scholarly journals Decay resistance of acetylated and hexanoylated hardwood and softwood species exposed to Coniophora puteana

Holzforschung ◽  
2009 ◽  
Vol 63 (5) ◽  
Author(s):  
Callum A.S. Hill ◽  
Simon F. Curling ◽  
Jin H. Kwon ◽  
Virginie Marty
Keyword(s):  
Chemical Modification ◽  
Brown Rot ◽  
European Beech ◽  
Decay Resistance ◽  
Pinus Koraiensis ◽  
Larix Kaempferi ◽  
White Oak ◽  
Weight Percentage ◽  
Coniophora Puteana ◽  
Main Factors

Abstract The effect of chemical modification with acetic or hexanoic anhydride upon the decay resistance of wood was studied. Both sapwoods and heartwoods of the following trees were investigated: Japanese larch, Larix kaempferi (Lamb.) Carrière; Korean pine, Pinus koraiensis Siebold et Zucc. as softwoods and European beech (only sapwood), Fagus sylvatica L.; oriental white oak, Quercus aliena (Blume) as hardwoods. After chemical modification, the samples were exposed to the brown rot fungus Coniophora puteana (FPRL 11E). The study investigated whether weight percentage gain or degree of hydroxyl substitution were the main factors controlling decay resistance. It was found that decay resistance is associated primarily with cell wall bulking rather than hydroxyl substitution. However, there are differences in behaviour between the acetylated and hexanoylated wood and the possible reasons for these differences are discussed.

Decay resistance of anhydride-modified Corsican pine sapwood exposed to the brown rot fungus Coniophora puteana

Holzforschung ◽  
2006 ◽  
Vol 60 (6) ◽  
pp. 625-629 ◽  
Author(s):  
Callum A.S. Hill ◽  
Michael D. Hale ◽  
Graham A. Ormondroyd ◽  
Jin H. Kwon ◽  
Simon C. Forster
Keyword(s):  
Brown Rot ◽  
Pinus Nigra ◽  
Decay Resistance ◽  
Exposure Test ◽  
Weight Percentage ◽  
Coniophora Puteana ◽  
Chemically Modified ◽  
Brown Rot Fungus ◽  
The Relationship ◽  
Modified Wood

Abstract Corsican pine (Pinus nigra) sapwood was chemically modified with acetic or hexanoic anhydride to a variety of weight gains. The modified wood was exposed to the brown rot fungus Coniophora puteana, and the relationship between weight loss due to decay and weight percentage gain, or degree of hydroxyl substitution, was determined in a 16-week exposure test. The effect of exposure time and the strain of C. puteana upon the decay protection threshold of acetylated Corsican pine was also examined.

scholarly journals Decay Resistance of Acetic, Propionic, and Butyric Anhydrides Modified Rubberwood Against Brown Rot (Coniophora puteana)

BioResources ◽  
2017 ◽  
Vol 12 (3) ◽  
Author(s):  
Nuraishah Hassan ◽  
Norul Hisham Hamid ◽  
Mohammad Jawaid ◽  
Paridah Md. Tahir ◽  
Salmiah Ujang
Keyword(s):  
Brown Rot ◽  
Decay Resistance ◽  
Coniophora Puteana

scholarly journals DECAY RESISTANCE, DIMENSIONAL STABILITY AND MECHANICAL STRENGTH OF POPLAR WOOD MODIFIED WITH PLANT-DERIVED COMPOUNDS

Wood Research ◽  
2021 ◽  
Vol 66 (4) ◽  
pp. 556-568
Author(s):  
JIAPENG WANG ◽  
ZHENJU BI ◽  
ZHANGJING CHEN ◽  
LI YAN ◽  
YAFANG LEI
Keyword(s):  
Mechanical Properties ◽  
Citric Acid ◽  
Dimensional Stability ◽  
Color Change ◽  
White Rot Fungi ◽  
Brown Rot ◽  
Decay Resistance ◽  
White Rot ◽  
Modulus Of Rupture ◽  
Weight Percentage

The cinnamaldehyde, salicylic acid, stearolic acid and citric acid were plant-derived organic compounds that can be activated to fungi, that could degrade the wood in long term. The compounds with concentrations of 3%, 5% and 7% assisted by different dispersants were impregnated into poplar (Populus nigra L.) specimens by the vacuum-pressure method. After that, weight percentage gain (WPG), decay resistance against white-rot fungi (Trametes versicolor) and brown-rot fungi (Gloeophyllum trabeum), color change, dimensional stability and mechanical properties including modulus of elasticity (MOE) and modulus of rupture (MOR) were measured. The results indicated that cinnamaldehyde impregnated poplar showed antifungi activity against both G. trabeumand T. versicolor, and citric acid impregnated poplar showed antifungi activity against G. trabeum. The color of poplar specimens before and after impregnated cinnamaldehyde and citric acid had a little change, dimensional stability had been improved and mechanical properties especially for MOR increased significantly.

