Thermal Stability Analysis of Lithium-Ion Battery Electrolytes Based on Lithium Bis(trifluoromethanesulfonyl)imide-Lithium Difluoro(oxalato)Borate Dual-Salt

Lithium-ion batteries with conventional LiPF6 carbonate electrolytes are prone to failure at high temperature. In this work, the thermal stability of a dual-salt electrolyte of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium difluoro(oxalato)borate (LiODFB) in carbonate solvents was analyzed by accelerated rate calorimetry (ARC) and differential scanning calorimetry (DSC). LiTFSI-LiODFB dual-salt carbonate electrolyte decomposed when the temperature exceeded 138.5 °C in the DSC test and decomposed at 271.0 °C in the ARC test. The former is the onset decomposition temperature of the solvents in the electrolyte, and the latter is the LiTFSI-LiODFB dual salts. Flynn-Wall-Ozawa, Starink, and autocatalytic models were applied to determine pyrolysis kinetic parameters. The average apparent activation energy of the dual-salt electrolyte was 53.25 kJ/mol. According to the various model fitting, the thermal decomposition process of the dual-salt electrolyte followed the autocatalytic model. The results showed that the LiTFSI-LiODFB dual-salt electrolyte is significantly better than the LiPF6 electrolyte in terms of thermal stability.

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Application of ionic liquid [bmim]PF6 as green plasticizer for poly(L-lactide)

e-Polymers ◽

10.1515/epoly.2008.8.1.1970 ◽

2008 ◽

Vol 8 (1) ◽

Author(s):

Puyu Zhang ◽

Lichao Peng ◽

Wenbin Li

Keyword(s):

Thermal Stability ◽

Differential Scanning Calorimetry ◽

Ionic Liquid ◽

Glass Transition ◽

Transition Temperature ◽

Poly Ethylene Glycol ◽

Scanning Calorimetry ◽

Poly Ethylene ◽

Thermal Stability Of ◽

Better Than

AbstractIonic liquid [bmim]PF6 (1-butyl-3-methylimidazolium hexafluoro phosphate) was synthesized and characterized. It was used as the plasticizer for poly(L-lactide) (PLLA). The glass transition temperature (Tg) and the thermal stability of the plasticized PLLA samples were measured by thermogravimetry (TG) and differential scanning calorimetry (DSC). Compared with poly(ethylene glycol) having Mw of 300 g/mol (PEG300), TG results showed that the thermal stability of PLLA plasticized with ionic liquid was better than that of PLLA plasticized with PEG300. The Tg of plasticized PLLA decrease with increasing the content of ionic liquid [bmim]PF6 from 2 wt.% to 10 wt.%. The Tg of PLLA can be reduced to 40°C when the content of ionic liquid [bmim]PF6 was 10 wt.%. The materials of PLLA with plasticizer were also investigated using polarizing microscope (POM), the results of which indicate that the movements of PLLA chains were improved when ionic liquid plasticizer was used.

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Synthesis of Flame-retardant Phosphaphenanthrene Derivatives with High Phosphorus Contents

Australian Journal of Chemistry ◽

10.1071/ch13722 ◽

2014 ◽

Vol 67 (11) ◽

pp. 1688 ◽

Cited By ~ 1

Author(s):

Jinyun Zheng ◽

Yujian Yu ◽

Lulu Zhang ◽

Xiaomin Zhen ◽

Yufen Zhao

Keyword(s):

