The influence of reduction temperature on the electromechanical properties and actuation behavior of polydimethylsiloxane (PDMS) dielectric elastomer containing the thermally reduced graphene oxide (rGO) with different surface chemistry has been systematically investigated. A set of rGO nanosheets was prepared by thermal reduction of graphene oxide (GO) at four temperatures (150, 200, 300, and 400 °C). The dielectric permittivity, dielectric loss, and elastic modulus of PDMS composites were increased, while the electrical breakdown strength of composites was decreased with an increase of the reduction temperature of GO. A thermodynamic model applied for studying the electromechanical deformation and stability of PDMS/GO­(rGO-x) dielectric elastomer composites showed that the optimum value of the break-point was observed in PDMS/rGO-300. It is shown for the first time that the variation of electromechanical instability and recovery behavior are attributed to the surface chemistry of rGOs. A critical reduction temperature is observed at 300 °C which can be considered as proper rGO nanosheets for electromechanical applications. By employing an equivalent circuit on impedance spectroscopy, the interfacial polarization is recognized as the dominant mechanism rather than the intrinsic polarization of the matrix and nanosheets. Noteworthy, PDMS composites containing rGO, reduced at higher temperatures, have more interfacial polarized charges at the interface.

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The present study discusses the effects of graphenic particles on the kinetics of sulfur vulcanization in styrene butadiene rubber composites. Using data obtained from a cure rheometer and fitted by an autocatalytic model, it was verified that graphenic particles follow our recently established catalyticnetworking model for the effect of particles on the sulfur vulcanization of rubber, regardless of the type of particles. The magnitude of the catalytic and networking effects depends on surface chemistry and interfacial interactions of particles with rubber that can be tailored by the chemical reduction of graphene oxide. Accordingly, the reduction process decreased the catalytic effect due to the elimination of surface functional groups and increased the networking effect due to the enhancement of filler-rubber interactions and immobilization of rubber. The latter was verified by differential scanning calorimetry and bound rubber measurements.

Organic resorcinol formaldehyde aerogels with distinct pore sizes/surface areas in different ratios of (resorcinol/catalyst) R/C = 300, 400, 600 and (resorcinol/water) R/W = 2 were prepared utilizing sol–gel technique and in‐situ modified by incorporating 1 wt% meta‐phenylenediamine. The porous nanostructure, surface area, and pore size of the aerogels were characterized by scanning electron microscopy, Brunauer–Emmett–Teller, and Barrett–Joyner–Halenda techniques. Raman spectroscopy, Fourier transform infrared spectroscopy, and X‐ray diffraction were employed to get understanding into the chemical structure. Furthermore, we investigated the removal percentage of antibiotic via UV–vis spectroscopy. The ability of modified aerogels in removing chlortetracycline (CTC) at different pH values (2–12), contact times (2–24 h), initial concentrations of CTC (50–100 mg L−1), and the adsorbent dose (2–10 mg) was evaluated. Consequently, the adsorption optimum conditions were found, the adsorption isotherms were measured, and isotherm models were fitted to the results to interpret the kinetics of adsorption. The obtained fitting parameters using the pseudo‐second‐order model revealed a well alignment with the experimental data. Finally, we demonstrated that the modified‐aerogels have a high capacity in CTC antibiotics removal up to 90% and an adsorption capacity of 440 mg g−1 as well as an efficient regeneration capacity for five consecutive cycles without significant degradation of the adsorption properties.