Journal of Applied Nanomaterials and Smart Polymers
Volume:1 Issue: 2, Summer 2023

Water absorption characteristics of composite materials and gel coats are crucial for their applications in marine industry. The physical and mechanical properties of composite parts are influenced by moisture. Water absorption of five gel coat compositions based on epoxy vinylester resin and neopentylglycol unsaturated polyester resin and their blends was studied in this work. The influence of nanographene addition on the water absorption of these gel coats was also investigated. The results showed that epoxyvinylester resin had the lowest and neophentylglycol unsaturated polyester resin had the highest water absorption levels, and their blends, as expected, showed the same behavior. TEM, SEM and XRD were used to analyze and characterize the dispersion and distribution of nanographene particles in the polymer matrices. The results showed both dispersed and non-dispersed flakes in the polymer matrices. It was also shown that the addition of nanographene resulted in gel coats with lower water absorption levels.

In the academic and industrial sectors, there has been a significant level of attention directed towards novel surfactants, particularly nano gemini surfactants, owing to their distinctive characteristics in recent times. The utilization of the quasichemical approximation has enabled the determination of phase equilibrium and the mixing properties for solutions of this nature. The Helmholtz free energy, mixing entropy, and mixing energy were ascertained through the variation of hydrophilic and hydrophobic units in nano gemini surfactants. The augmentation of the hydrophilic properties of the nano gemini surfactant has been observed to enhance the reaction of mixing. In turn, there is a reduction in the energy required for mixing. Furthermore, the negative value of the Helmholtz free energy of mixing has been observed to increase. When the hydrophobicity of a nano gemini surfactant increases, a contrary result to previous findings is observed. The mixing entropy remains unaffected by the hydrophobic and hydrophilic units of the nano gemini surfactant. An increase in the hydrophobic tail length of the surfactant leads to a corresponding increase in the two-phase equilibrium region. Conversely, a decrease in the hydrophobic tail length results in a decrease in the two-phase equilibrium region.

An extensive review of the literature showed that both graphene and Cloisite 30B nanosheets are widely employed to modify the crystalline structure and piezoelectic properties of polyvinylidene fluoride (PVDF). Due to the similarity in the geometry of these nanoparticles a comparative study is reported to find the stems of difference in their effects on crystalline structure of PVDF. Scanning electron microscopy (SEM) of these composites showed that large and wide graphene particles are dispersed in PVDF matrix whereas their thickness is well below 100 nanometers. Meanwhile, a careful inspection of SEM micrographs of Cloisite 30B loaded composites revealed existence of smaller particles with almost the same particles thicknesses. Both techniques of Fourier transform infrared (FT-IR) spectroscopy and wide angle X-ray diffraction (WXRD) witnessed changes in the crystalline structure of PVDF. The overall finding was that Cloisite 30B improves the polar beta phase of PVDF crystals, whereas a revers effect was found in the presence of graphene nanosheets. These observations were accounted for by differences in surface geometry and surface free energy (surface tension and interfacial tension). Based on the data available for surface properties of these two nanosheets it was found that surface properties of Cloisite 30B is very close to those of PVDF, whereas the surface properties of graphene are far from those of PVDF. Also a lower interfacial tension was found to be active in PVDF-Cloisite 30B system compared to that operative in PVDF-graphene system. An intimate interface along with proper surface texture led to higher content of PVDF’s beta crystals in case of Cloisite 30B nanocomposite

Tire recycling or tire recycling is a process in which car tires are no longer worn out or are no longer suitable for use because of a rupture or unrepairable failure. These tires are among the most significant waste that is very problematic. This problem is due to the persistence and persistence of tires and their high volume of production. It is estimated that 259 million tires are discarded each year. In this research, the Preparation stages of production of activated carbon nanofibers produced from the recycling of worn tire rubber with different percentages of different solvents of potassium hydroxide, ethanol, and toluene were studied and tested. To achieve a solution for worn tire tires, a certain amount of scraped rubber fragments was dissolved in potassium hydroxide, ethanol, and toluene solvents, and electrospinning solutions were determined and prepared and to produce nanofiber layers, Electrospinning operations are performed. By scanning electron microscopy images, the mean diameter of nanofibers obtained in potassium hydroxide solvent was the lowest, and scanning electron microscopy images confirmed the absence of willow in the produced nanofibers. The efficiency of carbon production was determined as 37.2%. To confirm the formation of activated carbon, FTIR spectra were used, which confirmed the presence of spike related to the aromatic ring formation of activated carbon nanofibers after activation.

A promising and reusable nanohybrid based on carbon quantum dots (CQD) was fabricated as a sorbent for ultrasound- and magnetic-assisted dispersive micro-solid-phase extraction(US-M-A-DMSPE) followed by high-performance liquid chromatography with ultraviolet detection (HPLC-UV) for simultaneous trace determination of cephalosporins (Cefdinir & Cefixime) in human plasma. The structure of the prepared sorbent was characterized by x-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Under the optimized conditions, the nanosorbent provided high adsorption and selectivity toward the analytes. The limits of detection and the coefficients of determination (r2) with dynamic ranges for cefdinir & cefixime were estimated. The method was used for quantifying cefdinir & cefixime in plasma samples to evaluate the pharmacokinetic aspects,including the half-life (T1/2), the time to reach the maximum concentration (Tmax), the maximum plasma concentration (Cmax), area under the curve (AUC0-24) and area under the curve at infinite time (AUC0-∞). Reliable reproducibility as the intra- assay and inter-assay together with reasonable accuracy were obtained.