Published Date 30 December 2015, Vol.101:952–957,doi:10.1016/j.conbuildmat.2015.10.152 Author
Bekir Cihad Bal a,,
İbrahim Bektaş a
Fatih Mengeloğlu a
Kadir Karakuş a
H. Ökkeş Demir b
aKahramanmaraş Sütçü İmam University, Department of Forest Industry Engineering, Faculty of Forestry, 46100 Kahramanmaraş, Turkey
bKahramanmaraş Sütçü İmam University, Department of Chemistry, Faculty of Science and Letter, 46100 Kahramanmaraş, Turkey
Received 25 May 2015. Revised 5 October 2015. Accepted 22 October 2015. Available online 10 November 2015.
Highlights
Modulus of elasticity of reinforced plywood increased significantly.
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Reinforcement decreased the inequality between parallel and perpendicular samples.
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Compared to control samples, moisture content decreased, and density increased.
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Thickness swelling and water absorption decreased for the test groups.
Abstract
The reinforcement of solid wood and wood-based composite materials is not a new idea, but there have been very few studies about reinforcing poplar plywood with glass fiber fabric using phenol formaldehyde. In this study, plywood panels were produced using poplar veneer and phenol formaldehyde adhesive and glass fiber fabric. One control group and three different test groups were set up. In addition, perpendicular and parallel test samples for each group were set up for bending tests. Some of the physical and mechanical properties of the reinforced plywood were determined using various tests. The results of the testing indicated that the plywood that was reinforced with woven glass fiber had a significantly increased modulus of rapture and modulus of elasticity of perpendicular samples. It was determined that density of the plywood was increased in the test groups. Thickness swelling and water absorption decreased for the test groups in which the plywood samples had woven glass fibers bonded onto in their surfaces. In the bending tests, the reinforcement provided by the glass fiber fabric decreased the inequalities between the parallel and perpendicular samples.
Published Date December 2015, Vol.72:90–102,doi:10.1016/j.cryogenics.2015.09.007 Author
Jeong-Hyeon Kim a
Doo-Hwan Park a
Chi-Seung Lee a
Kwang-Jun Park b
Jae-Myung Lee a,,
aDepartment of Naval Architecture and Ocean Engineering, Pusan National University, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan 609-735, Republic of Korea
bGas Technology R&D Group, Daewoo Shipbuilding & Marine Engineering, 26, Eulji-ro 5-gil, Jung-gu, Seoul 110-210, Republic of Korea
Received 28 May 2015. Revised 17 September 2015. Accepted 26 September 2015. Available online 3 October 2015. Highlights
Cryogenic mechanical properties of phenolic-resin plywood were investigated.
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Influences of cryogenic thermal loads on plywood adopted in an LNG CCS were investigated.
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Fracture patterns of phenolic-resin plywood depending on grain orientation were discussed.
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Performance degradation owing to the cryogenic thermal cycle and immersion was observed and discussed.
Abstract The main objective of the present study is to investigate the performance degradation of the plywood used in a liquefied natural gas (LNG) cargo containment system (CCS). A plywood sheet features an odd number of thinly layered wooden plies bonded perpendicularly to the previous layer to give it a very strong and durable structure. Owing to this strong point, plywood is applied to a variety of interior and exterior applications. Above all, it is widely adopted as insulation panels in an LNG CCS owing to a high stiffness with low density and its superior mechanical capabilities. As an insulation material of an LNG CCS, plywood is constantly exposed to repeated wave-induced thermal variations caused by the loading (−163 °C) and unloading (20 °C) of LNG during general operating periods of 25 years on average. Therefore, the effects of cryogenic-level thermal loads on the material characteristics of plywood must be analyzed with respect to the design and safety aspects of LNG CCSs. In the present study, the influences of the estimated thermal load, testing temperature, and grain orientation on plywood adopted in an LNG CCS are investigated. In terms of safety and design, the repeated thermal loads in a LNG CCS must be considered because the modulus of elasticity (MOE), tensile strength (TS), and modulus of rupture (MOR) are degraded by thermal treatments, such as cyclic thermal-shock and cryogenic immersion. Keywords
Published Date March 2014, Vol.49:33–37,doi:10.1016/j.ijadhadh.2013.12.011 Author
Qun Fang a,b,,
Hui-wang Cui b,c,d,e,,
Guan-ben Du b,c
aSchool of Engineering, Zhejiang A & F University, Lin’an 311300, Zhejiang, China
bSouthwest Forestry University, Kunming 650224, Yunnan, China
cCollege of Wood Science and Technology, Nanjing Forestry University, Nanjing 210037, Jiangsu, China
dDepartment of Material and Optoelectronic Science, National Sun Yat-Sen University, 804 Kaohsiung, Taiwan
eInstitute of Scientific and Industrial Research, Osaka University, Ibaraki 565-0047, Osaka, Japan
Accepted 30 September 2013. Available online 12 December 2013.
Abstract
In this study, the montmorillonite (MMT) reinforced phenol formaldehyde (PF) resin intercalated nano-composite of PF–MMT was prepared from phenol, formaldehyde, and pristine MMT. We then introduced this PF–MMT into the production of plywood from Simao Pine veneers. Matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF), wide-angle X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermal mechanical analysis (TMA), and bonding strength revealed the related structure, curing, and mechanical properties. The thermoplastic PF with a linear structure entered the MMT layers and then formed the network structure after cured. The wet bonding strength and modulus of elasticity (MOE) of plywood were improved significantly. This preparation is simple and easy, and can be applied in the production of wood industry.
