Mechanical and Barrier Properties of Polyvinyl Alcohol Films Modified with Carbon Nanotubes and Zinc Oxide

2021 ◽  
Vol 877 ◽  
pp. 27-33
Author(s):  
Ya Li Sun ◽  
Yi Hua Wen ◽  
Qing Cai Liu ◽  
Jui Chin Chen ◽  
Manual Reyes de Guzman ◽  
...  

A solution blending technique was employed to form a nanocomposite film of polyvinyl alcohol modified with carbon nanotube and zinc oxide (CNT/ZnO). The film was characterized using a tensile testing machine, X-ray diffraction, scanning electron microscopy, a contact angle device, and barrier property measurement. When the CNT/ZnO content was 1.2 phr, the results from mechanical property and water vapor permeation tests showed that the nanocomposite film had good tensile strength and water resistance. Moreover, CNT/ZnO improved the hydrophobicity of the film. CNT/ZnO/can improve the performance of PVA and is a good nanofiller of PVA. The results of this research might have the opportunity to be used as packaging film materials in the future.

2014 ◽  
Vol 591 ◽  
pp. 43-46
Author(s):  
M. Selvakumar ◽  
G.P. Rajamani ◽  
K. Kalaiselvan

The present work focuses on the fabrication of aluminum (6061-T6) matrix composites (AMCs) reinforced with various weight percentages of SiC particulates using sand casting method. The addition of Mg in the melt during the process has improved the wettability between Al and SiC there by reduced the formation of SiO2 layer on the surface. The fabricated AMCs were characterized using optical microscopy (OM), scanning electron microscopy (SEM), hardness tester and universal tensile testing machine. The OM and SEM images revealed the presence of homogeneous dispersion of SiC particle in the matrix. Using X-ray diffraction (XRD) test, the dispersion of reinforcement has been identified. With the increases in weight percentage of SiC particles in the aluminum matrix improved the mechanical properties of composites.


2013 ◽  
Vol 423-426 ◽  
pp. 771-774
Author(s):  
Ning Ma ◽  
Huan Tao Wu ◽  
Fu Xing Ye ◽  
Guo Sheng Zhang

In this work, a scrapped cross shaft which was assembled at the differential of ZL50C loader was analyzed by scanning electron microscopy (SEM) to examine the failure mechanism and was remanufactured by HVOF with ~500μm thickness WC-12Co coatings on it. The microstructure, phase compositions and properties of deposited WC-12Co coatings were investigated through optical microscope (OM), SEM, X-ray diffraction (XRD), microhardness tester and tensile testing machine. The results show that the coatings were very dense, and their porosities were lower than 1%. According to the X-ray Diffraction (XRD) analysis, the phase compositions of the sprayed coatings consisted of WC, Co and W2C. The microhardness of the coating was approximated to 1100 HV0.1and the bonding strength was higher than 63.7 MPa. It can be concluded that WC-12Co coating sprayed by HVOF was suitable for the remanufacturing of shaft parts.


2020 ◽  
Vol 988 ◽  
pp. 65-72
Author(s):  
Ferriawan Yudhanto ◽  
Jamasri ◽  
Heru Santoso Budi Rochardjo

A method using a combination of acid hydrolysis and ultrasonic homogenize were developed to obtain the CNF (cellulose nanofibers) from agave cantala fibers. Acid hydrolysis method able to produce the CNF with a diameter around of 45-50 nm, which can investigated by transmission electron microscopy (TEM). The homogenize mixing method between CNF 5 wt% colloidal and 3 wt% PVA (polyvinyl alcohol) with magnetic stirrer 350 RPM, at temperature of 50 °C, for 30 minutes followed by ultrasonic homogenizer has been causing CNF well distributed in the PVA matrix. PVA/CNF nanocomposites film was prepared by solution casting technique. Physical properties test by x-ray diffraction (XRD) and fourier transform infrared (FTIR) shows highly crystalline of CNF which indicates improvements the mechanical properties of PVA/CNF nanocomposite film. The tensile stress and elongation at break of PVA/CNF nanocomposite film were increased by 55 % and 137 %.


