scholarly journals Comparison of Multilayer Transparent Wood and Single Layer Transparent Wood With the Same Thickness

2021 ◽  
Vol 8 ◽  
Author(s):  
Yan Wu ◽  
Yajing Wang ◽  
Feng Yang

In this paper, poplar was used as raw material, sodium chlorite was used to delignify it in acidic environment, and then epoxy resin was vacuum impregnated in the delignified wood template to prepare transparent wood. Moreover, in order to imitate the lamination method of plywood, the multilayer transparent wood was prepared by means of staggered vertical lamination. The purpose of this paper is to study the physical and chemical properties of multilayer transparent wood, and to explore the application potential of multilayer transparent wood as a new material by comparing with single layer transparent wood with the same thickness. The weight of wood components in the transparent wood prepared in this experiment accounts for about 30–45% of the weight of composite materials. Scanning electron microscopy (SEM) measurements, Fourier transform attenuated total reflection infrared spectroscopy (ATR-FTIR) characterization, weight gain measurements, UV transmittance measurements, color difference measurements, water contact angle measurements and mechanical properties measurements were used to study. The results showed that as the thickness of the transparent wood increased, the cracks between the resin and the wood cell wall increased, and the interface showed an uneven state. In the case of the same thickness, the multilayer transparent wood was made by laminating transparent wood sheets, with fewer internal cracks and smooth interfaces. Its light transmittance is better than single layer transparent wood. Moreover, compared with single layer transparent wood with the same thickness, the lightness of multilayer transparent wood decreased, and tended to yellow and red. Due to the removal of lignin, the tensile strength of transparent wood decreased during the preparation process. However, it can be seen from the mechanical strength test that the tensile strength of multilayer transparent wood is much higher than that of single layer transparent wood. To a certain extent, multilayer transparent wood can improve the mechanical strength of transparent wood. To conclude, multilayer transparent wood is a kind of natural transparent material with large thickness, good light transmission and excellent mechanical properties, and it has a good development prospect.

1997 ◽  
Vol 12 (4) ◽  
pp. 1091-1101 ◽  
Author(s):  
Seunggu Kang ◽  
Hongy Lin ◽  
Delbert E. Day ◽  
James O. Stoffer

The dependence of the optical and mechanical properties of optically transparent polymethyl methacrylate (PMMA) composites on the annealing temperature of BK10 glass fibers was investigated. Annealing was used to modify the refractive index (R.I.) of the glass fiber so that it would more closely match that of PMMA. Annealing increased the refractive index of the fibers and narrowed the distribution of refractive index of the fibers, but lowered their mechanical strength so the mechanical properties of composites reinforced with annealed fibers were not as good as for composites containing as-pulled (chilled) glass fibers. The refractive index of as-pulled 17.1 μm diameter fibers (R.I. = 1.4907) increased to 1.4918 and 1.4948 after annealing at 350 °C to 500 °C for 1 h or 0.5 h, respectively. The refractive index of glass fibers annealed at 400 °C/1 h best matched that of PMMA at 589.3 nm and 25 °C, so the composite reinforced with those fibers had the highest optical transmission. Because annealed glass fibers had a more uniform refractive index than unannealed fibers, the composites made with annealed fibers had a higher optical transmission. The mechanical strength of annealed fiber/PMMA composites decreased as the fiber annealing temperature increased. A composite containing fibers annealed at 450 °C/1 h had a tensile strength 26% lower than that of a composite made with as-pulled fibers, but 73% higher than that for unreinforced PMMA. This decrease was avoided by treating annealed fibers with HF. Composites made with annealed and HF (10 vol. %)-treated (for 30 s) glass fibers had a tensile strength (∼200 MPa) equivalent to that of the composites made with as-pulled fibers. However, as the treatment time in HF increased, the tensile strength of the composites decreased because of a significant reduction in diameter of the glass fiber which reduced the volume percent fiber in the composite.


