Mechanical properties, components and decay resistance of Populus davidiana bioincised by Coriolus versicolor

2019 ◽  
Vol 31 (5) ◽  
pp. 2023-2029 ◽  
Author(s):  
Lulu Chang ◽  
Binbin Rong ◽  
Guoqi Xu ◽  
Qingkai Meng ◽  
Lihai Wang
Keyword(s):  
Mechanical Properties ◽  
Decay Resistance ◽  
Coriolus Versicolor ◽  
Populus Davidiana

scholarly journals Particleboards from Recycled Thermally Modified Wood

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1462
Author(s):  
Ján Iždinský ◽  
Zuzana Vidholdová ◽  
Ladislav Reinprecht
Keyword(s):  
Mechanical Properties ◽  
Urea Formaldehyde ◽  
Brown Rot ◽  
Decay Resistance ◽  
Raw Material ◽  
Modulus Of Rupture ◽  
Negative Effect ◽  
Serpula Lacrymans ◽  
Thermally Modified Wood ◽  
Modified Wood

In recent years, the production and consumption of thermally modified wood (TMW) has been increasing. Offcuts and other waste generated during TMWs processing into products, as well as already disposed products based on TMWs can be an input recycled raw material for production of particleboards (PBs). In a laboratory, 16 mm thick 3-layer PBs bonded with urea-formaldehyde (UF) resin were produced at 5.8 MPa, 240 °C and 8 s pressing factor. In PBs, the particles from fresh spruce wood and mixed particles from offcuts of pine, beech, and ash TMWs were combined in weight ratios of 100:0, 80:20, 50:50 and 0:100. Thickness swelling (TS) and water absorption (WA) of PBs decreased with increased portion of TMW particles, i.e., TS after 24 h maximally about 72.3% and WA after 24 h maximally about 64%. However, mechanical properties of PBs worsened proportionally with a higher content of recycled TMW—apparently, the modulus of rupture (MOR) up to 55.5% and internal bond (IB) up to 46.2%, while negative effect of TMW particles on the modulus of elasticity (MOE) was milder. Decay resistance of PBs to the brown-rot fungus Serpula lacrymans (Schumacher ex Fries) S.F.Gray increased if they contained TMW particles, maximally about 45%, while the mould resistance of PBs containing TMW particles improved only in the first days of test. In summary, the recycled TMW particles can improve the decay and water resistance of PBs exposed to higher humidity environment. However, worsening of their mechanical properties could appear, as well.

scholarly journals New Perspective on Wood Thermal Modification: Relevance between the Evolution of Chemical Structure and Physical-Mechanical Properties, and Online Analysis of Release of VOCs

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1145 ◽  
Author(s):  
Jiajia Xu ◽  
Yu Zhang ◽  
Yunfang Shen ◽  
Cong Li ◽  
Yanwei Wang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Dimensional Stability ◽  
Chemical Structure ◽  
Low Cost ◽  
Physical And Mechanical Properties ◽  
Decay Resistance ◽  
Thermal Modification ◽  
Infrared Spectrometry ◽  
Dominant Component ◽  
New Perspective

Thermal modification (TM) is an ecological and low-cost pretreated method to improve the dimensional stability and decay resistance of wood. This study systematically investigates the relevance between the evolution of chemical structure and the physical and mechanical properties during wood thermal modification processes. Moreover, the volatility of compounds (VOCs) was analyzed using a thermogravimetric analyzer coupled with Fourier transform infrared spectrometry (TGA-FTIR) and a pyrolizer coupled with gas chromatography/mass spectrometer (Py-GC/MS). With an increase of TM temperature, the anti-shrink efficiency and contact angle increased, while the equilibrium moisture content decreased. This result indicates that the dimensional stability improved markedly due to the reduction of hydrophilic hydroxyl (–OH). However, a slight decrease of the moduli of elasticity and of rupture was observed after TM due to the thermal degradation of hemicellulose and cellulose. Based on a TGA-FTIR analysis, the small molecular gaseous components were composed of H2O, CH4, CO2, and CO, where H2O was the dominant component with the highest absorbance intensity, i.e., 0.008 at 200 °C. Based on the Py-GC/MS analysis, the VOCs were shown to be mainly composed of acids, aldehydes, ketones, phenols, furans, alcohols, sugars, and esters, where acids were the dominant compounds, with a relative content of 37.05−42.77%.

