scholarly journals A Nanocellulose Polypyrrole Composite Based on Tunicate Cellulose

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Dawei Zhang ◽  
Qing Zhang ◽  
Xin Gao ◽  
Guangzhe Piao
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Ammonium Persulfate ◽  
High Electrical Conductivity ◽  
Chemical Polymerization ◽  
Transmission Electron ◽  
Mean Size ◽  
Polypyrrole Composite ◽  
Scanning Electron

The water-dispersed conductive polypyrrole (PPy) was prepared via thein situoxidative chemical polymerization by using ammonium persulfate (APS) as oxidant and tunicate cellulose nanocrystals (T-CNs) as a dopant and template for tuning the morphologies of PPy nanoparticles. Highly flexible paper-like materials of PPy/T-CNs nanocomposites with high electrical conductivity values and good mechanical properties were prepared. The structure of nanocomposites of PPy/T-CNs was investigated by using Fourier transform infrared spectroscopy. Scanning electron microscopy and transmission electron microscopy analyses of the composites revealed that PPy consisted of nanoparticles about 2.5 nm in mean size to form a continuous coating covered on the T-CNs. The diameters of the PPy nanoparticles increased from 10 to 100 nm with the increasing pyrrole amount. Moreover, electrical properties of the obtained PPy/T-CNs films were studied using standard four-probe technique and the electrical conductivity could be as high as 10−3 S/cm.

Morphology of Polyethylene/Montmorillonite Nanocomposites Prepared by In Situ Polymerization

2013 ◽  
Vol 457-458 ◽  
pp. 244-247
Author(s):  
Min Li ◽  
Li Guang Xiao ◽  
Hong Kai Zhao
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
In Situ Polymerization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Reflection Peak ◽  
Basal Reflection ◽  
Scanning Electron

Polyethylene/montmorillonite (PE/MMT) nanocomposites were prepared by in situ polymerization. The morphology of MMT/MgCl2/TiCl4 catalyst and PE/MMT nanocomposites was investigated by scanning electron microscopy (SEM). It can be seen that MMT/MgCl2/TiCl4 catalyst remained the original MMT sheet structures and many holes were found in MMT and the morphology of PE/MMT nanocomposites is part of the sheet in the form of existence, as most of the petal structure. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were carried out to characterize all the samples. XRD results reveal that the original basal reflection peak of PEI1 and PEI2 disappears completely and that of PEI3 become very weak. MMT/MgCl2/TiCl4 catalyst was finely dispersed in the PE matrix. Instead of being individually dispersed, most layers were found in thin stacks comprising several swollen layers.

In Situ Fabrication of Nanoscale Graphene Oxide/Polyaniline Composite and its Electrochemical Properties

2010 ◽  
Vol 148-149 ◽  
pp. 1547-1550 ◽  
Author(s):  
Hua Lan Wang ◽  
Qing Li Hao ◽  
Xi Feng Xia ◽  
Zhi Jia Wang ◽  
Jiao Tian ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Graphene Oxide ◽  
Photoelectron Spectroscopy ◽  
In Situ Polymerization ◽  
Ammonium Persulfate ◽  
Polymerization Process ◽  
Electrochemical Test ◽  
X Ray ◽  
Transmission Electron

A graphene oxide/polyaniline composite was synthesized by an in situ polymerization process. This product was simply prepared in an ethylene glycol medium, using ammonium persulfate as oxidant in ice bath. The composite was characterized by field emission scanning electron microscopy, transmission electron microscopy, X-Ray photoelectron spectroscopy, Raman spectroscopy and electrochemical test. The composite material showed a good electrochemical performance.

Preparation of Polyaniline @ Polypyrrole Conductive Composite via In Situ Polymerization

2013 ◽  
Vol 562-565 ◽  
pp. 1137-1142
Author(s):  
Hui Xia Feng ◽  
Bing Wang ◽  
Lin Tan ◽  
Na Li Chen
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
In Situ Polymerization ◽  
Conductive Composite ◽  
The Core ◽  
Novel Method ◽  
Scanning Electron

We prepared the polyaniline@polypyrrole (PAn@PPy) conductive composite by a novel method. The struction like Pre-prepared PAn as the core and PPy as the shell for the composite has been prepared by in-situ polymerization. The PAn@PPy conductive composite presents an electrical conductivity of 12.5 S/cm, which is much higher than pure PAn. The synthesized polymer composites are characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Thermogravimetric analysis (TG). The results indicated that PPy successfully grafted on PAn and the heat resistance of nanocomposite is remarkably increased.

