Creating water-repellent effects on wood by treatment with silanes

Holzforschung ◽  
2006 ◽  
Vol 60 (1) ◽  
pp. 40-46 ◽  
Author(s):  
Steffen Donath ◽  
Holger Militz ◽  
Carsten Mai
Keyword(s):  
Water Uptake ◽  
Treated Wood ◽  
Solid Wood ◽  
Water Repellent ◽  
Initial Water ◽  
X Ray ◽  
Ray Cells ◽  
Alkoxy Groups ◽  
Water Repellence ◽  
Water Borne

Abstract Three types of silanes were tested for their ability to impart hydrophobicity to solid wood samples: a tetraalkoxy silane bearing four hydrolysable alkoxy groups; two alkyl-trialkoxy silanes; and two multifunctional oligomeric silane systems. The first two types were applied as monomeric silane solutions and pre-condensed sols. The water uptake of treated wood was considerably reduced, especially after treatment with multifunctional water-borne silane systems, while uptake of gaseous water was not changed. Initial water repellence was most pronounced when a fluoro-alkyl functional oligomeric silane system was used; however, after a longer submersion time (24 h), the reduction in water uptake was strongly diminished. Wetting-drying cycles led to a reduction in hydrophobicity of samples treated with sols of alkoxysilanes, while aqueous functional silanes revealed enhanced water-repellent effects after these tests. This was explained by continued condensation of unreacted silanol groups in the aqueous functional silanes during the wetting-drying cycles. X-Ray mapping of silicon (SEM-EDX) showed that the reduction in water uptake due to the multifunctional silane HS 2909 is caused by plugging of the main penetration pathways such as pits, ray cells and ray tracheids.

scholarly journals Determination of decay, larvae resistance, water uptake, color, and hardness properties of wood impregnated with honeybee wax

BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 8339-8354
Author(s):  
Çağlar Akçay
Keyword(s):  
Mass Loss ◽  
Water Uptake ◽  
Larval Mortality ◽  
Surface Hardness ◽  
Treated Wood ◽  
Wood Decay ◽  
Water Repellent ◽  
Decay Fungi ◽  
Hylotrupes Bajulus ◽  
Uptake Test

The aim of the study was to determine the effect of honeybee wax impregnation on the antifungal, larvicidal, water uptake, color, and mechanical properties of wood. Wood samples (poplar, Scots pine, beech, and lime) were impregnated with melted honeybee wax under vacuum. The wax-impregnated samples were exposed to the wood-decay fungi Trametes versicolor and Neolentinus lepideus for 8 weeks. The larvicidal effect of the beeswax was tested against European old house borer (Hylotrupes bajulus L.). Water uptake, color measurements, and surface hardness were also tested. According to the obtained findings, a 34.6% mass loss was seen in the poplar control wood, and only 3.9% mass loss was found in the 100% beeswax-impregnated samples. The results showed that H. bajulus larvae could digest honeybee wax with wood when beeswax surface treatment was applied. Additionally, an average of 30% larvae mortality rate was achieved on beeswax-treated wood surfaces, compared to a 2.5% rate on the controls. However, when wood was deeply treated with beeswax, larval mortality reached 100%. In the water uptake test, beeswax-treated samples showed water repellent efficiency. The lowest water uptake (24.2%) was obtained in poplar wood treated with 100% beeswax, compared to 92.6% in the poplar control in 96 h immersion time. With the beeswax treatment, a* and b* color values increased, while the L* values decreased.

Growth of ZnO nanofilms on wood with improved photostability

Holzforschung ◽  
2010 ◽  
Vol 64 (3) ◽  
Author(s):  
Yan Yu ◽  
Zehui Jiang ◽  
Ge Wang ◽  
Ye Song
Keyword(s):  
Solution Treatment ◽  
Treated Wood ◽  
Outdoor Exposure ◽  
Solid Wood ◽  
Zno Films ◽  
Accelerated Weathering ◽  
Step Method ◽  
Major Drawback ◽  
X Ray ◽  
Nano Zinc Oxide

Abstract A major drawback of wood in outdoor exposure is photodegradation of the surface. Nano zinc oxide (ZnO) has been reported to provide enhanced stability of wood against UV degradation. In this study, the formation of ZnO nanostructures on the surface of solid wood was achieved via a simple two-step process consisting of generation of ZnO seeds on the wood surface followed by a solution treatment to promote crystal growth. The morphology and chemical composition of the ZnO films was studied by field-emission scanning electron microscopy combined with energy dispersive X-ray and X-ray diffraction. Accelerated weathering was used to evaluate the photostability of treated wood. The morphology of ZnO nanofilm was dependent on the exposure time in the ZnO seeding solution. Greatly enhanced photostability was achieved with treated wood. UV stability was partially dependent on crystal morphology. This two-step method could probably also be employed to treat other biomaterials with rough surfaces such as bamboo.

