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Herein, the nanofibrillated poly(butylene succinate)/polytetrafluoroethylene (PBS/PTFE) composites were prepared. The relaxation time was prolonged by PTFE fibrils, resulting in an enhancement in storage modulus and melt viscosity. Differential scanning calorimetry was used to study the non-isothermal crystallization kinetics at different cooling rates. These results showed that PTFE fibrils could promote crystallization nucleation and excessive fibrils could inhibit crystallization growth. Lightweight PBS/PTFE composite foams were fabricated using core-back foam injection molding. Loading the PTFE fibrils increased the cell density of PBS foam from 2.7×106 to 1.4×108 cells/cm3 and improved the cell morphology of PBS foam. By controlling the foaming parameter, the tensile properties of PBS-based composite foam with 1 wt.% PTFE were improved overall, and the Izod impact strength was increased by 9–69% compared with the PBS foam. [ABSTRACT FROM AUTHOR]

Jelly glue made of gelatin is frequently used in the packaging industry. The purpose of this study is to determine whether starch and polyvinyl alcohol (PVA), which were introduced at a 1.0% concentration, could be used to develop with improvement in the performance properties of jelly adhesives that are being prepared. By examining viscosities at different temperatures, pH, water contact angles, differential scanning calorimetry (DSC), tensile strength on wood and setting speed observation on coated paper, and performing pencil hardness tests on films, the effect of adding starch and PVA as a binder on physical, thermal, and mechanical properties were studied. When starch and PVA were added to the jelly glue, DSC data showed a substantial rise in the glass transition temperature, which were further confirmed by film hardness testing. The addition of starch increased the adhesive's viscosities at different temperatures. When compared to an original sample, the tensile strength with starch increased by ~ 74% after 24 h of bonding in a dry environment. The jelly adhesive with starch showed increased in water resistance which was also validated from contact angle test. Unlike PVA-based jelly glue, the hydrogen bonding in starch and gelatin showed superior mechanical properties. This research discusses starch as a potential substitute for the development of jelly adhesive. The technique developed offers an easy and useful path to adhesives with increased water resistance and bonding strength by using starch as a binder. Ecologically sound, sustainable, and economically acceptable were the methods used to increase jelly adhesive's resistance to moisture. The study's overall finding highlights the superior and sustainable adhesive performance of jelly glue based on starch as a packaging adhesive. [ABSTRACT FROM AUTHOR]

This research aims to improve the flame-retardant properties of wood–plastic composites with different recycled plastics. Acrylonitrile butadiene styrene (ABS) and polyvinyl chloride (PVC), flame-retardant materials, and recycled polypropylene (PP) were used as matrix in this research. Recycled ethylene propylene diene monomer (EPDM) with flame-retardant properties was also added to mix with rubberwood flour (RWF) to improve mechanical properties. The rubberwood flour, coupling agent (MAPP), and lubricant are fixed at 44.5%, 4%, and 1%, respectively, whereas recycled plastics and EPDM rubber contents are in the range of 30.5–50.5% and 0–20%, respectively. The composite materials were manufactured into panels using a twin-screw extruder and hot press machine. The experimental results were statistically analyzed by analysis of variance (two-way ANOVA) at a 95% confidence level. The highest values of the mechanical parameters of wood–plastic composites reinforced with recycled polypropylene (RWF44.5PP50.5) were 15.89 MPa, 42.26 MPa, 41.79 MPa, and 0.0202 J for tensile strength, flexural strength, compression strength, and impact strength, respectively. An increasing EPDM rubber content of wood–plastic composites provided better thermal properties. The thermogravimetric analysis and differential scanning calorimetry of hybrid composites with recycled ABS (RWF44.5ABS30.5EPDM20) obtained the highest value with thermal stability in the range of 255–284 °C. For the flammability properties, the hybrid composites with high EPDM rubber content were less flammable. Recycled PVC with content of RWF44.5PVC50.5 outperformed hybrid composites reinforced made from ABS and PP in terms of UL-94 and the limiting oxygen index with values of 25.73%. [ABSTRACT FROM AUTHOR]

The quality 2-amino-5-chloropyridinium 4-aminobenzoate (2A5ClP4AB) single crystals were grown in methanol solvent by employing the solvent evaporation technique. The stoichiometry ratio of 2A5ClP4AB was confirmed by microanalysis. The melting point, decomposition, crystalline phase, purity, and specific heat capacity of 2A5ClP4AB crystal were explored by thermogravimetric-differential thermal analyses (TG–DTA), differential scanning calorimetry (DSC), and modulated scanning calorimetry (MDSC) methods. The various dielectric properties of 2A5ClP4AB single crystal concerning temperature and frequency were examined by dielectric measurements. The nonlinear optical (NLO) parameters such as dipole moment, polarizability, first-order hyperpolarizability, and second-order hyperpolarizabilities of the 2A5ClP4AB molecule were computed using density functional theory (DFT) by utilizing the Gaussian 09 program. The figured HOMO–LUMO energies of 2A5ClP4AB demonstrate the occurrence of a charge transfer mechanism, whereas the MESP map illustrates how various molecular interactions took place in it. Hirshfeld surface analyses helped to decode the nature of the interactions and packing structure of the crystals. The above studies were intended to explore the structural, thermal, electrical and NLO properties of 2A5ClP4AB and also to strengthen its effectiveness for optoelectronic and frequency conversion applications. [ABSTRACT FROM AUTHOR]

The addition of metals or metal oxides (MOs) into polypyrrole (PPy) could facilitate the effective incorporation of the features of a parent component into novel nanocomposites. As such, this present study used in-situ ultrasonic-assisted chemical oxidative polymerisation (in-situ UA-COP) to synthesise MO-PPy nanocomposites using titanium dioxide (TiO2), zinc oxide (ZnO), and silicone dioxide (SiO2). The impact of MOs on the structural, morphological, thermal and electrical characteristics of the fabricated nanocomposites was then methodically analysed. The nanocomposites' structural and chemical constitutions were ascertained by way of X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. The MOs were incorporated via non-covalent bonds into the PPy matrix, without significantly affecting the PPy matrix. Thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyses demonstrated that TiO2-PPy was the most thermally stable, rending it is ideal for use in reactions that require high resistance to temperature. It also had the highest electrical conductivity (2.48 S/cm), which could be attributed to the conductive channels that the MO nanoparticle interconnections formed within the polymer matrix. This in-depth investigation serves to disclose the effect of different MOs on the characteristics of PPy nanocomposites. The findings of this present study also highlight the potential applications of the produced PPy nanocomposites in different fields, especially for use in sensors. [ABSTRACT FROM AUTHOR]

Poly(lactide acid) (PLA) foams have shown considerable promise as eco-friendly alternatives to nondegradable plastic foams, such as polystyrene (PS) foams. Nevertheless, PLA foam typically suffers from low heat-resistance and poor cellular structure stemming from its inherent slow crystallization rate and low melt strength. In this study, a high-performance PLA foam with well-defined cell morphology, exceptional strength and enhanced heat-resistance was successfully fabricated via a core-back microcellular injection molding (MIM) process. Differential scanning calorimetry (DSC) results revealed that the added hydrazine-based nucleating agent (HNA) significantly increased the crystallization temperature and accelerated the crystallization process of PLA. Remarkably, the addition of a 1.5 wt% of HNA led to a significant reduction in PLA's cell size, from 43.5 µm to 2.87 µm, and a remarkable increase in cell density, from 1.08×107 cells/cm3 to 2.15×1010 cells/cm3. This enhancement resulted in a final crystallinity of approximately 55.7% for the PLA blend foam, a marked improvement compared to the pure PLA foam. Furthermore, at 1.5 wt% HNA concentration, the tensile strength and tensile toughness of PLA blend foams demonstrated remarkable improvements of 136% and 463%, respectively. Additionally, the Vicat softening temperature of PLA blend foam increased significantly to 134.8 °C, whereas the pure PLA foam exhibited only about 59.7 °C. These findings underscore the potential for the preparation of lightweight injection-molded PLA foam with enhanced toughness and heat-resistance, which offers a viable approach for the production of high-performance PLA foams suitable for large-scale applications. [ABSTRACT FROM AUTHOR]