2011 ◽  
Vol 322 ◽  
pp. 139-143
Author(s):  
Jin Zhu Zhang ◽  
Jun Huang

The microstructure and compressive strength were investigated by means of optical microscopy, X-ray diffraction, and tensile testing machine. The influence of basicity, SiO2 and Al2O3 content on sintering property of hematite ore was studied. The results show that when the silica content was either 5.3% or 5.6%, the best result of the compressive strength of samples obtained at middle basicity. While the silica content was up to 5.9%, the greatest value of the compressive strength of samples attained at lower basicity.


Author(s):  
T. A. Emma ◽  
M. P. Singh

Optical quality zinc oxide films have been characterized using reflection electron diffraction (RED), replication electron microscopy (REM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Significant microstructural differences were observed between rf sputtered films and planar magnetron rf sputtered films. Piezoelectric materials have been attractive for applications to integrated optics since they provide an active medium for signal processing. Among the desirable physical characteristics of sputtered ZnO films used for this and related applications are a highly preferred crystallographic texture and relatively smooth surfaces. It has been found that these characteristics are very sensitive to the type and condition of the substrate and to the several sputtering parameters: target, rf power, gas composition and substrate temperature.


2011 ◽  
Vol 3 (8) ◽  
pp. 91-93 ◽  
Author(s):  
Sindhu Honmute ◽  
◽  
Arunkumar Lagashetty ◽  
A. Venkataraman A. Venkataraman

e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 433-442
Author(s):  
Hua He ◽  
Rui-jing Jia ◽  
Kai-qiang Dong ◽  
Jia-wen Huang ◽  
Zhi-yong Qin

Abstract A novel biodegradable protein-based material (UMSPIE) that consists of natural polymer soy protein isolate (SPI), ultrasonic-modified montmorillonite (UMMT), and ethylene glycol diglycidyl ether (EGDE) was produced by solution casting. Fourier infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TG), and scanning electron microscopy (SEM) were used to characterize the chemical structure and micro-morphologies of as-synthesized protein-based composite films. The results showed that the interlayer structure of MMT was destroyed by ultrasonic treatment, and the hydrogen bonding between SPI chains and the ultrasound-treated MMT plates was enhanced. The synergistic effect of UMMT and EGDE on SPI molecules made the network structure of the UMSPIE film denser. In addition, the mechanical and barrier properties of the as-synthesized films were explored. Compared with pure soy protein film, the tensile strength of the UMSPIE film has an increase of 266.82% (increasing from 4.4 to 16.14 MPa). From the above, the modified strategy of layered silicates filling combining crosslinking agents is considered as an effective method to improve the functional properties of bio-based polymer composites.


Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2062
Author(s):  
Yu-Hsun Nien ◽  
Zhi-Xuan Kang ◽  
Tzu-Yu Su ◽  
Chih-Sung Ho ◽  
Jung-Chuan Chou ◽  
...  

Potentiometric biosensors based on flexible arrayed silver paste electrode and copper-doped zinc oxide sensing film modified by iron-platinum nanoparticles (FePt NPs) are designed and manufactured to detect lactate in human. The sensing film is made of copper-doped zinc oxide (CZO) by a radio frequency (RF) sputtering system, and then modified by iron-platinum nanoparticles (FePt NPs). The surface morphology of copper-doped zinc oxide (CZO) is analyzed by scanning electron microscope (SEM). FePt NPs are analyzed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The average sensitivity, response time, and interference effect of the lactate biosensors are analyzed by voltage-time (V-T) measurement system. The electrochemical impedance is analyzed by electrochemical impedance spectroscopy (EIS). The average sensitivity and linearity over the concentration range 0.2 mM–5 mM are 25.32 mV/mM and 0.977 mV/mM, respectively. The response time of the lactate biosensor is 16 s, with excellent selectivity.


