Some mechanical properties and decay resistance of wood impregnated with environmentally-friendly borates

This study was made to determine some mechanical properties such as compression strength parallel to grain, modulus of rupture, and decay resistance of wood treated with some environmentally-friendly borates. Sodium tetrafluoroborate (SFB), ammonium tetrafluoroborate, (AFB), and ammonium pentaborate octahydrate (APB) were used as borates. Wood specimens were prepared from Oriental beech (Fagus orientalis L) and Scots pine (Pin us sylvestris L.). Before tests, wood specimens were impregnated with aqueous solutions (0.25%, 0.50%, 1.50%, and 3.00%) of borates according to ASTM D 1413-76. Results showed that compression strength parallel to grain (CSPG) and modulus of rupture (MOR) of wood specimens treated with borates were lower compared to untreated control specimen. In general, our results showed that the higher concentration levels of borates, the lower mechanical properties of wood resulted. Borate treated wood showed considerable resistance to the decay fungus compared to that of untreated control specimen. (C) 2010 Elsevier Ltd. All rights reserved

Physical, mechanical, and thermal characteristics of alkaline copper quaternary impregnated oriental beech wood

The physical, mechanical, and thermal properties of Oriental beech (Fagus orientalis), which had been impregnated with the water-based, copper-containing Korasit KS material from the Alkaline Copper Quaternary group, were investigated in this study. According to ASTM 1413-07el (2007) standard, the wood samples used in the investigation were impregnated with 3 % and 6 % aqueous solutions of Korasit KS. The modulus of rupture, thermal, and water absorption tests were performed on samples of Oriental beech after they had been impregnated. Oriental beech's modulus of rupture values decreased as a result of Korasit KS impregnation. Additionally, Oriental beech had lower modulus of rupture values at greater concentrations of Korasit KS. In every water absorption period, the water absorption values of the Oriental beech impregnated with Korasit KS were higher than those of the control group. Our results showed that Korasit KS impregnation enhanced thermal properties of Oriental beech. Moreover, higher concentration levels of Oriental beech yielded better thermal characteristics of Oriental beech

Some surface characterıstıcs of orıental beech wood ımpregnated wıth some fıre-retardants and coated wıth polyurea/polyurethane hybrıd and epoxy resıns

This study was made to determine surface characteristics such as colour, gloss, and surface hardness changes of Oriental beech (Fagus orientalis). The wood specimens were firstly impregnated with some fire-retardants (FRs) and primed with epoxy resin (EPR) and then coated with polyurethane/polyurea hybrid resin (PUU). Oriental beech was impregnated with 3 % aqueous solution of boric acid (BA), borax (BX), boric acid and borax mixture (1:1), and ammonium sulphate (AS). While Sikafloor®-156 was used for epoxy coating (EPR), Sikalastic®-851 R was used for polyurethane/polyurea hybrid coating (PUU). According to our results, all treatment groups gave negative lightness stability values after accelerated weathering. The colour stability of epoxy resin coated Oriental beech was higher than that of polyurethane/polyurea hybrid resin coated Oriental beech. Except for boric acid impregnated and polyurethane/polyurea hybrid resin coated Oriental beech, all fire-retardants treatment before polyurethane/polyurea hybrid resin and epoxy resin coatings decreased the gloss losses of Oriental beech after accelerated weathering. Fire-retardants impregnation before epoxy resin and polyurethane/polyurea hybrid resin coatings improved the surface hardness values of Oriental beech after accelerated weathering

Mechanıcal and fıre propertıes of orıental beech ımpregnated wıth fıre-retardants and coated wıth polyurea/polyurethane hybrıd and epoxy resıns