Thermal Stability ◽

Flame Retardant ◽

High Resolution Mass Spectrometry ◽

Lithium Ion ◽

Decomposition Temperature ◽

Gravimetric Analysis ◽

Scanning Calorimetry ◽

High Phosphorus ◽

Phosphorylation Reaction ◽

Flame Retardant Properties

Two novel types of phosphate derivatives of phosphaphenanthrene with a high phosphorus content were prepared by phosphorylation reaction between either 2-(6-oxido-6H-dibenz<c,e><1,2>oxaphosphorin-6-yl)-methanol (ODOPM) or 2-(6-oxido-6H-dibenz<c,e><1,2>oxaphosphorin-6-yl)-1,4-benzenediol (ODOPB) and dialkyl phosphoryl chloride. The structures of all compounds were characterised by 1H NMR, 13C NMR, 31P NMR, Fourier transform infrared spectroscopy, and high-resolution mass spectrometry. The thermal stability of representative compounds was determined by thermal gravimetric analysis and differential scanning calorimetry. The results showed that the compounds have excellent resistance to oxidation, high thermal stability with an onset decomposition temperature above 200°C, and a high char yield over 25 %, owing to the high P content. The representative compound was added to conventional electrolytes of lithium-ion batteries as flame retardant additive, and the self-extinguishing time and ionic conductivity were measured. The result showed that the compounds have effective flame retardant properties.

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An Investigation on the Comprehensive Property Assessment and Future Directions of Single Bamboo Fiber Reinforced Polypropylene Composites Fabricated by a Non-Woven Paving and Advanced Molding Process

Materials ◽

10.3390/ma12162641 ◽

2019 ◽

Vol 12 (16) ◽

pp. 2641 ◽

Cited By ~ 1

Author(s):

Tang ◽

Wang ◽

Cheng ◽

Guo

Keyword(s):

Thermal Stability ◽

Impact Strength ◽

Water Resistance ◽

Decomposition Temperature ◽

Modulus Of Rupture ◽

Gravimetric Analysis ◽

Molding Process ◽

Scanning Calorimetry ◽

Bamboo Fibers ◽

Thermal Stability Of

The demand for eco-friendly renewable natural fibers has grown in recent years. In this study, a series of polypropylene-based composites reinforced with single bamboo fibers (SBFs), prepared by non-woven paving and a hot-pressing process, were investigated. The influence of the content of SBF on impact strength, flexural strength, and water resistance was analyzed. The properties of the composites were greatly affected by the SBF content. Impact strength increased as SBF content increased. The modulus of rupture and modulus of elasticity show an optimum value, with SBF contents of 40% and 50%, respectively. The surface morphology of the fractured surfaces of the composites was characterized by scanning electron microscopy. The composites showed poor interfacial compatibility. The water resistance indicates that the composites with higher SBF contents have higher values of water absorption and thickness swelling, due to the hydrophilicity of the bamboo fibers. The thermal properties of the composites were characterized by thermal gravimetric analysis and by differential scanning calorimetry. The thermal stability of the composites was gradually reduced, due to the poor thermal stability of SBFs. In the composites, the maximum decomposition temperature corresponding to SBF shows an increasing trend. However, the maximum decomposition temperature of polypropylene was not influenced by SBF content. The melting point of the polypropylene in the composites was lower relative to pure polypropylene, although it was not affected by increasing SBF content.

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Thermal properties and thermal stability of polypropylene composites filled with graphene nanoplatelets

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717697777 ◽

2017 ◽

Vol 31 (2) ◽

pp. 246-264 ◽

Cited By ~ 13

Author(s):

JZ Liang ◽

JZ Wang ◽

Gary CP Tsui ◽

CY Tang

Keyword(s):

Thermal Stability ◽

Thermal Properties ◽

Weight Fraction ◽

Decomposition Temperature ◽

Graphene Nanoplatelets ◽

Filler Concentration ◽

Scanning Calorimetry ◽

Lateral Dimension ◽

Polypropylene Composites ◽

Thermal Stability Of

The thermal properties and thermal stability of polypropylene (PP) composites separately filled with graphene nanoplatelets (GNPs) with three different sizes were measured using a differential scanning calorimetry and a thermal gravimetric analyser. The results showed that the values of the melting temperature of the composites were higher than that of the unfilled PP; the thermal stability increased with increasing the weight fraction and lateral dimension of GNPs in the case of low filler concentration, while the effect of the GNPs thickness on the thermal stability was insignificant; the onset decomposition temperature increased with increasing the GNPs lateral dimension, while the maximum thermal decomposition rate increased first and then decreased with increasing the GNPs weight fraction. The thermal stability improvement should be attributed to the sheet barrier function of the GNPs.