scholarly journals Small Angle Neutron Scattering Reveals Wood Nanostructural Features in Decay Resistant Chemically Modified Wood

2022 ◽  
Vol 4 ◽  
Author(s):  
Rebecca E. Ibach ◽  
Nayomi Z. Plaza ◽  
Sai Venkatesh Pingali
Keyword(s):  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Water Distribution ◽  
Deuterium Oxide ◽  
Brown Rot ◽  
Decay Resistance ◽  
Weight Percentage ◽  
Chemically Modified ◽  
Alkylene Oxide

While it is known that modifying the hydroxyls in wood can improve the decay resistance; what is often missing in the literature is whether these modifications alter wood nanostructure, and how these changes correlate to the improved decay resistance. Here, we used small angle neutron scattering (SANS) to probe the effects of alkylene oxide modifications on wood nanostructure. Southern pine wood samples were chemically modified to various weight percentage gains (WPG) using four different alkylene oxides: propylene oxide (PO), butylene oxide (BO), epichlorohydrin (EpH), and epoxybutene (EpB). After modification, the samples were water leached for 2 weeks to remove any unreacted reagents or homopolymers and then equilibrium moisture content (EMC) was determined at 90% relative humidity (RH) and 27°C. Laboratory soil block decay evaluations against the brown rot fungus Gloeophyllum trabeum were performed to determine weight loss and biological efficacy of the modifications. To assist in understanding the mechanism, SANS was used to study samples that were fully immersed in deuterium oxide (D2O). These measurements revealed that the modifications altered the water distribution inside the cell wall, and the most effective modifications reduced the microfibril swelling and preserved the microfibril structure even after being subject to 12 weeks of brown rot exposure.

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

Holzforschung ◽  
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.

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.

A study of natural durability of selected coniferous wood species from north Asia affected by the fungus Coniophora puteana (Schumach.) P. Karst.

2020 ◽  
Vol 112 ◽  
pp. 32-35
Author(s):  
Boguslaw Andres ◽  
Agnieszka Jankowska ◽  
Grzegorz Duchnik
Keyword(s):  
Wood Species ◽  
Brown Rot ◽  
Larix Sibirica ◽  
Natural Durability ◽  
Pinus Sibirica ◽  
European Larch ◽  
Coniophora Puteana ◽  
North Asia ◽  
Coniferous Wood ◽  
Pinus Sibirica Du Tour

The aim of prestened study was to determine the natural durability of selected coniferous wood species from Asia to the effect of Coniophora puteana (Schumach.) P. Karst., which causes brown rot. The species tested were: Larix gmellini (Rupr.) Kuzen., Larix sibirica Ledeb. and Pinus sibirica Du Tour.. The test was conducted on the basis of PN-EN 350:2016-10 and PN-EN 113:2000. As a result of the research durability classes were determined. Wood durability of tested Asian species was compared with the domestic wood species such as Pinus sylvestris L. and Larix decidua Mill.. The most durable of the tested wood species was Larix sibirica Ledeb., while the European larch showed comparable durability. The wood of Larix gmellini (Rupr.) Kuzen. showed the lowest persistence among the tested species.

scholarly journals The Impact of Paraffin-Thermal Modification of Beech Wood on Its Biological, Physical and Mechanical Properties

Forests ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1102 ◽  
Author(s):  
Ladislav Reinprecht ◽  
Miroslav Repák
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Beech Wood ◽  
Physical And Mechanical Properties ◽  
Brown Rot ◽  
European Beech ◽  
White Rot ◽  
White Rot Fungus ◽  
Poria Placenta ◽  
The Impact

The European beech (Fagus sylvatica L.) wood was thermally modified in the presence of paraffin at the temperatures of 190 or 210 °C for 1, 2, 3 or 4 h. A significant increase in its resistance to the brown-rot fungus Poria placenta (by 71.4%–98.4%) and the white-rot fungus Trametes versicolor (by 50.1%–99.5%) was observed as a result of all modification modes. However, an increase in the resistance of beech wood surfaces to the mold Aspergillus niger was achieved only under more severe modification regimes taking 4 h at 190 or 210 °C. Water resistance of paraffin-thermally modified beech wood improved—soaking reduced by 30.2%–35.8% and volume swelling by 26.8%–62.9% after 336 h of exposure in water. On the contrary, its mechanical properties worsened—impact bending strength decreased by 17.8%–48.3% and Brinell hardness by 2.4%–63.9%.

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