Evaluation of Two Species of Soft Wood Decay Resistance for Heat-Treated Wood Using the Catalyst (H2SO4)

In Taiwan, it is important to maintain sustainable development of the forestry industry in order to raise the self-sufficiency of domestic timber. Japanese cedar (Cryptomeria D. Don and Formosa acacia (Acacia confusa Merr.(Leguminosae)) have abundant storage options and are the potential candidates for this purpose. Heat treatment is a new environment-friendly method used to enhance the dimensional stability and durability of wood. On treatment, a surface with new characteristics is produced because of wood component changes. Consequently, an inactivated surface and a weak boundary layer are generated, and the wettability for adhesives and coatings is reduced. Furthermore, it decreases the pH value of the wood surface, and results in delay or acceleration during the curing of adhesives. This phenomenon must be paid attention to for practical applications of heat-treated wood. Ideal heat-treated conditions of C. japonica and A. confusa woods with productive parameters such as temperature, holding time, heating rate, and thicknesses of wood were identified in our previous study. In this research work, we focus on the normal shear strength of heat-treated wood with adhesives such as urea-formaldehyde resin (UF) and polyvinyl acetate (PVAc), and the finishing performances of heat-treated wood with polyurethane (PU) and nitrocellulose lacquer (NC) coatings as well as assessing the decay-resistance of heat-treated wood. The results show that heat-treated wood had a better decay resistance than untreated wood. The mass decrease of heat-treated wood was only 1/3 or even less than the untreated wood. The normal shear strength of heat-treated wood with UF and PVAc decreased from 99% to 72% compared to the untreated wood, but the wood failure of heat-treated wood was higher than that of the untreated one. Furthermore, the adhesion and impact resistance of wood finished by PU and NC coatings showed no difference between the heat-treated wood and untreated wood. The finished heat-treated wood had a superior durability and better gloss retention and lightfastness than that of the untreated wood.

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Accelerated weathering and decay resistance of heat-treated wood reinforced polypropylene composites

Drvna industrija ◽

10.5552/drvind.2019.1851 ◽

2019 ◽

Vol 70 (3) ◽

pp. 279-285 ◽

Cited By ~ 1

Author(s):

Deniz Aydemir ◽

Mizgin Alsan ◽

Ahmet Can ◽

Ertugrul Altuntas ◽

Huseyin Sivrikaya

Keyword(s):

Treated Wood ◽

Decay Resistance ◽

Treatment Temperature ◽

Accelerated Weathering ◽

Sem Images ◽

Polypropylene Composites ◽

Color Changes ◽

Heat Treated ◽

Twin Screw ◽

Antifungal Efficiency

The aim of this study was to determine the accelerated weathering and decay resistance of the heattreated wood reinforced polypropylene composites (HT-WPC). Polypropylene (PP) was used as a matrix and the heat-treated wood treated at 180 °C and 220 °C as reinforcement filler. The effect of three filler type, such as 40, 60 and 100 mesh, on the outdoor performance of composites was also investigated. The composites were prepared with twin screw extruder, and the test samples were obtained with compression molding. Lightness index (L*), color changes (ΔE*) and physical changes on the surface of the composites after the accelerated weathering, and decay resistance of the composites were investigated. According to the results, the effects of heat-treated wood on color changes were found to be more than its filler size, and while the filler loadings were increased from 5 % to 20 %, it was determined to increase the color changes of the composites. In scanning electron microscopy (SEM) images, crack formation and deterioration on the surface of the composites were determined. In FTIR spectra, no difference was determined between the composites, and all peaks were similar to each one. The addition of heattreated wood improved the antifungal efficiency of the composite, and the mass losses decreased with the increasing of heat treatment temperature. As a result, adding heat-treated wood to PP was found to improve the outdoor performance of the HT-WPCs.

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Prediction of the decay resistance of heat treated wood on the basis of its elemental composition

Polymer Degradation and Stability ◽

10.1016/j.polymdegradstab.2009.10.013 ◽

2010 ◽

Vol 95 (1) ◽

pp. 94-97 ◽

Cited By ~ 28

Author(s):

Žiga Šušteršic ◽

Ahmed Mohareb ◽

Mounir Chaouch ◽

Mathieu Pétrissans ◽

Marko Petrič ◽

...

