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This study represents the culmination of our efforts to explore the crucial role of polyester composites in the field of biocomposites, highlighting their importance in advanced materials technologies. Our primary objective has been to thoroughly elucidate the significance of polyester composites within biocomposites, with a detailed examination of their impact on advanced material technologies. Through this research, we have meticulously investigated the properties of polyesters derived from biodegradable polymers, analyzing their intricate structure-property relationships and potential applications in bio-based production. To drive the industrial adoption of bio-based polyesters, our work emphasizes the need for developing economically viable production methodologies, exploring ecologically sustainable and effective material designs, and advocating for robust policy support to facilitate the commercialization of bio-based polyesters. We propose that future research should focus on the innovation of novel bio-based monomers as sustainable raw material sources, the design of diverse polyester structures utilizing material genome technology, and a comprehensive understanding of the degradation processes and long-term performance of bio-based polyesters. The advancement in this domain relies on interdisciplinary collaboration across materials science, engineering, and chemistry. Our findings underscore that through such interdisciplinary cooperation, a broader spectrum of bio-based polyester products can be developed, thereby expanding their industrial applications. In this context, our investigation aims to contribute to the advancement of sustainable materials and their more effective integration into future material technologies. [ABSTRACT FROM AUTHOR]

In this study, poly(n-isopropylacrylamide) (PNIPA) has been synthesized by the free-radical polymerization method using azobisisobutyronitrile the initiator. Then, nanoparticle-PNIPA composite is prepared with magnetic iron oxide (Fe3O4) nanoparticles synthesized by co-precipitation. The thermal decomposition kinetics of synthesized PNIPA and nanocoated PNIPA have been investigated. It has been observed that nanocoated PNIPA has a more stable structure at high temperatures than synthesized PNIPA. In the newly improved model equations relate to thermal decomposition kinetics, a special solution has been made with the new approach. Moreover, the calculated activation energies of the samples have been evaluated with response surface methodology (RSM). The ratios required to synthesize nanocoated-PNIPA under the optimum conditions have been determined by RSM. The activation energy of the nanocomposite obtains when 0.3170 g PNIPA is coated with 0.048 g Fe3O4 nanoparticle is determined as 127.757 kJ/mol. In other words, nanocoating has been increased the thermal stability of the synthesized composite. Poly (n-isopropylacrylamide) has been synthesized by free radical polymerization The Fe-O stretching vibration proves the existence of nanoparticle in FTIR spectra The thermal decomposition kinetics of synthesized PNIPA and Fe3O4-PNIPA nanocomposite have been evaluated by RSM. Magnetic nanoparticle reinforcement enhances the thermal stability of PNIPA [ABSTRACT FROM AUTHOR]

Spent hydrodesulfurization catalyst (HDS) is considered as the important secondary resource for Mo and Ni. The separation of Mo from HDS was usually conducted by soda roasting and water leaching, while Ni remained in the leached residue. This study proposed a method to recover Ni from leached residue by H2SO4 leaching and solvent extraction, and Ni was recycled in the form of NiO. The results showed that the optimum Ni leaching process were conducted using 30% H2SO4 with liquid–solid ratio of 10 at 70 ℃ for 120 min. The optimal extraction was accomplished using 30% di-(2-ethylhexyl) phosphate (P204) saponification at pH value 6.0 with organic/aqueous (O/A ratio) of 1 for 1 min. Additionally, 20% H2SO4 could be used to strip Ni from organic phase with O/A ratio of 10. Finally, NiSO4 was calcined at 850 ℃ for 1.0 h to obtain NiO. The Ni leaching kinetic analysis showed that the activation energy of Ni leaching process was 16.10 kJ/mol, which was accorded with the shrinkage unreacted kernel model controlled by internal diffusion. This study provided an alternative method to recycle Ni and given a deeper insight to the leaching mechanism during H2SO4 leaching Ni from spent catalyst. [ABSTRACT FROM AUTHOR]

Many fillers are employed as reinforcement in polymeric materials to improve their properties and reduce expenses. This research aims to improve the mechanical and thermophysical properties of waste polyethylene terephthalate (WPET). Using recycled materials is also one of the study's objectives in support of environmental preservation. Glass fiber (3 wt.%, 6 wt.%, 9 wt.%, and 15 wt.%), calcium carbonate (5 wt.%, 15 wt.%, and 25 wt.%), and corn starch (3 wt.%) have all been added to WPET in different ratios to create composite materials. The mechanical strength, Shore D hardness tests, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, and thermal, mechanical, physical, and chemical properties of these composites have all been investigated. It has been shown that while the amount of starch in the samples remains constant, the hardness increases as the amount of calcite and glass wool increases. The thermal conductivity does not significantly change as the ratio of glass fiber increases, notwithstanding a modest drop Nonetheless, the thermal conductivity values rise in tandem with the calcium carbonate (CaCO3) ratio. [ABSTRACT FROM AUTHOR]

In this research, hollow inorganic microsphere (Q-cel) reinforced unsaturated polyester composite is produced, and its thermophysical properties have been characterized. The thermal decomposition kinetics of the composite obtained at different heating rates and various compositions are modeled using artificial neural networks. Also, the production optimization of the polyester composite has been evaluated using response surface methodology. The study has been repeated for certain heating rates (5, 10, and 20 K/min). Activation energies of polyester composites have been calculated using thermogravimetric data and kinetic methods. Changes in activation energy during the thermal decomposition (4 wt.% Q-cel, 94 wt.% UP, 580–660 K, and 20 K/min) of the composite are compared using FWO (129.4 kJ/mol), KAS (127.6 kJ/mol), and CR (126.5 kJ/mol). According to the results, it is seen that the activation energy goes up as the temperature and Q-cel ratio by the mass increase. When the amount of the filler in the polyester composite increases, the thermal conductivity coefficient also rises. As well as, it is determined that as Q-cel ratio in the mixture raises, the density of the composite decreases and Shore D hardness goes up. A new and original composite has been produced with Qcel-reinforced unsaturated polyester. The density of the composite is low, its thermal stability is high, and its easy processability will provide a great convenience. Modeling the Qcel ratio of the composite with RSM and the activation energy with ANN have been provided fast, efficient and optimum results. With the composite obtained, both lightweight and thermally stable polymer materials will be produced. [ABSTRACT FROM AUTHOR]