Physical and mechanical properties were evaluated on cross-laminated panels (plywood) fabricated with three plantation species (Cordia alliodora, Gmelina arborea and Vochysia ferruginea) from tropical climates in Costa Rica. The panels were glued with urea-formaldehyde resin modified with nanoclay at four concentrations (0,75; 1,00; 1,50 and 2,00 %) and unmodified resin. It was determined that ...

Urea-formaldehyde resins modified by melamine were synthesized by four catalysts (H2SO4, HCl, H3PO4, and NaOH/NH4OH) with a F/U/M molar ratio of 1.38/1/0.074. Resin structure and thermal behavior were studied by C-NMR and DSC techniques. For H2SO4, HCl, and H3PO4 catalysts, resins were prepared by two stage pH adjustment: the first pH stage was set at 1.25 (H3PO4 pH 1.60) and second pH stage wa...

in this study, hybrid of phenol formaldehyde-fish glue was used to replace the chemical resin in plywood manufacturing. for this purpose, fish glue was applied at three levels including 0, 10 and 20 percent based on the dry weight of resin. physical and mechanical properties of manufactured plywoods were measured. thickness swelling after 2 and 24 hours immersion in tap water, bending strength,...

ABSTRAKPanel kayu merupakan produk yang terbuat dari bahan direkatkan dengan menggunakan resin, perekat digunakan dalam produksi lapis resin urea-formaldehid (UF). Resin UF adalah thermosetting urea dan formaldehid akan mengeras jika dipanaskan dapat dicetak ulang. Pada penelitian ini, pembuatan baku Urea Formaldehyde Concentrate (UFC). Tujuan ini mempelajari pengaruh perubahan sifat kinerja UF...

Low mole ratio urea-melamine-formaldehyde (UMF) resins synthesized with 2.5% and 5.0% melamine levels added at the beginning, middle, and end points of the first alkaline step of the typical urea-formaldehyde (UF) resin synthesis procedure were compared with typical UMF resins synthesized with melamine additions made at the final alkaline step. Various resin analysis, particleboard preparation,...

The objective of this study was to investigate the effects of hot water extraction process on the dimensional stability of oriented strand composites. Aspen wood strands were extracted using various severity factor levels. Phenol formaldehyde and polymethylene diphenyl diisocyanate resins were used for production of the oriented strandboard panels. Six panel groups were produced from the extrac...