Synthesis and Physicochemical Properties of Poly(2-ethyl-3-methylindole)

Self-powered temperature and humidity sensing platform based on Ag2S/poly(5-carboxyindole)/hydroxyethyl cellulose nanocomposite

A self-powered dual-function temperature and humidity sensing platform is constructed based on Ag2S/poly(5-carboxyindole)/hydroxyethyl cellulose composite material (Ag2S/P5ICA/HEC). The Ag2S nanomaterial with reticular porous structure is successfully synthesized via a solvothermal method for use as electrodes in supercapacitors and temperature sensors. Then, a highly sensitive Ag2S/P5ICA/HEC-based humidity sensor is successfully prepared by drop-coating the surface of Ag2S material with P5ICA/HEC composite. The analysis results reveal that the Ag2S electrode material shows good electrochemical properties with high specific capacitance (6.11F/cm3 at 0.04 A/cm3 current density) and cycle stability. Moreover, the symmetric supercapacitor constructed based on the Ag2S electrode material also exhibits high energy storage capacity and long term cycling stability. Additionally, the Ag2S material showed temperature sensitivity, with its resistance values positively correlated with temperature in a linear relationship (R2 = 0.992). The rough and reticular porous structure of Ag2S/P5ICA/HEC provides large surface area for adsorbing more water molecules, thereby increasing the sensitivity of humidity detection. The analysis results show that the sensor is sensitive to humidity at room temperature. In the detection range of 20-80 % relative humidity (RH), the natural logarithm of the resistance response signal shows a good linear relationship with humidity (R2 = 0.996). The sensor exhibits a sensitivity of 0.078 Ω / % RH, coupled with excellent repeatability and stability. Finally, a self-powered temperature and humidity sensing platform is constructed using a symmetric supercapacitor with Ag2S electrodes as the energy storage component, and Ag2S/P5ICA/HEC composite material as the temperature and humidity sensing component. This platform exhibits excellent temperature and humidity detection capabilities and holds potential for applications in areas such as pharmaceutical storage, food storage, and agriculture.

Removal of Anionic Methyl Orange Dye from Water by Poly[2-methyl-1H-indole] Derivatives: Investigation of Kinetics and Isotherms of Adsorption

The adsorption properties toward methyl orange (MO) were evaluated for poly[2-methyl-1H-indole] and its derivatives. The influence of pH, ionic strength of solution, composition, and amount of sorbent on the adsorption of MO dye was investigated; the kinetics of dye adsorption was studied. The adsorption isotherms were analyzed using different models of sorption equilibrium. The presence of chemical interaction between polyindoles and dye was proved by IR and UV spectroscopy methods. The sorption of MO with polymers is realized mainly due to the formation of electrostatic interactions between the sulfogroup of the dye and the imino group of the sorbent. Microphotographs demonstrate the change in the morphology of polyindoles after adsorption, which further confirms the structural changes in the polymers. It was found that the main factors affecting the sorption capacity of the studied materials are the position and nature of substituents in the polymers and the sorption conditions. For example, polyindoles containing a methoxy group in their structure (o-OMePIn and m-OMePIn) have the best sorption activity. These polymers are effective in adsorbing dyes, which means that they can be used in wastewater treatment.

Photoconductivity of Thin Films Obtained from a New Type of Polyindole

The optoelectronic properties of a new poly(2-ethyl-3-methylindole) (MPIn) are discussed in this paper. The absorption and photoluminescence spectra were studied. The electronic spectrum of MPIn showed a single absorption maximum at 269 nm that is characteristic of the entire series of polyindoles. The fluorescence spectra show that the emission peaks of the test sample are centered around 520 nm. The photoconductivity of thin film samples of MPIn polyindole was studied by measuring the current-voltage characteristics under ultraviolet radiation with a wavelength of 350 nm. Samples of phototransistors were obtained, where thin films of MPIn polyindole were used as a transport layer, and their characteristics were measured and analyzed. The value of the quantum efficiency and the values of the mobility of charge carriers in thin polyindole films were estimated.

Poly[N-(2-chloroprop-2-en-1-yl)aniline]s: synthesis, polymer analogous reaction, and physicochemical properties

A series of new soluble N-substituted poly(β-haloallylanilines) were synthesized by oxidative polymerization. Based on these polymers and polyphosphoric acid, various functionalized polyindoles of a new type were obtained in high yields.

Synthesis and physicochemical properties of poly[2-(cyclohex-2-en-1-yl)aniline] as a new polyaniline derivative

A new polyaniline derivative, poly[2-(cyclohex-2-en-1-yl)aniline], was synthesized using different synthetic parameters.