Fe-based amorphous alloys are an eco-friendly alternative to Ni- and Co-based amorphous alloys, which are not sustainable. Herein, amorphous Fe–P alloys were electrodeposited from an eco-friendly aqueous electrolyte. The influence of bath temperature on the electrochemical behaviour during Fe–P alloy deposition was investigated using linear-sweep voltammetry, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. The morphology, P content and phase structure were characterized via scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and differential scanning calorimetry. The electrochemical corrosion behaviour in 3.5 wt% NaCl solution was studied using potentiodynamic polarization curves and EIS spectra. The results showed that an increase in bath temperature leads to a positive shift in the inductive co-deposition potential and increases the reaction rate. At bath temperatures of 20–60°C, the P content in deposits varied in the range of 17.07–21.13 wt% and the phase structure was amorphous. Although the amorphous alloys lacked crystalline defects, the P content had a marginal effect on the corrosion properties, whereas the surface morphology significantly influenced the corrosion properties. The amorphous Fe–P alloys fabricated in this study exhibit superior corrosion properties to almost all electrodeposited amorphous alloys reported in the literature, demonstrating their potential for corrosion protection. [ABSTRACT FROM AUTHOR]

Repercussion of overutilizing the fossil fuels and petrochemicals resulted in global warming and polluted environment. Hence, in the quest for alternative sources of raw materials for developing greener adhesives, renewable and natural polymers like polysaccharides have a huge potential. In particular, the traditional water-based emulsion wood adhesive employs colloid-like polyvinyl alcohol for stabilizing polyvinyl acetate (PVAc) emulsion. Researchers have recently become interested in utilizing xanthan gum, a naturally occurring polymer, in place of stabilizers. Here, the effects of xanthan gum addition as a stabilizer for PVAc homopolymer-based wood adhesives on performance properties were investigated. Emulsion polymerization technique was employed to synthesize xanthan gum stabilized PVAc homopolymer emulsion. Hence, the present work investigates the applicability of xanthan gum added 0.5% and 1% as a colloid for the synthesis of PVAc wood adhesives. Effect of the addition of xanthan gum as a colloid on physical, thermal, and mechanical properties was studied by viscosity, pH, contact angle measurement, differential scanning calorimetry (DSC), and pencil hardness test of films. Emulsions in varying xanthan gum concentrations were prepared, and a universal tensile machine was utilized to measure the shear strength of the PVAc homopolymers applied to wood. As the concentration of xanthan gum increased, the adhesives' viscosity increased. The drastic increase in water resistance with increasing xanthan gum content was confirmed by water contact angle measurement. The use of xanthan gum improved the PVAc films' hardness as well. When compared to a pristine sample, the tensile shear strength with 1 wt% of xanthan increased by 50% after 6 h of bonding in dry environment and by 61% in wet conditions (as per EN 204). The study's overall conclusion highlights the enhanced adhesive performance of xanthan gum stabilized PVAc emulsion-based adhesives. [ABSTRACT FROM AUTHOR]

In this work, isotactic polypropylene (iPP) was modified with an organic phosphate salt nucleating agent LPN-9081 and CaCO3. The synergistic effect of LNP-9801 and CaCO3 in iPP was investigated using differential scanning calorimetry (DSC), scanning electronic microscope (SEM), and mechanical property tests. The DSC results showed that the peak crystallization temperature (Tc) of modified iPP was increased by about 10 °C when compared to that of pure iPP, this indicates that LNP-9801 and CaCO3 increased the crystallization rate of iPP. The mechanical property tests demonstrated significant improvements in bending modulus and impact strength of modified iPP (impact strength increased by 33.9%, flexural modulus increased by 100.1%), which achieved an optimal balance of stiffness and toughness. Furthermore, the SEM results indicated that LPN-9081 contributed to the good dispersion of CaCO3 in the iPP matrix. All of the above results show that organic phosphate salt nucleating agent LPN-9081 and CaCO3 had good synergistic effects in iPP. [ABSTRACT FROM AUTHOR]

The object of the present study is to develop a new controlled drug release system by loading quercetin into pluronic F127 micelles. For the experimental studies, first of all, the critical micelle concentration (CMC) of the pluronic F127 copolymer was found as 4.5% g/mL at 25 °C, since the micelle-forming surfactants formed micelles at concentrations equal to or higher than the CMC. Afterward, with thin-film hydration method, three micelle groups with different polymer/quercetin ratios were formed. In this procedure, pluronic F127 polymer dissolved in ethanol at 30–40 °C and different amount of quercetin was added to the polymer solution. The polymer-quercetin solutions were evaporated in the evaporator at 40 °C for 2 h to obtain a film. The resulting film was hydrated by adding of ultrapure water and the micelle suspensions were obtained after filtration. According to Malvern Zetasizer measurement and transmission electron microscope (TEM) analysis, quercetin loaded micelles were determined to have particle sizes between 40 and 50 nm. It was determined by fourier-transform infrared spectroscopy (FTIR) analysis that quercetin was physically found into pluronic F127 micelles without any chemical reaction. It was determined by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analyzes that quercetin was present in amorphous form as a solid solution instead of in crystalline form in the micelles. Thermogravimetric analysis (TGA) analysis showed that loading quercetin into the micelles did not affect the thermal stability of the PF127 copolymer. The drug loading amounts for micelles were found between 1.95% and 3.3% (mg/mg) for different micelles groups and there was not much difference in the percentage of encapsulation efficiency values thought to the groups. In vitro release profiles of quercetin-loaded micelles were investigated in pH 7.4 phosphate buffer solution and at 37 °C. When the release results were examined in general, it was seen that the release rates of all formulations were almost the same after 168 h. The kinetic parameters of the release results of the micelles in different formulations were calculated according to the Peppas equation and it was determined that the quercetin release in each micelle formulation did not comply with Fick's law, according to the calculated n parameter. Quercetin-loaded polymeric micelles obtained in this study offer advantages due to their easy synthesis methods and slow release profiles and they can used to successfully encapsulation of hydrophobic active ingredients like quercetin. [ABSTRACT FROM AUTHOR]

High thermostability and catalytic efficiency of α-amylase are required for the industrial applications. To improve catalytic parameters including Michaelis constant, maximum velocity, turnover number, enzyme half-life, and the catalytic efficiency of α-amylase, it was treated alone and/or simultaneously with Ca2+ ions (12.5 and 25 mM) and/or ultrasound (USN) (64.5 W, 25 + 40 kHz). The structural analysis of the enzyme (the enzyme's secondary structure and conformation) was carried out using Fourier transform infrared (FTIR) spectroscopy and circular dichroism (CD) techniques. Moreover, the thermal properties of the enzyme were evaluated using differential scanning calorimetry (DSC). USN + 12.5 mM Ca2+ and 25 mM Ca2+, changed the maximum velocity (+ 6.5% and + 37.4%), turnover number (+ 6.6% and + 38.2%), enzyme half-life (+ 51.6% and + 113.7%), and catalytic efficiency (+ 18.1% and -3.3%) of α-amylase. The energy barriers of thermo-inactivation and inactivation enthalpy of α-amylase exposed to USN + 25 mM Ca2+ were increased by 25% and 5.8%, respectively, without affecting entropy of inactivation, showing how enzyme's thermal stability was improved after the treatments. The increase in midpoint temperature (35%) and α-helix (14%) values as well as the decrease in the β-sheet structure (39%) of the α-amylase after applying USN + Ca2+ (25 mM) confirmed the thermal stability enhancement of α-amylase after the treatment compared to control. [ABSTRACT FROM AUTHOR]

A new single crystal of p-aminomethylbenzoicdichloride hydrate C8H10NO2·Cl·H2O (Compound1) was obtained by slow evaporation. The structure was investigated by single-crystal X-ray diffraction which revealed that they crystallize in monoclinic, P2/c system space group and unit cell parameters: (a = 15.957(5) Å, b = 4.823(5) Å, c = 12.154(5) Å, β = 107.562(5)° and Z = 4). The asymmetric unit consisted of a combination of a chlorine ion−anion, one structural water molecule H2O and an organic cation [+NH3–CH2–C6H4CO2H]. The structural integrity is upheld through an intricate three-dimensional hydrogen network, serving as a stabilizing force for the crystal lattice. The cohesion between organic chain and chlorine Cl− anion and H2O molecule is assured by π-stacking and hydrogen bonds interactions N–H...Cl, N–H...OH2 and C=O...H–O–C. The interaction has been thoroughly examined using Hirschfeld surface analysis. Furthermore, we employed density functional theory calculations to optimize the molecular structure. The micro-Raman spectroscopy measurements were taken to elucidate the vibration modes exhibited by the compound. Additionally, the material characteristic was probed using a deferential scanning calorimetry. [ABSTRACT FROM AUTHOR]

