Varnished Wood Research Articles

Effect of wood varnish coating on the water absorption and mechanical properties of jute fiber reinforced epoxy composites

Natural fiber-reinforced composites are becoming popular day by day because of their low cost and renewable nature. However, a major concern of these composites is water absorption. To minimize the water absorption in natural fiber-reinforced composites, wood varnish coating was used in this paper to investigate the effect of this coating on water absorption and mechanical properties of jute fiber-reinforced composites. Four types of composites were fabricated using the hand lay-up technique, among them on Type 1 no coating was used, Type 2 was surface coated, Type 3 was fiber coated and Type 4 was both fiber and composite surface coated. Water absorption, tensile, bending, short beam shear, and impact tests were performed on the composite specimens according to their respective ASTM standards to see the effect of coating. Both fiber and fracture surface morphology were observed using Scanning Electron Microscope. It was found that the water absorption was significantly reduced for Type 2 (50.31 %) and Type 4 (56.01 %) specimens. However, the tensile strength and bending strength were reduced by 74.17 %, and 72.71 % for Type 3 and 77.07 % and 84.24 % for Type 4 composites while for Type 2, they were slightly increased (7.26 % and 1.13 %). The ILSS of Type 3 and Type 4 were reduced by 69.34 % and 58.07 % respectively while it was reduced by only 4.49 % for Type 2 composite. On the other hand, the impact energy absorption was increased by 85.32 % for Type 4 composite. The findings of this study suggest that Type 2 composite (only composite surface coating) has the overall best performance and wood varnish coating has the potential to reduce the water absorption on natural fiber-reinforced composites.

A Comparative Analysis of Tannin and Commercial Fire Retardants in Wood Fire Protection

In civil construction, one of the primary challenges associated with wood application is its high flammability and low durability during fires. Although chemical treatment with fire-retardant properties exists, they are expensive and of non-renewable origin. Tannin, a wood extractive, being a phenolic compound, holds promise for enhancing the thermal properties of wood. This study aimed to assess the efficacy of tannin as a fire retardant and compare it with a commercial product, as well as comparing different application techniques for these products. Wood samples from the Simarouba amara Aubl. species were utilized. Tannin and a commercial flame retardant were applied via immersion, vacuum impregnation, brushing, and a treatment of tannin incorporated into water-based wood varnish. Alongside the burning test performance, assessments of the wood’s physical properties, such as colorimetry, thermal stability, and mass retention, were conducted. The application of tannin altered the wood’s color and reduced the spread of fire; its presence significantly reduced the flame duration and maintained the wood’s structural integrity. However, tannin retention was lower compared to commercial flame retardant, leading to reduced fire retardancy. Among the methods tested, immersion proved to be the most effective in enhancing the wood’s resistance to flame contact.

Natural weathering effects on the surface morphological and physicochemical properties of radiation curable coatings in tropical climate

The purpose of this research is to discover the effects of natural weathering on palm oil-based and petrochemical-based film coatings. The film coatings were prepared using the radiation curing approach via cross-linking. Three palm oil-based resins with TiO2 nanoparticle loading were developed: EPOLA, EPOLA-OPV, and POBUA. The petrochemical-based coatings were also developed to compare the performance of natural and synthetic coatings. The coatings were exposed to natural weathering for up to 60 days at varied angles of 0°, 45°, and 90°. The effect of natural weathering conditions on the surface morphological, physiochemical, and also flexural characteristics of coatings, as well as the discoloration visual inspection and the growth of mould or fungus on the tested specimen, was studied. The results showed that natural weathering exposure induced severe discoloration and deterioration of the polymer network structure of the coatings due to photo-oxidation reaction and the presence of fungi. Overall, palm oil-based coatings deteriorate slower than petroleum-based coatings, especially at a 90° angle. This study indicated that bioresources-based palm oil has a significant potential for interior wood varnish applications due to its superior qualities over synthetic-based coatings.

