Conductivity and Thermal-Stability of 5-Sulfosalicylic Acid Sodium Doped Polypyrrole

2010 ◽  
Vol 428-429 ◽  
pp. 579-582 ◽  
Author(s):  
Fu Fang Zhou ◽  
Bao Gai Zhai ◽  
Chun Xu Pan ◽  
Yuan Ming Huang

By varying the dopant-to-pyrrole ratio in a wide range from 0 to 60% a series of 5-sulfosalicylic acid sodium doped polypyrrole was synthesized in situ in aqueous solution with ferric chloride as the oxidant. The resulting polypyrroles were characterized with the four-probe, laser light scattering and thermo-gravimetry analysis, differential thermal analysis, respectively. Our results indicate that the particle size plays a determinative role to tune the conductivity in the studied range of dopant concentration; and this series of polypyrrole with size-tuned-conductivity exhibits little less thermal-stability although its size and conductivity changes simultaneously and acutely with the dopant concentration. The association of the conductivity with particle size was interpreted in terms of a theoretical model proposed by Baughman and Shacklelette.

2010 ◽  
Vol 428-429 ◽  
pp. 548-551 ◽  
Author(s):  
Fu Fang Zhou ◽  
Bao Gai Zhai ◽  
Chun Xu Pan ◽  
Yuan Ming Huang

By varying the dopant-to-monomer ratio in a wide range of 0―110%, a series of polypyrroles doped with 9,10-anthraquinone-2-sulfonic acid sodium were synthesized by polymerizing the monomer pyrrole in aqueous solution of ferric chloride. The resulted polypyrroles were characterized with the four-probe, laser light scattering and differential thermal analysis, respectively. Our results indicated that the average particle size dominates the change in conductivity and thermal stability for the resulted polypyrrole at different dopant concentration.


2014 ◽  
Vol 6 (2) ◽  
pp. 1122-1134 ◽  
Author(s):  
Mokhtar Hemdan Abd El-Salam

Due to the light weight, high specific strength and non hazardous nature of bamboo fiber, it is preferred over synthetic fibers in composite materials for a wide range of applications such as automotive industry and including household sectors. As was noticed, little attention has been given to the effect of bamboo powder on the mechanical properties of rubber composites. Hence, an attempt has been made in this paper to the study the effect of loading and particle size of bamboo powder on the mechanical properties of EPDM composites. Thermo-gravimetric analysis (TGA) was carried out to study the thermal stability of composites. Results indicated that the thermal stability of EPDM was further improved with increasing in bamboo loading and decreasing in particle size. The stress- strain curves of the composites were studied and fitted according toOgden’s model. Mechanical parameters for the studied composites were improved with increasing bamboo loading. Besides, properties such as rupture stress, and internal friction were found to be maximum for composites containing certain content of bamboo powder, depending upon its particle size. Moreover, composites containing the smallest particle size of powder, at all levels of bamboo loading, showed mechanical properties superior to all other composites. From the dynamic mechanical measurements, the dynamic modulus, internal friction, and thermal diffusivity were calculated. The observed variations were explained in view of the role played by both the loading level and the particle size of bamboo powder. These findings were supported by scanning electron microscopy (SEM) micrographs.


1993 ◽  
Vol 324 ◽  
Author(s):  
C. Pickering ◽  
D.A.O. Hope ◽  
W.Y. Leong ◽  
D.J. Robbins ◽  
R. Greef

AbstractIn-situ dual-wavelength ellipsometry and laser light scattering have been used to monitor growth of Si/Si1−x,Gex heterojunction bipolar transistor and multi-quantum well (MQW) structures. The growth rate of B-doped Si0 8Ge0.2 has been shown to be linear, but that of As-doped Si is non-linear, decreasing with time. Refractive index data have been obtained at the growth temperature for x = 0.15, 0.20, 0.25. Interface regions ∼ 6-20Å thickness have been detected at hetero-interfaces and during interrupted alloy growth. Period-to-period repeatability of MQW structures has been shown to be ±lML.


1993 ◽  
Vol 16 (5) ◽  
pp. 260-264 ◽  
Author(s):  
H.Y. Tong ◽  
B.Z. Ding ◽  
H.G. Jiang ◽  
Z.Q. Hu ◽  
L. Dong ◽  
...  

2007 ◽  
Vol 50 (3) ◽  
pp. 677 ◽  
Author(s):  
Jae-Wook Jae-Wook ◽  
Kyung-Hwan Kyung-Hwan ◽  
Hyoungsub Hyoungsub ◽  
Cheol-Woong Cheol-Woong ◽  
Dongwon Dongwon ◽  
...  

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 210
Author(s):  
Xiangdong Yang ◽  
Haitao Wang ◽  
Peng Wang ◽  
Xuxin Yang ◽  
Hongying Mao

Using in situ ultraviolet photoelectron spectroscopy (UPS) and X-ray photoelectron spectroscopy (XPS) measurements, the thermal behavior of octadecyltrichlorosilane (OTS) and 1H, 1H, 2H, and 2H-perfluorooctyltriethoxysilane (PTES) monolayers on SiO2 substrates has been investigated. OTS is thermally stable up to 573 K with vacuum annealing, whereas PTES starts decomposing at a moderate temperature between 373 K and 423 K. Vacuum annealing results in the decomposition of CF3 and CF2 species rather than desorption of the entire PTES molecule. In addition, our UPS results reveal that the work function (WF)of OTS remains the same after annealing; however WF of PTES decreases from ~5.62 eV to ~5.16 eV after annealing at 573 K.


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