Cyclosporine A (CyA) holds significant importance as a strategic immunosuppressive drug for organ transplant patients. In this study, we aimed to produce pure and cost-effective Cyclosporine A (CyA) by fermenting a culture medium containing dairy sludge, using Tolypocladium inflatum PTCC 5253. Following the fermentation stage, ethyl acetate extraction and fast protein liquid chromatography were employed for sample purification. The initial evaluation of the effectiveness of CyA obtained from these processes was performed through bioassay, wherein the antimicrobial clear zone diameter was found to be larger compared to the sample obtained from the fermentation culture. The concentration of CyA was determined using high-performance liquid chromatography, yielding values of 334 mg/L, 456 mg/L, and 578 mg/L for the fermented, extracted, and purified samples, respectively. Further analysis utilizing liquid chromatography tandem mass spectrometry (LC/MS/MS) confirmed a purity of 91.9% and proper agreement with the standard sample based on the ion intensity of Z/m 1205. To validate the structure of CyA, nuclear magnetic resonance spectroscopy, Fourier-transform infrared (FT-IR), and Raman spectroscopy were employed. X-ray diffraction and differential scanning calorimetry analyses demonstrated that the purified CyA exhibited a crystal structure similar to the standard sample, characterized by two broad peaks at 2θ = 9° and 20°, and comparable glass transition temperatures (57–68 °C for the purified sample; 53–64 °C for the standard sample). Dynamic light scattering analysis confirmed a uniform particle size distribution in both the purified and standard samples. The zeta potentials of the purified and standard samples were determined to be − 25.8 ± 0.16 and − 23.63 ± 0.12 mV, respectively. Our results demonstrate that dairy sludge can serve as a suitable culture medium for the production of (CyA). [ABSTRACT FROM AUTHOR]

Although a low temperature limit for life has not been established, it is thought that there exists a physical limit imposed by the onset of intracellular vitrification, typically occurring at ~−20 °C for unicellular organisms. Here, we show, through differential scanning calorimetry, that molar concentrations of magnesium perchlorate can depress the intracellular vitrification point of Bacillus subtilis cells to temperatures much lower than those previously reported. At 2.5 M Mg(ClO4)2, the peak vitrification temperature was lowered to −83 °C. Our results show that inorganic eutectic salts can in principle maintain liquid water in cells at much lower temperatures than those previously claimed as a lower limit to life, raising the prospects of active biochemical processes in low temperature natural settings. Our results may have implications for the habitability of Mars, where perchlorate salts are pervasive and potentially other terrestrial and extraterrestrial, cryosphere environments. A differential scanning calorimetry study of Bacillus subtilis vitrification shows that perchlorate salts can lower the onset of intracellular vitrification, with implications for the low temperature limit of life in salt-rich subzero environments. [ABSTRACT FROM AUTHOR]

Epoxy acrylate is produced by esterifying epoxy resin and acrylic acid through a ring-opening reaction. This process is highly exothermic and can be challenging to control gel formation. The thermal hazards of epoxy acrylate preparation were evaluated in this study by investigating the ring-opening esterification reaction between acrylic acid (AA) and bisphenol A epoxy resin (E-51) catalyzed by triethylamine (TEA). The heat release during the reaction process was analyzed using a reaction calorimeter (RC1mx) to simulate industrial conditions. Increasing the TEA catalyst content from 0.3 to 1.0 mass% resulted in a significant rise in reaction conversion from 75.35 ± 0.10% to 98.44 ± 0.10%. Differential scanning calorimetry (DSC) and accelerating rate calorimeter (ARC) were used to examine the thermal runaway process during epoxy acrylate synthesis. Increasing the TEA content from 0.3 to 1.0 mass% decreased the initial reaction temperature from 60.16 ± 0.62 to 45.33 ± 0.40 °C and the critical temperature of side reactions from 153.71 ± 1.51 to 117.85 ± 1.19 °C. The severity of the runaway was classified as medium at process temperatures of 80–110 °C. This study highlights the importance of considering reaction conditions to prevent uncontrolled reactions during epoxy acrylate synthesis, providing valuable insights for industrial epoxy acrylate preparation. [ABSTRACT FROM AUTHOR]

Methylene diphenyl diisocyanate (MDI) serves as a primary component of polyurethane in various applications, including household appliances, architectural structures, automobiles, and adhesives. A recent MDI plant explosion in China highlighted the importance of studying MDI's thermal stability and parameters to prevent accidental thermal decomposition. In this study, an extensive array of analytical techniques, including differential scanning calorimetry, thermogravimetric analysis, and adiabatic accelerating calorimeter, was employed to determine the thermokinetic constants of MDI, providing a solid foundation for further in-depth investigations. The findings revealed that MDI containing water reacts at substantially lower temperatures, while pure MDI can release heat and gases in an adiabatic environment, posing a considerable explosion risk. The kinetic constant of MDI was calculated using the Flynn–Wall–Ozawa method, yielding apparent activation energy values ranging from 51.78 to 96.70 kJ mol−1 across a conversion degree range of 0.05–0.70. The Coats–Redfern model pinpointed the kinetic reaction mechanism as a two-stage chemical process based on the apparent activation energy. Molecular optimization, following the energy minimisation principle, was conducted using Gaussian 09 software, which led to the identification of the optimal pathway for generating carbodiimide and carbon dioxide. This investigation offers valuable insights for the effective management of MDI during production, transportation, and storage, contributing to improve loss prevention practices in the industry. [ABSTRACT FROM AUTHOR]

Precipitation processes in age hardenable aluminium alloys are often investigated by differential scanning calorimetry (DSC). The endothermic and exothermic peaks of the DSC signal correspond to the dissolution and formation of phases, respectively. However, parasitic effects can lead to an unintended curvature of the DSC signal. Although a baseline correction can be used, some imperfections typically remain. Additionally, sample preparation and experimental conditions can influence the precipitation sequence itself and, therefore, the DSC curve. In this study, we investigate the influence of sample preparation by milling and punching on DSC curves for three different aluminium alloys: EN AW-2024, EN AW-6082, and EN AW-7075. Additionally, the influence of quenching and natural ageing was investigated for EN AW-6082. We found that deformation introduced by punching the DSC samples with a piercing die after heat treatment leads to a change in the precipitation kinetics in 2xxx, 6xxx, and 7xxx series alloys. The influence was strongest for punching the samples after solution heat treatment and less significant for punching after artificial ageing. The influence of sample preparation can be avoided by punching the samples before solution heat treatment. If this is not practicable, milling of the samples is a good alternative. The choice of quenching medium and short storage at room temperature before measurement (5 min) had only small effects on the DSC curves. Moreover, the start temperature of the measurement was found to be crucial. For observing phases forming below 100 °C and for low-bias baseline correction, the measurement should start at low-temperatures (i.e. ∼ − 50 °C). [ABSTRACT FROM AUTHOR]

Biodegradable chitosan-based films containing different concentrations of jatobá fruit peel extract (0.0%, 0.04%, 0.07%, 0.1% and 0.3%) were prepared and evaluated for their antioxidant and antimicrobial activities, physicochemical, morphological and thermal properties. The extract from jatoba fruit peel was obtained and incorporated into formulations of chitosan films. The films were characterized for thickness, moisture, solubility, water vapor permeability, optical properties, color and morphology. Also, thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy, in vitro antioxidant activity and antimicrobial activity were performed. The addition of extract at increasing concentrations increased the in vitro antioxidant activity by about 9–60 times compared with the film without extract. Films with lower extract concentrations were more effective at inhibiting nine bacterial strains, with emphasis on Escherichia coli (95.0% inhibition), Bacillus cereus (92.5% inhibition), Bacillus subtilis (96.5% inhibition), Pseudomonas aeruginosa (94.4% inhibition), Salmonella Typhimurium (90.4% inhibition) and Salmonella Enteritidis (93.9% inhibition). Addition of the extract improved the physical properties of the film, such as moisture, solubility, WVP and luminosity. The thermal stability of the films was slightly reduced with addition of extract at increasing concentrations. Films incorporating jatobá fruit peel extract showed potential utility as 'green' bioactive, biodegradable packaging, an alternative to packaging containing petroleum derivatives. [ABSTRACT FROM AUTHOR]