Tunable Acoustic Properties Using Different Coating Systems on Resonance Spruce Wood

AbstractThe study investigates the effect of the type of varnish and the number of layers on some acoustic properties of the resonance spruce in combination with the changes produced in some physical, morphological, and chemical properties of wood. In addition to color changes and surface chemistry, the surface roughness and morphology are modified by the thickness of the varnish film, 10 layers being optimal from this point of view, as well as the oil‐based finish. The sound absorption coefficient increases with the number of varnish layers and varies with the sound frequency range, varnish type, and wood quality, all contributing to the acoustic tunability. For example, for a sound frequency of 1.5 kHz, it is observed that the oil‐based varnish with 5 and 10 layers contributes to a full sound, while the alcohol varnish, due to a lower absorption coefficient for this frequency, can lead to some nasal sounds. Applying more than 10 layers of varnish does not improve the sound performance as it will soften the sound in an oil‐based finish and make the sound too sharp in the case of alcohol–varnished wood.

Performance of Spray-Dried Nanofibrillated Cellulose as Wood Varnish Reinforcement in Outdoor Environment

Performance of Spray-Dried Nanofibrillated Cellulose as Wood Varnish Reinforcement in Outdoor Environment

The Effect of Hot and Cold Check Tests on Surface Roughness and Glossiness in Varnished Wood Material

In this study, specimens from Scots pine (Pinus sylvestris L.), Anatolian chestnut (Castanea sativa Mill.) and Eastern beech (Fagus orientalis Lipsky) tree species, prepared according to ISO 3129, were conditioned according to TS ISO 13061-1. Cellulosic varnish, water-based varnish, and glass polish varnish were applied to their surfaces in accordance with ASTM-D 3023 principles. In the study, roughness (TS 2495 EN ISO 3274 and TS EN ISO 21920-3) and gloss (according to TS EN ISO 2813) values of the samples were calculated after hot and cold check test. Varnished test specimens prepared in 100 mm × 100 mm ×10 mm dimensions were first kept in drying oven at (50±5) °C for 1 hour, then were kept in conditioning room for 1 hour, and then at (-20±2) °C for 1 hour, according to ASTM D1211-97. These processes were accepted as one cycle, and tests were continued until 15 cycles. Afterward, glossiness was measured as perpendicular and parallel to fibers at 60º with a gloss measurement device, and surface roughness values of Ra and Rz were determined with a surface roughness measuring device. According to the results obtained, Scots pine (Pinus sylvestris L.), Eastern beech (Fagus Orientalis Lipsky), and Anatolian chestnut (Castanea sativa Mill.) varnish-coated wood material surfaces all showed a decrease in gloss values after hot-cold shock effect. While an increase occurred in Rz values of roughness for all wooden surfaces, Ra values roughness increased for Scots pine and chestnut and decreased for eastern beech. Gloss and roughness values of surface-treated wood materials against changing weather conditions can determine usefulness of the surface material used. The findings obtained in this study can be useful to manufacturers who use wooden products in the design of marine vehicles and those who export furniture to countries in different climatic conditions.

Construction and characterization of superhydrophobic wood coatings using one-step technique

This study was aiming at enhancing the stain resistance and durability of varnish on wood surfaces, a super hydrophobic solution was created by blending the synthetic ZIF-8/paraffin with Hexadecyltrimethoxysilane (HDTMS) at a specified mass ratio. This superhydrophobic mixture was then directly applied onto the wood varnish coating using a one-step method. The microscopic characterization, transmittance, wear resistance, and water contact angle (WCA) tests of hydrophobic coatings indicated that the mass ratio of ZIF-8 to HDTMS affected the surface microstructure and roughness of wood coatings. When the ratio reached 10:1, 5:1, and 2:1, the nanoparticles were dispersed at the interface of the varnish, and the film forming effect was uniform. The transmittance of the varnish coating was about 90%, and the transmittance of the superhydrophobic coating was about 80%. The water absorption rate of the treated sample was much lower than that of the untreated sample. After 10 cycles of abrasion tests, while the WCA decreased, it remained above 150°. Water droplets on the coating surface can remove pollutants through “rolling washing”, demonstrating good self-cleaning performance. The one-step method enables the rapid creation of superhydrophobic films on the surface of wood varnish coating.