Physico-mechanical properties and decay resistance of Cupressus spp. cement-bonded particleboards

2005 ◽  
Vol 27 (3) ◽  
pp. 333-338 ◽  
Author(s):  
Esmeralda Y.A. Okino ◽  
Mário R. de Souza ◽  
Marcos A.E. Santana ◽  
Marcus V.da S. Alves ◽  
Maria E. de Sousa ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Decay Resistance

Industrial Thermowood® and Termovuoto thermal modification of two hardwoods from Mozambique

Holzforschung ◽  
2018 ◽  
Vol 72 (8) ◽  
pp. 701-709 ◽  
Author(s):  
Michael Pockrandt ◽  
Mohamed Jebrane ◽  
Ignazia Cuccui ◽  
Ottaviano Allegretti ◽  
Ernesto Uetimane ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Acetic Acid ◽  
Shear Strength ◽  
Azadirachta Indica ◽  
Wood Decay ◽  
Vacuum Treatment ◽  
Decay Resistance ◽  
Thermal Modification ◽  
Steam Treatment ◽  
Carbohydrate Degradation

AbstractThe study aimed at treating metil (Sterculia appendiculataK. Schum) and neem (Azadirachta indicaA. Juss) timber from Mozambique under industrial conditions by steam [Thermowood®(TW)] and vacuum [Termovuoto (TV)] thermal modifications (TM). Matched boards were treated identically and wood alterations in chemistry, colour, mass loss (ML), mechanical properties and durability were compared. The applied vacuum partly removed the acetic acid that causes carbohydrate degradation, i.e. heat applied under vacuum was less destructive. TM under vacuum generated a lighter colour than that caused by steam treatment. ML was significantly higher after the TW process namely, 14.1 vs. 9.9% after thermo-vacuum treatment for metil and 14.2 and 12.1% for neem. Colour and ML changes correlated with the decrease in shear strength, rupture and elasticity moduli and increase in wood decay resistance. Metil wood is more permeable and demonstrated significant differences between the treatments; the thermo-vacuum process was less destructive but led to less improvement of durability compared to TW treatment.

Structure and Property of PGMA/Wood Composite

2009 ◽  
Vol 87-88 ◽  
pp. 456-461 ◽  
Author(s):  
Yong Feng Li ◽  
Yi Xing Liu ◽  
Jiang Tao Shi ◽  
Gang Li
Keyword(s):  
Mechanical Properties ◽  
Dimensional Stability ◽  
Cell Walls ◽  
Cellular Structure ◽  
Untreated Wood ◽  
Decay Resistance ◽  
Modulus Of Rupture ◽  
Test Results ◽  
Tight Contact ◽  
Wood Based Composite

In order to prepare a wood-based composite material which, as a type of multifunctional and natural bio-based material, possesses satisfactory mechanical properties, excellent durability (i.e., decay resistance and dimensional stability), and Aenvironmental characteristic, the study presents a new method which is based on the cellular structure of wood by initiating polymerizable monomers for in situ polymerization. Glycidyl methacrylate (GMA) as a multifunctional and polymerizable monomer was chosen, and impregnated into the porous structure of wood. After a thermal-catalyst process, the wood-based composite, PGMA/Wood, was prepared. The structure of this material was analyzed by SEM, FTIR and XRD; and its performance was also determined. The analyzing results show that GMA not only polymerized in the cellular structure in a solid form and amorphous form, which fully and uniformly filled in wood cell lumen, but also sufficiently grafted onto wood cell walls in a chemical level, resulting in tight contact between wood cell walls and resultant polymers (PGMA) without any obvious cracks. The test results of mechanical properties show that the modulus of rupture (MOR), modulus of elasticity (MOE), compression strength, and hardness of PGMA/Wood increased by 82%, 122%, 139%, and 348% over those of untreated wood, respectively. The test results of durability show that the dimensional stability and decay resistance of PGMA/Wood improved 44% and 91% than those of untreated wood, respectively. Such composite could be widely applied in the fields of construction, furniture and traffic.