Keyword(s):

Elemental Composition ◽

Treated Wood ◽

Decay Resistance ◽

Heat Treated

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Physical, mechanical, and decay resistance properties of heat-treated wood by Besson® process of three European hardwood species

BASE - Numéro 3 ◽

10.25518/1780-4507.19050 ◽

2021 ◽

pp. 129-139

Author(s):

Maxime Ninane ◽

Caroline Pollet ◽

Jacques Hébert ◽

Benoit Jourez

Keyword(s):

Heat Treatment ◽

Axial Compression ◽

Modulus Of Elasticity ◽

Treated Wood ◽

Decay Resistance ◽

Strength Increase ◽

Promising Alternative ◽

Hardwood Species ◽

Heat Treated ◽

Impact Bending

Description of the subject. In Europe, the heat treatment of native wood species is gradually becoming an industrial reality. It provides a promising alternative to both the use of naturally durable, essentially tropical woods and the use of chemical preservative treatments based on biocides. Objectives. The aim of this study is to quantify the effect of heat treatment on the physico-mechanical and decay resistance properties of three native hardwood species (oak, ash, beech + steamed beech). Method. The wood was heat-treated in accordance with the Besson® process. The standard physical and mechanical tests including hardness, modulus of elasticity in static bending, static bending, axial compression, splitting and impact bending strengths, have been performed on 15 treated and 15 control associated samples for each species. The standard durability test on fungi exposed 60 treated and 60 control samples to each fungus. Results. The results show a decrease in the equilibrium moisture content and an increase in dimensional stability of heat-treated wood for the three species studied. The modulus of elasticity, hardness and axial compression strength increase slightly after the heat treatment, while static and impact bending strength and splitting strength may considerably decrease. The fungal durability of oak heartwood and ash increased until class 1, beech and steamed beech until class 3. Conclusions. The global approach of this study allows a complete and precise characterization of the technological properties of three native hardwood species after heat treatment. New uses of these native species can thus be explored.

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Effects of NH4Cl and MgCl2 on Heat Treatment and Evaluation of Decay Resistance Given to Heat-treated Wood

Journal of the Society of Materials Science Japan ◽

10.2472/jsms.70.522 ◽

2021 ◽

Vol 70 (7) ◽

pp. 522-527

Author(s):

Toru TANAKA ◽

Takafumi ITOH ◽

Yoriko IWAMOTO ◽

Yuka MIYOSHI ◽

Hiroaki HORIYAMA ◽

...

Keyword(s):

Heat Treatment ◽

Treated Wood ◽

Decay Resistance ◽

Heat Treated

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Meta‐analysis of anti‐swelling efficiency (ASE) of heat‐treated wood

European Journal of Wood and Wood Products ◽

10.1007/s00107-021-01691-5 ◽

2021 ◽

Author(s):

Tianyi Zhan ◽

Zhiting Liu ◽

Hui Peng ◽

Jiali Jiang ◽

Yaoli Zhang ◽

...

Keyword(s):

Meta Analysis ◽

Treated Wood ◽

Heat Treated

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Growth behavior of wood-destroying fungi in chemically modified wood: wood degradation and translocation of nitrogen compounds

Holzforschung ◽

10.1515/hf-2020-0252 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Lukas Emmerich ◽

Maja Bleckmann ◽

Sarah Strohbusch ◽

Christian Brischke ◽

Susanne Bollmus ◽

...

Keyword(s):

Protective Action ◽

Treated Wood ◽

Untreated Wood ◽

Brown Rot ◽

Decay Resistance ◽

White Rot ◽

Decay Fungi ◽

Chemically Modified ◽

Decay Tests ◽

Modified Wood

Abstract Chemical wood modification has been used to modify wood and improve its decay resistance. However, the mode of protective action is still not fully understood. Occasionally, outdoor products made from chemically modified timber (CMT) show internal decay while their outer shell remains intact. Hence, it was hypothesized that wood decay fungi may grow through CMT without losing their capability to degrade non-modified wood. This study aimed at developing a laboratory test set-up to investigate (1) whether decay fungi grow through CMT and (2) retain their ability to degrade non-modified wood. Acetylated and 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) treated wood were used in decay tests with modified ‘mantle specimens’ and untreated ‘core dowels’. It became evident that white rot (Trametes versicolor), brown rot (Coniophora puteana) and soft rot fungi can grow through CMT without losing their ability to degrade untreated wood. Consequently, full volume impregnation of wood with the modifying agent is required to achieve complete protection of wooden products. In decay tests with DMDHEU treated specimens, significant amounts of apparently non-fixated DMDHEU were translocated from modified mantle specimens to untreated wood cores. A diffusion-driven transport of nitrogen and DMDHEU seemed to be responsible for mass translocation during decay testing.