2015 ◽  
Vol 749 ◽  
pp. 278-281
Author(s):  
Jia Horng Lin ◽  
Jing Chzi Hsieh ◽  
Jin Mao Chen ◽  
Wen Hao Hsing ◽  
Hsueh Jen Tan ◽  
...  

Geotextiles are made of polymers, and their conjunction with different processes and materials can provide geotextiles with desirable characteristics and functions, such as filtration, separation, and drainage, and thereby meets the environmental requirements. Chemical resistant and mechanical strong polymers, including polyester (PET) and polypropylene (PP), are thus used to prolong the service life of the products made by such materials. This study proposes highly air permeable geotextiles that are made with different thicknesses and various needle punching speeds, and the influences of these two variables over the pore structure and mechanical properties are then examined. PET fibers, PP fibers, and recycled Kevlar fibers are blended, followed by being needle punched with differing spaces and speeds to form geotextiles with various thicknesses and porosities. The textiles are then evaluated for their mechanical strength and porosity. The test results show that a thickness of 4.5 cm and 1.5 cm demonstrate an influence on the tensile strength of the geotextiles, which is ascribed to the webs that are incompletely needle punched. However, the excessive needle punching speed corresponding to a thickness of 0.2 cm results in a decrease in tensile strength, but there is also an increase in the porosity of the geotextiles.


2019 ◽  
Vol 54 (10) ◽  
pp. 1259-1271 ◽  
Author(s):  
Medhat Elwan ◽  
A Fathy ◽  
A Wagih ◽  
A R S Essa ◽  
A Abu-Oqail ◽  
...  

In the present study, the aluminum (Al) 1050–FeTiO3 composite was fabricated through accumulative roll bonding process, and the resultant mechanical properties were evaluated at different deformation cycles at ambient temperature. The effect of the addition of FeTiO3 particle on the microstructural evolution and mechanical properties of the composite during accumulative roll bonding was investigated. The Al–2, 4, and 8 vol.% FeTiO3 composites were produced by accumulative roll bonding at room temperature. The results showed improvement in the dispersions of the particles with the increase in the number of the rolling cycles. In order to study the mechanical properties, tensile and hardness tests were applied. It was observed that hardness and tensile strength improve with increasing accumulative roll bonding cycles. The microhardness and tensile strength of the final composites are significantly improved as compared to those of original raw material Al 1050 and increase with increasing volume fraction of FeTiO3, reaching a maximum of ∼75 HV and ∼169 MPa for Al–8 vol.% FeTiO3 at seventh cycle, respectively.


2016 ◽  
Vol 833 ◽  
pp. 3-10
Author(s):  
Tay Chen Chiang ◽  
Sinin Hamdan ◽  
Mohd Shahril Osman

Every year, the sago processing industry in Sarawak-Mukah had generated huge amount of sago waste after the milling process and scientists have employ the waste into composite material. The fabrication and testing method are based on the Japanese A5908 Industrial Standard. Single-layer particleboards with targeted density of 600kg/m3 were produced from different sizes of sago particles. The mechanical properties of sago waste were investigated to study the feasibility of using this sample as a raw material in particleboard manufacturing. The results of the test demonstrate that samples with different sizes of particles have great influence on the mechanical properties such as Young’s Modulus, Tensile Strength and Impact Strength. The findings show that the performance of the board is affected by the different sizes of sago particles used in the experiment and had proved that sago plants can be used as an alternative raw material in the particleboard manufacturing industry.


