Evaluation of urea formaldehyde (UF) as a surface coating material: Black pine wood and oriented strand board (OSB) coating by enhanced UF

Abstract

In this study, the applicability of a urea formaldehyde (UF) resin as a wood surface coater was investigated. Organic fillers were used in the resin solution to prevent crack formation on the surface covered with UF resin. Oriented strand board (OSB) and Black pine (Pinus nigra Arnold.) massive wood were used to prepare the samples. To prepare the control group, 4 g of ammonium sulfate (AS) was added to 100 g of UF and blended at 1000 rpm for 5 min. The first group was prepared using 5 g of wheat flour (WF) in 100 g UF as an organic filler. The second group was prepared by adding 5 g of cellulose fiber (CF) to a 100 g of glue solution, and the results were compared with those of the control group. The mechanical characterization of the samples (abrasion and scratch analysis) and staining analyses of the samples were determined according to the relevant standards. In addition, the samples were subjected to accelerated weathering by manually applying periodic moisturizing and drying. According to the results, the abrasion and scratch resistances of the black pine samples were higher than those of the OSB samples. Although the addition of WF reduced the abrasion and scratch resistance of the surfaces, it also eliminated the crack formation on the surface before weathering. The abrasion and scratch analysis results of boards coated with UF were much higher than those of the particleboards and fiberboards covered with decorative paper. The weathering process increased stain visibility in all samples, especially in the WF-added sample. After weathering, an approximately 30-40% decrease in scratch and wear resistance was observed in all the samples. As a result, it was concluded that UF can be used to coat the surfaces of wooden boards together with organic fillers in semi-outdoor environments.