Preparation and characterization of a silicone RAFT-modified aqueous acrylic resin coating for wood antifouling

Anionic emulsifiers, synthesized from novel silicone RAFT reagents (RAFT-PDMS), acrylic acid, lauryl methacrylate, and methyl methacrylate, were used to create a macromolecular silicone-modified polyacrylate aqueous emulsion. This emulsion was prepared by copolymerizing the custom-made anionic emulsifier with hydroxyethyl acrylate and other monomers. The emulsion underwent crosslinking with isocyanate, leading to a novel aqueous wood varnish incorporating polydimethylsiloxane chain segments. The structural features of RAFT-PDMS were characterized using 1HNMR, Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible Absorption Spectroscopy (UV–VIS), and Energy-Dispersive X-ray Spectroscopy (EDS). By adjusting the degree of polymerization and content of RAFT-PDMS, emulsions with a core-shell structure were generated. The impact of RAFT-PDMS on the molecular weight, particle size, and thermal properties of the latex was evaluated. Studies demonstrated that the applied wood coatings reduced surface roughness while enhancing gloss and hydrophobicity. Further tests revealed excellent antifouling properties and resistance to both acid and alkali for the coating. This type of wood paint could address challenges associated with the difficulty of combining large molecule organosilicones with wood, thereby offering a novel approach for wood paint applications.

A non-invasive study of the effect of three commercial cleaning products on shellac-coated mahogany

The Royal Palace of Norway has a large 19th century wooden furniture collection and most of it is coated with shellac-based varnishes. Since these objects are part of the royal collections, they are still in daily use at the different residences and, therefore, need to be frequently cleaned. In this work, the effect of three cleaning commercial products (Baolin, Centurio, Fulgentin) used at the royal collections on shellac-coated mahogany is investigated for the first time. A non-invasive methodology (portable ER-FTIR spectroscopy and colorimetry) was applied to assess whether the chemical composition and the color of fresh and artificially aged mahogany wood mock-ups coated with shellac were affected by the above-mentioned cleaning products. This study shows that one of them causes changes in the varnished wood, thus potentially affecting the long-term conservation of this furniture collection.

Violin Varnishes: Microstructure and Nanomechanical Analysis.

The aim of the current work is twofold: to demonstrate the application of in situ non-invasive imaging by portable atomic force microscopy (AFM) on the surfaces of a violin and to integrate compositional and mechanical analysis at the nano scale level on model samples of varnished wood. These samples were prepared according to traditional recipes by an Italian lute-maker family well practised in the art. Samples of oil and spirit-based varnishes on maple wood, naturally and accelerated light aged, were studied. AFM was used to measure the nanomechanical properties of the model samples and established that the spirit-based varnish was stiffer than the oil-based. Synchrotron radiation micro- Fourier Transform Infra-red analysis of the layer structure revealed that stiffer spirit-based varnish showed less penetration into the wood than the oil-based. Further PeakForce Quantitative Nanomechanical Mapping (QNM) demonstrated a difference in adhesion values between the oil- and spirit-based samples.

The effect of heat treatment method and process temperature on the glossiness of polyurethane varnishes applied to wood material surfaces

Bu çalışmada, farklı yöntemlerle ve farklı sıcaklık seviyelerinde ısıl işlemli ağaç malzeme yüzeylerine uygulanan poliüretan verniklerin parlaklık özellikleri incelenmiştir. Kayın (Fagus sylvatica L.) ve sarıçam (Pinus silvestris L.) odunu örnekleri üç farklı yöntem (ThermoWood, yağlı işlem ve sıcak hava) ve üç farklı sıcaklık (170 °C, 190 °C ve 210 °C) uygulanarak ısıl işleme tabi tutulmuştur. Daha sonra örnek yüzeyleri endüstriyel uygulamalara göre poliüretan vernik ile kaplanmıştır. Parlaklık ölçümleri TS EN ISO 2813 esaslarına uyularak gerçekleştirilmiştir. Verniksiz örnekler için, yağlı işlem yöntemi ile ısıl işlem görmüş örneklerde daha düşük parlaklık değerleri belirlenmiştir. ThermoWood ve sıcak hava yöntemleri ile muamele edilmiş örneklerde parlaklık değerleri benzer bulunmuş ve bu örneklerde, düşük sıcaklıktaki (170 °C) ısıl işlem sonrası parlaklıklar kontrol örneklere göre artmıştır. Vernikli örneklerde ise ısıl işlem yönteminin etkisi parlaklık üzerinde önemsiz bulunmuştur. Diğer taraftan, hem verniksiz hem de vernik uygulanmış örneklerde ısıl işlem sıcaklığı artışına bağlı olarak yüzey parlaklık değerleri azalmıştır.

