scholarly journals The Biological Durability of Thermally- and Chemically-Modified Black Pine and Poplar Wood Against Basidiomycetes and Mold Action

Forests ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1111 ◽  
Author(s):  
Vasiliki Kamperidou
Keyword(s):  
Treated Wood ◽  
Thermal Modification ◽  
Black Pine ◽  
Poplar Wood ◽  
Lower Mass ◽  
Pine Wood ◽  
Mass Losses ◽  
Biological Durability ◽  
Unmodified Wood ◽  
Thermally Treated

Wood of black pine and poplar species were subjected to thermal modification under variant conditions, while subsequently, a number of the thermally-modified black pine specimens were subjected to surface modification with organosilane solutions, and the biological resistances of the different materials were examined using laboratory agar block tests against the action of basidiomycetes and microfungi. Thermally-modified pine specimens were exposed to the brown rot fungi Coniophora puteana and Oligoporus placenta, whereas poplar wood was exposed to the white rot fungus Trametes versicolor and O. placenta. Regarding the biological durability of thermally-chemically-treated pine wood with organosilanes, it was tested against the action of C. puteana. Additionally, both of the thermally-treated wood species, as well as thermally-chemically-treated pine wood were exposed to a microfungi mixture, so that the wood treatments efficacy would be evaluated through a visual assessment of fungal growth on the specimen’s surface The thermal treatments seem to increase the biological resistance of black pine against C. puteana by 9.65–36.73% compared to unmodified wood. The most significant increase in biological durability among all the thermally-treated wood categories was recorded by O. placenta, with 28.75–68.46% lower mass losses in treated pine specimens and 31.98–64.72% in thermally-treated poplar, respectively, compared to unmodified wood. The resistance of treated poplar against T. versicolor was also found increased (13.25–46.08%), compared to control. Thermal modification affected positively the biological resistance of both species, though it did not manage to protect effectively pine and poplar wood from the microfungi action. The combination of thermal and organosilanes treatment revealed a significant improvement of the durability of pine wood compared to? control (45.68–87.83% lower mass losses against C. puteana), as well as against the microfungi action, with the presence of benzin to have a positive effect on the silanes solutions performance and protective action.

Innovative Alkyd Emulsion Composition Enhanced With Nanosize Iron Oxides for the Protection of Thermally Treated Wood in Outdoor Conditions

2021 ◽  
Author(s):  
◽  
Errj Sansonetti
Keyword(s):  
Iron Oxide ◽  
Surface Energy ◽  
Wood Surface ◽  
Treated Wood ◽  
Thermal Modification ◽  
Alkyd Emulsion ◽  
Water Based ◽  
Outdoor Weathering ◽  
Iron Oxide Pigments ◽  
Thermally Treated

Wood has great potential for uses in outdoor conditions, but it can be easily degraded due to the action of environmental factors (solar radiation, moisture, fungi, insects, etc.). The protection of wood is therefore a very actual research topic, and it is also the object of this work. The main goal of this Doctoral Thesis is to obtain a water-based alkyd paint formulation in the form of emulsion and to optimize its composition with necessary additives, in particular, with nanosized red iron oxide pigments which can protect the decorative qualities of thermally treated wood (TTW) during outdoor exposure. In the literature review, the main factors responsible for the degradation of wood and their effect on the structure and properties of wood are summarized. The chemistry of coatings for the protection of wood and the challenges that are faced in reformulation of paints, due to more stringent regulations which limit the use of organic solvents and promote greener alternatives, like water-based paint formulations, are considered. In Europe, this is stated by the Directive 2004/42/EC of the European Parliament on the limitation of emissions of volatile organic compounds (VOC) from decorative paints and varnishes. In the first part of the experimental section, the optimal composition of the alkyd emulsion and the effects of additives on the film properties have been investigated. The different chemo-physical properties of thermally treated wood compared with those of untreated wood have been also evaluated. After thermal modification, wood becomes more hydrophobic and this has been confirmed from the changes of the surface energy of thermally treated wood: the polar component of the surface energy decreases with increasing temperature of thermal modification. In the second part of the experimental section, artificial and outdoor weathering tests have been done to determine the suitable concentration of red iron oxide nanoparticles which can give better protection against photodegradation. Results show that red iron oxide pigments at a concentration of 8 % in alkyd emulsion are efficient to protect the wood surface against discoloration. During the outdoor weathering test, the performance of alkyd emulsion has been compared with that of the solvent-based formulation. Results confirm that the water-based alkyd emulsion gives better protection of the thermally treated wood surface than the solvent-based formulation, thus confirming that the replacement of organic solvent with water gives a product with equivalent or better properties for the protection of thermally treated wood in outdoor conditions.

