scholarly journals THE PROSPECT OF USING A-VINYLNAPHTHALENE FOR MODIFICATION OF WOOD MATERIALS

2021 ◽  
Vol 6 (2) ◽  
pp. 73-79
Author(s):  
N. Nikulina ◽  
A. Dmitrenkov ◽  
S. Nikulin ◽  
L. Vlasova ◽  
N. Sannikova
Keyword(s):  
Elevated Temperatures ◽  
External Factors ◽  
Radical Mechanism ◽  
Birch Wood ◽  
Natural Polymer ◽  
Wood Polymer ◽  
Natural Wood ◽  
Protective Treatment ◽  
Composite Samples ◽  
Modified Wood

Natural wood is the most common natural polymer material that is affordable, non-toxic and widely used in various fields of industry and construction. However, wood also has disadvantages, to eliminate which it is modified with the use of organic and inorganic agents, oligomers and polymers that can protect it from external factors. The paper studies the possibility of using such a vinylaromatic monomer as α-vinylnaphthalene for modification and protective treatment of natural birch wood. It is shown that during processing in the conductive elements of birch wood under the influence of elevated temperatures, the polymerization of α-vinyl naphthalene proceeds by a radical mechanism. However, 100 % conversion of α-vinylnaphthalene and polyvinylnaphthalene cannot be achieved. Thus, the conductive elements of natural wood contain a composite consisting of α-vinyl naphthalene and polyvinyl naphthalene. It is shown that with an increase in the content of the proposed modifier in birch wood, water absorption and swelling of wood-polymer-monomer composite samples significantly decreases. This will increase the service life of products based on modified wood. The introduction of the proposed technology for modifying low-value wood species will contribute to the conservation of forest resources and their rational use

scholarly journals RESEARCH OF THE PROCESS OF BIRCH WOOD IMPREGNATION WITH THE USED VEGETABLE OIL

2020 ◽  
Vol 10 (2) ◽  
pp. 161-168
Author(s):  
Aleksandr Dmitrenkov ◽  
Alexander Vostrikov ◽  
Nadezhda Nikulina ◽  
Aleksandr Borovskoy ◽  
Ekaterina Nedzel'skaya
Keyword(s):  
Heat Treatment ◽  
Vegetable Oil ◽  
Sunflower Oil ◽  
Latin Square ◽  
Regression Equations ◽  
Birch Wood ◽  
Wood Impregnation ◽  
Natural Wood ◽  
Impregnation Temperature ◽  
Modified Wood

Wood is widely used in various industries. However, the inherent ability of natural wood to absorb water and other disadvantages require its modification with various compositions. In the work, the technology of impregnation of birch wood with processed vegetable oil, which remains after cooking, has been studied. Impregnated composition was introduced into pre-prepared wood using the “hot-cold baths” method and subsequent heat treatment of wood impregnated with used sunflower oil. The influence of the main quantitative parameters of the impregnation process on the performance of wood specimens have been made using the design of the experiment according to the Greek-Latin square pattern of the fourth order. The influence of the temperature of the impregnating oil, the time of impregnation, temperature and the duration of the heat treatment on the properties of modified wood has been studied. The properties of birch wood has been evaluated by its water absorption, as well as swelling of specimens in the radial and tangential directions. The regression equations have been obtained. They describe the influence of the main parameters of the impregnatio process with processed sunflower oil on the properties of modified wood. The best conditions for introducing processed sunflower oil into wood have been established. The proposed impregnating composition improves decorative properties of wood. It is odorless and environmentally friendly. It has been shown that treating birch wood with processed vegetable oil makes it possible to obtain modified wood with increased resistance to water

Long-Term Durability of Modified Wood-Polymer Composite to Alternate the Solid Wood External Application

2015 ◽  
Vol 1122 ◽  
pp. 165-168
Author(s):  
Anna Benešová ◽  
Jan Vanerek
Keyword(s):  
Polymer Composite ◽  
Solid Wood ◽  
External Application ◽  
Wood Polymer ◽  
External Conditions ◽  
Temperature Action ◽  
Wood Polymer Composite ◽  
Composite Samples ◽  
Modified Wood