Surface Roughness of Varnished Wood Pre-Treated Using Sanding and Thermal Compression

Surface roughness is an important factor during the processes of wood gluing and finishing. This study proposed a new approach for the preparation of wood veneer surfaces before varnishing through the use of thermal compression instead of sanding. The quality of the pre-treated surface was examined using surface roughness measurements. In the experiment, a wood veneer of black alder and birch, before varnishing, was subjected to sanding with a sandpaper of 180 grit size, and thermal compression at temperatures of 180 and 210 °C. Three different types of commercially manufactured varnishes (water-based (WB), polyurethane (PUR) and UV-cured (UV)) were applied to the prepared veneer surfaces with various numbers of varnish layers. Seven roughness parameters such as Ra, Rz, Rq, Rp, Rv, Rsk, and Rku were determined for the sanded and thermally densified unvarnished and varnished surfaces. The profile surface was recorded with a portable surface roughness tester along and across the wood fibers. It was found that there was no difference between the surface roughnesses of the surfaces that had been sanded and the surface roughnesses of those that had been thermally densified at a temperature of 210 °C. The research suggests that thermal compression at a temperature of 210 °C is enough to obtain smoother surfaces with a UV varnish system, and this process can be recommended as a replacement for sanding before varnishing as the most labor-intensive and expensive operations in woodworking industry. Applying two layers of varnish along with intermediate sanding was also sufficient to obtain a satisfactory finish.

Forensic Electrochemistry: Electrochemical Analysis of Trace Methamphetamine Residues on Household Surfaces

Illicit methamphetamine is known to be the most manufactured amphetamine-type stimulants worldwide. Relatively simple manufacturing procedure had resulted in the creations of manufacturing sites in a variety of premises and structures, deserving forensic investigation. Therefore, this study was aimed to develop an electrochemical detection technique to determine the residual methamphetamine contamination on various surfaces. Carbon materials, namely graphene oxide, graphene nanoplatelets, graphene ink, and glassy carbon microsphere modified glassy carbon electrode were used in detecting methamphetamine by differential pulse voltammetry (DPV). The surface morphology modified electrode was characterised and its electrochemical behaviour was determined. Under optimal conditions, the calibration curve showed bilinear in the concentration range of 1−40 μM and 40−120 μM with good precision and accuracy. The limit of detection was determined to be 0.3 μM. Graphene oxide modified electrode coupled with DPV successfully detected the residual methamphetamine on four household surfaces, including glass, stainless steel, plastic, and varnished wood with recoveries greater than 82%. To conclude, a novel electrochemical detection technique for the presence of methamphetamine was successfully developed to be applied in clandestine laboratory settings. It would be beneficial to assist the forensic investigation, especially for those forensic evidence recovered from suspicious and suspected clandestine laboratories.

Plants for making wooden bowls and related traditional knowledge in the Gyirong Valley, Tibet, China