scholarly journals Chemical and Structural Characterization of Poplar and Black Pine Wood Exposed to Short Thermal Modification

2021 ◽  
Vol 72 (2) ◽  
pp. 155-167
Author(s):  
Vasiliki Kamperidou
Keyword(s):  
Raw Materials ◽  
Solid Wood ◽  
Thermal Modification ◽  
Moisture Loss ◽  
Black Pine ◽  
Pine Wood ◽  
Application Range ◽  
Ft Ir ◽  
And Performance ◽  
Wood Based Composite

In this study, poplar and black pine wood was exposed to short thermal treatments, aiming to improve some crucial properties. Using wet chemical analyses and Fourier-transform infrared spectroscopy (FT-IR), the influence of these treatments on the chemical composition of the modified species was investigated, as well as on the wood structure, using scanning electron microscopy. With the increase of heat treatment intensity, a mass loss of both species was recorded, attributed to the moisture loss and degradation of volatile compounds, as well as thermally less stable components. In the first treatment stages, the extractives presented a decrease, whereas with the duration and temperature increase, new extractives were formed. Lignin increased its network through ramification, especially at 200 ºC, while holocellulose was found lower in all modified wood categories of both species than in unmodified wood due to the intense decomposition of hemicelluloses. The findings of FT-IR analyses were in line with the chemical analysis results. The thermal modification process made wood materials more hydrophobic and dimensionally stable, providing protection against decomposing factors. At the same time, they were not intensively thermo-degraded, which increased their utilization perspectives and application range as solid wood of enhanced properties, or as wood particles/fibers participating as raw materials in wood-based composite products, wood-polymers composites etc., enhancing their materials compatibility, properties and performance.

scholarly journals Heat-Treated Wood Reinforced High Density Polyethylene Composites

2021 ◽  
Vol 72 (3) ◽  
pp. 219-229
Author(s):  
Kadir Karakuş ◽  
Deniz Aydemir ◽  
Gokhan Gunduz ◽  
Fatih Mengeloğlu
Keyword(s):  
Mechanical Properties ◽  
High Density Polyethylene ◽  
Wood Flour ◽  
Tensile Modulus ◽  
Treated Wood ◽  
High Density ◽  
Black Pine ◽  
Sem Images ◽  
Pine Wood ◽  
Heat Treated

This study investigated the effect of untreated and heat-treated ash and black pine wood flour concentrations on the selected properties of high density polyethylene (HDPE) composites. HDPE and wood flour were used as thermoplastic matrix and filler, respectively. The blends of HDPE and wood fl our were compounded using single screw extruder and test samples were prepared through injection molding. Mechanical properties like tensile strength (TS), tensile modulus (TM), elongation at break (EatB), fl exural strength (FS), fl exural modulus (FM) and impact strength (IS) of manufactured composites were determined. Wood fl our concentrations have significantly increased density, FS, TM and FM and hardness of composites while reducing TS, EatB and IS. Heat-treated ash and black pine fl our reinforced HDPE composites had higher mechanical properties than untreated ones. Composites showed two main decomposition peaks; one coming from ash wood flour (353-370 °C) and black pine wood fl our (373-376 °C), the second one from HDPE degradation (469-490 °C). SEM images showed improved dispersion of heat-treated ash and black pine wood flour. The obtained results showed that both the untreated and heat-treated ash/black pine wood flour have an important potential in the manufacture of HDPE composites.

