Vegetable oils are alternatives to producing renewable monomers since they are biomass. It is possible to react them with anhydrides by heating to provide monomers with high reactivity. However, after the reaction of grape seed oil with itaconic anhydride, it was observed the occurrence of parallel reactions that had not been observed when the same oil was reacted with maleic anhydride. Some articles in the literature have reported that temperature and bases can isomerize itaconic anhydride into citraconic anhydride, which is more stable at room temperature. However, they have not focused on completely understanding how this phenomenon occurred nor studied it in processes that involve microwave irradiation. Therefore, this paper presents a complete characterization and investigation about the thermal behavior of itaconic anhydride and how it can affect the monomer synthesis performed under heating. biomass reactivity However irradiation Therefore

This work aims to produce and disseminate videos that follow the microlearning methodology, to explain the physicochemical properties of cobalt (II) chloride hexahydrate through thermal analysis, and to determine the reliability of the Portuguese good luck rooster. Temporal and social accelerations due to the growth of the technological world are changing the old teaching-learning methodologies; thus, new methods should be explored. In the microlearning methodology, short segments and specific content can be broadcast to anyone at any time. In addition, relating new information to individual’s experiences can favor the teaching-learning process. The good luck rooster is an ornament of Portuguese origin, which can forecast the weather in a limited way, and is composed of cobalt (II) chloride hexahydrate. This compound was characterized by TG-DTA (Simultaneous Thermogravimetry-Differential Thermal Analysis) and DSC (Differential Scanning Calorimetry), verifying that the salt loses its hydration water when exposed to high temperatures, changing its color from pink color to blue.

Abstract The surface of Fe3O4 nanoparticles is very reactive and can oxidize to γ-Fe2O3 (maghemite) and α-Fe2O3 (hematite) structures. Based on this, the oxidation process of Fe3O4 nanoparticles must be prevented, and one of the strategies is surface functionalization with organic or inorganic molecules. Thus, this study analyzed the thermal behavior of Fe3O4 and Fe3O4-EDTA nanoparticles using X-ray diffraction (XRD), simultaneous thermogravimetry-differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC). Results showed that γ- Fe2O3 was obtained as an intermediate in Fe3O4 and Fe3O4-EDTA decomposition, as confirmed by TG-DTA and DSC curves. Moreover, Fe3O4-EDTA exhibited a temperature peak (Tp = 573.5°C) of phase transformation (γ-Fe2O3 → α-Fe2O3) higher than that of Fe3O4 (Tp = 533.0°C), confirming that EDTA molecules stabilized the nanoparticles efficiently. The kinetic behavior of samples changed, and the activation energy for functionalized samples decreased.

Grape seed is a waste product from the wine and juice industries. However, vegetable oil can be extracted from it, which is a renewable chemical with a huge potential application after chemical modifications, such as epoxidation and maleinization processes. This paper therefore deals with the use of grape seed oil, to produce its epoxidized and maleinized derivatives. Both derivatives were synthesized in order to improve the conversion (99.4%), yield (98.9%) and selectivity (99.5%) values, as well as to decrease the reaction time (3 h) using cleaner energy sources and heterogeneous catalysts, which can be used 4× without regeneration and obtaining similar conversion and yield values, and at least 5× keeping high selectivity. Based on the characterization results, both grape seed oil derivatives may be applied in different fields, including polymer chemistry as a monomer, coating, and paint. In addition, they can be an option to industries that use petrochemical derivatives as precursors.

Solid-state LnL3∙nH2O complexes, where Ln stands for trivalent lanthanides (Tb to Lu) or yttrium(III) and L is oxamate (NH2COCO2-), have been synthesized. The characterization of the complexes was performed by using elemental analysis (EA), complexometric titration with EDTA, thermoanalytical techniques such as simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), evolved gas analysis (TG-FTIR), infrared spectroscopy (IR) and powder X-ray diffraction (XRPD). The results provided information about thermal behavior, crystallinity, stoichiometry, coordination sites, as well as the products released during thermal degradation of the complexes studied. Theoretical calculation of yttrium oxamate, as representative of all complexes was performed using density functional theory (DFT) for studying the molecular structure and vibrational spectrum of the investigated molecule in the ground state. The optimized geometrical parameters and theoretical vibrational spectrum obtained by DFT calculations are in good agreement with the experimental results.