BackgroundThe wooden bowl is an important symbol of the Tibetan cultures, yet, in China, little has been documented regarding the raw materials used to make these items as well as their cultural significance in Tibet. This study explores the ethnobotanical uses of plants used to make wooden bowls to understand their sustainability, cultural significance, and current status of related traditional knowledge in Gyirong Town, which is one of the most famous places for wooden bowl making.Materials and methodsBetween 2019 and 2021, key informant interviews, semi-structured interviews, and participatory observations were used to conduct ethnobotanical field surveys in Gyirong Valley. The field work was performed with the assistance of local guides. In this study, we utilized a use-report (UR) to reflect the number of mentions of a species by locals.ResultsOur results show that 16 different plants are used during the wooden bowl making process, of which nine are used as raw materials, three for dyeing, and four for varnishing. Although communities rely heavily on these plants, good management and collection methods were observed. We also documented the use of Fallopia denticulata as a red dye and four species of Impatiens as wood varnishes for the first time.ConclusionThe wooden bowl craftsmen and their housewives have a wealth of traditional knowledge of using plants to make wooden bowls in Gyirong Town. And the wooden bowls are now also offering benefits to the locals as well. The government and local people are committed to the protection and development of traditional knowledge related to wooden bowls, and this knowledge maintains a healthy degree of vitality. This research can provide insights into the vitality of traditional handicrafts that are facing challenges and promote their protection.

Keberhasilan Identifikasi Sampel Darah Kering yang Dipaparkan pada Beragam Jenis Substrat Kayu dengan Kondisi Lingkungan Berbeda Selama Kurun Waktu Tertentu

Most of the criminal cases leave traces at the TKP (Tempat Kejadian Perkara) which can be used as evidence to reveal the culprit and the chronology of events that have occurred. Blood is the most important biological evidence in TKP. Through experimental research with a completely randomized design (CRD), this study aims to determine the success rate of blood groups identification in different types of Sengon (Paraserianthes falcataria L. Nielsen) as wood substrate in open and closed environmental conditions up to a certain time period. The four variations of Sengon wood substrate used were natural wood, processed wood, painted wood, and varnished wood. After 336 hours exposure on wood substrate, blood sample on the substrate was confirmed to identify the ABO system blood group using the absorption-elusion method. The results showed that the success rate identification the blood groups in ABO system on all types of Sengon wood substrate in closed environmental conditions reached a 100% for observation periods until 336 hours. Despite, the success rate of blood identification from all types wood substrate in open environmental condition were 0% for observation periods until 336 hours. Those data was then tested for normality with SPSS. The results showed that the data are not normally distributed (sig >0,00) for all type of treatmment. So that non-parametric statistical tests were carried out. The results of the Kruskall Wallis test showed that there was no significant difference between the treatment of Sengon wood substrate types and also in the length of time of observation (sig value 1,000). While the significance value on the environmental condition variable is 0.000, so it was concluded that there was a significant success rate's differences of blood group identification in samples that exposed to an open environment compared to a closed environment. This is reinforced by the results of the Kendall's correlation test and Spearman's test which show a strong correlation between the percentage of successful identification of blood groups and environmental conditions (correlation of 1,000). While the correlation value between the percentage of successful identification of blood group with the type of substrate and the length of time of exposure are 0.000 and 0.000, which is indicates a very weak correlation between the percentage of success of blood group with the type of substrate and the length of time of exposure. It can be concluded that the four types of wood substrates in closed environmental conditions had the same good ability to preserve blood within an exposure time of up to 336 hours. But, sample exposure in a closed environment provides the best percentage of success rate identification the blood groups in ABO system rather than the open environment was.

