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1

Polimeryzacja aniliny w środowisku stałego pola magnetycznego

Miękoś Ewa, Samujło Bronisław, Zieliński Marek, Sroczyński Dariusz

Polimery

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2021

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T. 66, nr 7-8

383--388

PL

Badano wpływ stałego pola magnetycznego (SPM) na proces polimeryzacji polianiliny. Proces prowadzono na platynowych elektrodach płytkowych, nieizolowanych i izolowanych jednostronnie (z dwóch różnych stron teflonem), o powierzchniach skierowanych równolegle do linii sił SPM. Stwierdzono, że właściwości magnetyczne cząstek biorących udział w procesie polimeryzacji elektrochemicznej oraz ich ładunek (+/–) mają istotny wpływ na oddziaływanie SPM na przebieg procesu. Zaproponowano mechanizm wpływu SPM na zachodzące reakcje elektrochemiczne, oparty na powstawaniu efektu magnetohydrodynamicznego (MHD), powodującego zmianę szybkości transportu reagujących substancji w kierunku elektrody.

EN

The influence of the constant magnetic field (CMF) on the polymerization of polyaniline was investigated. The process was carried out on platinum plate electrodes, non-insulated and one-sided Teflon insulated (from two different sides), with surfaces directed parallel to the CMF line of force. It was found that the magnetic properties of the particles involved in the electrochemical polymerization process and their charge (+/-) have a significant impact on the influence of the CMF on the course of the process. The mechanism of the influence of CMF on the studied electrochemical reactions was proposed, based on the formation of the magnetohydrodynamic effect (MHD), causing a change in the rate of transport of the reacting substances towards the electrode.

2

Electrical Conductivity and Morphology Study of Polyaniline Powder Synthesised with Various Doping Ions

Golba S., Popczyk M., Miga S., Jurek-Suliga J., Zubko M.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 3

1023--1028

EN

Powdered polyaniline (PANI) was synthesised chemically with different doping anions namely hydrochloric acid, sulphuric acid and para-toluenesulfonic acid (pTSA). Two-step synthetic procedure was utilised at low temperature. The highest reaction efficiency was found for chlorine-doped PANI. Structural characterization with FTIR revealed the vibration bands characteristicto formation of the emeraldine salt. The surface morphology of doped PANIs was studied by SEM images which showed near globular shape and porous structures with different size of the aggregated particles. They were smaller for Cl-- or pTS--doped PANI while for SO4 2- the size was markedly larger. The XRD patterns revealed that there are ordered regions especially for pTS- doped PANI, while the highest conductivity value was recorded for Cl- doped one followed by organic pTS- doped and SO4 2- doped one.

3

Electrical characteristics of PVA-PANI-ZnS nanocomposite film synthesized by gamma irradiation method

Bahrami A., Behzad K., Faraji N., Kharazmi A.

Materials Science Poland

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2018

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Vol. 36, No. 1

102--106

EN

This work presents the synthesis of PANI-PVA-ZnS nanocomposite films by gamma irradiation approach. The samples were irradiated with different doses ranging from 10 kGy to 40 kGy. Subsequently, structural, morphological, optical and electrical characteristics of the samples were investigated. Fourier transform infrared (FT-IR) spectroscopy was employed to study the chemical structure of the samples. Field emission scanning electron microscopy (FE-SEM) was used to investigate the morphology of nanocomposites. The electronic absorption characteristics of the samples were measured by means of UV-Vis spectroscopy. The AC and DC electrical behaviors of the samples were characterized using LCR meter in the frequency range of 20 Hz to 1 MHz. The impedance values of the samples were extracted from Cole-Cole plots and consequently DC conductivity was calculated.