We investigated the inhibition of thermal runaway of styrene polymerization by DNPB. DNBP is an inhibitor in styrene polymerization reaction. Polymerization is one of eighteen hazardous processes. Styrene polymerization reaction is characterized by high heat production and fast reaction rate. Firstly, differential scanning calorimetry (DSC) and adiabatic calorimetry (ARC) were chosen to study the effect of different mass of DNBP on thermal behavior in non-isothermal and adiabatic environments. Secondly, exploring the inhibitory effect of DNBP at different runaway temperatures using an oil bath reactor. The results showed that when DNBP was at 0.80%, effective inhibition was obtained at different runaway temperatures. Finally, GC/MS and Gauss16 were used to infer the mechanism of inhibition in terms of macroscopic products and microscopic instabilities. The results showed that the products of the oil bath reactor experiments were related to the mass of DNBP, and when DNBP was 0.80%, the products increased and the main reaction was inhibited. Finally, it was deduced that the nitro group undergoes a possible path of direct addition reaction with the styrene radical before bond breaking. [ABSTRACT FROM AUTHOR]

Wood is a primary building tool for ancient buildings and structures, but for those that survive to date, naturally aged wood may pose a noteworthy fire hazard. There are potential risks to health, safety, and substantial cultural loss if fire risks in such buildings are not mitigated. We obtained several samples of aged wood commonly used in ancient structures (elm, pine, and aspen), and compared the kinetic and thermal characteristics to fresh wood examples to determine potential methods of enhancing safety. Differential scanning calorimetry was used to establish the heat release characteristics of the fresh and aged samples, and the characteristics of the thermal reaction stages were characterized using the temperature range and heat release laws for each reaction stage. The heat release characteristics during combustion were investigated for different heating rates, and the influence of aging on temperature change and heat release rate characteristics during different exothermic stages was assessed. Finally, using heat flow data, the apparent activation energy (AAE) of the samples and their distributions during different exothermic stages were calculated and analyzed via the Friedman differential iso-conversion method. Results showed that the exothermic energy of the aged samples was higher than that of the fresh samples, indicating that aging does impact the thermal reaction process. The aged samples in this study had a greater heat diffusion capacity, transmitted more heat, were more susceptible to burning (by spreading that heat), and generally posed a greater fire hazard. During the rapid exothermic phase, the AAE of aged wood increased as the reaction progressed, and exhibited lower AAE with a greater sensitivity to fire than fresh samples. A sound linear relationship between pre-exponential factor and AAE and the kinetic compensation effect was obvious. This study provided a rudimentary theoretical basis for the prevention of fires in timber-framed ancient buildings. [ABSTRACT FROM AUTHOR]

Overcoming limitations of poly (butylene succinate) (PBS) and enabling non-toxic, rapid production could lay the foundation for expanding applications in various fields. In this work, mechanically activated cassava starch (ACS) was used to augment the toughness of PBS and reduce the plasticization time of starch. The composite was prepared by melt blending PBS with two types of activated cassava starch particles (native starch and ACS) and acetyl tributyl citrate (ATBC) as a non-toxic plasticizer. X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FTIR), scanning electronic microscope (SEM), and differential scanning calorimetry (DSC) were used to investigate the structural changes, compatibility, and dispersibility of ACS particles in PBS. The results showed that under high-speed shear and grinding, the hydrogen bonds within ACS molecules were severely disrupted and the amorphous regions increased, leading to improved compatibility with PBS. Under the plasticization of ATBC, the cross-section of ACS composites was smoother. DSC results showed that addition of ACS significantly reduced crystallinity of PBS/ACS composites. Mechanical properties results showed that impact strength and elongation at break of PBS/ACS-12A were, respectively, increased by 125% and over 5 times compared with that of PBS. Water absorption test and contact angle test demonstrate a significant improvement in the water resistance of PBS/ACS. This study provides a simple and feasible method for preparing low-cost PBS biocomposites, and their extensions are expected to further replace general-purpose plastics in daily application. [ABSTRACT FROM AUTHOR]

Undoubtedly, with the increasing awareness of the scientific community and the public, current trends are directing research to implement effective and combined yet nature friendly methodologies. Due to advantages such as adaptability and versatility, the combination of electrospinning and light is increasingly intriguing. This study proposes a new strategy for producing amphiphilic fibers from graft copolymer of polypropylene (PP) and poly (acrylic acid) (FPP-g-PAA). The first step includes the synthesis of copolymer comprising PP main chain possessing poly (tertiary butyl acrylate) pendant groups via photo-induced metal-free atom transfer radical polymerization (PIMF-ATRP) of tertiary butyl acrylate (t-BA) in the presence of perylene and chlorinated polypropylene (PP-Cl) as a macro photo-initiator (PP-g-PtBA). Then, FPP-g-PAA is prepared by acidolysis of t-BA units to acrylic acid moieties. In the second step, the PP-g-PAA is successful electrospun to fabricate the ultimate amphiphilic fibers. The chemical steps are monitored and confirmed by Fourier-transform infrared (FT-IR) and proton magnetic resonance (1H-NMR) spectroscopies, and gel permeation chromatography (GPC). Following the structural characterization, morphological and wetting properties are systematically determined with scanning electron microscopy (SEM) and water contact angle (WCA) measurement by depending on surface characteristics of the samples. Thermal behaviour of precursors and synthesized electrospun fibers has also been evaluated and compared by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The SEM images display that the achieved fibers were smooth and circular with the average diameters ranging from 3.3 μm up to 3.9 μm. After WCA measurements, it was elucidated that the hydrophobic nature of electrospun PP-g-PtBA was transformed into amphiphilic structure by hydrolysis of PtBA pendant groups. The reported approach is very encouraging and expected to trigger further development for scientists preparing various types of amphiphilic polyolefin fiber based materials. [ABSTRACT FROM AUTHOR]

In this work, effect of varying lithium perchlorate (LiClO4) salt concentration in polymer gel electrolytes (PGE) containing heat resistant polymethyl methacrylate (PMMA), and succinonitrile (SN) is investigated via electrochemical and physical properties. The electrolyte specimen with high LiClO4 salt concentration of 1.5 M supports maximum ionic conductivity of 4.9 × 10–5 S cm−1 and electrochemical stability window of ~ 4 V. The ion-transport parameters evaluated from the tangent loss studies confirms that the optimized electrolyte possesses diffusivity (D) of 4.52 × 10–2, mobility (μ) of 1.746 cm2 V−1 s−1, number of charge carriers (N) of 1.78 × 1014 cm−3 and Nµ of 3.106 × 1014 cm−1 V−1 s−1. The dielectric constant studies show that the optimized electrolyte possesses maximum dielectric constant and lower value of modulus towards the high frequency region. The thermogravimetric and differential scanning calorimetry studies confirms that the prepared electrolytes offer weight loss of < 9% up to 373 K and maintains the gel phase up to 570 K, respectively. X-ray diffraction suggest that the PGE system becomes more amorphous with progressive addition of LiClO4 up to 1.5 M, while the Fourier transform Infra-red (FTIR) spectroscopy study reveal the salt-polymer interactions. [ABSTRACT FROM AUTHOR]

The main theme of the paper was focussed on the preparation, structural, optical, and photoluminescence studuies of p(-n-decyloxy) benzoic acid (10OBA) liquid crystalline (LC) compounds with 1 wt.% dispersed ZnO nanoparticles (NPs). The prepared samples were subsequently characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), optical polarizing microscopy (POM), differential scanning calorimetry (DSC), UV-Visible spectroscopy, and photoluminescence (PL) studies. From the XRD, the diffraction peaks observed at 36.2, 42.5, 61.3, and 73.2° were well resolved, indicating the presence of ZnO NPs and the particle size was found to be 65 nm. SEM studies revealed the uniform dispersion and the presence of ZnO NPs in the samples. The textural images of different phases (nematic, smectic) of liquid crystalline compounds of 10OBA pure and 10OBA with 1 wt.% dispersed ZnO NPs were observed through the POM with reduced temperature. From the DSC thermograms, the phase transition temperatures and the correponding enthalpy values were estimated. The bandgap reduces for 10OBA LC compound with the dispersion of 1 wt.% ZnO NPS and it is estimated as 3.25 eV compared with 4.25 eV for the undoped 10OBA LC compound. PL studies showed the presence of the peak at 616 nm owing to the presence of point defects within the bandgap-like vacancies and interstitials known as deep-level emission. [ABSTRACT FROM AUTHOR]