Synthesis of Polyaniline Nanofibrous Networks with the Aid of an Amphiphilic Ionic Liquid

2006 ◽  
Vol 6 (1) ◽  
pp. 227-230 ◽  
Author(s):  
Zhenjiang Miao ◽  
Yong Wang ◽  
Zhimin Liu ◽  
Jun Huang ◽  
Buxing Han ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ionic Liquid ◽  
Oxidative Polymerization ◽  
Ammonium Persulfate ◽  
Molar Ratio ◽  
Transmission Electron ◽  
Scanning Electron

In this work, polyaniline (PANI) nanofibrous networks were prepared using ionic liquid (IL), 1-hexadecyl-3-methylimidazolium chloride (C16MIMCl), as a template through oxidative polymerization of aniline with ammonium persulfate. The resulting PANI was characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis, and FTIR. It was indicated that the as-prepared PANI was in the emeraldine form and its morphology strongly depended on the molar ratio of aniline/C16MIMCl. A possible mechanism for the formation of PANI nanofibrous networks was that the ordered micro-domains of the IL acted as template to direct the growth of the nanostructures.

Microsture and Properties of a Cu-Cr-Zr-Fe-Ti Alloy

2015 ◽  
Vol 723 ◽  
pp. 556-560
Author(s):  
Fu Xiang Huang
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Transmission Electron Microscopy ◽  
Age Hardening ◽  
Peak Hardness ◽  
Ti Alloy ◽  
Hardening Behavior ◽  
Transmission Electron ◽  
Zn Alloys ◽  
Scanning Electron

The effect of 0.45 wt. % Fe and 0.2 wt. % Ti additions on the age hardening behavior of Cu-Cr-Zr-Zn alloys has been investigated with respect to hardness, electrical conductivity and microstructure. It was showed that the addition of Fe /Ti to Cu-Cr-Zr-Zn alloys enhance strength and hardness, but decrease the electrical conductivity, and increase the aging temperature and time for attaining peak hardness. The scanning electron microscope (SEM) and transmission electron microscopy (TEM) results showed that there are four types of phases in the alloy, Cu-matrix, Cr-rich, (Cu,Zr)-rich and (Fe,Ti)-rich phases.

Length Scale Effect on Deformation and Failure Mechanisms of Ultra-Fine Grained Aluminum

2005 ◽  
Vol 907 ◽  
Author(s):  
Khalid Hattar ◽  
J H Han ◽  
D M Follstaedt ◽  
S J Hearne ◽  
T A Saif ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Shear Failure ◽  
Failure Mechanisms ◽  
Deformation And Failure ◽  
Fine Grained ◽  
Transmission Electron ◽  
Microscopic Deformation ◽  
Different Thickness ◽  
Scanning Electron

AbstractThe deformation and failure processes in ultra-fine and nanograined metals over different length scales have been probed using transmission electron microscopy (TEM) and scanning electron microscopy (SEM) in combination with a micromechanical in situ straining device. This novel straining device affords the opportunity to directly correlate the macroscopic mechanical properties with the microscopic deformation and failure mechanisms. Through use of this device it has been shown that increased film thickness results in a transition between limited plasticity and intergranular fracture to global plasticity and shear failure for deposited aluminum samples of similar grain size but different thickness.

scholarly journals Thermal Conductivity of Cu-Cr-Zr-Ti Alloy in the Temperature Range of 300–873 K

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
S. Chenna Krishna ◽  
N. Supriya ◽  
Abhay K. Jha ◽  
Bhanu Pant ◽  
S. C. Sharma ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Room Temperature ◽  
Ofhc Copper ◽  
Ti Alloy ◽  
Phonon Thermal Conductivity ◽  
Temperature Range ◽  
Transmission Electron

In the present investigation, thermal conductivity of Cu-Cr-Zr-Ti alloy was determined as the product of the specific heat (), thermal diffusivity (), and density () in the temperature range of 300–873 K. The experimental results showed that the thermal conductivity of the alloy increased with increase in temperature up to 873 K and the data was accurately modeled by a linear equation. For comparison, thermal conductivity was also evaluated for OFHC copper in the same temperature range. The results obtained were discussed using electrical conductivity and hardness measurements made at room temperature. Transmission electron microscopy (TEM) was done to understand the microstructural changes occurring in the sample after the test. Wiedemann-Franz-Lorenz law was employed for calculating electronic and phonon thermal conductivity using electrical conductivity. On the basis of studies conducted it was deduced that in situ aging may be one of the reasons for the increase in thermal conductivity with temperature for Cu-Cr-Zr-Ti alloy.