The contribution deals with the durability of modified wood-polymer composite samples intended to alternate solid wood non-bearing structures (fences, sidings). The modification was made to the polymer matrix, which is partly consisting of commercially available regranulate. Four types of composite with varying amount of regranulate admixture are exposed to adverse ambience simulating the external conditions through moisture, freeze and high temperature action. The aim of the research is to determine the influence of regranulate share on the visual and mechanical characteristic of the material, which would be decisive in the process of specific tile creation.

scholarly journals Review of Functional Treatments for Modified Wood

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 327
Author(s):  
Morwenna J. Spear ◽  
Simon F. Curling ◽  
Athanasios Dimitriou ◽  
Graham A. Ormondroyd
Keyword(s):  
High Performance ◽  
Responsive Materials ◽  
Wood Modification ◽  
Wide Range ◽  
Natural Wood ◽  
Impregnation Modification ◽  
New Applications ◽  
New Generation ◽  
Dimensional Instability ◽  
Modified Wood

Wood modification is now widely recognized as offering enhanced properties of wood and overcoming issues such as dimensional instability and biodegradability which affect natural wood. Typical wood modification systems use chemical modification, impregnation modification or thermal modification, and these vary in the properties achieved. As control and understanding of the wood modification systems has progressed, further opportunities have arisen to add extra functionalities to the modified wood. These include UV stabilisation, fire retardancy, or enhanced suitability for paints and coatings. Thus, wood may become a multi-functional material through a series of modifications, treatments or reactions, to create a high-performance material with previously impossible properties. In this paper we review systems that combine the well-established wood modification procedures with secondary techniques or modifications to deliver emerging technologies with multi-functionality. The new applications targeted using this additional functionality are diverse and range from increased electrical conductivity, creation of sensors or responsive materials, improvement of wellbeing in the built environment, and enhanced fire and flame protection. We identified two parallel and connected themes: (1) the functionalisation of modified timber and (2) the modification of timber to provide (multi)-functionality. A wide range of nanotechnology concepts have been harnessed by this new generation of wood modifications and wood treatments. As this field is rapidly expanding, we also include within the review trends from current research in order to gauge the state of the art, and likely direction of travel of the industry.

Chemical improvement of surfaces. Part 3: Covalent modification of Scots pine sapwood with substituted benzoates providing resistance to Aureobasidium pullulans staining fungi

Holzforschung ◽  
2015 ◽  
Vol 69 (5) ◽  
pp. 595-601 ◽  
Author(s):  
Jan C. Namyslo ◽  
Dieter E. Kaufmann ◽  
Carsten Mai ◽  
Holger Militz
Keyword(s):  
Scots Pine ◽  
Aureobasidium Pullulans ◽  
Covalent Modification ◽  
Attenuated Total Reflection ◽  
Chemically Modified ◽  
Covalently Bonded ◽  
Blue Stain ◽  
Natural Wood ◽  
The Individual ◽  
Modified Wood

Abstract The development of appropriate chemical precursors that can covalently functionalize natural wood aims at efficient restriction of deterioration. Biological staining experiments were performed with veneer pieces made of sapwood of Scots pine (Pinus sylvestris L.) that had previously been chemically modified with substituted benzoates. Based on the recently published protocol on esterification of wood by means of 1H-benzotriazole activation, the quantity of covalently bonded organomaterials (QCOs), a recently defined advantageous value considering the individual molecular weight of the functionalizing organochemical groups, was obtained in the range of 0.9–1.5 mmol g-1. The modified wood was analyzed by attenuated total reflection IR spectroscopy. Modification with three electronically different benzoates clearly reduced the colonization of the specimen’s surfaces by the blue stain fungus Aureobasidium pullulans but did not fully prevent it. The degree of colonization appeared to decrease with increasing QCO values of the modification agents but apparently did not strongly depend on the additional functionality of the benzoate.