4

PANI/NaTaO3 composite photocatalyst for enhanced hydrogen generation under UV light irradiation

Zielińska B., Schmidt B., Mijowska E., Kaleńczuk R.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 3

115--119

EN

A PANI/NaTaO3 composite was successfully synthesized by an oxidative polymerization of aniline monomer in hydrochloric acid solution containing sodium tantalate. NaTaO3 at a monoclinic structure was produced via hydrothermal method. The photocatalytic activities of the unmodified NaTaO3 and PANI/NaTaO3 were evaluated for hydrogen generation from an aqueous HCOOH solution and under UV light irradiation. The results showed that the evolution rate of H2 increased significantly when NaTaO3 was modified with PANI. The enhancement of the photocatalytic activity of PANI/NaTaO3 composite was ascribed to the effective charge transfer and separation between NaTaO3 and PANI, which reduced their recombination. This indicates that PANI modification of tantalate photocatalysts may open up a new way to prepare highly efficient catalytic materials for H2 generation.

5

Determination of ascorbic acid using differential pulse voltammetry method on aniline-co-para–aminophenol modified electrode

Parsa A., Tajik M.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 2

125--129

EN

The electro-synthesis of poly(aniline-co-para–aminophenol) on graphite electrode was examined using cyclic voltammetry (CV) over the potential window of −0.2 V to 1 V in phosphoric acid medium, which was comprised of potassium chloride and para–Toluene sulfonic acid (pTSA) as electrolyte support. Fourier transform infrared (FTIR) spectroscopy was employed to identify the electro-synthesized copolymer while impedance techniques were used to determine charge transfer resistance (Rct) in modified and unmodified electrodes. After this, the electro-catalytic effect of the modified electrode on ascorbic acid was examined using differential pulse voltammetry (DPV) and a very strong response was observed. A negative shift of about 0.33 V was found in the peak anodic potentials for ascorbic acid. Measurement using DPV indicated a proper response by the electrode to a wide range of ascorbic acid concentrations, from 0.0001 to 0.0004 M. The peak anodic currents for increased concentrations showed a proper linear range.

6

Effect of solvents on structural anisotropy of polyaniline thin films

Śniechowski M., Kozik T., Łużny W.

Polimery

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2017

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T. 62, nr 11-12

855--860

EN

X-ray surface diffraction experiments performed on polyaniline/camphorsulfonic acid (PANI/CSA) thin films reveal high anisotropy of the five main crystalline peaks. This anisotropy is different for samples cast from m-cresol and cast from trifluoroacetic acid (TFA). Taking advantage of a recently published crystalline unit cell model, intensity distribution maps are calculated for these two types of samples. The anisotropy is in agreement with experiment, further validating the PANI/CSA model and showing that solvent molecules are not present in the unit cell.

PL

Cienkowarstwowe, wykazujące silną anizotropię próbki polianilina/kwas kamforosulfonowy (PANI/CSA) zbadano metodą dyfrakcji powierzchniowej promieniowania rentgenowskiego. Wyniki pomiarów w geometriach: transmisyjnej, odbiciowej i pośrednich wykazały różnice między natężeniami pięciu głównych maksimów krystalicznych. Anizotropia próbek była różna w wypadku użycia różnych rozpuszczalników (m-cresol, kwas trifluorooctowy). Niedawno opublikowany model struktury PANI/CSA wykorzystano do obliczenia map natężeń, a następnie do porównań z wynikami pomiarów. Proponowany model poprawnie opisuje uporządkowanie w próbkach folii z PANI/CSA wylanych z różnych rozpuszczalników, bez konieczności uwzględniania w nim cząsteczek rozpuszczalnika. Świadczy to o tym, że cząsteczki rozpuszczalnika nie występują w strukturze PANI/CSA jako składniki komórki elementarnej.

7

Challenge and adventure: twenty years of searching for the model structure of the polyaniline/camphorsulfonic acid conducting polymer system leading to an artificial intelligence approach

Kozik T., Śniechowski M., Łużny W.

Polimery

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2017

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T. 62, nr 11-12

800--805

EN

The search for the model structure of polyaniline/camphorsulfonic acid (PANI/CSA) began approximately twenty years ago and remained an unsolved problem. Recently, a new molecular dynamics based model was published in which the system forms a structure of alternating double layers. Having brought together all available information regarding the system, an artificial intelligence approach was formulated, which resulted in finding a model of the crystalline regions of the polymer system in agreement with various experimental results. The approach is thoroughly described due to its versatility.

