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Polyvinylidene fluoride and polyvinylpyrrolidone polymers incorporated with carbon black nanoparticles (50 nm) were electrospun to fabricate nanofibrous membranes for supercapacitor separators. Different weight percentages (0, 0.25, 0.5, 1, 2, and 4 wt %) of carbon black nanoparticles were dispersed in N,N-dimethylacetamide and acetone prior to the electrospinning processes at various voltage, pump speed, and tip-to-collector distances. The morphology, thermal, mechanical, hydrophobic, and electrochemical characterization of nanofibrous membrane were analyzed using different techniques, such as scanning electron microscopy, differential scanning calorimetry, capacitance bridge, thermogravimetric analysis, dynamic mechanical analyzer, and water contact angle. Effects of annealing and UV irradiation exposures on the nanofibrous membranes were investigated in detail. Test results revealed that the physical properties of the nanocomposite separators were significantly enhanced as a function of carbon black inclusions in the polymeric structures, which may be useful for the applications of supercapacitor separators and other energy storage devices.

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Carbon nanotubes (CNTs) with straight geometries have been widely studied for various engineering applications, and they are often treated or functionalized to improve their effectiveness, depending on their role and expected performance. However, helical configurations of CNTs (HCNTs) have not been sufficiently investigated, especially in their functionalized states for high-performance nanocomposite applications. The coil-shaped geometry of these HCNTs increases the mechanical entanglement of these nanotubes with a host resin system when they are used as reinforcements. This consequently has the potential to improve the mechanical, thermal, electrical, and magnetic properties of the polymeric matrix systems. A uniform dispersion of CNTs in the resin plays an important role in obtaining improved and consistent properties in the final nanocomposite part. To improve the homogeneous dispersion (individual suspension) of these nanotubes in the host resin and to enhance their interactions/bonds with the resin molecules, the surface of these nanotubes should be modified. This study investigates a sonication method for chemical functionalization of HCNTs using a mixture of sulfuric and nitric acids with 3 to 1 mixing ratio [3 : 1], and it evaluates the effects of acid concentrations and sonication time on the severity of the functionalization process. To evaluate the effectiveness of the process parameters, the functionalized HCNTs (FHCNTs) were examined using several characterization instruments and techniques such as Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), X-ray Diffraction (XRD), visual dispersion test, and Raman spectroscopy. The characterization results confirmed that the changes in process parameters were mostly effective and the atomic structures of the functionalized HCNTs were successfully altered. All FHCNT samples demonstrated higher dispersion uniformity, increase in Raman ID/IG ratios, and changes in the FTIR spectra compared to the pristine HCNTs. Most of the FHCNTs had a reduction in crystallinity, which was consistent with our expectation that functionalization generates more defects on the surface structure of HCNTs, thus leading to a lower intensity of the graphitic peak. The largest reduction in crystallinity was seen for HCNTs treated with a 16 molarity acidic solution; therefore, the HCNTs that were treated with lower molarity acids could be used for further studies and explored for their effective applications in improving the mechanical, thermal, and electrical properties of polymeric nanocomposites.

This chapter discusses sustainable development (SD) planning in manufacturing facilities. The industrial sector uses half of the world's energy, and manufacturing, as the core of this sector, contributes significantly to energy consumption and environmental footprints. In this chapter, in the first step, energy consumption, as one of the main factors influencing SD in manufacturing, is analyzed from different perspectives, and its impact on SD is studied. Thereafter, several energy-aware operations management approaches are proposed. These approaches integrate energy consumption into classic production planning and scheduling decisions. In the second step, a generic sustainability-based decision-making framework is proposed for maintenance strategy selection problem, considering three pillars of sustainability. For this purpose, various indicators are proposed for each sustainability factor that has an impact on maintenance planning decisions. The maintenance strategy alternatives are evaluated for each indicator and the best alternative is selected using a decision-making method.