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 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.

scholarly journals A Multi-Technique Approach to Evaluate the Surface Properties of Heat-Treated Chestnut Wood Finished with a Water-Based Coating

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 706
Author(s):  
Claudia Pelosi ◽  
Gianluca Rubino ◽  
Giuseppe Capobianco ◽  
Luca Lanteri ◽  
Giorgia Agresti ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Surface Properties ◽  
Central Italy ◽  
Colour Change ◽  
Treated Wood ◽  
Castanea Sativa ◽  
Heat Treated ◽  
Water Based ◽  
Chestnut Wood ◽  
Thermally Treated

The aim of the present work is to investigate the surface properties and the effect of a water-based coating on chestnut wood (Castanea sativa Mill.), both untreated and thermally treated. Chestnut is very common throughout the Mediterranean region and its wood is widely used as timber, especially in Central Italy, to build window fixtures and doors which have to be decay-resistant, even in historical buildings. Traditional techniques have been used in combination with Hyperspectral Imaging which had never been used before to examine thermally treated wood. Specifically, colour, roughness, micro-hardness, wear and contact angle measurements have been performed on untreated and thermally treated chestnut wood, covered by a commercial water-based coating named Idrolinfo. Hyperspectral analysis has been demonstrated to be appropriate to discriminate the heat treatment and the presence of the water-based product. The applied techniques showed that the best performances are obtained with the 170 °C heat treatment. The water-based coating demonstrated its validity when applied to untreated and heat-treated wood at 140 °C and 170 °C. The main findings showed that chestnut wood increased or maintained its properties if treated at those temperatures without undergoing a major colour change, acquiring good hydrophobicity, both if uncoated or treated with the water-based coating.

Iron oxide pigments

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Gerhard Pfaff
Keyword(s):  
Iron Oxide ◽  
Solid State ◽  
Large Scale ◽  
Construction Materials ◽  
High Importance ◽  
Precipitation Processes ◽  
Iron Oxide Pigments ◽  
Natural And Synthetic

AbstractNatural and synthetic iron oxide pigments are by far the most important colored pigments. Their high importance is based on the variety of stable colors ranging from yellow via orange, red and brown to black. Iron oxide yellow (α-FeOOH), iron oxide red (α-Fe2O3) and iron oxide black (Fe3O4) are the most important representatives of the iron oxide pigments. Synthetic iron oxide pigments are produced industrially on a large scale by solid-state processes, precipitation processes and by the Laux process. Main advantages of synthetic iron oxide pigments compared with natural types are their pure hue, the consistent, reproducible quality and their tinting strength. Iron oxide pigments are mainly used in construction materials, paints, coatings, and plastics, but also in cosmetics, pharmaceuticals and special applications such as ceramics, magnetic coatings and toners.

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.

scholarly journals Heterogeneity of population of microorganisms grown in presence of iron oxide maghemite nanoparticles

2018 ◽  
Vol 185 ◽  
pp. 10002 ◽  
Author(s):  
Tatyana P. Denisova ◽  
Elena V. Simonova ◽  
Lubov A. Kokorina ◽  
Evgenia N. Maximova ◽  
Oleg M. Samatov ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Intercellular Communication ◽  
Maghemite Nanoparticles ◽  
Cultivation Temperature ◽  
Large White ◽  
Laser Target ◽  
Water Based

In this work γ-Fe2O3 MNPs were obtained by laser target evaporation and water based suspensions were prepared. Maximum permissive dose of iron in water (MPD) is 0.3 mg/L. It was found that 100 MPD dose of iron induces formation of non-typical colonies after 72 or 96 hours exposition: against a background of small black colonies large white colonies appeared due to a disruption in tyrosine synthesis. Multiple re-cloning of the white colonies grown with MNPs showed that they retained their properties both under standard conditions (temperature of 24 °C) and at the temperatures up to 37o C. E.nigrum grown with MNPs demonstrated very scant extension of small colonies at the cultivation temperature of 24o C, their growth was completely blocked at 37°C. Significant changes in the structure of the population were noted. First of all, large cells with pronounced aggregation were observed among the black colonies. These aggregates consisted of large cells connected to each other by matrix. In the white colonies the appearance of very long threadlike cells connecting different groups of the cells establishing an intercellular communication was evident. Fe2O3 MNPs induce an increase in the heterogeneity of the population, expressed as a change in morpho-physiological states.

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