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Temperature-Dependent Creep Behavior and Quasi-Static Mechanical Properties of Heat-Treated Wood

Forests ◽

10.3390/f12080968 ◽

2021 ◽

Vol 12 (8) ◽

pp. 968

Author(s):

Dong Xing ◽

Xinzhou Wang ◽

Siqun Wang

Keyword(s):

Mechanical Properties ◽

Creep Behavior ◽

Cell Walls ◽

Treated Wood ◽

Crosslinking Reaction ◽

Depth Sensing ◽

Temperature Dependent ◽

Heat Treated ◽

Static Mechanical ◽

Static Mechanical Properties

In this paper, Berkovich depth-sensing indentation has been used to study the effects of the temperature-dependent quasi-static mechanical properties and creep deformation of heat-treated wood at temperatures from 20 °C to 180 °C. The characteristics of the load–depth curve, creep strain rate, creep compliance, and creep stress exponent of heat-treated wood are evaluated. The results showed that high temperature heat treatment improved the hardness of wood cell walls and reduced the creep rate of wood cell walls. This is mainly due to the improvement of the crystallinity of the cellulose, and the recondensation and crosslinking reaction of the lignocellulose structure. The Burgers model is well fitted to study the creep behavior of heat-treated wood cell walls under different temperatures.

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Bonding performance of heat treated wood with structural adhesives

European Journal of Wood and Wood Products ◽

10.1007/s00107-007-0218-0 ◽

2007 ◽

Vol 66 (3) ◽

pp. 173-180 ◽

Cited By ~ 21

Author(s):

Milan Sernek ◽

Michiel Boonstra ◽

Antonio Pizzi ◽

Aurelien Despres ◽

Philippe Gérardin

Keyword(s):

Treated Wood ◽

Structural Adhesives ◽

Bonding Performance ◽

Heat Treated

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Comparison of the color and weight change in Paulownia tomentosa and Pinus koraiensis wood heat-treated in hot oil and hot air

BioResources ◽

10.15376/biores.16.3.5574-5585 ◽

2021 ◽

Vol 16 (3) ◽

pp. 5574-5585

Author(s):

Intan Fajar Suri ◽

Jong Ho Kim ◽

Byantara Darsan Purusatama ◽

Go Un Yang ◽

Denni Prasetia ◽

...

Keyword(s):

Heat Treatment ◽

Color Change ◽

Treated Wood ◽

Pinus Koraiensis ◽

Weight Changes ◽

Paulownia Tomentosa ◽

Wood Color ◽

Color Changes ◽

Hot Air ◽

Heat Treated

Color changes were tested and compared for heat-treated Paulownia tomentosa and Pinus koraiensis wood treated with hot oil or hot air for further utilization of these species. Hot oil and hot air treatments were conducted at 180, 200, and 220 °C for 1, 2, and 3 h. Heat-treated wood color changes were determined using the CIE-Lab color system. Weight changes of the wood before and after heat treatment were also determined. The weight of the oil heat-treated wood increased considerably but it decreased in air heat-treated wood. The oil heat-treated samples showed a greater decrease in lightness (L*) than air heat-treated samples. A significant change in L* was observed in Paulownia tomentosa. The red/green chromaticity (a*) of both wood samples increased at 180 and 200 °C and slightly decreased at 220 °C. The yellow/blue chromaticity (b*) in both wood samples increased at 180 °C, but it rapidly decreased with increasing treatment durations at 200 and 220 °C. The overall color change (ΔE*) in both heat treatments increased with increasing temperature, being higher in Paulownia tomentosa than in Pinus koraiensis. In conclusion, oil heat treatment reduced treatment duration and was a more effective method than air heat treatment in improving wood color.

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