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Effect of boric acid on thermal stability of poly (acrylonitrile-methyl acrylate)

e-Polymers ◽

10.1515/epoly.2009.9.1.155 ◽

2009 ◽

Vol 9 (1) ◽

Author(s):

Na Han ◽

Xingxiang Zhang

Keyword(s):

Thermal Stability ◽

Boric Acid ◽

Methyl Acrylate ◽

Gel Permeation Chromatography ◽

Decomposition Temperature ◽

Molar Ratio ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Molar Ratios ◽

Thermal Stability Of

AbstractA series of acrylonitrile(AN)-methyl acrylate (MA) copolymers (AN/MA) with molar ratios of 100/0-70/30 were synthesized by water depositing polymerization. One to three percent of boric acid (BA) was adopted as a stabilizer to enhance the thermal stability of AN/MA. The copolymers and the mixtures of copolymers treated with BA were characterized by using Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (1H NMR), Gel Permeation Chromatography (GPC), Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), X-ray diffraction (XRD) and Optic Microscope. The results show that melting point (Tm), glass transition temperature (Tg) and crystallinity of the copolymer decreased while decomposition temperature (Td) increased with the increase of MA content. Tm of AN/MA dropped to 174 °C and Td rose up to 321 °C when 15 mol% MA was incorporated. It was worthy to note that Tm of the copolymers increased conspicuously after being treated with BA. Stability of AN/MA with a molar ratio of 85/15 containing 1 wt% BA improved remarkably. The mixture can be kept stable up to 30 min at 220 °C.

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Study on the Thermal Stability of Polyphenylene Sulfide Filter Media by Non-Isothermal Thermogravimetry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.663.988 ◽

2013 ◽

Vol 663 ◽

pp. 988-992 ◽

Cited By ~ 2

Author(s):

De Qiang Chang ◽

Jing Xian Liu ◽

Ning Mao ◽

Bao Zhi Chen

Keyword(s):

Thermal Stability ◽

Degradation Kinetics ◽

Decomposition Temperature ◽

Polyphenylene Sulfide ◽

Thermal Degradation Kinetics ◽

Filter Media ◽

Initial Decomposition Temperature ◽

Isothermal Thermogravimetry ◽

Thermal Stability Of ◽

Better Than

In order to study the thermal stability of PPS (polyphenylene sulfide) filter media, by means of non- isothermal thermogravimetry, thermal degradation kinetics behavior of two kinds of PPS filter media were analyzed. The kinetic parameters of PPS filter media were obtained according to Friedman method. Thermal stability of PPS filter media was discussed. It was found that the initial decomposition temperature and activation energy of N3 sample are all higher than B1 sample, the thermal stability of N3 sample is better than B1 sample, and kinetic analysis can be used as an important method to evaluate the thermal stability of filter media.

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Thermal Stability of N-Heterocycle-Stabilized Iodanes – A Systematic Investigation

10.26434/chemrxiv.8964848 ◽

2019 ◽

Author(s):

Andreas Boelke ◽

Yulia A. Vlasenko ◽

Mekhman S. Yusubov ◽

Boris Nachtsheim ◽

Pavel Postnikov

Keyword(s):

Thermal Stability ◽

Differential Scanning Calorimetry ◽

Thermogravimetric Analysis ◽

Systematic Investigation ◽

Scanning Calorimetry ◽

Thermal Stability Of

The thermal stability of pseudocyclic and cyclic N-heterocycle-stabilized (hydroxy)aryl- and mesityl(aryl)-l3-iodanes (NHIs) through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is investigated. NHIs bearing N-heterocycles with a high N/C-ratio such as triazoles show among the lowest descomposition temperatures and the highest decomposition energies. A comparison of NHIs with known (pseudo)cyclic benziodoxolones is made and we further correlated their thermal stability with reactivity in a model oxygenation.

