Reaction monitoring of polyaniline film formation on carbon nanotubes with TOF-SIMS

2004 ◽  
Vol 231-232 ◽  
pp. 845-849 ◽  
Author(s):  
Wen-Yin Chen ◽  
Chin-Yuen Chen ◽  
Kuang-Yi Hsu ◽  
Chiung-Chi Wang ◽  
Yong-Chien Ling
2020 ◽  
Vol 10 (6) ◽  
pp. 2091 ◽  
Author(s):  
Zuzana Morávková ◽  
Ivana Šeděnková ◽  
Patrycja Bober

There are several types of aniline oligomers that can be formed in the early stages of aniline oxidation: linear oligomers with repeating units joined in para positions, and various branched and polycyclic oligomers, being the two most important groups. The fraction of these different oligomeric groups depends upon the reaction conditions of aniline oxidation. The aim of this study was to analyze the first products of the chemical and electrochemical oxidation of aniline at the (starting) pH 1 and 7, in order to specify the conditions of the formation of phenazine-like oligomers, and to test the theory that they have an important role in polyaniline film formation. We have confirmed that phenazine-like oligomers do not form at pH 1, neither in the chemical nor the electrochemical oxidation of aniline; however, they form in both chemical and electrochemical oxidation of aniline at pH 7. Phenazine-like oligomers are thus definitely not necessary intermediates for PANI film formation, not even in the chemical polymerization of aniline. Finally, the redox behavior of phenazine-like oligomers was demonstrated in a medium at pH 1.


2010 ◽  
Vol 88 (3) ◽  
pp. 267-276 ◽  
Author(s):  
Ş. Uğur ◽  
Ö. Yargi ◽  
Ö. Pekcan

In this study, the effect of multiwalled carbon nanotubes (MWNT) on film formation behaviour and electrical conductivity properties of polystrene (PS) latex film was investigated by using the photon transmission technique and electrical conductivity measurements. Films were prepared by mixing PS latex with different amounts of MWNTs, varying in the range between 0 and 20 wt%. After drying, MWNT content films were separately annealed above the glass transition temperature (Tg) of PS, ranging from 100 to 270 °C, for 10 min. To monitor film formation behavior of PS–MWNT composites, transmitted light intensity, Itr, was measured after each annealing step. The surface conductivity of annealed films at 170 °C was measured and found to increase dramatically above a certain fraction of MWNT (4 wt%) following the percolation theory. This fraction was defined as the percolation threshold of conductivity, Rc. The conductivity scales with the mass fraction of MWNT as a power law with exponent 2.27, which is extremely close to the value of 2.0 predicted by percolation theory. In addition, the increase in Itr during annealing was explained by void closure and interdiffusion processes. Film formation stages were modeled and the corresponding activation energies were measured.


2008 ◽  
Vol 27 (6) ◽  
pp. 683-687 ◽  
Author(s):  
Li Ma ◽  
Jun Yan ◽  
Mengyu Gan ◽  
Wei Qiu ◽  
Ling He ◽  
...  

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Qun Ma ◽  
Ping Wang ◽  
Xiaomin Chen ◽  
Chunqing Zhang

Abstract Plasma electrolytic oxidation (PEO) ceramic coating modified by carbon nanotubes (CNTs) was prepared on Mg–Gd–Y alloy. The microstructure, hydrophobicity and corrosion resistance of the coating were investigated by SEM, contact angle meter and electrochemical test system. Carbon nanotubes (CNTs) are staggered in the ceramic coating and partially filled with plasma discharge micropores. To some extent, CNTs can promote the plasma discharge and improve the film formation rate. With the increase of the content of CNTs, the content of carbon nanotubes in the ceramic coating increases. CNTs can effectively improve the hydrophobicity of ceramic coating. With the increase of the content of CNTs, the corrosion potential E coor and polarization resistance R p increase, the corrosion current i coor decreases and the AC impedance |Z| increases, which leads to the decrease of corrosion rate.


e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Sergio Bocchini ◽  
Emanuela Annibale ◽  
Alberto Frache ◽  
Giovanni Camino

AbstractMultiwall carbon nanotubes (MWNT) were melt blended at different concentration with linear low density polyethylene (LLDPE). The nanotubes impart the fire-retardant characteristics to the polymer by formation of a thin protective film of MWNT/carbon char generated on the surface of the nanocomposites. The film formation mechanism is discussed


2004 ◽  
Vol 53 (8) ◽  
pp. 1180-1184 ◽  
Author(s):  
MM Ayad ◽  
MA Sheneshin

2004 ◽  
Vol 142 (1-3) ◽  
pp. 101-106 ◽  
Author(s):  
M.M Ayad ◽  
N Salahuddin ◽  
M.A Shenashin

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