S2631 Porphyria Cutanea Tarda, Type 2, in a Man With a Novel UROD Mutation

Introduction: Porphyria cutanea tarda (PCT) is usually caused by acquired defects in uroporphyrinogen decarboxylase (UROD) activity in the liver. 20% of cases occur in patients who have a genetically determined partial decrease in UROD activity. We describe a case of a man with a novel UROD mutation causing PCT type 2. Case Description/Methods: A 77-year-old man was evaluated for 6 months of painful blistering over his dorsal hands, forearms and head [Fig 1a]. His medical history was notable for hypertension, melanoma, and stroke. He reported heavy alcohol and tobacco use. He had no family history of porphyria. He worked for years at a manufacturing facility, with exposure to various industrial chemicals. More recently, he had exposure to weed killers, carburetor cleaners, and wood varnish. Exam revealed tense bullae with milia and hyperpigmented macules on dorsal hands and forearms. Biopsies revealed a subepidermal blister containing a small number of neutrophils with fibrin and evidence of festooning of the vessels consistent with porphyria. Labs revealed AST 63 U/L, ALT 64 U/L, alkaline phosphatase 54 U/L, and total bilirubin 0.8 mg/dL. Iron profile was unremarkable, and antibodies against HIV and hepatitis A, B and C were negative. Total plasma porphyrins were elevated to 13.4 mcg/dL. Fractionated urine, stool and plasma porphyrin levels were obtained [Table 1]. Urinary uro- and hepta-carboxyl porphyrins were markedly elevated, consistent with PCT. The patient was advised to start hydroxychloroquine 100 mg 3 times weekly and to avoid alcohol, tobacco use and sun exposure. Genetic testing revealed a novel mutation of UROD gene (c.224 G >C; p. Arg 75 Pro) with red blood cell UROD activity decreased by 50%. He returned to clinic 3 and 7 months after the index visit. He had stopped alcohol use, but continued smoking cigarettes. His hands were improved [Fig 1b]. Repeat urinary porphyrins showed improvement [Table 1]. The mutation in UROD is predicted to have a major effect on protein structure and function [Fig 1c]. Discussion: Inherited partial deficiency in UROD is not sufficient to cause clinically manifest PCT. Other factors that increase oxidative stress are also required. This patient has a mutation in the UROD gene not heretofore described in PCT type 2, but that we show markedly affects the structure and activity of the protein product. Nonetheless, the patient did not develop clinically manifest PCT until age 77, emphasizing the importance of acquired factors in disease pathogenesis.Figure 1.: A. Dorsal right hand at presentation B. Dorsal right hand at 7 month follow-up C. Structure of URO-D showing the substrate (yellow) in the active site located at the C-terminal end of the beta-sheets (magenta) that form the core of the TIM-barrel structure. The location of arginine 75 (Arg 75) is shown in green. Arg 75 is the penultimate residue in one of the eight corresponding alpha-helices that surround the central core. Arg 75 forms two hydrogen bonds with glutamic acid 45 (Glu 45) of the preceding helix in the structure. This hydrogen bonding network supports the overall tertiary fold of the protein in this otherwise solvent-exposed region of the protein. The UROD mutation of the patient (Arg 75 Pro) disrupts the helix with premature termination and more importantly eliminates the hydrogen bonding network.Table 1-A.: Results of Selected Laboratory Studies.Table 1-B.: Results of Selected Laboratory Studies.

Quantification and exposure assessment of microplastics in Australian indoor house dust

Limited attention has been given to the presence of MPs in the atmospheric environment, particularly in indoor environments where people spend about 90% of their time. This study quantitatively assesses the prevalence, source and type of MPs in Australian homes with the goal of evaluating human health exposure potential. Thirty-two airborne indoor deposited dust samples were collected in glass Petri dishes from Sydney (Australia) homes, over a one-month period in 2019. Participants completed a questionnaire on their household characteristics. Samples were analysed using a stereomicroscope, a fluorescent microscope and micro-Fourier transform infrared (FTIR) spectroscopy for their colour, size, shape and composition. Inhalation and ingestion rates were modelled using US EPA exposure factors. Microplastic fibre deposition rates ranged from 22 to 6169 fibres/m2/day. Deposited dust comprised 99% fibres. The highest proportion of fibres (19%) were 200–400 μm in length. The majority were natural (42%); 18% were transformed natural-based fibres; and 39% were petrochemical based. A significant difference was observed between the deposition rate and the main floor covering (p-value <0.05). Polyethylene, polyester, polyamide, polyacrylic, and polystyrene fibres were found in higher abundance in homes with carpet as the main floor covering. Where carpet was absent, polyvinyl fibres were the most dominant petrochemical fibre type, indicating the role of flooring materials (e.g. wood varnishes) in determining MP composition. Vacuum cleaner use was significantly related to MP deposition rates (p-value <0.05). MP ingestion rates peaked at 6.1 mg/kg-Bw/year for ages 1–6, falling to a minimum of 0.5 mg/kg-Bw/year in >20 years age group. Mean inhaled MP weight and count was determined to be 0.2±0.07 mg/kg-Bw/year and 12891±4472 fibres/year. Greatest inhalation intake rates were for the <0.5-yr age group, at 0.31 mg/kg-Bw/year. The study data reveal that MPs are prevalent in Australian homes and that the greatest risk of exposure resides with young children. Notwithstanding the limited number of global studies and the different methods used to measure MPs, this study indicates Australian deposition and inhalation rates are at the lower end of the exposure spectrum.

