Search results

The purpose of this work was to study the effect of different wood surface preparations on the wetting and adhesion of coating.

In this research, six different chemical preparations to evaluate the photostability and properties of wood coating. Also, the effect of the same wood treatments on the properties of the coating, i.e. wetting, adhesion and the permeability of two types of coatings, was investigated.

As a result, benzoyl chloride and chromic acid were found to be the most effective photostabilizing preparations. Solvent-based polyurethane was more compatible with the prepared wood surfaces compared with water-based alkyd coatings.

Chemical modifications of wood surfaces affected the wetting of various coatings.

Various surface properties could be changed using preparation that affects important coating properties.

Unfortunately, the properties of transparent wood coatings used outdoors disappear through the early years of use, essentially due to the wood substrate’s photodegradation.

Wood is a widespread substrate because of its comfortable handling, availability, proper cost of preparation and its good mechanical strength because of its density. Architects and designers tend to use wood in the construction of green buildings. However, this material is disposed to weathering while using outdoors and it should be solved.

The purpose of the study is to show an improvement in resistance (permeability) and durability (residual strength) of modified wood compared to natural wood.

A relevance way to increase the durability and resistance of wood is processing with polymers. Novosibirsk State Technical University, Novosibirsk State University of Architecture and Civil Engineering (Sibstrin) and the Norilsk State Industrial Institute researched the resistance of elements of mine treatment plants made of wood modified with synthetic polymers. The study was carried out according to V.A. Kucherenko. Modification of such species as birch and pine can significantly increase wood resources by extending its service life and improving its physical and mechanical properties. Latex-organosilicon modifier was used as a modifier.

Latex clogs the capillaries of wood, preventing the penetration of aggressive solutions into it, and potassium methyl silicate interacts with hydrophilic OH groups, increasing the water-repellent properties of the surface of cells and wood capillaries.

The results of long-term and predictive tests of modified wood in aggressive environments of treatment facilities are presented. As a result, diffusion of aggressive media into the wood becomes more difficult and its resistance and durability increase.

This paper aims to show the potential decay resistance of furfurylated wood and investigate possible eco‐toxicity of such materials produced. This paper deals with the environmental aspects and durability of furfurylated wood, both laboratory and field tests are included in the investigations. Results from several decay tests, emission analysis studies and ecotox tests are presented. The results show that furfurylated wood is highly decay resistant. Furthermore, no significant increase in eco‐toxicity of leaching water was found and degradation through combustion does not release any volatile organic compounds or poly‐aromatic hydrocarbons above normal levels for wood combustion. Durability enhancement by furfurylation of wood is not believed to be harmful to the environment. Wood modified with furfuryl alcohol, “furfurylated wood”, is currently being marketed as a non‐toxic alternative to traditional preservative treated wood (wood impregnated with biocides). This paper summarises much of the long term exposure of furfurylated wood ever caried out, and present the first eco‐tox tests on such material ever done.

The paper aims to present an investigation of wood bonding strength as a very important indicator for effective using in further manufacturing processes.

In this study, the wood bonding strength sensitivity was estimated based on grain orientation, feed speed, heating time and temperature, temperature and type of adhesive. Artificial intelligence methods were applied for this analysis because it is strongly a nonlinear process.

It was shown that the artificial intelligence tools could be useful, reliable and effective for the wood bonding strength sensitivity estimation. Afterwards the power consumption in in solid wood machining process is analyzed and estimated by the artificial intelligence tools.

Results shown that the wood bonding strength is the most sensitive for type of adhesive. Thus, the results of the present research can be successfully applied in the wood industry to reduce the time, energy and high experimental costs.

The objective of this study is to evaluate the water repellent efficiency of some oil modified solvent‐type alkyd resins, as wood protective formulations (WPs). It was done by surface treating of pine and cedar woods with the five leading brand of alkyd resins that are available in Turkey.

For effective water repellency, various formulations were made by incorporating different concentrations of varnish resin, pigment, solvent, and a substance that repels water. The impact and adhesive strengths of the five different solvent‐type alkyd resins were characterised by using a very simple experimental design.

The swelling variations of unmodified pine and cedar woods were determined in water. Next, the water repellent efficiency of the five different alkyd resin formulations was evaluated. The modification of pine and cedar woods using alkyd resins showed various level enhancement of resistance against water over the unmodified samples. The modification caused a chemical linkage between surface and resin that led to ensuring the intrinsically chemical bonds across the wood/resin matrix interface, which was the main cause to the improved water resistance. However, some WPs were less compatible, hence, had less bonding potential to both woods.

The method developed provided a simple and practical solution to selecting WPs (brands) for pine and cedar woods.

The method for evaluating adhesive strengths of the five different brand solvent‐type alkyd resins to pine and cedar woods were novel and could find numerous applications in surface coating.

To investigate the effects of acetylation process as a chemical treatment method to improve the dimensional stability of wood, or as a pre‐treatment step to enhance the dimensional stability of wood by impregnates.

