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1.
《Journal of Adhesion Science and Technology》2013,27(8):735-744
Dowel joints are widely used in furniture frame construction as a load-bearing connection structure, as well as a simple locator for parts. Joints constructed with dowels were subjected to withdrawal, bending, shear, and tensile forces. The aim of this study was to determine the withdrawal strengths of 6, 8, 10 mm diameter beech dowels embedded into matching holes drilled into the edges of medium-density fiberboard (MDF) and particleboard (PB) with solid wood edge banding of white oak with 5, 10 and 15 mm thickness, bonded with hot-melt, poly(vinyl acetate) (PVAc) and Desmodur-VTKA (D-VTKA), a polyurethane-based one-component adhesive. The effects of edge banding thickness, dowel dimension, type of composite material and type of adhesive used for edge banding on the withdrawal strength were determined. According to the interaction results from the Duncan test the highest withdrawal strength (7.019 N/mm2) was obtained in beech dowels with 6 mm diameter for MDF with solid wood edge banding of white oak with 10 mm thickness bonded with the hot-melt adhesive. Should the dowels be subjected to withdrawal, it is advised that a beech dowel should be used for MDF with solid oak edge banding with 10 mm thickness bonded with a hot-melt adhesive in furniture production and decoration applications. 相似文献
2.
Cemal Özcan Burhanettin Uysal Şeref Kurt 《Journal of Adhesion Science and Technology》2013,27(8):843-854
Composite materials and wooden dowels are being used increasingly in the construction of furniture frames and inner decoration. However, there is little information available concerning the withdrawal strength of various fasteners and in particular, dowels in these materials. The aim of this study was to determine the withdrawal strengths of 6, 8, and 10?mm diameter dowels produced from different wood species bonded parallel or vertical to the surfaces of a medium-density fiberboard (MDF) or particleboard with poly vinylacetate or Desmodur (D-VTKA). According to TS 4539 standard, the effect of dowel species, direction of withdrawal, board type and the type of adhesive on the withdrawal strength were determined. The highest (8.35?N/mm2) withdrawal strength was obtained for oak dowels bonded with D-VTKA adhesive vertically to the surface of MDF. This value is higher than the predictive expression that allows designers to estimate the withdrawal strength of dowels. 相似文献
3.
《Journal of Adhesion Science and Technology》2013,27(15):1769-1782
Laminated veneer lumbers (LVLs) manufactured from wood with different adhesives are being increasingly used in the construction of furniture frames and buildings. Yet there is little information available concerning the dimensional stability and shear strength of LVLs after being exposed to steam. In this study, LVLs were manufactured from poplar and beech veneers with phenol/formaldehyde (PF), poly(vinyl acetate) (PVAc), Desmodur-VTKA (D-VTKA) and urea/formaldehyde (UF) adhesives. Dimensional stability of LVLs was measured after being exposed to steam for 2, 6, 12, 24, 48 and 96 h, according to the Turkish Standard (TS) 3639, and also shear strength was measured (according to BS EN 205). The highest initial density of 0.93 g/cm3 was for beech LVL with VTKA adhesive. After exposure to steam for 96 h, the highest weight increase of 65.7% was for poplar LVL with PVAc, the highest radial swelling of 5.7% was for beech LVL with UF, the highest tangential swelling of 7.9% was for beech LVL with PF and the highest longitudinal swelling of 0.5% was for beech LVL with VTKA. The highest shear strength value of 15.8 N/mm2 among all samples without exposure to steam was obtained for beech LVL with PVAc adhesive and the lowest shear strength was obtained as 4.48 N/mm2 for poplar LVL with UF adhesive. 相似文献
4.
Huseyin Yorur Şeref Kurt Burhanettin Uysal 《Journal of Adhesion Science and Technology》2013,27(7):690-701
Composite materials manufactured from wood with different adhesives are being used increasingly in the construction of furniture frames and buildings. In this study, it is aimed to describe the effects of adhesives (PVAc, VTKA and UF) on white oak cut tangentially and radially impregnated with Protim WR 230, CCA, and Celcure AC 500 and exposed to humid-water-heat resistance and heating and cooling tests. Impregnation chemicals have decreased the bonding strength, and control samples gave higher bonding strength value. According to the control samples, it can be said that humid-resistance test, water-resistance test, heat-resistance test have decreased the bonding strength. As a result of the tests, white oak cut tangentially and impregnated with Protim WR 230 and bonded with VTKA adhesive can be used as a material in damp condition where the strength is required. 相似文献
5.