This study was performed to investigate some mechanical properties such as modulus of rupture and compression strength parallel to grain and some fire properties such as weight loss and temperature values of Oriental beech (Fagus orientalis) treated with fire-retardants  and coated with polyurethane/polyurea hybrid resin and epoxy resin were investigated. The coatings are based on epoxy and polyurethane\polyurea hybrid resins. Firstly,  an impregnation method was applied by using fire-retardants which are boron chemicals and ammonium sulfate before coating process. Oriental beech was impregnated with 3 % aqueous solution of boric acid, borax, boric acid and borax mixture (1:1), and ammonium sulfate. Oriental beech was primed with epoxy resin by using Sikafloor®-156, and then coated with Sikalastic®-851, a polyurethane/polyurea hybrid resin. Results showed that modulus of rupture and compression strength parallel to grain values of polyurethane/polyurea and epoxy resin coated Oriental beech wood were higher than that of un-treated and non-coated (control) group. Fire-retardants treatment before polyurethane/polyurea and epoxy resin coatings caused to decrease modulus of rupture and compression strength parallel to grain values of Oriental beech in some extent. Weight loss and temprature  values of polyurethane/polyurea and epoxy resin coated Oriental beech were higher than that of un-treated and non-coated (control) group. Hovewer, fire-retardants treatment before polyurethane/polyurea and epoxy resin coatings improved fire properties of Oriental beech wood

Synthesis of mesoporous MCM-41 materials with low power microwave heating

Crystalline, high surface area, hexagonal mesoporous MCM-41 having uniform pore sizes and good thermal stability was successfully synthesized at 90-120oC in 30 minutes using low power microwave irradiation. This appears to be the first comprehensive and quantitative investigation of the comparatively rapid synthesis of mesoporous MCM-41 using low power microwave heating of 80W (90oC) and 120W (120oC). The influence of reaction temperature and the duration of heating were carefully investigated and the calcined MCM-41 materials were characterized by XRD, SEM, TEM, nitrogen adsorption, TGA and FTIR. The mesoporous MCM-41 product synthesized in 30 minutes at 120W and calcined at 550oC had a very high surface area of 1438 m2/g and was highly ordered, contained uniform pores with diameters in the range of 3.5-4.5 nm. The wall thickness of the materials highly depended on the power of the microwave energy used during the synthesis. Synthesis of the mesoporous MCM-41 products at 120oC resulted with a structure having thinner walls. The mesoporous MCM-41 materials synthesized in the present work had good thermal stability

Surface characteristics of oriental beech and scots pine woods heat-treated above 200 degrees C

Heat-treated of Oriental beech (Fagus orientalis L.) and Scots pine (Pinus sylvestris L.) woods were carried out by hot air in an oven for 1, 3, and 5 hours at 205, 220, and 235 degrees C. After heat treatments, some surface properties such as color and gloss changes of both wood specimens were evaluated. Our results showed that heat treatment caused decrease in gloss values of Oriental beech and Scots pine wood specimens. Higher treatment temperature and duration resulted in higher gloss loss of wood specimens after heat treatments. Heat-treated wood became darker tonality, especially; it became more darkening after 3 and 5 hours heat treatments. Generally according to our results, Delta a* and Delta a* decreased after heat treatments. Oriental beech wood tended to become less reddish than Scots pine after heat treatments. Delta a*, Delta b* and Delta E* of heat-treated Oriental beech and Scots pine decreased with increasing treatment temperature and duration

Thermal characteristics of oriental beech wood treated with some leaching resistant borates

It was aimed to investigate thermogravimetric analysis (TGA), differential-thermogravimetric (DTG), and differential-thermal analysis (DTA) of Oriental beech (Fagus orientalis L.) wood treated with some leaching resistant borates such as sodium tetraphenylborate (STPB) and phenylboronic acid (PBA). In this study; 0.25, 1.00, and 4.70 % aqueous solutions of borates were prepared. Results of the study indicated that pyrolysis occurred in three stages for STPB and PBA treated Oriental beech wood. Generally, while concentrations of the STPB and PBA increased, Ti and Tmax values of STPB and PBA treated wood specimens decreased. Residual char contents of STPB and PBA treated wood specimens for all concentrations were higher than untreated control specimen

Surface characteristics of scots pine wood heated at high temperatures after weathering