2016 ◽  
Vol 842 ◽  
pp. 43-52 ◽  
Author(s):  
Viktor Malau ◽  
Latif Arifudin

Vickers microindentation hardness test has been applied for a long time to determine the mechanical properties of a small volume of samples. The procedure of this hardness test consists of using a constant load on a rigid indenter and measuring the dimensions of the indenter residual impression (indentation imprint) on the surface of the sample tested after loading and unloading. The objective of this research is to characterize the mechanical properties and material constants of HQ (High Quality) 705 alloy steel mainly its VHN (Vickers Hardness Number) and tensile strength before and after quenching and tempering heat treatments. The characterization is based on Vickers microhardness dependence load curves.Quenching treatment was performed in a furnace by heating the samples at austenite temperature of 850 o C with holding time of two hours and then the samples were rapidly cooled in oil bath. Tempering processes were conducted by heating again the quenching samples to temperatures of 150, 200, 250, 300, 350, 400, 450, 500, 550 and 600 o C with holding time of two hours for each sample. Finally, all samples were slowly cooled in atmospheric temperature. The mechanical properties of samples were characterized by using Vickers microhardness dependence load curves.The results show that VHN (Vickers Hardness Number) depends on indentation load and VHN increases with increment of load for indentation load lower than 5 N. VHN is almost constant for indentation load greater than 5 N. The raw material (without heat treatment) has the VHN and tensile strength of 3413 MPa and 1050.61 MPa respectively and the quenched samples have the VHN and tensile strength of 5407 and 1861 MPa respectively. The Vickers hardness and tensile strength decrease with the increment of tempering temperatures. The higher tempering temperature produces lower hardness and tensile strength. The raw material tensile strength of 1058.8 MPa obtained by tensile test is comparable to its tensile strength of 1050.61 MPa obtained by Vickers indentation. This result indicates that Vickers microindentation is valid to use for evaluating the tensile strength of HQ 705 alloy steel.


2006 ◽  
Vol 05 (02n03) ◽  
pp. 323-329
Author(s):  
YOUNG SOO KANG ◽  
YOUNG HWAN KIM ◽  
YONG JOO KIM

To improve the heat insulating property of EVA (ethylene vinylacetate), monodispersed spherical SiO 2 nanoparticles as inorganic insulating filler were prepared from sodium metasilicate by emulsion method in reverse micelle. In order to make a comparative study about effect of dispersibility on mechanical properties, aggregated microsized- SiO 2 particles were also prepared. Surface modifications of synthesized SiO 2 nanoparticles were accomplished with MPS (mercaptopropyl trimethoxysilane) to maximize homogeneous distribution and compatibility between obtained SiO 2 nanoparticles and EVA. Finally heat insulating nanocomposite film was prepared with MPS coated- SiO 2 nanoparticles at the ratio of 2 wt% and EVA. The insulating capacity was tested by IR spectroscopy and light transmission was observed by UV-vis spectroscopy. The mechanical properties such as tensile strength, elongation, impact strength, tear strength, clarity and haze were also studied.


Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2568
Author(s):  
Chen Nowogrodski ◽  
Ido Simon ◽  
Shlomo Magdassi ◽  
Oded Shoseyov

Second skin is a topically applied, skin-conforming material that mimics human skin properties and bears potential cosmetic and e-skin applications. To successfully integrate with natural skin, characteristics such as color and skin features must be matched. In this work, we prepared bio-based skin-like films from cross-linked keratin/melanin films (KMFs), using a simple fabrication method and non-toxic materials. The films retained their stability in aqueous solutions, showed skin-like mechanical properties, and were homogenous and handleable, with non-granular surfaces and a notable cross-linked structure as determined by attenuated total reflection (ATR). In addition, the combination of keratin and melanin allowed for adjustable tones similar to those of natural human skin. Furthermore, KMFs showed light transmittance and UV-blocking (up to 99%) as a function of melanin content. Finally, keratin/melanin ink (KMI) was used to inkjet-print high-resolution images with natural skin pigmented features. The KMFs and KMI may offer advanced solutions as e-skin or cosmetics platforms.