《Journal of Adhesion Science and Technology》2013,27(14):1681-1688
Many properties of wood are affected by changes in moisture content below the fiber saturation point of wood. In this study, the dimensional stability of laminated veneer lumber (LVL), according to TSI EN 4084 and EN 4086, was evaluated. For this purpose Scots pine (Pinus sylvestris L.) and Oriental beech (Fagus orientalis L.) LVL panels were used. Panels of LVL were manufactured from cut veneers, and poly-vinyl acetate (PVAc), unsaturated polyester (uPE) and mixtures of them, as adhesives. Laminated veneer lumber panels with 4 plies and 5 mm in thickness were produced for each group. Depending on the adhesive type, the swelling and water absorption of the samples were measured by determining the weight increase in the two conditions of oven dried and being above the fiber saturation point. The lowest volumetric swelling of the Scots pine was measured as 10.4% bonded with 100% PVAc (control) and the highest volumetric swelling was measured as 13.8% bonded with 90% PVAc and 10% unsaturated polyester. The lowest volumetric swelling of the Oriental beech was measured as 17.2% bonded with 100% PVAc (control) and the highest volumetric swelling was found to be 21.8% bonded with 90% PVAc and 10% unsaturated polyester. Statistical analysis results show that adding unsaturated polyester to the PVAc increased the volumetric swelling and water absorption levels of both the Scots pine and Oriental beech LVL panels. 相似文献
6.
A new corn starch adhesive modified by starch‐g‐polyvinyl acetate (starch‐g‐PVAc) and epoxy resin is described in this study. Starch‐g‐PVAc is used as high cohesive energy component to improve the dry shear strength of the starch adhesive. Although the epoxy resin, which can easily crosslink with the oxidized starch, is used as water‐resistant component to improve the wet shear strength. Because there is no chemical reaction happening between polyvinyl acetate and epoxy resin, both the dry shear strength and the wet shear strength of the corn starch adhesive are notably increased. Considering all the related factors, the optimum of the modification is achieved when the dosage of starch‐g‐PVAc and epoxy resin is 70% of the oxidized starch latex with m(Ep): m(starch‐g‐PVAc) = 1:2. That is, the epoxy resin is 23% in mass fraction and starch‐g‐PVAc 47% in mass fraction. The dry shear strength is 4.50 MPa, and the wet shear strength is 2.51 MPa. The modified corn starch has a broad prospect in the application of plywood industry. POLYM. COMPOS., 2013. © 2012 Society of Plastics Engineers 相似文献
7.
《Journal of Adhesion Science and Technology》2013,27(3-4):319-330
The selection of the most appropriate surfacing technique is influential in the success of bonding, painting and varnishing processes. The objective of the study was to determine which surfacing technique was the most appropriate when applied as the final process in the production of structural wood members, which were subjected to shearing. The study also includes the effect on shear strength of the variables, such as type of wood, plane of cut, type of adhesive and pressing pressure, as they are directly related to the main objective of the study. In view of this objective, the changes in shear strength on radial and tangential cut surfaces of Oriental beech (Fagus orientalis Lipsky) and Scotch pine (Pinus sylvestris L.) woods having different roughness values as a result of sawing with a circular ripsaw, planing and sanding, and bonded with polyurethane (PU) and poly(vinyl acetate) (PVAc) adhesives at 3, 6 and 9 MPa pressure, were studied. The 936 specimens prepared with the objective of determining the effects of variables on bond performance were subjected to a shear test in a universal test equipment in accordance with the ASTM D 905-98 standard. The highest shear strength (13.85 N/mm2) was obtained for the Oriental beech specimens cut from their tangential surfaces with a circular ripsaw, which were glued with PVAc adhesive by applying a pressure of 9 MPa. The lowest value (4.22 N/mm2) was obtained in the specimens planed from their tangential surfaces, which were glued with PU adhesive by applying a pressure of 3 MPa. The specimens obtained from Oriental beech wood showed a higher shear strength compared to the specimens obtained from Scotch pine. In general, in both species of wood, the specimens glued with PVAc adhesive, both on the tangential surfaces and on the radial surfaces, produced higher shear strengths compared to the specimens glued with PU adhesive. 相似文献
8.
