EFFECTS OF CHEMICAL COMPOSITION OF WOOD AND RESIN TYPE ON PROPERTIES OF PARTICLEBOARD
Nadir Ayrilmis, Gökay Nemli, Mehmet Baharoğlu, Esat Gümüşkaya, Selahattin Bardak
The effects of chemical composition of various wood species and resin type on the dimensional stability, mechanical properties, and formaldehyde emission of particleboard were investigated. The solubility in cold and hot water, NaOH, and alcohol-benzene were evaluated, as well as the amount of cellulose, α- cellulose, holocellulose, hemicelluloses, and lignin and the acidity (pH) of the wood particles after the chipping process. The chemical compositions of wood and resin type were the main parameters influencing physical properties, mechanical properties, and formaldehyde emission of particleboard. While high cellulose and α-cellulose content resulted in superior mechanical properties, high hemicelluloses content was detrimental to the mechanical properties and dimensional stability and increased the thickness swelling. The extractives dissolving in cold and hot water decreased the formaldehyde emission of particleboard. Hemicelluloses were found to be effective at lowering formaldehyde emission. High hemicelluloses content caused lower formaldehyde releasing. Extractives dissolving in the NaOH and alcohol-benzene positively affected the dimensional stability of particleboard panels. Resin type was found to have an effect on all of the properties of particleboard. Particleboards produced with melamine-urea formaldehyde resin showed better quality properties and lower formaldehyde emission compared to the particleboards produced with urea-formaldehyde resin.
Particleboard; Mechanical properties; Physical properties; Chemical compounds; Formaldehyde emission; Resin type