Esterification of two species of wood were carried out by vapour and liquid phase acetylation processes. With the vapour phase acetylation process, wood with different acetyl contents were obtained by changing the length of time of treatment. With the liquid phase acetylation, different acetyl content were obtained by changing the acetylating mixture or by activating wood with acetic acid for different periods of time and at different temperatures prior to the acetylation processes. The acetyl content and the conditions of impregnation improving the dimensional stability were modelled and optimised. The success of acetylation process for improving the affinity of wood towards the impregnation was also demonstrated.

Vapour phase acetylation process was preferable over liquid phase acetylation for improving both water resistance and dimensional stability of wood species examined. Liquid acetylating of wood, as a pre‐treatment step enhanced the effect of impregnates, especially the linseed oil to improve relevant wood properties. The greater improvement was obtained at 3 h impregnation time and 190°C curing temperature for 1 h.

Despite the success in improving the affinity of wood species to novolac by pre‐acetylation, increasing the curing time and curing temperature led to deterioration of the water resistance and dimensional stability.

Pre‐acetylation of the wood provided a practical solution to rendering the natural wood greater water resistance property using commercial impregnates.

The method for acetylation of wood prior to impregnation was novel and could be used for inhibiting wood against moisture absorption during storage.

Heat treatment reduces hygroscopicity and accompanying dimensional changes in wood. Prior to coating, pine and spruce boards were heat treated at 225°C for six hours under steam, in order to achieve dimensional stability and durability of wood substrate. The panels were coated surface finishes which are commonly used on exterior cladding, joinery and fences in Finland. Performance of the coated heat‐treated and untreated panels was monitored during five years’ outdoor exposure. Without coating the heat‐treated wood is not weather resistant. The original dark brown colour of the uncoated heat‐treated wood panels was not stable when exposed to weather, turning grey. Cracking of the heat‐treated wood without coating was at the same level as that of the untreated wood despite the lower moisture content of the heat‐treated wood. The unpigmented or low build stains and oils did not prevent cracking of the heat‐treated wood. Weather resistance of the heat‐treated wood was improved by the water‐ or solvent‐borne paints. Wood heat treated by means of this process is comparable to untreated wood as a substrate for coatings and no alterations in coating recommendations are needed when considering coating of heat‐treated wood.

Impermeability tests had been carried out to compare the moisture resistance of two wood finish paints available on the Cameroonian market. Two types of paints had been used namely, an oil‐based paint and an emulsion paint, both manufactured in Cameroon by SMALTO Company. It appeared that the oil‐based paint gave better protection to wood in wet environments, areas with strong pluviometry (where the quantity of humidity in the air is very high). The emulsion paint was found to be suitable for use for interior decorative purpose. It was suggested that a glycerophthalic lacquer could be used for wood finishing in areas subjected to the emissions of water vapour or requiring frequent washing (bathroom, kitchen, WC, etc.). In addition, the number of coating layers should be increased to enhance the moisture resistance of such paint films.

This study aims to present a state-of-the-art review of building information modelling (BIM) in the Swedish construction practice with a focus on wood construction. It focuses on examining the extent, maturity and actual practices of BIM in the Swedish wood construction industry, by analysing practitioners’ perspectives on the current state of BIM and its perceived benefits.

A qualitative approach was selected, given the study’s exploratory character. Initially, an extensive review was undertaken to examine the current state of BIM utilisation and its associated advantages within the construction industry. Subsequently, empirical data were acquired through semi-structured interviews featuring open-ended questions, aimed at comprehensively assessing the prevailing extent of BIM integration within the Swedish wood construction sector.

The research concluded that the wood construction industry in Sweden is shifting towards BIM on different levels, where in some cases, the level of implementation is still modest. It should be emphasised that the wood construction industry in Sweden is not realising the full potential of BIM. The industry is still using a combination of BIM and traditional methods, thus, limiting the benefits that full BIM implementation could offer the industry.

This study provided empirical evidence on the current perceptions and state of practice of the Swedish wood construction industry regarding BIM maturity.

Using a soft-hard continuum of drivers and barriers, this research seeks to explain wood companies' adoption of circular economy (CE) practices.

Multiple interviews, complemented by secondary documents and site observations were used to investigate three wood-based companies that have adopted CE practices. The 10R framework and soft-hard continuum are used to guide data analysis.

The adoption of 10R practices were explained by soft-factor incentives of leaders' values and vision and openness for innovation, all within a regulatory void, and eventually overcome hard-factor barriers of process development, supply chain capability and customer behaviours at product end-of-life.

Crucial for CE model adoption are leaders' positive attitudes, subsequently grown across the companies. The 10Rs are a prompt for CE practice adoption to capture and retain value and generate revenue. Collaboration across the supply chain, including customers and other value capture companies (e.g. repurposing companies), is essential to maximise value retention. Government should play an increased soft-factor incentive regulatory role and support CE practices to overcome hard-factor barriers.

This study contributes an explanation of CE adoption within a relatively unsupported context. Despite the regulatory void, CE practice adoption was driven by leader values. To achieve their vision and overcome the numerous barriers, suppliers and customers required a large investment in education. Indeed, customer behaviour, previously thought to be an incentive for CE adoption, is also identified as a barrier.