Combination of lignin polyol–tannin adhesives and polyethylenimine for the preparation of green water‐resistant adhesives
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Abbas Hasan Faris Afidah Abdul Rahim Mohamad Nasir Mohamad Ibrahim Adel Mustafa Alkurdi Irfan Shah 《应用聚合物科学杂志》2016,133(20)
In this study, a green adhesive from renewable lignin and tannin was developed with polyethylenimine (PEI) with a method to improve the water resistance of the lignin/tannin adhesive. Lignin polyols were prepared through the liquefaction of oil‐palm empty fruit bunches. The characteristics of the adhesive samples were compared with those of a commercial phenol–formaldehyde resin. Three plywood specimens bonded with the new adhesive showed a very high tensile strength (63.04 MPa) and were very water resistant. The effect of the solid content of the adhesives on the tensile strength and gel time and various weight ratios of PEI on the tensile strength and water resistance of the plywood specimens were evaluated. Thermal stability tests revealed that the lignin polyol–tannin/PEI adhesives had a high heat resistance (360 °C). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43437. 相似文献
9.
In this study, the change in shear strength on radial and tangential surfaces of Calabrian Pine (Pinus brutia Ten.) wood having different roughness values as the result of sawing with a circular ripsaw, planing and sanding, and bonded with polyurethane (PU) and polyvinyl acetate (PVAc) adhesives at the pressure levels of 3, 6, and 9 kgf/cm2, was studied. Each of the 360 specimens prepared to determine the effect of the variables on bond performance were subjected to shear test in an universal test machine in accordance with the ASTM D 905–98 standards. The values obtained were analyzed statistically and the results were interpreted. The highest shear strength (11.83 N/mm2) for plane of cut was obtained on the tangential surface after sanding and applying PVAc adhesive with a pressing pressure of 9 kgf/cm2. The lowest shear strength (6.01 N/mm2) was obtained in the joinings made on the planed surfaces by using PU adhesive and a pressing pressure of 3 kgf/cm2. The highest shear strength (9.10 N/mm2) on the radial surface was obtained after sanding and applying PVAc adhesive and pressing with a pressure of 6 kgf/cm2. The lowest shear strength (3.76 N/mm2) was obtained in the specimens whose surfaces were sanded and glued with PU adhesive with a pressing pressure of 3 kgf/cm2. In general, in the radial surfaces, just like in the tangential surfaces, the specimens bonded with PVAc exhibited a higher shear strength compared with those glued with PU. According to these results, it is definitely necessary to sand the surfaces prior to the bonding process to have a higher shear strength. The bonding process should be made on the tangential surfaces with higher pressures. The PVAc adhesive should be preferred instead of the PU adhesive. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3050–3061, 2006 相似文献
10.
In this study, we aimed to describe the effects of adhesives [poly(vinyl acetate) (PVAc), Desmodur vinyl trie ketonol acetate, and urea formaldehyde (UF)] on wooden materials (Scotch pine and oriental beech) cut tangentially and radially impregnated with Protim Solignum, chromate copper arsenate (CCA), and Celcure AC 500 and exposed to humidity and water and heat‐resistance, heating, and cooling tests. For the adhesives, the highest swelling (4.3%) was obtained for oriental beech bonded with UF and cut radially, and the lowest swelling (1%) was obtained for Scotch pine bonded with PVAc and cut radially. For the control samples, the humidity‐resistance, water‐resistance, heat‐resistance, and heating and cooling tests decreased the bonding strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
11.
Marzieh Gangi Taghi Tabarsa Sima Sepahvand 《Journal of Adhesion Science and Technology》2013,27(13):1407-1417
The aim of this work is to evaluate performances of tannin-based resins designed as adhesive in the plywood production. For this purpose, a part of phenol formaldehyde (PF) and melamine formaldehyde (MF) in the classic adhesive formulation was replaced by tannin. The physical properties of the formulated resins (rheological characterization, etc.) were measured. In order to analyze the mechanical performance of tannin-based resins, plywood panels were produced and the mechanical properties including tensile strength wood failure and three-point bending strength were investigated. The performance of these panels is comparable to those of plywood panels made by commercial PF and MF. The results showed that the plywood panels bonded with tannin–PF (PFT) and tannin–MF (MFT) resins exhibited better mechanical properties in comparison to the plywood panels made of commercials PF and MF. The introduction of small properties of tannin in PF and MF resins contribute to the improvement of the water performance of these adhesives. The formaldehyde emission levels obtained from panels bonded with tannin-based resins were lower than those obtained from panels bonded with control PF and MF. Although there are no actual reaction at all between PF, MF, and tannin, addition of tannin significantly improves the water resistance of PF and MF resins. This is a novel finding that manifests the possibility of replacing a convention PF and MF resins by tannin. Modified adhesive is one of the goals in the plywood production without changing any of their production conditions with improvement to their overall properties. 相似文献
12.