Investigation of The Effects of Heat Treatment On Varnished Wood Material

In this study, the effects of the heat treatment applied varnished wood materials on hardness, brightness and varnishes’ surface sticking resistance were investigated. For this purpose, firstly Pinus Sylvestris L., Fagus Orientalis L. and Castanea Sativa M. wooden samples were varnished by the water based varnish and after that they were kept in temperatures of 100 ˚C, 125 ˚C and 150 ˚C for times of 2, 4 and 6 hours. According to test results it was determined that while the hardness and varnishes’ surface sticking resistance were improved for all samples which were processed 2 hours in temperatures of 100 ˚C, the brightness, surface sticking resistance and brightness of the samples which were processed 4 and 6 hours in 100 ˚C and 2, 4 and 6 hours in 125 ˚C and 150 ˚C were deteriorated. Furthermore, it was observed that the hardness resistance of all samples which processed for 2, 4 and 6 hours in 100 ˚C, 125 ˚C and 150 ˚C were high. In all varnished wood species, the dual-component varnish gave better results than the single-component varnish.

Effect of Pre-Treatments On Wear Index Of Varnished Wood Plastic Composites (Wpc) With Pigmented

The utilization and usage areas of the wood plastic composites (WPC) have increased over the years. In addition, the importance of wood plastic composites produced by adding pigments has increased in terms of usage area. To be able to increase the coating ability of plastics, different pre-treatment had been used and some improvements were achieved. It is the purpose of this study to determine the wear index in abrasion of the WPC with pigmented using various coating and pre-treatments. For this purpose, it was used 2 different coating types (acrylic and cellulosic based) and 4 different pretreatments (sanding, acid treatment, UV, microwave). WPC with pigmented were manufactured and samples after various pretreatment and coating were prepared. The adhesion strength values were determined after coating. The results showed that pre-treatments used in this project affected the wear index. Acrylic based coating gave the best results of wear index in abrasion

Effect of the bleaching and varnishing process on the flame source combustion light intensity of wood material

Bu calisma, ahsap malzemede renk acma ve vernikleme isleminin alev kaynakli yanmada isik yogunluguna etkilerini belirlemek amaciyla yapilmistir. Bu maksatla, Dogu kayini (Fagus orientalis Lipsky), saricam (Pinus sylvestris Lipsky) ve Sapsiz mese (Querqus petraea Liebl.) odunlarindan ASTM D 358 esaslarina uyularak hazirlanan orneklere sodyum hidroksit (NaOH), hidrojen peroksit (H2O2), kalsiyum hidroksit (Ca(OH)2), sodyum silikat (NaSiO3), asetik asit (CH3COOH), sodyum disulfit (Na2S2O5), oksalik asit (C2H2O4) ve potasyum permanganat (KMnO4)’in % 18’lik cozeltisi ile renk acma islemi yapildiktan sonra, ASTM D3023 esaslarina gore su bazli (Sb), sentetik (Sn), poliuretan (Pu) ve akrilik (Av) vernikler uygulanmis ve isik yogunlugu ASTM E 160–50 esaslarina gore belirlenmistir. Sonuc olarak, isik yogunlugu; ahsap turu, renk acma cozeltisi ve vernik cesidi etkilesimine gore en fazla KMnO4+Na2S2O5+H2O2 (R5) ile rengi acilmis sentetik vernikli kayinda gorulurken, en az Na2S2O5+C2H2O4 (R4) ile rengi acilmis akrilik vernikli saricamda elde edilmistir. Buna gore isik yogunlugu en az olan ornekler, yanginda dumandan bogulma riskini arttirabileceklerinden uygulama alanlarinda bu durumun dikkate alinmasi onerilebilir.