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A Characteristic Study of Polylactic Acid/Organic Modified Montmorillonite (PLA/OMMT) Nanocomposite Materials after Hydrolyzing

Crystals ◽

10.3390/cryst11040376 ◽

2021 ◽

Vol 11 (4) ◽

pp. 376

Author(s):

Su-Mei Huang ◽

Jiunn-Jer Hwang ◽

Hsin-Jiant Liu ◽

An-Miao Zheng

Keyword(s):

Thermal Stability ◽

Polylactic Acid ◽

Decomposition Temperature ◽

Material Strength ◽

Scanning Calorimetry ◽

Hydrolysis Process ◽

Twin Screw ◽

Thermal Pressing ◽

Organophilic Clay ◽

Mmt Clay

In this study, the montmorillonite (MMT) clay was modified with NH4Cl, and then the structures were exfoliated or intercalated in a polylactic acid (PLA) matrix by a torque rheometer in the ratio of 0.5, 3.0, 5.0 and 8.0 wt%. X-ray diffraction (XRD) revealed that the organic modified-MMT(OMMT) was distributed successfully in the PLA matrix. After thermal pressing, the thermal stability of the mixed composites was measured by a TGA. The mixed composites were also blended with OMMT by a co-rotating twin screw extruder palletizing system, and then injected for the ASTM-D638 standard specimen by an injection machine for measuring the material strength by MTS. The experimental results showed that the mixture of organophilic clay and PLA would enhance the thermal stability. In the PLA mixed with 3 wt% OMMT nanocomposite, the TGA maximum decomposition temperature (Tmax) rose from 336.84 °C to 339.08 °C. In the PLA mixed with 5 wt% OMMT nanocomposite, the loss of temperature rose from 325.14 °C to 326.48 °C. In addition, the elongation rate increased from 4.46% to 10.19% with the maximum loading of 58 MPa. After the vibrating hydrolysis process, the PLA/OMMT nanocomposite was degraded through the measurement of differential scanning calorimetry (DSC) and its Tg, Tc, and Tm1 declined.

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Isothermal Vulcanization and Non-Isothermal Degradation Kinetics of XNBR/Epoxy/XNBR-g-Halloysite Nanotubes (HNT) Nanocomposites

Materials ◽

10.3390/ma14112872 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2872

Author(s):

Seyed Mohamad Reza Paran ◽

Ghasem Naderi ◽

Elnaz Movahedifar ◽

Maryam Jouyandeh ◽

Krzysztof Formela ◽

...

Keyword(s):

Thermal Stability ◽

Degradation Kinetics ◽

Halloysite Nanotubes ◽

Butadiene Rubber ◽

Order Model ◽

Scanning Calorimetry ◽

Theoretical Methods ◽

Vulcanization Kinetics ◽

Kinetics Of ◽

Thermal Stability Of

The effect of several concentrations of carboxylated nitrile butadiene rubber (XNBR) functionalized halloysite nanotubes (XHNTs) on the vulcanization and degradation kinetics of XNBR/epoxy compounds were evaluated using experimental and theoretical methods. The isothermal vulcanization kinetics were studied at various temperatures by rheometry and differential scanning calorimetry (DSC). The results obtained indicated that the nth order model could not accurately predict the curing performance. However, the autocatalytic approach can be used to estimate the vulcanization reaction mechanism of XNBR/epoxy/XHNTs nanocomposites. The kinetic parameters related to the degradation of XNBR/epoxy/XHNTs nanocomposites were also assessed using thermogravimetric analysis (TGA). TGA measurements suggested that the grafted nanotubes strongly enhanced the thermal stability of the nanocomposite.

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