In this study, the change in shear strength on radial and tangential surfaces of Calabrian pine (Pinus brutia Ten.) wood having different roughness values as the result of sawing with a circular ripsaw, planning, and sanding, and bonded with polyurethane (PU) and polyvinyl acetate (PVAc) adhesives at the pressure levels of 3, 6, and 9 kg f/cm2 were studied. A total of 360 specimens of each, prepared with the objective of being able to determine the effect of the variables on bond performance, were subjected to the shear test in the universal test machine in accordance with the ASTM D 905–98 standard. The values obtained were analyzed statistically and the results were interpreted. The highest shear strength (11.83 N/mm2) for plane of cut was obtained on the tangential surface after sanding and applying PVAc adhesive with a pressing pressure of 9 kg f/cm2. The lowest shear strength (6.01 N/mm2) was obtained in the joinings made on the planed surfaces by using PU adhesive and a pressing pressure of 3 kg f/cm2. The highest shear strength (9.10 N/mm2) on the radial surface was obtained after sanding and applying PVAc adhesive and pressing with a pressure of 6 kg f/cm2. The lowest shear strength (3.76 N/mm2) was obtained in the specimens whose surfaces were sanded and by using PU adhesive and with a pressing pressure of 3 kg f/cm2. In general, in the radial surfaces, just like in the tangential surfaces, the specimens bonded with PVAc produced a higher shear strength compared to those glued with PU. According to these results, it is definitely necessary to sand the surfaces prior to the bonding process to have a higher shear strength. The bonding process should be made on the tangential surfaces with higher pressures. The PVAc adhesive should be preferred instead of the PU adhesive. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4856–4867, 2006 相似文献
13.
Urea–formaldehyde (UF) adhesive mixtures with a 5% suspension of microfibrillated cellulose (MFC) at 0.5, 1, 3, and 5 wt% loading levels based on the solid weight (62.4%) of the UF adhesive were prepared. Beech lamellas with dimensions of 5 mm×20 mm×150 mm were prepared from beech lumbers using a planer saw. The UF adhesive (E0 class) was mixed with the MFC using a magnetic stirrer to achieve a proper distribution of the MFC in the UF adhesive. The tensile shear strength of single lap-joint specimens bonded with UF adhesive containing MFC was determined in accordance with EN 205 (2003). The specimens bonded with UF adhesive containing the MFC showed better tensile shear strengths as compared to the control. As compared to the control specimens, the tensile shear strength of the specimens increased by 5.7% as 3 wt% of the MFC was incorporated into the UF adhesive. However, a further increment in the MFC content up to 5 wt% decreased the tensile shear strength of the specimens (−14.3% of control specimen). The MFCs were well dispersed in the UF resin and were cross-linked to form a network to reinforce the bond line, improving bonding performance. 相似文献
14.
In this study, we developed a formaldehyde-free adhesive from abundant, renewable, and inexpensive soy flour (SF). The main
ingredients of this adhesive included SF, polyethylenimine (PEI), and maleic anhydride (MA). The optimum formulation of this
adhesive and the optimum hot-press conditions for making plywood were investigated. A three-cycle soak test and a boiling
water test (BWT) were employed for evaluating the strength and water-resistance of plywood bonded with this adhesive. Results
showed that SF, PEI, MA and sodium hydroxide were all essential components for the adhesive and the SF/PEI/MA weight ratio
of 7/1.0/0.32 resulted in the highest water-resistance. When the hot-press temperature was in the range of 140–170 °C, both
water-resistance and shear strength of plywood bonded with the adhesive remained statistically the same, except that the dry
shear strength of plywood at 170 °C was statistically lower than that at 160 °C. When the hot-press time ranged from 2 to
6 min, the plywood panels at 5 min had the highest boiling water test/wet (BWT/w) shear strength. The plywood panels made
at 5 min had a higher dry shear strength than those made at 3 min. Plywood panels bonded with this SF/PEI/MA adhesive exceeded
the requirements for interior applications. 相似文献
15.
Zhen-wen Zhang Rui Liu Jia-liang Zhang 《Journal of Adhesion Science and Technology》2018,32(7):721-738
Bamboo–steel composite structure is a newly developed structure, composed of bamboo plywood and cold-formed thin-walled steel bonded by structural adhesive. This paper configured a three-dimensional (3D) numerical model to characterize the progressive failure of bamboo–steel adhesive bonding interface subjected low-energy impact and tension in sequence. A 3D cohesive zone model (CZM) with reloading trapezoid softening law was adopted to characterize the debonding behavior of the bamboo–steel interface. Investigations on the debonding damage propagation of the bamboo–steel interface subjected low-energy impact and tension after impact were completed, and the influence factors of the residual tensile strength were studied. 相似文献
16.
