Xiang-Ming Wang

Surface modification of poplar veneer by means of radio frequency oxygen plasma (RF-OP) to improve interfacial adhesion with urea-formaldehyde resin

Abstract The radio frequency oxygen plasma (RF-OP) treatment of wood was in focus, namely the surface properties of poplar veneer has been analyzed as a function of RF-OP treatment power concerning the chemical composition, free radicals, morphology and roughness. In addition, the interfacial adhesion of plywood composites was measured by determining the shear strength. The results show that RF-OP treatment introduced free radicals and polar groups onto the veneer surface, changed the surface morphology, and increased the surface roughness. Shear strength of the composite was improved. It can be concluded that RF-OP treatment is most effective at the optimal treatment power of 200 W.

Fungus-Modified Lignin and Its Use in Wood Adhesive for Manufacturing Wood Composites*

Abstract Organosolv lignins were modified with different fungal species. The modified lignins were used as raw materials for preparing lignin-phenol-formaldehyde (LPF) resins. Oriented strandboard ...

Optimizing Manufacturing Conditions for Durable Composite Panels with Eastern White Cedar and Aspen Strands

This study aimed to optimize manufacturing conditions when utilizing eastern white cedar (Thuja occidentalis L.) to increase the durability of structural panels with aspen (Populus tremuloides Mich...

Protecting Aspen Oriented Strand Board Panels from Biodegradation with White Cedar Extracts and Coatings

Eastern white cedar (Thuja occidentalis L.) is a naturally durable wood species due to toxic compounds present in the heartwood. These compounds may serve as natural fungicides to protect nondurable wood products from biodegradation. This study was intended to improve the effectiveness of posttreating aspen oriented strand board (OSB) panels with white cedar heartwood extracts against mold and decay by co-applying a protective coating. The results showed that aspen OSB samples treated with the white cedar water-soluble heartwood extracts had little mold infection. No mold growth was detected on any samples that were dip treated with the extracts and then brushed with a coating. The decay test showed that most samples treated with both white cedar heartwood extracts and a coating had significantly less weight loss than untreated control samples. Using coating products alone also reduced mold and decay growth on OSB samples; however, adding cedar extracts to the treatment significantly improved the performance of one of the three coating products tested against mold and decay.

Manufacturing Medium-Density Particleboards from Wood–Bark Mixture and Different Adhesive Systems*

Abstract The disposal problem of bark residues and the shortage of wood raw material supply in some regions make the use of bark an attractive option for the industry. In this study, medium-density particleboards were manufactured from mixed black spruce bark and spruce-pine-fir wood particles at a weight ratio of 50/50. Different adhesive systems were used as binders for the bark-based panels, including commercial phenol-formaldehyde (PF), urea-formaldehyde (UF), polymeric methylene diphenyl diisocyanate (pMDI) resins, and a laboratory-synthesized lignin-PF resin containing 30 wt% lignin substitution for phenol. The objective was to investigate the suitability of utilizing bark residues in the manufacture of particleboards for the floor underlayment (PBU) application. The resulting boards were evaluated according to the ANSI A208.1‐2009 standard for internal bond (IB), modulus of rupture, modulus of elasticity, hardness, thickness swell, and linear expansion. The test results indicate that all panels mad...