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Wood is one of the materials that is used for building construction either as structural member or as finishes from ages past to contemporary generation. It is composed of elongated, hollow spindle shaped cells that are arranged parallel to each other along the trunk of a tree. The resistance to water, chemicals, strength properties, appearance and decay rate is dictated by the fibrous cells. The purpose of this paper was to examine the application and use of wooden floor finish (an extract from wood) in residential buildings in Lagos, Nigeria, with a view to determine its effectiveness.

The study adopted a dual stage survey approach before the administration of questionnaire on 100 respondents that were selected through purposive sampling after the initial inquiry on the use of the material from 384 randomly selected samples from the entire population.

The study shows that the material is applied in all interior spaces except bathrooms and toilets. Minimal adoption is also seen in the kitchen area. Users indicate that wooden floor finish requires little maintenance, has low impact on users' health, considered safe-minimal occurrence of home accidents is recorded, has moderate thermal insulation and affordable.

The usage has impact on the environment due to continuous lumbering activities and lack of adequate plan for reforestation. This suggests that its sustainability depends on afforestation programmes. Its poor performance in sound insulation, water and fire resistance requires further attention. The maintenance is relatively easy and affordable.

The author made a new foray into investigating the performance of wooden floor finish due to its resurgence in the area bearing in mind the unseasoned condition of wood in circulation in the area. Previous adoptions were done by a less aggressive generation of well-trained artisans. Best places for its usage within the interior spaces are identified.

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.

The surface characteristics of wood such as surface roughness, surface free energy (SFE) and wettability are important properties influencing further manufacturing processes such as gluing and coating. The purpose of this study is to determine the influence of surface roughness of ten tropical woods on their SFE, wettability and bonding quality for water-based acrylic and solvent-based alkyd varnishes.

The woods tested in this study were fast-growing teak, afrika, sungkai, mindi, merbau, durian, lamtoro, pulai, acacia and kempas. Wood surfaces were prepared in unsanded and sanded using an abrasive paper of 120 grits. SFE values were calculated based on the Rabel method. Wettability values were measured based on the contact angle between varnish liquids and wood surfaces using the sessile drop method, and the S/G model was used to evaluate the wettability of the varnishes on the woods surface. The bonding quality of the varnishes was measured using a cross-cut test based on the ASTM 3359-02 standard.

The results show that unsanded kempas wood had the roughest surface with a Ra value of 16.24 µm, whereas sanded lamtoro wood has the smoothest surface with a Ra value of 6.86 µm. The unsanded afrika wood had the highest SFE value of 53.61 mJ/m², whereas sanded fast-growing teak had the lowest SFE value of 36.17 mJ/m². Sanded merbau woods had the lowest K value of 0.022 for the water-based acrylic varnish, whereas unsanded afrika wood had the highest K value of 9.253 for the alkyd varnish. Afrika wood with the highest K values (highest wettability) for both acrylic and alkyd varnishes produced the highest bonding quality (grade 4-5). Compared to the water-based acrylic varnish, the solvent-based alkyd varnish was more wettable and generated better bonding quality.

Improving the quality of fast-growing wood from plantation by painting could be considered to increase their use for higher value wood products.

Compared to water-based acrylic varnish, solvent-based alkyd varnish was more wettable and generated better bonding quality.

The originality of this research is to evaluate the values of surface free energy. SFE could be used to quantitatively determined the wettability of paints liquid in the surface of wood

Different types of wood (ash, oak and beech) have been activated by new activation method. The aim of this work is to study the effect of different types of wood on the physical and chemical properties of Ni/Pd coatings.

The wood was activated by ablation of the Pd target using pulsed laser deposition (PLD) technique. Different diagnostic techniques such as X-ray photoelectron spectroscopy (XPS), attenuated total reflection (ATR) spectroscopy and energy dispersed X-ray spectroscopy (EDS), in parallel with scanning electron microscopy (SEM) were used to achieve this goal.

The XPS technique confirmed that the highest concentration of Pd was found in the Pd/beech sample, which is associated to the texture of the beech wood substrate surface. EDS results confirmed the absence of any contamination related to electroless plating method. It is concluded that the wood morphology and its surface roughness play a conclusive role to obtain different quantity of metal by PLD and electroless plating methods.

Although several works have been performed to study the influence of substrates on the coated metals and away of the traditional methods in activating non-catalytic surface, in this paper, PLD method is used to obtain a good quantity of Pd distributed on the entire surface and inside the porous of the wood. This study could be considered as a step investigation for understanding the role of the wood substrate morphology on the physical and chemical properties of films. To our knowledge, there are no works of combining a coated Ni/Pd by electroless plating and PLD methods on wood.

In fire condition, the time to failure of a timber connection is mainly reliant on the wood charring rate, the strength of the residual wood section, and the limiting temperature of the steel connectors involved in the connection. The purpose of this study is to experimentally investigate the effects of loaded bolt end distance, number of bolt rows, and the existence of perpendicular-to-wood grain reinforcement on the structural fire behavior of semi-rigid glued-laminated timber (glulam) beam-to-column connections that used steel bolts and concealed steel plate connectors.

In total, 16 beam-to-column connections, which were fabricated in wood-steel-wood bolted connection configurations, in eight large-scale sub-frame test assemblies were exposed to elevated temperatures that followed CAN/ULC-S101 standard time-temperature curve, while being subjected to monotonic loading. The beam-to-column connections of four of the eight test assemblies were reinforced perpendicular to the wood grain using self-tapping screws (STS). Fire tests were terminated upon achieving the failure criterion, which predominantly was dependent on the connection’s maximum allowed rotation.

Experimental results revealed that increasing the number of bolt rows from two to three, each of two bolts, increased the connection’s time to failure by a greater time increment than that achieved by increasing the bolt end distance from four- to five-times the bolt diameter. Also, the use of STS reinforcement increased the connection’s time to failure by greater time increments than those achieved by increasing the number of bolt rows or the bolt end distance.

The invaluable experimental data obtained from this study can be effectively used to provide insight and better understanding on how mass-timber glulam bolted connections can behave in fire condition. This can also help in further improving the existing design guidelines for mass-timber structures. Currently, beam-to-column wood connections are designed mainly as axially loaded connections with no guidelines available for determining the fire resistance of timber connections exerting any degree of moment-resisting capability.