching test was performed at pH3-22°C, at pH7-10°C, 22°C, 40°C and at pH 11-22°C. The results showed that the liquid glass did not protect wood materials in leaching as planned. The effective results can be obtained by changing the application method and amount of the liquid glass. The nature-based colorants can be an eco-friendly alternative to synthetics.

WOOD RESEARCH Volume 63, Number 3, 2018
Mehmet Yeniocak, Osman Goktas, Ertan Ozen, Mehmet Colak, and Mehmet Ugurlu

Determination of leaching features of wood surfaces colored by eco-friendly red beetroot (Beta vulgaris) extract

The aim of this study to develop an eco-friendly wood stain and to determine the adsorption and desorption on surfaces. In this context; plant dyestuff was extracted from the red beetroot by using ultrasonic assisted method and applied to wood blocks of Turkish oriental beech, Scots pine, oak, and walnut with immersion (classic) and ultrasonic-assisted immersion methods. As mordants, ferrous sulphate, aluminum sulphate, copper sulphate, and vinegar were chosen. In the study, the effect of such parameters as the medium pH (3, 7 and 9), temperature (22°C and 40°C), velocity of agitation (10 and 30 rpm) in leaching was investigated. As a result of experiments; red beetroot extracts performed good desorption, vinegar and copper sulphate were reduced the best desorption on surfaces. Ultrasonic-assisted method was not affect the leaching performance positively, but general leaching results showed that red beetroot can be used for wood surface stain and they can be alternative to chemical dyes.