scholarly journals Mechanical Properties and Decay Resistance ofcmd="newline"Hornbeam Cement Bonded Particleboards

2008 ◽  
Vol 2008 ◽  
pp. 1-4 ◽  
Author(s):  
Antonios N. Papadopoulos
Keyword(s):  
Mechanical Properties ◽  
Trametes Versicolor ◽  
White Rot Fungi ◽  
Decay Resistance ◽  
White Rot ◽  
Carpinus Betulus ◽  
Cement Ratio ◽  
Coniophora Puteana ◽  
Wood Particles ◽  
Minimum Requirements

Cement bonded particleboards were manufactured from hornbeam (Carpinus betulusL.) wood particles. Hydration tests were carried out to determine the inhibitory index in order to characterise wood-cement compatibility. The results revealed that the mixture of hornbeam-cement can be classified as moderate inhibition. Two wood: cement ratios were applied in this study, namely, 1 : 3 and 1 : 4, for the board manufacture. It was found that an increase of cement-wood ratio resulted in an improvement in all properties examined, except MOR. All properties of the boards made from 1 : 4 wood: cement ratio surpassed the minimum requirements set forth by the building type HZ code. Boards were exposed to brown and white rot fungi,Coniophora puteana, andTrametes versicolor, respectively. Overall, both fungi failed to attack the cement-bonded boards.

scholarly journals Hydrothermal Modification of Wood: A Review

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2612
Author(s):  
Md. Rowson Ali ◽  
Ummi Hani Abdullah ◽  
Zaidon Ashaari ◽  
Norul Hisham Hamid ◽  
Lee Seng Hua
Keyword(s):  
Mechanical Properties ◽  
Dimensional Stability ◽  
Elevated Temperatures ◽  
Chemical Properties ◽  
Treated Wood ◽  
Decay Resistance ◽  
Acoustic Properties ◽  
Buffer Solution ◽  
Promising Alternative ◽  
Hydrothermal Modification

Wood is a versatile material that is used for various purposes due to its good properties, such as its aesthetic properties, acoustic properties, mechanical properties, thermal properties, etc. Its poor dimensional stability and low natural durability are the main obstacles that limit its use in mechanical applications. Therefore, modification is needed to improve these properties. The hydrothermal modification of wood exposes wood samples to elevated temperatures and pressure levels by using steam, water, or a buffer solution as the treating medium, or by using superheated steam. Abundant studies regarding hydrothermally treated wood were carried out, but the negative effect on the wood’s strength is one of the limitations. This is a method that boosts the dimensional stability and improves the decay resistance of wood with minimal decrements of the strength properties. As an ecofriendly and cost-effective method, the hydrothermal modification of wood is also a promising alternative to conventional chemical techniques for treating wood. Researchers are attracted to the hydrothermal modification process because of its unique qualities in treating wood. There are many scientific articles on the hydrothermal modification of wood, and many aspects of hydrothermal modification are summarized in review papers in this field. This paper reviews the hydrothermally modified mechanical properties of wood and their potential applications. Furthermore, this article reviews the effects of hydrothermal modification on the various properties of wood, such as the dimensional stability, chemical properties, and durability against termites and fungi. The merits and demerits of hydrothermal wood modification, the effectiveness of using different media in hydrothermal modification, and its comparison with other treating techniques are discussed.

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