Effects of Thermal Modification of Oak Wood Upon Selected Properties Of Coating Systems


Gurleyen L., AYATA Ü., Esteves B., Gurleyen T., ÇAKICIER N.

BIORESOURCES, cilt.14, sa.1, ss.1838-1849, 2019 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 14 Sayı: 1
  • Basım Tarihi: 2019
  • Doi Numarası: 10.15376/biores.14.1.1838-1849
  • Dergi Adı: BIORESOURCES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1838-1849
  • Anahtar Kelimeler: Parquet, Heat treatment, Oak, Glossiness, Color, Adhesion, PINE PINUS-SYLVESTRIS, HEAT-TREATMENT, COLOR CHANGES, DIMENSIONAL STABILITY, MECHANICAL-PROPERTIES, SURFACE-ROUGHNESS, ADHESION STRENGTH, BONDING STRENGTH, TREATED WOOD, UV VARNISH
  • Atatürk Üniversitesi Adresli: Evet

Özet

In the last few years there has been an increased demand to change the natural color of valuable hardwoods without chemicals for use mainly in indoor parquet floors. In this study, wood samples from oak (Quercus petraea L.), one of the most used species for parquet, were heat treated (ThermoWood method) at 190 degrees C for 2 h and at 212 degrees C for 1 and 2 h. Untreated and heat treated wood surfaces were coated following two different applications: type 1, with a single layer of sealer (50 g/m(2)) and type 2 with two layers (35 g/m(2)) using a nanolacke varnishing system. The objective of this study was to investigate surface properties including adhesion, glossiness, pendulum hardness, and color (L*, a*, b*,Delta E*,Delta L*, Delta a*, and Delta b*). With heat treatment the lightness decreases, and its decrease is higher for higher temperatures and treatment times. Type 2 coated wood presented a slightly lower lightness decrease. The experiment showed a slight increase followed by a decrease in redness (lower a*) and a clear decrease in the yellow tone (b*). The total color variation increased with the intensity of the treatment, while the glossiness decreased (more for Type 1 coated wood). The adhesion strength and surface hardness decreased with the heat treatment in both the Type 1 and Type 2 coated wood samples. The decrease in adhesion was higher for Type 2, reaching 67%, while the decrease in surface hardness reached about 18%.