It is common knowledge that in-situ combustion is highly promising method for improving heavy oil recovery. The present research explores the effects of Cobalt-ligated catalysts derived from sunflower oil (CoSFO) and tall oil (CoTO) on heavy oil oxidation, aiming to enhance in-situ combustion process. Through differential scanning calorimetry (DSC) we assessed the oxidation kinetics of heavy oil in the presence and absence of these catalysts. Our findings indicate that both CoSFO and CoTO significantly improve the oxidation process, particularly in the high-temperature oxidation (HTO) phase crucial for combustion front stabilization. Notably, CoTO demonstrated superior efficacy in reducing oxidation times across all conversion levels, suggesting its potential to optimize the efficiency of EOR techniques. This research highlights the promise of Cobalt-ligated catalysts in advancing heavy oil recovery and suggests directions for future studies to further investigate their industrial applications. [ABSTRACT FROM AUTHOR]

A familiar polyalcohol, 1,2-propanediol (12PDO), is among the simple alcoholic solvents with high solubility for lithium tetrafluoroborate (LiBF4), as well as a wide temperature range for liquids. The viscosity of 12PDO solutions containing LiBF4 was measured in the temperature range of 280‒340 K using a vibrational viscometer, and it exhibited non-Arrhenius behavior fitted with the Vogel–Fulcher–Tamman (VFT) equation, which is an empirical model for describing liquid dynamics. The viscosity (η) increased with the increasing mole fraction of LiBF4 (x), and the variation in η was found to be mainly controlled by the pre-exponential factor η0 in the VFT expression. The VFT-fitting parameters, the strength parameter (D), and ideal glass transition temperature (T0), which indicate the Arrhenius behavior and an ideal glass transition temperature, respectively, correlated with the thermal analysis results that were obtained via differential scanning calorimetry. With the increasing x, the value of D decreased rapidly for x < 0.20, whereas it remained approximately unchanged for x > 0.20. The concentration dependence of T0 also differed at approximately x = 0.20. The changes in D and T0 with x indicated that the intrinsic hydrogen-bonding networks between the solvent molecules were rapidly destroyed by the added ions at reduced salt concentrations, while such a structural breaking effect of the added ions weakened owing to ion associations at increased salt concentrations. Thus, it was observed that the solvation structure and dynamics of the solutions strongly depended on the salt concentration. [ABSTRACT FROM AUTHOR]

Pectin gel and retinyl palmitate (RP)-loaded monoolein (MO) cubic phases were prepared by a melt-hydration method as a salt-responsive and anti-oxidative vehicle. The pectin gel was formed maximally when CaCl2 concentration in aqueous pectin solution (0.25% to 2%) was 50 mM. The phase transition temperature (PTT) of the cubic phase, determined by differential scanning calorimetry (DSC), decreased from 58 to 46.9 ℃ as the RP content increased from 0 to 1.5%. The maximum release degree at 22 ℃ of a dye (amaranth) loaded in a cubic phase was about 15.9% and 51.3%, respectively, when the release medium was deionized water and PBS (10 mM, pH 7.4). An ion exchange between Na+ and Ca2+ seemed to cause the extensive release in the saline. The in vitro radical scavenging capability (RSC) of RP loaded in the cubic phase was proportional to the RP concentration and the RSC was substantially higher than that of free RP. The double bond of MO contained in the cubic phases was chemically stable during 6 months storage at 25 ℃ and 40 ℃, evidenced by 1H NMR spectroscopy. The cubic phases maintained their integrity and retained their unique structure (the water channels winded by the lipid layers) under the same storage conditions. [ABSTRACT FROM AUTHOR]

2,6-Di-tert-butyl-4-methylphenol (BHT) is an excellent antioxidant that is easily oxidized to 2,6-di-tert-butyl-4-hydroperoxyl-4-methyl-2,5-cyclohexadienone (BHTOOH). For the safety of BHT production and usage, it is meaningful to study the thermal stability and decomposition properties of BHT and BHTOOH. In this paper, the thermal decomposition properties of BHT and BHTOOH were compared by the mini closed pressure vessel test (MCPVT) and differential scanning calorimetry (DSC). Their kinetics of thermal decomposition were studied using thermogravimetric analysis (TGA). The thermal decomposition products of BHT and BHTOOH were analyzed by gas chromatography-mass spectrometry (GC–MS). The results show that there was no significant change in temperature pressure when BHT was warmed up under a nitrogen atmosphere, indicating that BHT was stable within 400 K. The thermal decomposition reaction of BHTOOH was rapid with an initial reaction temperature of 375.2 K. The initial exothermic temperature (Ti) and heat release (QDSC) of DSC were 384.9 K and 865.0 J g−1, respectively. The apparent activation energies (Ea) for the thermal decomposition reactions of BHT and BHTOOH calculated by the Kissinger method were 151.8 kJ mol−1 and 66.07 kJ mol−1, respectively. The main decomposition products of BHT were isobutene and 2-tert-butyl-4-methylphenol. The thermal decomposition products of BHTOOH included BHT, 2,6-di-tert-butyl-4-ethylphenol, 3,5-di-tert-butyl-4-hydroxybenzaldehyde, 4,4′-(1,2-ethanediyl) bis [2,6-bis (1,1-dimethylethyl) phenol, etc. Based on the thermal decomposition behavior and products, the reaction pathway has been described. These results indicate that BHT is a potential thermal hazard during production, storage and application. For the safety of the chemical industry, the oxidation of BHT should be avoided. [ABSTRACT FROM AUTHOR]

Bio-based coating materials have received increased attention because of their low-cost, environmentally friendly, and sustainable properties. In this paper, a novel coating material was developed to coat ureas using bio-based coating material derived from liquefied eggplant branches to form controlled-release ureas (CRUs). Also, the optimum proportion of liquefier was studied. Furthermore, dimethyl siloxane was used to modify liquified eggplant branches to make them hydrophobic, resulting in hydrophobic controlled-release ureas (SCRUs). This hydrophobic-enabled coating is environmentally friendly and highly efficient. The products were characterized by specific scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry, and the water contact angles of CRUs and SCRUs were determined. The nutrient-release characteristics of the SCRUs in water were determined at 25 °C and compared with those of CRUs. The results showed that the modification with dimethyl siloxane reduced the N release rate and increased the longevity of the fertilizer coated with hydrophobic bio-based coating material. In addition, organosilicon atoms on the SCRU surface also block the micro-holes on the coating and thus reduce the entry of water onto the coating. The results suggest that the new coating technology can create a hydrophobic surface on bio-based coating material and thus improve their controlled-release characteristics. [ABSTRACT FROM AUTHOR]

We conducted a comprehensive investigation to understand the effects of sequential aging temperature profiles on Neoprene rubber, aiming to provide a clearer understanding of the purpose, methodology, findings, and implications of our work. Two sequential thermal aging conditions were applied to the Neoprene rubber samples in a controlled, moisture-free environment. The characterization of the aged samples included crosslinking density analysis using swelling tests, Differential Scanning Calorimetry (DSC), and uni-axial tensile tests. Our study focused on unraveling the changes in the physical and mechanical properties of the Neoprene matrix resulting from thermal aging. Notably, we found that the degradation of Neoprene was influenced by both the temperature and the order of the aging profiles. Higher temperatures led to increased cross-linking density and improved thermal stability, indicating a prevalence of oxidation cross-linking over chain scission. This led to the creation of a more compact network structure within the material. Moreover, we introduced the concept of damage capacity, which revealed that different mechanisms of damage affect the material's toughness with varying degrees of impact. This understanding emphasizes the limited capacity for damage and subsequent mechanisms' reliance on the remaining capacity. The significance of our work lies in shedding light on the interplay between thermal aging conditions and the behavior of Neoprene rubber. The findings provide valuable insights for material design and have implications for a range of applications. [ABSTRACT FROM AUTHOR]