17.
Qiang Gao Sheldon Q. Shi Shifeng Zhang Jianzhang Li Xiaomei Wang Wubin Ding Kaiwen Liang Jinwu Wang 《应用聚合物科学杂志》2012,125(5):3676-3681
Soybean meal flour, polyethylene glycol (PEG), sodium hydroxide (NaOH), and a melamine-urea-formaldehyde (MUF) resin were used to formulate soybean meal/MUF resin adhesive. Effects of the adhesive components on the water resistance and formaldehyde emission were measured on three-ply plywood. The viscosity and solid content of the different adhesive formulations were measured. The functional groups of the cured adhesives were evaluated. The results showed that the wet shear strength of plywood bonded by soybean meal/NaOH adhesive increased by 33% to 0.61 MPa after adding NaOH into the adhesive formulation. Addition of PEG reduced the viscosity of the soybean meal/NaOH/PEG adhesive by 91% to 34,489 cP. By using the MUF resin, the solid content of the soybean meal/MUF resin adhesive was improved to 39.2%, the viscosity of the adhesive was further reduced by 37% to 21,727 cP, and the wet shear strength of plywood bonded by the adhesive was increased to 0.95 MPa, which met the interior plywood requirements (≥0.7 MPa). The formaldehyde emission of plywood bonded by the soybean meal/MUF resin adhesive was obtained at 0.28 mg/L, which met the strictest requirement of the China National Standard (≤0.5 mg/L). FTIR showed using the MUF resin formed more CH2 group in the cured adhesive. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
18.
《Journal of Adhesion Science and Technology》2013,27(9):949-969
The aim of this study, is to describe the effects of adhesives (PVAc-Desmodur VTKA and Urea formaldehyde) on wooden materials (walnut and poplar) cut tangentially and radially impregnated with Protim Solignum, CCA and Celcure AC 500 and exposed to: humid–water–heat resistance; heating; and cooling tests. All these tests show a decreased in bonding strength. The conclusion is that poplar wood cut tangentially and impregnated with CCA, bonded with D-VTKA adhesive can be used as a material in damp conditions where good bond strength is required. 相似文献
19.
Burhanettin Uysal 《Journal of Adhesion Science and Technology》2013,27(8):896-904
In wood materials, the species of wood, its humidity, and the type of the adhesive have an important role to make the wood material durable for a long period both in inner space and outer space. In this study, it is aimed to determine the resistance characteristics of adhesive using different impregnation chemicals and different types of adhesives before and after steam treatment. In this study, beech and poplar as wood materials; mixture of Protim-WR 235, Tanalith-C, and Celcure-AC 500 as impregnation materials; and poly vinyl acetate (PVAc), urea formaldehyde (UF), and desmodur vinyl trie ketonol acetate (D-VTKA), resistant to water, as adhesives materials were used. All samples were kept in a steaming equipment for 2, 6, 12, 24, 48, and 96?h, afterwards the maximum force of the samples were measured for each waiting period, and then their bonding strength was determined. According to the results of the study, beech control samples had higher strength than poplar control samples. Control samples bonded with D-VTKA is the least affected one compared to all original control samples in the steam test. D-VTKA can be offered as the proper adhesive for humid places. The results also showed that Tanalith-C is the least affecting impregnation material on the bonding strength. 相似文献
20.
Mehrdad Azamian Jazi Ahmad Ramezani S.A. Seyyed Arash Haddadi Saeed Ghaderi Fariba Azamian 《应用聚合物科学杂志》2020,137(15):48570
Polyvinyl acetate (PVAc) nanocomposites for wood adhesives containing different amounts of colloidal silica nanoparticles (CSNs) were synthesized via in situ one-step emulsion polymerization. The adhesion strength of wood specimens bonded by PVAc nanocomposites was investigated by the tensile test. Thermal properties of PVAc nanocomposites were also characterized by differential scanning calorimetry and thermogravimetric analysis. Rheological and morphological properties of the PVAc nanocomposites were investigated using rheometric mechanical spectrometry and field emission scanning electron microscopy (FESEM), respectively. The obtaining results showed that the shear strength of PVAc nanocomposite including 1 wt. % CSNs has the highest shear and tensile strength about 4.7 and 3.2 MPa, respectively. A small increment of Tg (~3 °C) and considerable increment of the ash content proved the enhancement of PVAc thermal characterization in the presence of CSNs. FESEM results showed uniform dispersion of nanoparticles throughout the PVAc matrix due to using the in situ emulsion polymerization process. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48570. 相似文献