PL

Poszukiwania modelu struktury systemu polianilina/kwas kamforosulfonowy (PANI/CSA) rozpoczęły się przed ok. dwudziestu laty, nadal jednak problem pozostaje nierozwiązany. W minionych latach opublikowano nowy model otrzymany w wyniku symulacji metodą dynamiki molekularnej. Zgodnie z jego przewidywaniami w systemie PANI/CSA powstaje struktura naprzemiennych dwuwarstw. Na podstawie dostępnej wiedzy sformułowano wykorzystującą algorytmy sztucznej inteligencji metodę, która doprowadziła do znalezienia modelu wykazującego zgodność z różnego rodzaju doświadczeniami. Ze względu na uniwersalność opracowanej metody, szczegółowo ją opisano.

8

Double-layer microwave absorber based on nanocrystalline CoFe2O4 and CoFe2O4/PANI multi-core/shell composites

Xu Y., Shen G., Wu H., Liu B., Fang X., Zhang D., Zhu J.

Materials Science Poland

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2017

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Vol. 35, No. 1

94--104

EN

Organic-inorganic nano-CoFe2O4/PANI (polyaniline) multi-core/shell composites have been successfully synthesized by chemical oxidative polymerization of aniline. The characterization results showed that the ferrite nanocrystals were efficiently embedded in PANI. The electromagnetic parameters of the composites were measured by a vector network analyser in the frequency range of 2 GHz to 18 GHz. Double-layer absorbers based on the CoFe2O4/PANI composite (matching layer) and calcined CoFe2O4 ferrite (absorbing layer) have been designed. The reflection loss of the microwave absorbers of both single layer and double-layer with a total thickness of 2.0 mm and 2.5 mm was calculated according to transmission-line theory. The results indicated that the minimum reflection loss of the CoFe2O4/PANI composite was −19.0 dB at 16.2 GHz at the thickness of 2.0 mm and −23.6 dB at 13.1 GHz at the thickness of 2.5 mm, respectively. The minimum reflection loss for double-layer absorbers reached −28.8 dB at 16.2 GHz at the total thickness of 2.0 mm, and −31.1 dB at 12.8 GHz at the total thickness of 2.5 mm. The absorption bandwidth under −10 dB was 4.2 GHz (13.8 GHz to 18.0 GHz) and 5.5 GHz (10.3 GHz to 15.8 GHz), respectively. The results show that the reflection loss and absorption bandwidth of the double-layer absorbers are obviously enhanced compared to corresponding single layer absorbers.

9

Synthesis of Conductive Cocoon Silk Composites

Kaitsuka Y., Goto H.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 1 (121)

17--23

EN

Herein we report on the preparation of polyaniline (PANI) composite using a cocoon by in situ chemical oxidative polymerisation. The composites thus prepared were characterised by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), infrared (IR), and electron spin resonance (ESR) spectroscopy. We confirmed the PANI/cocoon composite and subsequent carbonisation allowed the formation of micro-sized wafer-shaped carbon. The polymerisation reaction occurs in a chiral reaction field of the silk surface, which can be referred to as bio-interface polymerisation.

PL

W artykule opisano przygotowanie polianilinowych (PANI) kompozytów przy zastosowaniu kokonów i przeprowadzeniu in situ chemicznej utleniającej polimeryzacji. Wytworzone kompozyty zostały scharakteryzowane za pomocą skaningowego mikroskopu elektronowego (SEM), analizy termograwimetrycznej (TGA), spektrofotometrii w podczerwieni (IR) oraz elektronowego rezonansu spinowego (ESR). Potwierdzono, że otrzymane kompozyty, a następnie ich karbonizacja umożliwiły powstawanie mikroskopijnej wielkości płytek węglowych.

10

Polyaniline doped with acids. Methods of synthesis and modification

Kolasińska E., Mazurek B.