scholarly journals Comparative chemical investigations of alum treated archaeological wood from various museum collections

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Jeannette Jacqueline Łucejko ◽  
Caitlin M. A. McQueen ◽  
Malin Sahlstedt ◽  
Francesca Modugno ◽  
Maria Perla Colombini ◽  
...  
Keyword(s):  
Cultural History ◽  
Inorganic Compounds ◽  
Treated Wood ◽  
Chemical Degradation ◽  
General Level ◽  
History Museum ◽  
X Ray ◽  
Archaeological Wood ◽  
Alum Treatment ◽  
Swedish History

AbstractFrom the mid-1800s to the late 1960s, conservation by alum salts (KAl(SO4)2·12H2O—potassium aluminium sulphate), using various recipes, was a common method to prevent shrinkage and to strengthen waterlogged archaeological wooden objects. This method was mainly used in Scandinavia. The alum method appears to have also been applied to highly degraded archaeological waterlogged wood in other countries, for example in the U.S and Germany. Today, many of the archaeological wooden objects treated with alum show extreme deterioration and very low pH, which are attributed to the effects of the alum-treatment. This study investigated the extent of the current levels of chemical degradation in wooden objects conserved with alum salts at different points in time (1880s, 1930s and 1905–13) in order to understand their current condition and whether extent of degradation was in any way related to time of treatment, in an attempt to understand the rate of degradation. It was also an opportunity to compare the chemical state of preservation of alum-treated wood from different collections, as only the Oseberg collection has been intensively studied in this way up until now. Samples from historical wooden objects from the following collections were investigated and compared: the Dejbjerg collection (National Museum of Denmark in Copenhagen); the Oseberg collection (Museum of Cultural History, Oslo, Norway); the Glimmingehus collection (Swedish History Museum, Sweden). Analyses of lignocellulosic polymers and of inorganic compounds were undertaken to evaluate the chemical preservation of the wooden objects. The investigations were performed using a multi-analytical approach which consisted of: pH measurements, analytical pyrolysis (Py-GC/MS), X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDS). It was possible to link the extent of degradation with time, on a general level but we found a great variability in the state of preservation of the wood also within the same collection. It is clear, however that alum-treated wood is more degraded than archaeological wood not treated with alum.

scholarly journals Effects of Initial Water Content on Microstructure and Mechanical Properties of Lean Clay Soil Stabilized by Compound Calcium-Based Stabilizer

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1933 ◽  
Author(s):  
Chenglong Yin ◽  
Wei Zhang ◽  
Xunli Jiang ◽  
Zhiyi Huang
Keyword(s):  
Water Content ◽  
Soil Stabilization ◽  
Clay Soil ◽  
Soil Aggregates ◽  
Optical Microscope ◽  
Initial Water Content ◽  
Reaction Products ◽  
Unconfined Compression Test ◽  
Initial Water ◽  
X Ray

Initial water content significantly affects the efficiency of soil stabilization. In this study, the effects of initial water content on the compressibility, strength, microstructure, and composition of a lean clay soil stabilized by compound calcium-based stabilizer were investigated by static compaction test, unconfined compression test, optical microscope observations, environment scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The results indicate that as the initial water content increases in the range studied, both the compaction energy and the maximum compaction force decrease linearly and there are less soil aggregates or agglomerations, and a smaller proportion of large pores in the compacted mixture structure. In addition, for specimens cured with or without external water supply and under different compaction degrees, the variation law of the unconfined compressive strength with initial water content is different and the highest strength value is obtained at various initial water contents. With the increase of initial water content, the percentage of the oxygen element tends to increase in the reaction products of the calcium-based stabilizer, whereas the primary mineral composition of the soil-stabilizer mixture did not change notably.

Characterization of interfacial stress transfer ability in acetylation-treated wood fibre composites using X-ray microtomography

2017 ◽  
Vol 95 ◽  
pp. 43-49 ◽  
Author(s):  
Thomas Joffre ◽  
Kristoffer Segerholm ◽  
Cecilia Persson ◽  
Stig L. Bardage ◽  
Cris L. Luengo Hendriks ◽  
...  
Keyword(s):  
Treated Wood ◽  
Stress Transfer ◽  
Wood Fibre ◽  
Interfacial Stress ◽  
X Ray ◽  
Fibre Composites

Structure-Property Relationship of Castor Oil Based Chain Extended Polyurethane/Starch Biocomposites

2010 ◽  
Vol 123-125 ◽  
pp. 371-374
Author(s):  
Siddaramaiah ◽  
Manjula Koregala Sidde Gowda ◽  
Joong Hee Lee
Keyword(s):  
Mechanical Properties ◽  
Water Uptake ◽  
Castor Oil ◽  
Structure Property ◽  
X Ray ◽  
Property Relationship ◽  
Structure Property Relationship ◽  
Relationship Of