Hydrophilic-Hydrophobic Characteristics of Wood-Polymer Composites Filled with Modified Wood Particles

2018 ◽  
Vol 762 ◽  
pp. 176-181
Author(s):  
Jevgenijs Jaunslavietis ◽  
Galia Shulga ◽  
Jurijs Ozolins ◽  
Brigita Neiberte ◽  
Anrijs Verovkins ◽  
...  
Keyword(s):  
Free Energy ◽  
Polymer Composites ◽  
Surface Free Energy ◽  
Moisture Sorption ◽  
Contact Angles ◽  
Work Of Adhesion ◽  
Wood Polymer ◽  
Wood Particles ◽  
Wood Polymer Composites ◽  
Modified Wood

In this study, hydrophobic-hydrophilic characteristics, including contact angle and moisture sorption of a modified wood filler and the wood-polymer composites (WPC) containing it was investigated. The wood filler obtained from aspen sawdust was modified by mild acid hydrolysis and by ammoxidation. Contact angles of the wood particles and the WPC samples were measured with Kruss K100M using the Washburn and Wilhelmy methods, respectively. Work of adhesion was calculated using Young-Dupre equation. Surface free energy as well as its dispersive and polar parts were found using Owens-Wendt-Rabel-Kaelble approach. It was found that the hydrolysis and the ammoxidation led to decrease of the hemicelluloses content in the lignocellulosic matrix. Beside this, the ammoxidation favours the formation of amide bonds in the ammoxidised particles. These changes enhanced the contact angles, decreased the work of adhesion, and decreased surface free energy of the WPC samples filled with the modified particles in comparison with the WPC sample that contained the unmodified ones. The treatment of the wood particles decreased the wettability towards water, but increased it towards recycled polypropylene. This positively effects mechanical properties of the samples.

scholarly journals CREEP AND REVERSE CREEP OF NATURAL AND PLASTICIZED BIRCH WOOD WHEN PRESSING ACROSS THE FIBERS.

2020 ◽  
Vol 10 (1) ◽  
pp. 145-152
Author(s):  
Oksana Shakirova
Keyword(s):  
Second Phase ◽  
Transverse Strain ◽  
Birch Wood ◽  
Entire Cross Section ◽  
Third Phase ◽  
Natural Wood ◽  
Reverse Creep ◽  
Dry Wood ◽  
Thermocatalytic Cracking ◽  
Time Changes

Pressed (modified) wood is a technological process of drying, impregnation and pressing (R 54577-2011 State Standard). The density of pressed wood, depending on the degree of pressing, ranges from 750 to 850 kg/m3. Strength, hardness toughness of this wood is several times greater than of natural wood. Coal oil, TCL (thermocatalytic cracking liquid), shale oil are most often used as wood antiseptics. They are plasticizers and change the nature of deformations during pressing.Experiments with natural and were conducted to obtain comparative data. Pressed wood contained 10% of TCL oily antiseptic by weight of absolute dry wood. Birch wood was used as the starting material. In this case, an antiseptic agent in an amount of 8-10% by weight of dry wood is evenly distributed over the entire cross section of the specimen. Direct and reverse creep was studied to assess time changes in deformation composition of wood, pressed across fibers. Measurements of direct and reverse creep of wood were carried out on a lever installation. The obtained modes can be used to optimize the technology of obtaining plasticized wood, because plasticization of wood with TCL oil reduces toughness 3-5 times (in the first phase of deformation), in the second phase - 1.1-1.5 times, in the third phase - 2.5-3 times. Transverse strain coefficient increases 1.2-1.3 times. Using creep curves of plasticized wood, it was found that oil impregnation gives 4-5 times greater reduction in the proportion of elastic deformations and, accordingly, increases the residual ones.

scholarly journals COMPARISON OF EFFICIENCY OF NATURAL AND SYNTHETIC IMPREGNATING COMPOSITIONS FOR BIRCH WOOD

2020 ◽  
Vol 8 (1) ◽  
pp. 193-198
Author(s):  
Larisa Belchinskaya ◽  
A. Dmitrenkov ◽  
Konstantin Zhuzhukin
Keyword(s):  
Water Absorption ◽  
Vegetable Oils ◽  
Wood Species ◽  
Sunflower Oil ◽  
Corn Oil ◽  
Engine Oil ◽  
Birch Wood ◽  
Hydrophobic Properties ◽  
Natural Wood ◽  
Oil Sunflower