Prace Instytutu Elektrotechniki

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2016

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Z. 274

61--69

PL

Prowadzone badania miały na celu opracowanie składu surowcowego i technologii wytwarzania półprzewodzących materiałów na bazie polianiliny. Takie tworzywa o prostych metodach wytwarzania, dodatkowo lekkie i wytrzymałe termicznie można stosować w elektrotechnice, elektronice, czy przemyśle motoryzacyjnym, jako generatory prądu, elementy chłodzące bądź do odzysku ciepła. Przedstawiono technologię wytwarzania materiałów półprzewodzących na bazie polianiliny modyfikowanej pojedynczym kwasem solnym lub kamforosulfonowym oraz układem dwóch kwasów organicznych. Określono wpływ rodzaju zastosowanego kwasu na przewodność elektryczną polimeru. Wykonano analizę termiczną dla otrzymanych materiałów.

EN

The research was aimed at the development of the composition and technology of semiconducting materials based on polyaniline. Such materials, which have simple methods of production, are lightweight and have high thermal resistance, may be used in electrotechnical, electronic, and automotive devices, such as power generators and cooling or heat recovery elements. The technology for the production of semiconductive materials based on polyaniline-modified hydrochloric or camphorsulfonic acid is presented. The influence of the acid type on the electrical conductivity of the polymer was determined. Thermal analysis was performed for the obtained materials.

11

Synthesis of polyaniline nanotubes through UV light catalytic method

Sun C., Wang Y.

Materials Science Poland

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2015

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Vol. 33, No. 1

193--197

EN

In this study, nitrocellulose (NC) fiber blanket prepared by electrostatic spinning method has been used as a template, and copper nitrate (Cu(NO3)2)) as an oxidant to synthesise polyaniline nanotubes doped with heteropolyacid (H4)SiW12)O40), SiW12) using UV light catalytic method. Infrared spectroscopy (IR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) technologies were applied to characterize the prepared samples of polyaniline nanotubes. The results show that the external diameter of the tube is about 200 nm, and the internal diameter about 170 nm. We also give a reasonable speculation and explanation about the formation mechanism of the nanotubes.

12

Modeling of the crystalline structure of the complex system containing doped polyaniline by use of genetic algorithms

Kozik T., Luzny W.

Journal of Education and Technical Sciences

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2015

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Vol. 2, nr 1

9--14

EN

The structure of polyaniline (PANI) protonated with camphorsulphonic acid (CSA) has been subject to research for a long time. Despite several, various models being proposed throughout the years, there is still no model widely accepted as the only correct and final one of its crystalline phase. In this paper a computer program named MoleculeEditor is described. Created basing on the concepts of an existing but significantly different program named CrystalFinder, it is a software dedicated to finding a model of the crystalline regions of the PANI/CSA system based on an input X-ray diffraction pattern. In its search it takes advantage of the genetic algorithm technique for optimizing the model parameters to fit the computed diffraction pattern to the one loaded as input. A successful example of it being employed to find the parameters of a prepared beforehand, fictional structure of the system, is presented. Conclusions drawn from this application of the prepared software cannot be ignored in the further search for the actual model of this complex system using this program. Obtaining results from MoleculeEditor for actual, experimental data is however still in progress.

13

Cultivation of paramecium caudatum in the presence of physiologically active substances, and a redox active polymer

Goto H., Nakajima K.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 46

26--29

EN

Cultivation of paramecium in the presence of physiologically active substances was carried out. We have monitored paramecium for 23 days in the solutions in the presence of physiologically active substances, and polyaniline as a redox active polymer.

14

Chemical Polymerisation of Aniline in the Presence of Sericin

Kaitsuka Y., Goto H.

International Letters of Chemistry, Physics and Astronomy

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2015

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Vol. 46

48--53

EN

A series of polyaniline/sericin composites were prepared by oxidative polymerisation of aniline in the presence of sericin. The preparation of polyaniline composites containing sericin were confirmed by Fourier-transform infrared spectroscopy. From the result of electron spin resonance spectroscopy, the electron spin concentration of the composites decreases with sericin/aniline ratio in the polymerisation. Circular dichroism absorption spectroscopy measurements revealed that sericin influences aggregation state of polyaniline. Scanning electron microscopy suggested that the polyaniline composites show granular morphology. The composites display macroporous structure after carbonization.