scholarly journals Microstructures of Three In-Situ Reinforcements and the Effect on the Tensile Strengths of an Al-Si-Cu-Mg-Ni Alloy

2018 ◽  
Vol 8 (9) ◽  
pp. 1523 ◽  
Author(s):  
Lusha Tian ◽  
Yongchun Guo ◽  
Jianping Li ◽  
Feng Xia ◽  
Minxian Liang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Simultaneous Formation ◽  
X Ray ◽  
Transmission Electron ◽  
Ni Alloy ◽  
Al3ti Phase ◽  
Scanning Electron

In the present paper, the microstructures of three kinds of in-situ reinforcements Al-Ti-C, Al-Ti-B, and Al-Ti-B-C-Ce were deeply investigated using a combination of scanning electron microscopy, X-ray diffraction spectroscopy, and transmission electron microscopy. The effect of in-situ reinforcements on the room temperature and elevated temperature (350 °C) tensile strengths of Al-13Si-4Cu-1Mg-2Ni alloy were analyzed. It is found that doping with trace amounts of B and Ce, the size of the Al3Ti phase in the in-situ reinforced alloy changed from 80 µm (un-reinforced) to about 10 µm, with the simultaneous formation of the AlTiCe phase. The Al-Ti-B-C-Ce reinforcement which is rapid solidified, was more effective and superior to enhance the tensile strengths of the Al-13Si-4Cu-1Mg-2Ni alloy, both at room and high temperatures than those of addition other reinforcements. The room temperature (RT) strength increased by 19.0%, and the 350 °C-strength increased by 18.4%.

Laser ablation of nanoparticles and nanoparticulate, thick Fe1.92Tb0.3Dy0.7 films

2010 ◽  
Vol 25 (9) ◽  
pp. 1733-1740 ◽  
Author(s):  
J. Ma ◽  
M.F. Becker ◽  
J.W. Keto ◽  
D. Kovar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Laser Ablation ◽  
Processing Parameters ◽  
Processing Conditions ◽  
Transmission Electron ◽  
Resistance To Oxidation ◽  
Mean Size ◽  
Scanning Electron

Two laser processes, flat plate ablation (FPA) and laser ablation of microparticle aerosols (LAMA), capable of producing nanoparticles and nanoparticulate thick films of Terfenol-D (Fe1.92Tb0.3Dy0.7) were investigated. The influence of processing parameters on the sizes, compositions, and morphologies of the nanoparticles produced using these processes were studied by transmission electron microscopy. The nanoparticles were used to deposit nanoparticulate films by supersonic impaction with thicknesses ranging from 4 to 50 μm, depending on processing conditions. The microstructures and properties of the films were studied using scanning electron microscopy and magnetometry. The LAMA process produced nanoparticles with a mean size and standard deviation (SD) of 8 to 10 nm ± 5 nm, depending on the type of gas used during synthesis. In contrast, nanoparticles produced using the FPA process exhibited a much broader size distribution varying from 5 to 150 nm and a much greater variation in compositions compared to the LAMA process. Films produced using LAMA also had lower levels of porosity compared to those produced using FPA as a result of the smaller, more uniform nanoparticles from which they were produced and the resulting higher impaction velocities. Compared to the FPA-produced films, the LAMA-produced films exhibited greater resistance to oxidation, higher magnetizations (13–15 emu/g versus 9–11 emu/g, depending on processing conditions) and lower coercivities (versus 41–59 Oe versus 80–110 Oe).

Manufactured Process of High Strength and High Electrical Conductivity Cu-Cr-Zr-Mg Alloy Bars

2017 ◽  
Vol 898 ◽  
pp. 1215-1219 ◽  
Author(s):  
Chun Lei Gan ◽  
Hui Liu ◽  
Kai Hong Zheng ◽  
Yu Ning Liu ◽  
Hai Yan Wang
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Scanning Electron Microscopy ◽  
Tensile Strength ◽  
Precipitation Hardening ◽  
High Strength ◽  
Mg Alloy ◽  
High Electrical Conductivity ◽  
Scanning Electron ◽  
Typical Process

A typical process was developed to manufacture Cu-Cr-Zr-Mg alloy bars with high strength and high electrical conductivity. The microstructure and properties of the alloys were investigated by observations of optical microscopy and scanning electron microscopy, and measurements of tensile strength and electrical conductivity. The results showed that the process and thermo mechanical treatments were successfully developed to manufacture Cu-Cr-Zr-Mg alloy bars with good combinations of the ultimate tensile strength (602.5 MPa) and conductivity (85.4% IACS). The achievement of high strength and high electrical conductivity in the alloy could be ascribed to the interactions of strain hardening and precipitation hardening.

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