Influence of Heat Treatment on the Water Uptake Behavior of Wood

Zhang, Yang; Xu, Deliang; Ma, Libo; Wang, Siqun; Liu, Xiang

doi:10.15376/biores.12.1.1697-1705

Cited by 17 publications

(19 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The peak found at 1890 nm (in raw spectra) is most likely a combination of bound water and hemicelluloses; this peak was greatly reduced in EAPS and APS following drying. HWE results in decreased hygroscopicity, which explains the decreased absorption band intensity for EAPS [44]. This reduction in hygroscopicity is related to the removal of hemicellulose sugars, which represent the most hydrophilic constituent of lignocellulosics.…”

Section: Near Infrared Spectroscopy (Nirs) Of Aps and Eapsmentioning

confidence: 99%

Chemical Composition of Apricot Pit Shells and Effect of Hot-Water Extraction

et al. 2015

View full text Add to dashboard Cite

Abstract:Agricultural residues, such as corn stover, wheat straw, and nut shells show promise as feedstocks for lignocellulosic biorefinery due to their relatively high polysaccharide content and low or no nutritional value for human consumption. Apricot pit shells (APS) were studied in this work to assess their potential for use in a biorefinery. Hot water extraction (HWE; 160 °C, 2 h), proposed to remove easily accessible hemicelluloses, was performed to evaluate the susceptibility of APS to this mild pretreatment process. The chemical composition of APS before and after HWE (EAPS) was analyzed by standard methods and 1 H-NMR. A low yield of the remaining HW-extracted APS (~59%) indicated that APS are highly susceptible to this pretreatment method. activity (AOA) of APS extracts was also undertaken. AOA of organic APS extracts were shown to be more than 20 times higher than that of a synthetic antioxidizing agent.

show abstract

Section: Near Infrared Spectroscopy (Nirs) Of Aps and Eapsmentioning

confidence: 99%

Chemical Composition of Apricot Pit Shells and Effect of Hot-Water Extraction

et al. 2015

View full text Add to dashboard Cite

show abstract

“…High temperature reduces the EMC of wood [60], the veneer and, as a consequence, TS of plywood panels made from veneer [27]. Zhang et al [61] showed that changing the character of wood from hydrophilic to more hydrophobic by extracting hemicellulose can also potentially improve the dimensional stability of wood and wood composites. It is known that heat treatment causes a decrease in affinity of the treated material to water.…”

Section: Water Absorption and Thickness Swelling Of Plywood Samplesmentioning

confidence: 99%

Effect of Veneer-Drying Temperature on Selected Properties and Formaldehyde Emission of Birch Plywood

2020

View full text Add to dashboard Cite

In this study, the effect of the veneer-drying process at elevated temperatures on selected properties and formaldehyde emission of plywood panels was determined. We assume that during the veneer drying at high temperatures, more formaldehyde is released from it, and therefore, a lower formaldehyde emission can be expected from the finished plywood. Prior to bonding, birch veneers were dried at 160 °C (control) and 185 °C in an industrial veneer steam dryer (SD) and at 180 °C, 240 °C and 280 °C in an industrial veneer gas dryer (GD). Two types of adhesives were used: urea–formaldehyde (UF) and phenol–formaldehyde (PF) resins. Bonding quality, bending strength and modulus of elasticity in bending, water absorption and thickness swelling of plywood samples were determined. The formaldehyde emission level of samples was also measured. It was concluded from the study that the effects of veneer-drying temperatures on the bonding strength and physical and mechanical properties of plywood panels were significant. Veneer-drying temperatures of 185 °C/SD, 180 °C/GD and 240 °C/GD negatively affected the bending strength and the modulus of elasticity along and across the fibres for both UF and PF plywood samples. Bonding strength mean values obtained from all test panels were above the required value (1.0 MPa) indicated in EN 314-2 standard. The lowest formaldehyde emissions for the UF and PF plywood samples were observed in the samples from veneer dried in a steam dryer at 185 °C/SD.

show abstract

“…e level of change depends on the wood species, type of heat treatment, treatment intensity, and process conditions, in which the temperature and the absence of oxygen play an important role [15]. As a result of these changes heat-treated wood has lower hygroscopicity [10,14,15], liquid water uptake [19][20][21][22][23], and consequently reduced dimensional changes. Besides, it was shown that the heat-treated wood has changed acidity, wettability, surface free energy, and anatomical structure.…”

Section: Heat-treated Wood As a Substrate For Coatingsmentioning

confidence: 99%

Heat-Treated Wood as a Substrate for Coatings, Weathering of Heat-Treated Wood, and Coating Performance on Heat-Treated Wood

Jirouš-Rajković

Miklečić

2019

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

Heat treatment is a method of wood modification with increasing market acceptance in Europe. The major patented European commercial heat treatment processes have trade names ThermoWood, Platowood, Retiwood, Le Bois Perdure, and Oil-Heat-Treated Wood (OHT). To what extent modification of wood affects the resistance of wood to weathering is also an important aspect for wood applications, especially where appearance is important. Unfortunately, heat-treated wood has poor resistance to weathering, and surface treatment with coatings is required for both protection and aesthetic reasons. As a substrate for coating, heat-treated wood has altered characteristics such as lower hygroscopicity and liquid water uptake and changed acidity, wettability, surface free energy, and anatomical microstructure. Various wood species, heat treatment method, treatment intensity, and treatment conditions exhibited a different extent of changes in wood properties. These altered properties could affect coating performance on heat-treated wood. The reported changes in acidity and in surface energy due to heat treatments are inconsistent with one another depending on wood species and temperature of the treatments. This paper gives an overview of the research results with regards to properties of heat-treated wood that can affect coating performance and weathering of uncoated and coated heat-treated wood.

show abstract

Influence of Heat Treatment on the Water Uptake Behavior of Wood

Cited by 17 publications

References 22 publications

Chemical Composition of Apricot Pit Shells and Effect of Hot-Water Extraction

Chemical Composition of Apricot Pit Shells and Effect of Hot-Water Extraction

Effect of Veneer-Drying Temperature on Selected Properties and Formaldehyde Emission of Birch Plywood

Heat-Treated Wood as a Substrate for Coatings, Weathering of Heat-Treated Wood, and Coating Performance on Heat-Treated Wood

Contact Info

Product

Resources

About