WOOD RESEARCH Volume 68, Number 1, 2023
Walter Charles Primus, Faizatul Azwa Zamri, Siti Hashimah Mohamad Hanif, Aaliyawani Ezzerin Sinin, Abdul Halim Shaari, Latifah Omar, and Osumanu Haruna Ahmed

Dependence of polyurethane content on physical and mechanical properties of wood fiber/palm kernel shell composites

Wood-based composites with different ratios of wood fiber (WF)/palm kernel shell (PKS) and polyurethane (PU) content have been prepared using the wet-process method. Samples of WF85/PKS15 and WF75/PKS25 were fabricated where each sample was applied with 20% and 70% of PU contents and its physical and mechanical properties had been studied. The physical results show that the samples with 70% of PU content were denser, had low porosity, low moisture content, and low water absorption. Surface morphology observation shows both series samples with high PU content tend to form tube-like shape with different diameter. In mechanical studies, generally, the sample with high PKS and PU possesses high flexural strength, flexural modulus, tensile strength, tensile modulus, and hardness. However, the increased of PKS content in the composite reduces the tensile strength for both samples with 20% and 70% of PU. The effects of the binder and palm kernel shell in the composite were also explained. Based on the Japanese Industrial Standard (JIS) A 5905 standard, the sample composites meet the requirement under medium density fiberboard (MDF) category and classified as board type 5 which suitable as furniture, house, and automotive interior design and construction materials.

WOOD RESEARCH Volume 62, Number 4, 2017
Mehmet Akgül, Birol Uner, Osman Çamlibel, and Ümit Ayata

Manufacture of medium density fiberboard (MDF) panels from agribased lignocellulosic biomass

Lignocellulosics fibers and commercially-manufactured-chip (Pinus sylvestris L., Fagus orientalis and Quercus robur L.) with 11% moisture conten twere used for the experiment. The mixingratios of lignocellulosics fibers was 20% which is from okra and tobaccos talks, hazelnut and walnuts hell, and pinecone for each mixture in preformed panel and commercially-manufactured-chip was 100 % for the control sample. A commercial ureaformaldehyde (UF) adhesive was used as a binder. The physical and mechanical properties such as density, thickness swelling (TS), bending strength (BS), modulus elasticity (MOE), internalbond (IB), screw holding ability (SHA) perpendicular to the plane of panel, Janka hardness perpendicular to the plane of panel properties of MDF were measured.The results indicated that all the panels met the general purpose-use requirements of TS-EN. Thus, our results suggest that biomass from different sources can be an alternative raw material for MDF manufacturing process.

WOOD RESEARCH Volume 65, Number 2, 2020
Osman Camlibel and Mehmet Akgul

Mechanical and physical properties of medium density fibreboard with calcite additive

In this study, it is investigated that are calcite filler can be used in the production of medium density fiberboard. Chips have been to the process of cooking for 4-5 minutes in Asplund defibrator with the vapor pressure of 7-7.5 bar, and 180ºC temperature. 1.5% paraffin and 1% ammonium sulphate to be pulverized is added to fibers on the output of defibrillator and blowline line. Calcite fillers are prepared in a separate tank in order to use calcite instead of lignocellulosic fibers in the production of 1 m³ MDF. After that, urea formaldehyde glue is prepared as three different solutions which include the calcite, respectively with 3% (20 kg.m-3), 6% (40 kg.m-3), 9% (60 kg.m-3). The fibers are dried to moisture of 8%-12%. This press applies temperature about 185-190°C and pressure about 32-34 kg.m-2 to the mixture material for 270 seconds during pressing time. MDF panels (2100 x 4900 x 18 mm) were produced in the process. Both mechanical and physical experiments are performed on boards which are produced.