The article is devoted to the study of technologies for the use of used motor and vegetable oils for hydrophobizing treatment of birch wood. In this work, synthetic and semi-synthetic engine oil is used to impregnate wood; spent corn oil, sunflower oil, organosilicon liquid GKZh-11, industrial impregnating composition of ZhTK. The effectiveness of the impregnating compositions is estimated by the indicators of water absorption and swelling in two mutually perpendicular directions (radial, tangential). Spent motor and vegetable oils saturate wood quite well and give it hydrophobic properties. At the same time, impregnation of birch wood with used engine oil (OMM) allows to improve water absorption of birch wood by 52.1% compared to natural wood and by 21% compared to water absorption. Thus, the processing of birch wood with used motor and vegetable oils makes it possible to utilize production waste and improve the properties of low-value wood species with a significant increase in its resistance to external influences.

scholarly journals Condition of production and operation of railway sleepers from various materials

2018 ◽  
Vol 7 (4) ◽  
pp. 157-166 ◽  
Author(s):  
Татьяна Курьянова ◽  
Tatyana Kuryanova ◽  
Алексей Платонов ◽  
Aleksey Platonov ◽  
Марина Михеевская ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Physical And Mechanical Properties ◽  
Railway Track ◽  
Natural Wood ◽  
Coniferous Wood ◽  
And Performance ◽  
Whole Life Cycle ◽  
Production And Operation ◽  
Modified Wood

Sleepers are elements of the upper structure of the railway track. When choosing a material for the manufacture of sleepers, we are based on such basic factors as cost for the whole life cycle and performance characteristics. In connection with the depletion of wood stocks in the world and the short life of wooden sleepers, the process of using sleepers made of reinforced concrete, metal and plastic goes intensively. The service life of pine sleepers is no more than 12-15 years, reinforced concrete sleepers are about 30-50 years old, plastic ones are up to 40 years old, and metal ones are 50-60 years old. However, wooden sleepers differ in the least cost, they practically do not have restrictions on the laying areas, and in some cases have a clear advantage over other materials. Reinforced concrete, metal and plastic sleepers are more expensive than wooden ones, have a longer payback period and are recommended to be laid on roads with high freight intensity, where they can pay off as quickly as possible. It is possible to reduce the shortcomings of sleepers made of natural wood, using modified hardwood for their manufacture, which, by pressing, will be stronger than the sleepers made of natural wood, which, in its physical and mechanical properties, is not inferior to sleepers made of natural coniferous wood. However, a certain disadvantage of the modified wood is its ability to change size and shape with increasing humidity. Stabilization of sizes and forms of modified wood can be increased by impregnating it with the composition of antiseptic with stabilizer. The predicted service life of sleepers from modified wood can be significantly higher than that of wooden sleepers made of natural coniferous wood.

Deformation Behavior of Natural Wood Having Hierarchical Structure Under A Compression State

2011 ◽  
Vol 1304 ◽  
Author(s):  
Tsunehisa MIKI ◽  
Hiroyuki SUGIMOTO ◽  
Kozo KANAYAMA
Keyword(s):  
Plastic Deformation ◽  
Flow Stress ◽  
Hierarchical Structure ◽  
Deformation Behavior ◽  
Elevated Temperatures ◽  
Longitudinal Direction ◽  
Metallic Materials ◽  
The Hierarchical Structure ◽  
Natural Wood ◽  
Shear Flow Stress

ABSTRACTA large deformation of bulk wood using slipping between the wood cells has been found just like a plastic deformation generated by slip band in metallic materials. This phenomenon is caused by the hierarchical structure of the wood cell, and the intercellular layer becomes selectively softened in moistened states of wood. In such conditions, bulk wood subject to compression at elevated temperatures can easily be deformed perpendicular to the longitudinal direction of the cells by shear flow stress after being collapsed.

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