In-situ catalytic co-pyrolysis of kukersite oil shale with black pine wood over acid zeolites

2021 ◽  
Vol 155 ◽  
pp. 105050
Author(s):  
Young-Kwon Park ◽  
Muhammad Zain Siddiqui ◽  
Selhan Karagöz ◽  
Tae Uk Han ◽  
Atsushi Watanabe ◽  
...  
Keyword(s):  
Oil Shale ◽  
Black Pine ◽  
Pine Wood ◽  
Acid Zeolites

A review on life cycle assessments of thermally modified wood

Holzforschung ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Kévin Candelier ◽  
Janka Dibdiakova
Keyword(s):  
Life Cycle ◽  
Environmental Impacts ◽  
Treated Wood ◽  
Single Step ◽  
Thermal Modification ◽  
Wood Products ◽  
Wood Preservation ◽  
Cumulative Energy ◽  
Thermally Modified Wood ◽  
Cumulative Energy Intake

AbstractThis review compiles various literature studies on the environmental impacts associated with the processes of thermal modification of wood. In wood preservation field, the wood modification by heat is considered as an ecofriendly process due to the absence of any additional chemicals. However, it is challenging to find proper scientific and industrial data that support this aspect. There are still very few complete studies on the life cycle assessment (LCA) and even less studies on the environmental impacts related to wood heat treatment processes whether on a laboratory or on an industrial scales. This comprehensive review on environmental impact assessment emphasizes environmental categories such as dwindling of natural resources, cumulative energy intake, gaseous, solid and liquid emissions occurred by the thermal-treated wood industry. All literature-based data were collected for every single step of the process of wood thermal modification like resources, treatment process, transport and distribution, uses and end of life of treated wood products.

A thermal modification technique combining bulk densification and heat treatment for poplar wood with low moisture content

2021 ◽  
Vol 291 ◽  
pp. 123395
Author(s):  
Xianju Wang ◽  
Dengyun Tu ◽  
Chuanfu Chen ◽  
Qiaofang Zhou ◽  
Huixian Huang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Moisture Content ◽  
Thermal Modification ◽  
Poplar Wood ◽  
Modification Technique

scholarly journals Bacterial Biodegradation of Extractives and Patterns of Bordered Pit Membrane Attack in Pine Wood

2000 ◽  
Vol 66 (12) ◽  
pp. 5201-5205 ◽  
Author(s):  
Todd A. Burnes ◽  
Robert A. Blanchette ◽  
Roberta L. Farrell
Keyword(s):  
Xanthomonas Campestris ◽  
Treated Wood ◽  
Wood Chips ◽  
Pulp Mills ◽  
Wood Extractives ◽  
Bordered Pit ◽  
Pine Wood ◽  
Pit Membrane ◽  
Pine Wood Chips ◽  
Ray Parenchyma Cells

ABSTRACT Wood extractives, commonly referred to as pitch, cause major problems in the manufacturing of pulp and paper. Treatment of nonsterile southern yellow pine chips for 14 days withPseudomonas fluorescens, Pseudomonas sp.,Xanthomonas campestris, and Serratia marcescens reduced wood extractives by as much as 40%. Control treatments receiving only water lost 11% of extractives due to the growth of naturally occurring microorganisms. Control treatments were visually discolored after the 14-day incubation, whereas bacterium-treated wood chips were free of dark staining. Investigations using P. fluorescens NRRL B21432 showed that all individual resin and fatty acid components of the pine wood extractives were substantially reduced. Micromorphological observations showed that bacteria were able to colonize resin canals, ray parenchyma cells, and tracheids. Tracheid pit membranes within bordered pit chambers were degraded after treatment with P. fluorescensNRRL B21432. P. fluorescens and the other bacteria tested appear to have the potential for biological processing to substantially reduce wood extractives in pine wood chips prior to the paper making process so that problems associated with pitch in pulp mills can be controlled.

Dimensional Stability of Poplar Wood after Densification Combined with Heat Treatment

2012 ◽  
Vol 152-154 ◽  
pp. 112-116 ◽  
Author(s):  
Jia Bin Cai ◽  
Tao Ding ◽  
Liu Yang
Keyword(s):  
Heat Treatment ◽  
Dimensional Stability ◽  
Hybrid Poplar ◽  
Treatment Temperature ◽  
Thermal Modification ◽  
Holding Time ◽  
Poplar Wood ◽  
Compression Set ◽  
Densification Temperature

Hybrid poplar boards were subjected to thermo-mechanical densification combined with heat treatment. Hydroscopicity and hygroscopicity of the treated samples were measured. The results showed that dimensional stability of the samples was influenced by compression set significantly. The higher the compression set, the greater the swelling of the samples. On the contrary, the influence of densification temperature and duration was not significant. Thermal modification significantly reduced hydroscopicity and hygroscopicity of the samples. Both higher treatment temperature and longer holding time resulted in better dimensional stability.

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