The present study displays a comprehensive investigation into the micro- and macrostructures of gluten and its responses to temperature-induced changes, employing various analytical techniques. The integration of time domain-nuclear magnetic resonance (TD-NMR), differential scanning calorimetry (DSC), size-exclusion high-performance liquid chromatography (SE-HPLC), field emission scanning electron microscopy (FESEM), solid-state nuclear magnetic resonance (ssNMR), and multiphoton laser microscopy (MLM) measurements facilitates the multidimensional examination of gluten's phase distribution and structure across various scales. Notably, TD-NMR helps to refine prior T2 assignments for hydrated gluten through dynamic T2 measurements at sub-zero temperatures. The innovative application of TD-NMR uncovers insights into freezable water quantities and their changes under varying temperature conditions. Through real-time analyses utilizing not only TD-NMR but also MLM techniques, along with SE-HPLC measurements, the study highlights increased lacunarities in the gluten structure, particularly between 60 and 85 °C. These structural changes are attributed to heating effects that unfold and denature proteins and culminate in aggregation and crosslinking phenomena, leading to the release of water into macropores, hence changes in the water distribution in the gluten matrix. [ABSTRACT FROM AUTHOR]

A new energetic co-crystal of trinitrotoluene (TNT) and pyrene (PYRN) with a 1:1 molar ratio was prepared by a slow solvent evaporation technique. Co-crystal physicochemical properties have also been examined using optical microscopy, powder X-ray diffraction, single crystal X-ray diffraction, and differential scanning calorimetry. The results of single-crystal X-ray diffraction and non-covalent interaction calculations showed that non-covalent interactions (donor–acceptor π-π interaction) govern the structures of the TNT:PYRN co-crystal. The experimental and theoretical outcomes supported each other in the study. Thermal stability, impact sensitivity, and detonation performance of the co-crystal were investigated. DSC measurement indicates that the co-crystal has a melting point of 167 °C and a decomposition temperature of 293 °C, indicating outstanding thermal stability. The co-crystal was found to be less impact-sensitive than TNT using the BAM fall hammer instrument. Furthermore, the calculated detonation velocity and detonation pressure of the co-crystal are 5.29 km·s−1 and 8.48 G Pa, respectively. As an outcome, the TNT:PYRN co-crystal may be a promising intermediate energy explosive with low sensitivity and, as such, may be a desirable explosive alternative in the future instead of TNT for low-vulnerability formulations. [ABSTRACT FROM AUTHOR]

Solvent evaporation was used to create a novel organic Schiff-based optical crystal of Benzimidazolium gallate (BGA). The size of unit cells was determined using X-ray diffraction analysis. Fourier transform infra-red spectrum analysis revealed chemical bonds' vibrational behavior and their functional groups' existence. Optical transparency and optical bandgap (3.66 eV) were observed by the UV–visible-near infrared spectral analysis. Differential scanning calorimetry curves show that decomposition is exhibited at 215 °C. Dielectric experiments on the BGA crystal were performed at ambient temperature. High-resolution scanning electron microscope analysis shows the crystal's nature and surface shape. The Z-scan process explored the BGA crystal's nonlinearity, and the crystal is suitable for photonic, optoelectronic, and optical-limiting applications. [ABSTRACT FROM AUTHOR]

Poly(propylene 2,5-furandicarboxylate) is a kind of bio-based polyester, but the raw material (2,5-furandicarboxylic acid) is expensive. The purpose of this study is to investigate the effect of cheap 2,5-thiophenedicarboxylic acid on the synthesis and properties of poly(propylene 2,5-furandicarboxylate). 2,5-Furandicarboxylic acid, 2,5-thiophenedicarboxylic acid, and 1,3-propanediol were used to synthesize poly(propylene 2,5-furandicarboxylate), poly(propylene 2,5-thiophenedicarboxylate), and poly(propylene 2,5-furandicarboxylate-co-propylene 2,5-thiophenedicarboxylate). The thermal properties, dynamic mechanical properties, and rheological properties were characterized. The structures and properties of the copolymers were compared with those of two homopolymers. Fourier transform infrared spectroscopy and nuclear magnetic resonance spectra suggested that the copolymers were successfully synthesized. Differential scanning calorimetry and wide-angle X-ray diffraction results showed that poly(propylene 2,5-thiophenedicarboxylate) exhibited better crystallization ability. Compared with poly(propylene 2,5-furandicarboxylate), poly(propylene 2,5-thiophenedicarboxylate) is more prone to βrelaxation due to the larger angle between the two carbonyl groups connected to the thiophene ring and sulfur atom with weaker electronegativity. [ABSTRACT FROM AUTHOR]

For the first time, a bimetallic metal–organic framework of (MOF) La3+ and Ce3+ (Ce, La-MOF) was synthesized using a new solvothermal route. Also, monometallic MOFs La3+ (La-MOF) and Ce3+ (Ce-MOF) were synthesized using the mentioned method. To identify, and analyze the synthesized nanostructures, field emission scanning microscopy (FSEM), energy dispersive X-ray mapping (MAP), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermal gravity curve (TGA), differential scanning calorimetry (DSC) analysis, Fourier transforms infrared (FT-IR) spectroscopy and Brunauer–Emmt–Teller surface area (BET) were used. According to the XRD diffraction patterns of Ce–La-MOF nanostructure, no additional peaks are derived from La species, which confirms that the addition of La does not change the crystalline phase structure of Ce-MOF. The size of La-MOF, Ce-MOF, and Ce, La-MOF nanostructures was calculated by the Williamson-Hall method and reported as 72.97, 55.46, and 81.55 nm, respectively. The specific surface area (BET) results for La-MOF, Ce-MOF, and Ce, La-MOF nanostructures were reported as 140, 200, and 260 m2 g−1 respectively, and the mean pore volumes of the nanostructures were reported as 0.019, 0.022 and 0.030 cm3 respectively. These values allow the use of these versatile nanostructures in various applications such as biosensing, separation and purification, medicine field, and catalysts. In addition, in this study, modified electrodes for synthesized nanostructures were tested for the electrooxidation of acetaminophen. And the obtained results show better electrocatalytic behavior of bimetallic Ce, La-MOF nanostructures than monometallic La-MOF, Ce-MOF nanostructures against acetaminophen. [ABSTRACT FROM AUTHOR]

Basalt fiber is prone to slip and fall off in asphalt system. To improve the interfacial adhesion strength between basalt fibers (BFs) and asphalt, titanate coupling agents (TCAs) were applied to BF-reinforced asphalt. The mechanical properties of fibers with TCA concentration (6%, 8%, 10%, 12%) and infiltration time (10 min, 30 min, 60 min, 90 min) were tested by monofilament tensile strength test to obtain the best treatment conditions. The crystal phase, functional group, microstructure, and elemental changes of the TCA-treated basalt fibers were characterized by X-ray diffractometer, Fourier infrared spectroscopy (FT-IR), and X-ray energy-dispersive spectroscopy. The controlled group (untreated basalt fibers) was also prepared for comparison. Meanwhile, the adhesion work and interfacial bonding strength between asphalt and basalt fibers were compared and quantitatively assessed through pull-out tests. Additionally, the thermal stability of asphalt was evaluated using the differential scanning calorimetry test, while the surface morphology of the fractured asphalt sections was observed through scanning electron microscopy. The results show that the surface of basalt fibers was chemically modified by TCA successfully, forming octopus-inspired micro-sucker coated. Through this process, the nascent Si–O–Ti bond acts as a tie connecting the basalt and asphalt surface, which promoted the adhesive properties of BF to asphalt. Compared with the control group, the adhesion work and adhesion energy of basalt fibers-asphalt increased by 20.05% and 26.82%, respectively, and the thermal stability was improved. The experimental results show that after the treatment of the fiber surface by TCA, the interaction between the fiber and the asphalt is strengthened, and the interfacial bonding morphology is improved. [ABSTRACT FROM AUTHOR]