15

Polyaniline/CaTi0.8Fe0.2O3 composites for humidity sensors

Łańcucki Ł., Pasierb P.

Composites Theory and Practice

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2015

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R. 15, nr 4

233-242

EN

Polyaniline (PANI) is a conductive polymer material with a huge potential for constructing different electrochemical devices. Different strategies can be used to modify and optimize polymer properties from the point of certain applications, e.g. for the construction of gas sensors. Among those strategies, the formation of composite materials comprising PANI as the base material and ceramic powder material as a modifier is a promising approach. In this work the results concerning the influence of CaTi0.8Fe0.2O3 (CTFO) powders on some physicochemical properties of polyaniline (PANI) were presented and discussed. The materials were obtained by the polymerization of an aniline solution where CTFO powder, prepared by the sol-gel method was added. The microstructures of the materials were characterized using Scanning Electron Microscopy (SEM), the structure and phase composition was tested by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The electrical properties of the developed PANI-CTFO composites were determined using Electrochemical Impedance Spectroscopy (EIS). The gas sensing properties of the constructed sensor devices in the presence of water vapor were tested by measurements of DC electrical conductivity changes as a function of water vapor partial pressure. The current-voltage (I-U) characteristics were also used to characterize the influence of CTFO material on PANI electrical properties. It was found that the introduction of CTFO into the PANI host material leads to substantial changes in the material properties comparing to unmodified PANI. The discussion concerning the influence of the used modifiers on the structure, microstructure and electrical and sensing properties of the developed materials and observed correlation is also presented. The mechanism of the observed influence of CTFO on PANI properties is also proposed. The dominating role of the PANI-CTFO interface on the material properties is postulated.

PL

Polianilina (PANI) należy do grupy polimerów przewodzących posiadających ogromny potencjał z punktu widzenia możliwości budowy różnych urządzeń elektrochemicznych. W celu optymalizacji właściwości polimeru pod kątem określonego zastosowania, np. do konstrukcji czujników gazowych, stosuje się różne strategie modyfikacji. Wśród nich obiecującym podejściem jest utworzenie materiałów kompozytowych zawierających jako materiał bazowy PANI i jako modyfikator proszkowy materiał ceramiczny. W pracy przedstawiono wyniki dotyczące wpływu proszków CaTi0.8 Fe0.2O3 (CTFO) na niektóre właściwości fizykochemiczne polianiliny (PANI). Materiały zostały uzyskane przez polimeryzację roztworu aniliny, do których dodano proszku CTFO przygotowanego metodą zol-żel. Mikrostruktura materiałów została określona przy użyciu skaningowej mikroskopii elektronowej (SEM), strukturę i skład fazy zbadano przez dyfrakcję promieniowania X (XRD) i spektroskopii w podczerwieni z transformacją Fouriera (FTIR). Właściwości elektryczne opracowanych kompozytów PANI-CTFO wyznaczono za pomocą pomiarów metodą elektrochemicznej spektroskopii impedancyjnej (EIS). Charakterystyki sensorowe na obecność pary wodnej prototypowych czujników budowanych z otrzymanych materiałów były testowane poprzez pomiar zmian przewodnictwa elektrycznego w funkcji ciśnienia cząstkowego pary wodnej. Wykonano także pomiary charakterystyk prąd-napięcie (I-U), które wykorzystano do dodatkowego scharakteryzowania wpływ materiału CTFO na właściwości elektryczne PANI. Stwierdzono, że wprowadzenie CTFO do materiału bazowego PANI prowadzi do znacznych zmian właściwości materiału w porównaniu do niezmodyfikowanej polianiliny PANI. Przeprowadzono dyskusję dotyczącą wpływu stosowanych modyfikatorów CTFO na strukturę, mikrostrukturę i właściwości elekftryczne badanych materiałów na bazie PANI oraz określono wzajemne korelacje. Uzyskane wyniki wskazują na dominującą rolę granic faz CTFO-PANI na właściwości elektryczne badanych materiałów.