Polyurethane (PU)/starch biocomposites have been prepared with different weight fractions of starch (viz., from 0 to 40 wt %). The fabricated PU/starch composites were characterized by mechanical properties and thermal (DSC and TGA) behaviors. Microcrystalline parameters were calculated using X-ray profile. Water uptake and its effect on mechanical properties have been evaluated.

scholarly journals Lotus-Inspired Multiscale Superhydrophobic AA5083 Resisting Surface Contamination and Marine Corrosion Attack

Materials ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1592 ◽  
Author(s):  
Binbin Zhang ◽  
Weichen Xu ◽  
Qingjun Zhu ◽  
Shuai Yuan ◽  
Yantao Li
Keyword(s):  
Photoelectron Spectroscopy ◽  
Chemical Elements ◽  
Surface Contamination ◽  
Localized Corrosion ◽  
Metallic Surface ◽  
Water Repellent ◽  
Corrosion Attack ◽  
X Ray ◽  
Self Cleaning

The massive and long-term service of 5083 aluminum alloy (AA5083) is restricted by several shortcomings in marine and industrial environments, such as proneness to localized corrosion attack, surface contamination, etc. Herein, we report a facile and cost-effective strategy to transform intrinsic hydrophilicity into water-repellent superhydrophobicity, combining fluorine-free chemisorption of a hydrophobic agent with etching texture. Dual-scale hierarchical structure, surface height relief and surface chemical elements were studied by field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), successively. Detailed investigations of the wetting property, self-cleaning effect, NaCl-particle self-propelling, corrosion and long-term behavior of the consequent superhydrophobic AA5083 surface were carried out, demonstrating extremely low adhesivity and outstanding water-repellent, self-cleaning and corrosion-resisting performance with long-term stability. We believe that the low cost, scalable and fluorine-free transforming of metallic surface wettability into waterproof superhydrophobicity is a possible strategy towards anti-contamination and marine anti-corrosion.

scholarly journals Effects of Shellac Treatment on Wood Hygroscopicity, Dimensional Stability and Thermostability

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 881
Author(s):  
Mihaela Liu ◽  
Guanglin Xu ◽  
Jianan Wang ◽  
Xinwei Tu ◽  
Xinyou Liu ◽  
...  
Keyword(s):  
Dimensional Stability ◽  
Moisture Absorption ◽  
Morphological Characteristics ◽  
Treated Wood ◽  
Wood Products ◽  
Control Group ◽  
Water Repellent ◽  
Thermoplastic Resin ◽  
Weight Percentage ◽  
Thermogravimetric Curve

Dimensional stability proves to be an important factor affecting the quality of wooden products. As a sort of crude and thermoplastic resin, shellac excreted by lac insects demonstrates water-repellent and environmental-friendly features. The research impregnated shellac with wood at room temperature and with a vacuum-pressure procedure. Efforts were made to examine how shellac treatment affected the dimensional stability, moisture absorption, chemical structure, thermostability, as well as morphological characteristics of wood. Results indicated that shellac treatment was a type of efficient solution useful in the enhancement of the dimensional stability of wood. Shellac solution had good permeability in the wood, and the weight percentage gain reached 13.01% after impregnation. The swelling coefficients of treated wood in the tangential and radial directions decreased by 20.13% and 24.12%, respectively, indicating that impregnation could improve wood dimensional stability. The moisture absorption of shellac-treated wood was reduced by 38.15% under 20 °C and 65% relative humidity. Moreover, shellac treatment significantly modified wood structure, although there were no drastic changes in the spectra. Specimens for shellac treatment ran across two decomposition peaks at 350 and 390 °C, and specimens in the control group saw one more common derivative thermogravimetric curve when the sharp peak approached 355 °C. After impregnation of shellac into wood, the shellac blocked pits and hardened on the intrinsic layer of the wood for fear of hygroscopicity. The practice was applicable to a variety of wood products, such as buildings, furniture, and landscape architecture.

Water repellence in sandy soils of South-Western Australia. II. Some chemical characteristics of the hydrophobic skins

Soil Research ◽  
1972 ◽  
Vol 10 (1) ◽  
pp. 35 ◽  
Author(s):  
FJ Roberts ◽  
BA Carbon
Keyword(s):  
Organic Matter ◽  
Diethyl Ether ◽  
Cold Water ◽  
Sandy Soils ◽  
Prolonged Treatment ◽  
Water Repellent ◽  
Chemical Characteristics ◽  
Produce Water ◽  
Water Repellence ◽  
Humic Fraction

The hydrophobic organic skins on sand grains were resistant to removal by solvents such as cold water, concentrated acid, diethyl ether, ethanol, benzene, chloroform, and acetone. Prolonged treatment with hot diethyl ether, ethanol, and benzene removed part of the coating. Treatment with dilute solutions of alkali removed the skin as suspended particles. Compounds within the very stable humic fraction of the soil organic matter appeared to be mainly responsible for water repellence in soils. Deposits of fresh organic materials could also produce water repellent properties.

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