2020 ◽  
Author(s):  
imane baba ◽  
Mounsif Ibnoussina ◽  
Omar Witam

<p>Over the past few decades, the construction industry has focused on sustainable, environmentally friendly and easily recyclable materials. The objective of this work is to characterize and enhance the thermal conductivity, mechanical strength and setting time of a composite material based on plaster and lime. This material is designed for use in plasters.</p><p>Two types of gypsum are studied, the first one belongs to the Safi basin, the second one characterizes the High Atlas of Marrakech and precisely Douar Tafza. Geologically speaking, the two sites have many similarities. They are characterized by a Meso-Cenozoic age coverage covering a deformed Paleozoic age basement.</p><p>The characterization of the plaster's raw material, gypsum, was necessary to determine its physical and geotechnical properties, mineralogy, thermal behaviour and microscopic structure. Several analyses have been developed such as: pycnometer density measurement, X-ray diffraction, infrared spectroscopy and scanning electron microscopy.</p><p>We made samples, of standardized dimensions, of two mixtures based on the two types of plaster reinforced by the addition of two types of lime from different localities. The latter are from Marrakech and the Agadir region. The water/plaster mass ratio was set at 0.75 and the addition of lime was achieved by increasing its percentage in slices by 12.5% and up to 50%.</p><p>The reinforcement of plaster with lime has enhanced its thermal and mechanical properties and setting time. The measurements show that the addition of lime has reduced the thermal conductivity and increased the mechanical strength of both types of plaster. In addition, following the addition of lime, the setting time has decreased and the basicity of the material has increased. Noting that the intrinsic properties of the raw material influence the mechanical and thermal properties of the material.</p><p><strong>Keywords:</strong>   plaster, enhancement, properties, mechanical, thermal, Morocco</p>


2021 ◽  
Vol 10 (1) ◽  
pp. 1-7
Author(s):  
Rohit Kumar ◽  
Ramratan . ◽  
Anupam Kumar ◽  
Rajinder Singh Smagh

Elephant dung is an excellent source of cellulosic fiber that is a basic requirement for paper making. But they contributed to very small percentage production of elephant dung. So, researchers are trying to find a new area of utilization of elephant dung fiber pulp as in reinforcement’s polymer composite. In this experiment element dung fiber pulp in the natural fiber component chemically treated with alkaline and soda AQ solution in this study, it has been aimed to use elephant dung fiber pulp in composite material and to study mechanical properties of the produced material. The produced composite samples were then characterized using tensile test, Izod impact test, thickness test. The fracture surface of the polymer composite sample was also inspected with the help of SEM. The content of elephant dung fiber pulp is varied (35%, 45%, 55%) weight percentage whereas the epoxy resin is varied (50%, 40%, 30%) percentage is kept constant 15% in hardener. The entire sample has been tested in a universal testing machine as per ASTM standard for tensile strength and impact strength. It is observed that composite with 35% fiber pulp is having the highest tensile strength of 4mm 6.445 Mpa and 8mm 11.80 Mpa. The impact strength of composite with 35% fiber pulp washes highest than 45% to 55% dung fiber pulp. This produces composite sheet will be used for the surfboards, sporting goods, building panel this not only reduces the cost but also save from environmental pollution.


BioResources ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 4171-4199
Author(s):  
Eva Oktoberyani Christy ◽  
Soemarno ◽  
Sumardi Hadi Sumarlan ◽  
Agoes Soehardjono

This study investigated the effects of the pressing temperature on the mechanical and physical properties of binderless bark particleboard made from Gelam bark waste and the improvement of those properties. In addition, the thermal insulation properties of the particleboard were determined. Four different temperatures (140 °C, 160 °C, 180 °C, and 200 °C) were used to make single-layer binderless bark particleboard with a target density of less than or equal to 0.59 g/cm3. Results revealed that the pressing temperature affected the mechanical properties (modulus of rupture, modulus of elasticity, and tensile strength perpendicular to panel surface), which increased as the temperature increased, and the physical properties (thickness swelling and water absorption), which decreased as the temperature increased. Based on the Tukey test, increasing the temperature from 180 to 200 °C did not significantly affect the mechanical or physical properties, except for the tensile strength perpendicular to panel surface. None of the mechanical properties met SNI standard 03-2105-2006 (2006); however, the 12% maximum thickness swelling requirement was met for binderless bark particleboard hot-pressed at 200 °C. Binderless bark particleboard hot-pressed at 200 °C had high water resistance, regardless of its low strength, and a thermal conductivity value of 0.14 W/m∙K.


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