16

Preparation of polyaniline nanostructures doped with different dicarboxylic acids through template-free method

Sun C, Wang Y.

Materials Science Poland

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2014

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Vol. 32, No. 3

419—422

EN

Department of Materials Chemistry, Yinuo Institution, Changchun, 130033, China In this article nanoscaled polyanilines (PANI) were prepared based on template-free method in the presence of dicarboxylic acid dopants (e.g. D-tartaric acid, succinic acid, maleic acid and fumaric acid). The trans-cis isomerization of butenedioic acid played an important role in the formation of nanostructures from the plane-like to nanofibers, and the PANI doped with maleic acid (MA) had larger diameter, higher crystallinity and conductivity than PANI doped with fumaric acid (FA).

17

Factors influencing preparation of polyaniline doped with hydrochloric acid

Chuanyu S, Yu W.

Materials Science Poland

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2014

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Vol. 32, No. 4

521--525

EN

Factors influencing the reaction of chemical polymerization during aniline doping with hydrochloric acid (HCl) have been studied in this work. The optimal parameters for the preparation of polyaniline were determined as follows: aniline concentration – 4 mass %, molar ratios of oxidant (NH4)2S2O8:aniline – 1.2:1 and 1.3:1, the concentration of dopant – 1 mol/L. Fourier transform infrared spectroscopy (FT-IR) was applied to characterize the structure of polyaniline.

18

Preparation of network π-conjugated copolymers with Ullmann type polycondensation

Nakajima K., Goto H.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 6

33--38

EN

Ullmann type polycondensations in the presence of CuI and a base were carried out to afford network type π-conjugated copolymers. Infrared absorption spectroscopy measurements and surface observation using a scanning electron microscopy are carried out. Electron spin resonance spectroscopy measurements revealed that the cross-linked copolymers thus obtained contain small amount of copper. This polymerization conveniently allows production of network π-conjugated polymers. The polymer can be expected to have thermo-resistance.

19

Modyfikowana polianilina jako materiał termoelektryczny

Zawadzka E., Mazurek B.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 8

225--227

PL

Polianilina (PANI) to polimer przewodzący, który może być stosowany jako termoelement. Właściwościami tworzywa sterować można poprzez dobór metody syntezy, zmianę parametrów procesu oraz modyfikację chemiczną. W pracy zwrócono uwagę na wpływ składu chemicznego materiału na bazie polianiliny na właściwości termoelektryczne. Zmierzono przewodność elektryczną i współczynnik Seebeck’a. Przebadano wpływ kwasu solnego i kamforosulfonowego oraz wypełniaczy proszkowych (Bi, C) na właściwości termoelektryczne.

EN

Polyaniline (PANI) is an intrinsically conducting polymer and can be used as a thermocouple. It is possible to control properties of the polymer through the choice of synthesis method, its parameters or the chemical modification. In this work, authors attention has focused on the impact of the chemical composition on the thermoelectric properties of PANI-based materials. Conductivity as well as Seebeck coefficient were measured. Hydrochloric and camphor sulfonic acid or powder fillers (Bi, C) were tested.

20

An ammonia sensor based on in situ-synthesized polyaniline nanostructures

Dobroczyńska J I, Grabas K

Materials Science Poland

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2013

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Vol. 31, No. 1

95--100

EN

Nowadays, a good deal of research is focusing on the development of new analytical procedures for detection of hazardous agents, such as bacteria, harmful pollutants, toxic vapors, and many others. The majority of the research is aimed at developing new sensors and analytical equipment. This paper demonstrates a simple construction of an ammonia sensor based on commercially available electronic connectors with active elements from polyaniline. The main goal of this research is to present the simplicity of sensor manufacturing, without the need for advanced apparatus such as electropolymerization or electrospinning set-up. The active element of the proposed sensor is composed of polyaniline synthesized in situ on the surface of conductive glue. The layer of the conductive glue is a key element in this sensor as it protects the metallic pin against destruction during in situ synthesis of polyaniline (acidic and oxidizing conditions).