The ammonium perchlorate (AP) plays a key role in the production of highly energetic materials for application in aerospace propulsion; and the development of catalysts for the production of high burning rate (BR) propellants based on AP is an active field of research. Recently, the graphitic carbon nitrides have been used as a metal-free catalyst for the AP thermal decomposition. Following this line of C=N conjugated polymeric systems used as modifiers, herein, the thermal behavior and decomposition mechanism of AP in the presence of hydrogen cyanide (HCN)-based polymers are described. These novel functional materials can be synthesized from the HCN tetramer, diaminomaleonitrile (DAMN) by a very simple one-pot thermal bulk polymerization. In the present work, the morphological characterization of these DAMN polymeric products and their effect in the thermal decomposition of AP was performed by differential scanning calorimetry (DSC). They were shown to exhibit catalytic activity for the thermal decomposition of this relevant oxidizer. Thus, adding 10% by mass of these nitrogen-containing conjugated polymers to AP decreases both the maximum exothermic peak temperature of decomposition and activation energy (Ea). In addition, thermogravimetry–mass spectrometry (TG–MS) analysis has allowed to evaluate the effect of these innovative activators on the AP thermal decomposition mechanism. Evolved gas analysis seems to indicate that nitrogenous species, such as N2 and N2O, are increased in the presence of these two-dimensional (2-D) macromolecular combustion additives. As a result, the DAMN polymers show a notable potential as a new kind of activators for the development of more efficient AP-based composite propellants. [ABSTRACT FROM AUTHOR]

The thermal properties of a series of substituted alkoxyaryls 1–5 and N-(n-butyloxybenzylidene)-p-propiophenone (6) were studied by differential scanning calorimetry. The phase transition temperatures and heats were determined. Compounds 1–5 do not form a mesophase during the melting process, unlike compound 6, which sbows several liquid-crystalline transitions. To explain the thermal properties, crystals of compound 4, containing sulfonyl fluoride and amino groups, and compound 6 were studied by X-ray diffraction at different temperatures. The crystal packing of 4 consists of dimers connected by weak hydrogen bonds and is composed of alternating aliphatic and aromatic regions. The absence of mesomorphism in compounds 1–5 can be attributed to the dominant role of a long (C14—C18) alkyl substituent in the formation of the packing. In the crystal packing of 6, there are clearly distinguished loose aliphatic and dense aromatic regions. Along with the stabilizing C—H⋯π and C—O⋯H interactions, this packing allows the existence of several liquid-crystalline phases on heating. [ABSTRACT FROM AUTHOR]

Polystyrene waste was converted into an ecofriendly adhesive using a toluene–acetone solvent system and compared to that of toluene solvent. The bond strengths of the adhesives were determined. The adhesive with the maximum bond strength was tested for pH, water content, flow behavior, the effect of temperature on viscosity, thermogravimetric analysis, and differential scanning calorimetry. The influence of viscosity on the adhesive bond strength was checked. Fourier transform infrared spectroscopy was used to identify the functional groups in the adhesive, and the effect of toluene and acetone solvent mixing on the bond strength of the polystyrene waste adhesive (PSWA) was determined. An increase in polystyrene concentration increased the adhesive viscosity. Temperature changes did not influence the adhesive's pseudo-plasticity but influenced its viscosity, as temperature rise resulted in a viscosity decrease. The toluene–acetone PSWA sample with a viscosity of 615.01 cP provided the best bond strength and a further decrease or increase in viscosity reduced the bond strength. The bond strength of the toluene–acetone adhesive system was significantly lower than that of the toluene system. The toluene–acetone system, on the other hand, is more environmentally friendly than that of toluene, and its maximum bond strength value of 0.637 N/mm2 is within the range of bond strength values for particleboard production. The eco-friendlier adhesive has a pH of 5.76 and a water content of 5.82% which are also within the range for particleboard adhesives. The eco-friendlier PSWA is more thermally stable with a slower thermal decomposition rate than that of the toluene (control) sample. Its pseudoplastic flow behavior is advantageous for adhesive applications. [ABSTRACT FROM AUTHOR]

This study aimed towards the fabrication of biodegradable packaging films using carboxymethyl guar gum (CMG) as the base material. Various ratios of glycerol (Gly) as a plasticizer and glutaraldehyde (Glu) as a cross-linker were employed in the synthesis of these biopolymer-based films through the solution casting technique. Comprehensive characterization, such as attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), was conducted. The films were further examined for tensile strength, percent elongation, thickness, solubility in water, gloss, haze, and transparency. The maximum tensile strength of 37.82 MPa, maximum percent elongation of 124.20%, maximum gloss of 25.52% at a 20° angle, maximum haze of 41.93%, maximum transparency of 88.53%, and a minimum water solubility of 60.42% were observed for the developed films. This reveals that CMG-based films hold promising potential as a novel biomaterial for future applications in packaging, such as edible coatings and water-soluble, biodegradable packaging films. [ABSTRACT FROM AUTHOR]

Non-isocyanate polyurethane (NIPU) is one of the hot spots in the scientific research of polyurethane. In this work, mechanically regulable NIPU were prepared by ring-opening polymerization of cyclic carbonates via diamines. Cyclocarbonates with different functionalities were firstly synthesized by thiol-ene click reaction, which was characterized through nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy. The controllable mechanical performance of NIPU films was obtained by the structure of the diamines and the functionality of the thiol groups. The results of swelling and differential scanning calorimetry experiments suggested that the control of functionality and reactivity endowed the material with an adjustable crosslinking density. The Young's modulus of the material could be regulated from 51.3 to 765.1 MPa. Furthermore, the studied films also showed good thermal stability. The present study provides some guidance for the preparation of non-isocyanate polyurethane coatings for different application scenarios. [ABSTRACT FROM AUTHOR]

Background: Niosomes hold promise as drug delivery systems for cancer treatment, with niosome size impacting stability, biodistribution, and effectiveness. This study optimized methotrexate (MTX)-loaded niosome formulation by studying the effects of components and processing conditions on size. The niosomes formulation was made by the thin-film hydration technique. Results: The optimized formulation (NIO 17) with a 6:2:2 ratio of span 60, soya PC, and cholesterol achieved 55.05% methotrexate encapsulation, particle size 597.2 nm, PDI 0.49, and zeta potential − 23.3 mV. The compatibility of methotrexate with lipids was confirmed via Fourier transform infrared spectroscopy, and transmission electron microscopy revealed spherical, well-dispersed vesicles. Differential scanning calorimetry indicated methotrexate conversion or entrapment within vesicles. In vitro release exhibited a sustained pattern with an initial burst. NIO 17 showed potent anti-cancer activity against B16-F10 cells (GI50: 38.7176 μg/mL). Ex vivo studies suggest tailoring niosome size (597.2–982.3 nm) to target specific skin depths (0–38 μm) for enhanced localized drug delivery. Conclusions: This study demonstrates the potential of methotrexate-loaded niosomes as a novel cancer therapy approach, highlighting the potent anti-cancer activity and transdermal delivery potential of NIO 17. Further research is necessary to explore its clinical translation. [ABSTRACT FROM AUTHOR]

Due to their outstanding chemical and physical properties, polyimides are widely used in industrial applications. The degree of imidization of polyimides significantly influences their properties, making it an important factor in tailoring the material for specific applications. Imidization refers to the process of converting a precursor poly(amic acid) by removing water, and it is essential to analyze this process in detail to tune the final structure and properties of the material. Conventional techniques for this task include Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), or differential scanning calorimetry (DSC), but they lack the possibility of spatially and/or depth-resolved analysis or do not enable in-line monitoring capabilities. To overcome these limitations, we propose laser-induced breakdown spectroscopy (LIBS) as a powerful tool for the monitoring of the imidization reaction. To establish a measurement method, a total of 130 in-house prepared, self-synthesized samples were thermally cured to exhibit varying imidization degrees. IR spectroscopy served as a reference technique during method development, and a novel formula for calculating the degree of imidization, based on the C2 and H signal trends, was introduced. The calculated imidization degrees of model thin films based on LIBS were in good accordance with the IR reference method although minor differences between the two methods were expected due to varying information depth and the size of the sampled area. Additionally, the robustness of the procedure was demonstrated by depth profiling of a stacked model polymer, spiking with commercially available additives and, ultimately, by analyzing industry-relevant polymer samples. [ABSTRACT FROM AUTHOR]