Author(s):  
A. Olivier ◽  
J. Wannenburg ◽  
R.D. Gottschalk ◽  
M.J. Van der Linde ◽  
H.T. Groeneveld

A shoe was designed to combine the advantages of a reverse shoe and an adjustable heart bar shoe in the treatment of chronic laminitis. This reverse even frog pressure (REFP) shoe applies pressure uniformly over a large area of the frog solar surface. Pressure is applied vertically upward parallel to the solar surface of the frog and can be increased or decreased as required. Five clinically healthy horses were humanely euthanased and their dismem-bered forelimbs used in an in vitro study. Frog pressure was measured by strain gauges applied to the ground surface of the carrying tab portion of the shoe. A linear variable distance transducer (LVDT) was inserted into a hole drilled in the dorsal hoof wall. The LVDT measured movement of the third phalanx (P3) in a dorsopalmar plane relative to the dorsal hoof wall. The vertical component of hoof wall compression was measured by means of unidirectional strain gauges attached to the toe, quarter and heel of the medial hoof wall of each specimen. The entire limb was mounted vertically in a tensile testing machine and submitted to vertical downward compressive forces of 0 to 2500 Nat a rate of 5 cm/minute. The effects of increasing frog pressure on hoof wall weight-bearing and third phalanx movement within the hoof were determined. Each specimen was tested with the shoe under the following conditions: zero frog pressure; frog pressure used to treat clinical cases of chronic laminitis (7 N-cm); frog pressure clinically painful to the horse as determined prior to euthanasia; frog pressure just alleviating this pain. The specimens were also tested after shoe removal. Total weight-bearing on the hoof wall at zero frog pressure was used as the basis for comparison. Pain-causing and pain-alleviating frog pressures decreased total weight-bearing on the hoof wall (P < 0.05). Frog pressure of 7 N-cm had no statistically significant effect on hoof wall weight-bearing although there was a trend for it to decrease as load increased. Before loading, the pain-causing and pain-alleviating frog pressures resulted in a palmar movement of P3 relative to the dorsal hoof wall compared to the position of P3 at zero frog pressure (P < 0.05). This difference remained statistically significant up to 1300 Nload. At higher loads, the position of P3 did not differ significantly for the different frog pressures applied. It is concluded that increased frog pressure using the REFP shoe decreases total hoof wall weight-bearing and causes palmar movement of P3 at low weight-bearing loads. Without a shoe the toe and quarter hoof wall compression remained more constant and less in magnitude, than with a shoe.


Proceedings ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. 39
Author(s):  
Zahira. El khalidi ◽  
Maryam Siadat ◽  
Elisabetta. Comini ◽  
Salah. Fadili ◽  
Philippe. Thevenin

Chemical gas sensors were studied long ago and nowadays, for the advantageous role they provide to the environment, health condition monitoring and protection. The recent studies focus on the semiconductors sensing abilities, especially of non toxic and low cost compounds. The present work describes the steps to elaborate and perform a chemical sensor using intrinsic and doped semiconductor zinc oxide. First, we synthesized pure oxide using zinc powder, then, two other samples were established where we introduced the same doping percentage of Al and Sn respectively. Using low cost spray pyrolysis, and respecting the same conditions of preparation. The obtained samples were then characterized by X Ray Diffraction (XRD) that revealed the hexagonal wurzite structure and higher crystallite density towards the direction (002), besides the appearance of the vibration modes related to zinc oxide, confirmed by Raman spectroscopy. SEM spectroscopy showed that the surface morphology is ideal for oxidizing/reduction reactions, due to the porous structure and the low grain sizes, especially observed for the sample Sn doped ZnO. The gas testing confirms these predictions showing that the highest response is related to Sn doped ZnO compared to ZnO and followed by Al doped ZnO. The films exhibited responses towards: CO, acetone, methanol, H2, ammonia and NO2. The concentrations were varied from 10 to 500 ppm and the working temperatures from 250 to 500°C, the optimal working temperatures were 350 and 400 °C. Sn doped ZnO showed a high response towards H2 gas target, with a sensitivity reaching 200 at 500 ppm, for 400 °C.


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