Cyclic Voltammetry, Impedance Measurements and In-Situ EPR Studies of Conjugated Polymers

Poly(2-methyl aniline) or poly(ortho-toluidine), as ring substituted derivative of aniline, has been synthesized electrochemically in various concentrations of H2SO4 and HCl, and then characterized by cyclic voltammetry, as well as by impedance and Raman spectroscopy. The cyclic voltammograms of poly(o-toluidine) and poly(aniline) show that the electrochemical polymerization of these two polymers proceeds by almost identical mechanisms. The Raman spectroscopical measurements suggest that the redox reactions of poly(aniline) and poly(o-toluidine) are similar in the potential range between -0.2 and 0.7V vs. SCE. The impedance measurements showed that the conductivity of poly(o-toluidine) is an order of magnitude lower than that of the corresponding poly(aniline) form.

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Electrochemical analysis of water and suds by impedance spectroscopy and cyclic voltammetry

Journal of Sensors and Sensor Systems ◽

10.5194/jsss-3-133-2014 ◽

2014 ◽

Vol 3 (2) ◽

pp. 133-140 ◽

Cited By ~ 3

Author(s):

R. Gruden ◽

A. Buchholz ◽

O. Kanoun

Keyword(s):

Water Quality ◽

Cyclic Voltammetry ◽

Impedance Spectroscopy ◽

Electrochemical Analysis ◽

Total Hardness ◽

Impedance Measurements ◽

Washing Process ◽

Calcium Magnesium ◽

The Ideal

Abstract. Optimum detergent dosage during a washing process depends on water quality, degree of pollution and quantity of laundry. Particularly, water quality is an important factor. Other parameters like carbonate- or non-carbonate hardness and calcium / magnesium (Ca / Mg) ratio in addition to total hardness of water have an impact on the amount of detergent. This work discusses the possibilities realizing a detergent sensor that measures important parameters for the washing process and assess the ideal necessary amount of detergent during the washing process. The approach is to combine impedance spectroscopy with cyclic voltammetry in order to determine both water quality and concentration of detergent in the suds which build up the basis for an optimum detergent dosage. The results of cyclic voltammetry show that it is possible to identify the Ca / Mg ratio and the carbonate hardness separately, which is necessary for the optimization of the washing process. Impedance measurements identify total hardness and detergent concentrations.

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Light Directs Monomer Coordination in Catalyst-Free Grignard Photopolymerization

10.26434/chemrxiv.14699979.v1 ◽

2021 ◽

Author(s):

Eliot Woods ◽

Alexandra Berl ◽

Leanna Kantt ◽

Michael Wasielewski ◽

Brandon E. Haines ◽

...

Keyword(s):

Conjugated Polymers ◽

Radical Anion ◽

Elevated Temperatures ◽

Spectroscopic Studies ◽

Computational Investigation ◽

Catalyst Free ◽

Active Layers ◽

End Groups ◽

Type Coupling

π-Conjugated polymers can serve as active layers in flexible and lightweight electronics, and are conventionally synthesized by transition-metal-mediated polycondensation at elevated temperatures. We recently reported a photopolymerization of electron-deficient heteroaryl Grignard monomers that enables the catalyst-free synthesis of n-type π-conjugated polymers. Herein we provide an experimental and computational investigation of the mechanism of this photopolymerization. Spectroscopic studies performed in situ and after quenching reveal that the propagating species is a radical anion with halide end groups. DFT calculations for model oligomers suggest a Mg-templated SRN1-type coupling, in which Grignard monomer coordination to the radical anion chain avoids the formation of free sp2 radicals and enables C–C bond formation with very low barriers. We find that light plays an unusual role in the reaction, photoexciting the radical anion chain to shift electron density to the termini and thus favor productive monomer binding.

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One-step process for the preparation of fast-response soft actuators based on electrospun hybrid hydrogel nanofibers obtained by reactive electrospinning with in situ synthesis of conjugated polymers

Polymer ◽

10.1016/j.polymer.2020.122590 ◽

2020 ◽

Vol 200 ◽

pp. 122590 ◽

Cited By ~ 1

Author(s):

Diego Oliveira Miranda ◽

Matheus Figueiredo Dorneles ◽

Rodrigo Lambert Oréfice

Keyword(s):

Conjugated Polymers ◽

Fast Response ◽

In Situ Synthesis ◽

Hybrid Hydrogel ◽

Step Process ◽

One Step ◽

Soft Actuators

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Photochromic dithienylethenes characterized by in situ irradiation NMR-spectroscopy and electrochemically induced responsiveness on gold substrates

Journal of Materials Chemistry C ◽

10.1039/c9tc04495g ◽

2019 ◽

Vol 7 (45) ◽

pp. 14088-14097

Author(s):

Jonas von Irmer ◽

Florian Frieß ◽

Dominik Herold ◽

Jonas Kind ◽

Christina M. Thiele ◽

...

Keyword(s):

Cyclic Voltammetry ◽

Nmr Spectroscopy ◽

Self Assembled Monolayers ◽

Gold Surfaces ◽

Gold Substrates ◽

Assembled Monolayers ◽

Self Assembled

The photochromic and electrochemical switching capabilities of two dithienylethenes with different substitutions and their self-assembled monolayers on gold surfaces are characterized by in situ NMR-spectroscopy and cyclic voltammetry.

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