The production of modern composite materials based on bulk metallic glasses requires knowledge of their primary crystallization processes during heating (BMG). Here, we investigate the structure and crystallization kinetics of a promising modern BMG/B2 nano-composites, a fast-hardened glass-forming alloy Cu50Zr42.5Ti7.5. The complex four-step crystallization of the glass alloy at different heating rates was revealed by differential scanning calorimetry. The process of a crystallization was successfully fully described by a multiverse nonlinear kinetic model, and the kinetic parameters were determined with high accuracy. The best way to describe the four-step crystallization of a glass alloy is the two-branch parallel reaction. The first branch is described by three consecutive n-order autocatalytic reactions. The second branch obeys the Avrami-Erofeev model. The high thermal stability of the amorphous state is evidenced by the average full process crystallization activation energy Ea = 425 kJ mol−1. Analysis of the obtained results and their comparison with available literature data allow us to conclude that the crystallization process in glassy Cu50Zr42.5Ti7.5 alloy (and probably other similar ternary alloys based on binary Cu50Zr50 system) is strongly affected by the structure of initial sample as well as by thermal conditions. The presence of nano-sized inclusion of metastable phases (for example, B2 one) can change the sequence of reaction as well as the structure of phases forming at each stage. [ABSTRACT FROM AUTHOR]

Three 4-(1H-tetrazole-5-yl-amino)-1,2,4,5-tetrazine-1-one (TATzO) metal salts, K2(TATzO)(H2O) (1) and Mg(TATzO)(H2O)6·2H2O (2) and Sr(TATzO)(H2O)4 (3), were synthesized and characterized using Fourier transform infrared (FTIR), elemental analysis, single-crystal X-ray diffraction, and powder X-ray diffraction patterns. The crystal structure and hydrogen bonding interactions have been analyzed. It turns out that 1 and 3 crystallize into a three-dimensional topological network and have strong π–π stacking and hydrogen bonding interactions. Furthermore, the geometric optimization of 1–3 was performed using B3LYP-D3/def2svp in Gaussian 16 software package and then analyzed by reduced density gradient. The thermal behavior was conducted using differential scanning calorimetry and thermogravimetric (TG). The decomposition temperature of the three complexes exceeds 250 °C, much higher than that of TATzO (230 °C). The thermal decomposition products of 1 were further studied using thermogravimetric-Fourier transform infrared-mass spectrometry (TG/FTIR/MS). The impact sensitivity test indicated that making complexes can help decrease the sensitivity of the original energetic ligand. [ABSTRACT FROM AUTHOR]

This research article discusses composite panel manufacturers' challenges in finding an optimum pressing time to achieve a trade-off between the panel's performance and the production cost. Real-time cure monitoring techniques, such as dielectric analysis (DEA), have been developed to overcome the limitations of trial-and-error methods, which have been in use for a long time for the same purpose. DEA measures changes in the dielectric properties of the material during the cross-linking reactions in resin and provides necessary information for the cure state of the material. In this study, paper sensors based on interdigitated electrodes were employed to measure the curing behavior of phenol formaldehyde resin-impregnated paper. The paper sensors were found to be better than commercially available sensors in terms of compatibility, thinness, biodegradability, low cost, flexibility, and non-heterogeneity. The study compared the results obtained from DEA with those from differential scanning calorimetry (DSC) and found that DEA can be a good candidate for predicting curing behavior. The average enthalpy of the curing measured using DSC for the B-stage resin-impregnated PF resin was 35.28 J g−1. Moreover, it was observed from the rate of cure that at a higher temperature of 180 °C, the reaction follows an autocatalytic kinetic type as the reaction rate passes through a maximum. However, at lower temperatures, the autocatalytic reaction regime seems to be followed by a decelerating type. Further research on the effect of pressure and other parameters on the curing behavior of PF resin-impregnated paper can be done in the future. [ABSTRACT FROM AUTHOR]

Amorphous materials specifically chalcogenide glasses (Se, Te, and Sb alloys) are promising materials for fabrication of different solid-state devices and their characteristics can further be improved by doping with rare-earth element. Current study deals with phase transformation, thermal stability, and crystallization kinetics of Er-doped quaternary chalcogenide system which were synthesized using melt quenching technique. In this study, Ge17Sb8Se75−xErx (x = 0, 0.4, 0.8, and 1.0) alloy has been examined from differential scanning calorimetry data wherein the stability and kinetics is studied at variable heating rates. As a standard procedure, non-isothermal conditions were used throughout the kinetic and crystallization studies for understanding the variation in glass transition temperature, melting temperature, thermal stability factor, activation energy of glass transition, and crystallization wherein besides the role of chalcogen element, the doping concentration of rare-earth Er is also understood. Furthermore, devitrification resistance was also analyzed based on activation energy for crystallization. The synthesized Er-doped GeSbSe system shows an increase in transition temperature, melting temperature, thermal stability, and glass-forming ability when the concentration of Er and heating rate increases as compared to the pure alloy. Furthermore, decrease in the activation energy has been observed for Er-doped quaternary chalcogenide system. These observations indicate the potential of Er-GeSbSe chalcogenide glass as phase change memory material and other applications which needs high thermal stability. [ABSTRACT FROM AUTHOR]

The temperatures of the phase transitions for polyethyleneterephthalate samples containing recycled PET (the product Vivilen) and the waste materials from its production were analyzed by differential scanning calorimetry and x-ray structural analysis, and the ratio of the crystalline and amorphous phases was determined. The polyethyleneterephthalate samples were arranged according to their glass transition and melting points, which made it possible to correlate the samples according to the degree of crystallinity. In order to obtain a filament based on the dust waste from the solid-phase polycondensation process an extrusion temperature regime was established, and samples of filaments for 3D printing that meet the requirements of GOST R 59100-2020 were obtained. [ABSTRACT FROM AUTHOR]

In the world practice, the organic carbon content (Corg) in the soils containing carbonates is measured in different ways. We have analyzed the methods for solving this problem including the state-of-the-art approaches, such as thermogravimetry, differential scanning calorimetry, and spectroscopy. As is shown, the presence of CaCO3 does not prevent the Corg measurement with dichromatometric method (Tyurin and Walkley–Black variants). The disadvantages of this method comprise the laborious analysis, constant presence of operator, incomplete oxidation of organic compounds, and environmental pollution. The measurement of soil weight loss-on-ignition (LOI) is economical and rapid but overestimates Corg content because of inadequacy of the conversion factor of 1.724, the presence of adsorbed and chemically bound water, as well as mineral components decomposing at T = 105–550°C. The most relevant solution for assaying the Corg content in carbonate soils is to use an analyzer and a calcimeter although the accuracy of Corg measurements in the presence of carbonates is significantly reduced because the errors of two methods are quadratically summed. A high cost of the device, maintenance, verification, and repair limit its widespread use in soil laboratories. The content of soil carbonates can be measured using both gravimetric (LOI) and volumetric (calcimeter) methods. The latter method is preferable for the soils with the prevalence of CaCO3 in carbonates. The preliminary removal of carbonates from soil samples is labor-intensive and can cause a partial loss of Corg via acid extraction. A high cost of the instruments and the absence of the libraries of soil spectra hinder the development of Vis-NIR and MIR spectroscopy as an alternative to wet chemistry methods. Further comparative studies will give a deeper insight into the spatial patterns in the distribution of soil organic carbon. [ABSTRACT FROM AUTHOR]

The objective of this research was to develop active packaging that used a vapor-phase antimicrobial agent incorporated into chitosan capsules to extend the shelf life of dry cakes. The clove essential oil (CEO) was encapsulated into chitosan capsules using an emulsion-ionic gelation crosslinking technique. CEO loading in chitosan was taken in different ratios (0.0:1, 0.25:1, 0.50:1, 0.75:1, 1:1, 1.25:1, 1.50:1) and validated using Fourier Transform-Infrared (FT-IR) spectra and a Field-Emission Scanning Electron Microscope (FE-SEM). The thermal stability of the capsules was evaluated using thermogravimetric analysis (TGA). Differential Scanning Calorimetry (DSC) was used to assess the oxidative thermal stability of the compounds. The encapsulation efficiency and loading capacity were 12.01 and 8.01 for 1.50:1 (CEO: Chitosan) loaded samples. The antimicrobial activity of active capsules was performed in the vapor phase. It completely prevented the development of E. coli and S. aureus when CEO was used with chitosan in more than a 1:1 ratio. Finally, the dry cakes were packed with active capsules, and bacterial growth was reduced until the 10th day of packing. [ABSTRACT FROM AUTHOR]