This study was conducted to investigate some surface properties of wood specimens of heat treated Scots pine (Pinus sylvestris L.) after weathering such as surface hardness, surface roughness, gloss, and color changes. Heat treatment of Scots pine wood was carried out by hot air in an oven for 1, 2, and 3 hours at 210, 220, and 230°C. The results showed that generally surface hardness losses of heat treated Scots pine wood were lower than that of un-heated Scots pine wood after weathering. Heat treated Scots pine wood gave smooth surface after weathering. Except for heat treatment at 230°C for 1 and 2 hours, heat treatment resulted in better glossiness compared to un-heated Scots pine wood after weathering. According to the test results, while heat treated Scots pine wood become lighter after weathering, un-heated wood become darken after weathering. In general, heat treated wood surface to become reddish and yellowish after weathering.No sponso

Surface characteristics of scots pine treated with chemicals containing some copper compounds after weathering

In this study, it was aimed to investigate surface hardness, gloss, and color changes of Scots pine treated with chemicals containing some copper compounds after six months weathering. Adolit KD-5 (AD KD-5), celcure AC-500 (CAC-500), and wolmanit CX-8 (WCX-8) were used as impregnation chemicals containing copper compounds. Scots pine wood specimens were treated with 2 % aqueous solution of chemicals according to ASTM D1413-07e1 (2007) standard. Results showed that while surface hardness and gloss values of untreated Scots pine wood specimens were decreased after weathering, they increased treated Scots pine wood specimens after weathering. The decrease in L* of untreated and treated wood indicates that the specimens became darker after weathering. While weathering caused less green and less yellow for untreated control specimen, it caused less red and less yellow for treated wood. Treated Scots pine wood specimens showed better color stability compared to untreated Scots pine after weathering. In terms of surface hardness, gloss, and color stability values CAC-500 treated Scots pine gave the best results after weathering

Poboljšanje otpornosti drva na vremenske utjecaje impregnacijom boratima i premazom od tekućeg stakla

Poor weathering performance of impregnated and coated wood products is an important issue that infl uences their appearance as well as their service life after outdoor or indoor exposure. A novel procedure to improve the weathering performance of Scots pine wood (Pinus sylvestris L.) is proposed in this study. Wood samples were impregnated with ammonium tetrafl uoroborate (ATFB), ammonium pentaborate (APB) and boric acid (BA), and afterward coated with a layer of liquid glass (LG). Surface hardness, color changes, and surface roughness of wood samples were investigated after 250 h and 500 h of exposure to artifi cial weathering. The results revealed that, except for untreated (control), all other treatment groups caused an increase in surface hardness of Scots pine after weathering. A decrease in the CIE L* value corresponds to the darkening of samples after weathering. Borates-impregnated and LG-coated Scots pine samples possessed the highest color stability. However, all treatment combinations resulted in reddish and yellowish tones after weathering. Exposure to weathering increased surface roughness of wood samples. The surface roughness of the untreated (control) group was higher than that of impregnated and coated samples.Slaba otpornost impregniranoga i premazanog drva pri izlaganju vremenskim utjecajima velik je problem koji utječe na izgled i vijek trajanja drva nakon izlaganja u eksterijeru ili interijeru. U ovom je istraživanju predložen novi postupak poboljšanja otpornosti borovine (Pinus sylvestris L.) izložene vremenskim utjecajima. Uzorci drva impregnirani su amonijevim tetrafl uoroboratom (ATFB), amonijevim pentaboratom (APB) i bornom kiselinom (BA), nakon čega su premazani tekućim staklom (LG). Ispitivana je tvrdoća površine, promjena boje i hrapavost površine uzoraka drva nakon 250 i 500 sati umjetnog izlaganja vremenskim utjecajima. Rezultati su pokazali da se na svim površinski obrađenim uzorcima borovine povećala tvrdoća njezine površine nakon izlaganja vremenskim utjecajima. Smanjenje vrijednosti CIE L* upućuje na tamnjenje uzoraka nakon izlaganja vremenskim utjecajima. Najbolju stabilnost boje pokazali su uzorci borovine impregnirani boratima i premazani tekućim staklom. Međutim, sve kombinacije površinske obrade rezultirale su povećanjem crvenoga i žutog tona nakon izlaganja uzoraka vremenskim utjecajima. Izlaganjem vremenskim utjecajima povećala se hrapavost površine uzoraka drva. No hrapavost površine kontrolnih uzoraka (površinski neobrađenih) bila je veća nego hrapavost površine impregniranih i premazanih uzoraka.No sponso