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Li Y.,Northeast Forestry University | Liu Y.,Northeast Forestry University | Wang F.,Northeast Forestry University | Wang X.,FPInnovations Forintek Division
Fuhe Cailiao Xuebao/Acta Materiae Compositae Sinica

In order to prepare a polymer reinforced wood-based composite with excellent properties, a fast-growing wood, Populus ussuriensis Kom, and glycidyl methacrylate (GMA) as a difunctional monomer and methyl methacrylate (MMA) as an acrylate monomer were selected, and the monomers were impregnated into the porous structure of wood and further initiated by a catalyst-thermal treatment for their in situ polymerization. The composite's structure was characterized by SEM, FTIR and XRD, and its corresponding properties were also tested. The results show that the contact between polymers and wood cell walls is tight, and the interfacial interaction is strengthened after adding GMA. GMA fully reacts with the hydroxyl group on wood cell walls by its epoxy group, and reacts with MMA in a free radical copolymerization form by its double bond. The copolymer, P(GMA-co-MMA) is finally grafted onto wood cell walls in an amorphous form. The testing results of its properties show that the modulus of rupture (MOR), the dimensional stability, the decay resistance and the thermal stability of P(GMA-co-MMA)/wood are increased by 90.53%, 54.05%, 92.85% and 31°C compared with those of untreated wood, respectively. Source

Zhao J.,China Academy of Building Research | Wang X.-M.,FPInnovations Forintek Division | Chang J.M.,Beijing Forestry University | Yao Y.,China Academy of Building Research | Cui Q.,China Academy of Building Research
Composites Science and Technology

The sound insulation property of wood/used tire rubber composite panel (WRCP) was investigated. A four-microphone method was used to measure the sound transmission losses of three different composite panels: WRCP, commercial compound wooden floorboard and commercial wood-based particleboard. The WRCP was manufactured in the lab with commercial urea-formaldehyde (UF) and polymeric methylene diphenyl diisocyanate (PMDI) adhesives. The test results indicated that sound insulation property of WRCP is better than that of commercial compound wooden floorboard and wood-based particleboard. In addition, the acoustic insulation of WRCP is significantly affected by the amount of rubber crumbs and PMDI adhesive used in the composite. An increase in the usage of recycled tire rubber crumbs and the dosage of PMDI adhesive significantly improve the soundproof property of the WRCP. Moreover, the microstructure of WRCP was examined using a scanning electron microscope (SEM). The sound insulation effect is also dependant on the microstructure of the interface zone of wood/rubber and densification of WRCP. The continuous interfaces are formed in the presence of sufficient UF and PMDI adhesives resulted in better soundproof WRCP. © 2010 Elsevier Ltd. Source

Nybakk E.,Norwegian Forest And Landscape Institute | Crespell P.,FPInnovations Forintek Division | Hansen E.,Oregon State University
Silva Fennica

This study examines the relationships between firm financial performance and a) the climate for innovation and b) innovation strategy in the wood products industry. The focus is on the moderator effects of firm size, country of operation, and industry sector. Using a sample of 460 responses from chief executive officers and top managers of Norwegian and US firms, we conducted a regression analysis to probe for interaction effects. The sample included primary and secondary manufacturers of various sizes. Consistent with previous studies, we found a positive impact for both a climate for innovation and an innovation strategy on firm performance. In terms of moderation, only one interaction was found to be significant, representing a moderator effect of industry × size on the climate-performance relationship. Further testing showed that secondary, large manufacturers exhibited a weaker, yet still positive, relationship between climate for innovation and performance. This low level of significant interactions suggests stability of the relationship among the main factors depicted in the model, with important implications for managers and future research. These findings indicate that a positive climate for innovation and a management committed to innovation through an innovation strategy have a positive effect on the bottom line of wood products firms. This effect holds true regardless of industry, size, or country, so most firms can benefit from the implementation of these pro-innovation practices. Source

Han G.,Northeast Forestry University | Deng J.,FPInnovations Forintek Division | Zhang S.,665 East Mall | Bicho P.,800 Wesbrook Mall | Wu Q.,Louisiana State University
Industrial Crops and Products

Steam explosion treatments were used to modify straw fiber attributes for panel manufacturing. In particular, the effect of steam temperature and retention time on morphology, acidity, wettability, and ash and silicon contents of wheat straw was studied. After steam explosion treatments, proportion of large particles decreased, while fiber bundles increased. Higher steam temperature and longer retention time resulted in more homogeneous fiber-like material. The results showed that the pH value of the untreated wheat straw fiber was nearly 7 and the pH values and acid buffer capacities of straw were greatly reduced after steam explosion treatments. This indicated that the acidity of straw increased after steam explosion treatments. The dynamic contact angle of the straw before the treatment was nearly 90°, indicating that the straw material without treatment is more hydrophobic. After steam explosion treatments, the contact angle of straw was significantly reduced, showing that the surface wettability of the treated straw was improved. The ash and silicon contents of straw were also significantly reduced by steam explosion treatments. The improved acidity and wettabillity as well as decreased silicon content would contribute to the improved bondability between straw particles and water-soluble adhesive binders. © 2009 Elsevier B.V. All rights reserved. Source

Duchesne I.,FPInnovations Forintek Division | Duchesne I.,Laval University
Wood and Fiber Science

Color variations in paper birch wood were examined in boards sawn from sawlogs from 168 trees harvested from two different stands. Approximately 2250 boards were sawn from the logs. The within-tree variability was considered by looking at the effect of log quality and log height class on board color. Results show that neither the log quality nor the log height class had a significant effect on the proportion of discolored wood on the surface of the board. However, these log parameters had an effect on the wood colorimetric variables. Log position in the tree was found to significantly influence sapwood yellowness as well as discolored wood luminosity and redness. Log quality on the other hand significantly influenced only one colorimetric factor, sapwood redness. © 2010 by the Society of Wood Science and Technology. Source

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