Solvent, effect, thermal instability

Therefore, the presence of the electrolyte solute, LiPFe, added complexity to the thermal decomposition of the LiMn204-based cathode. Contrary to the salt effect found with the LiCo02 cathode, the onset temperature of exothermic activity as represented by SHR > 0.02 °C min decreased as the concentration of LiPFe increased. Apparently, LiCo02 and LiMn204 have fundamental differences in the way they react with solvent in the presence of salt. It seemed that the salt mainly contributes to an initial thermal instability, which increases with LiPFe-concentr ation. ... 

The increase in the molar conductivity, corrected for viscosity effects, with increasing I2 content of MI (M = Me4N, Et4N, BU4N, or Na) in I2-DMF solutions and of Nal in I2-DMSO solutions has been attributed to the so-called relay conduction mechanism of 1 ions in I2 solutions."" These results support the proposal made earlier that the lower, but normal conductivities of Nal in liquid I2 are due to the thermal instability of Na I(l2)n- The formation of I3 has been studied spectrophotometrically in MeOH, Pr OH, Bu OH, MeCN, and DMSO" and in mixtures of these solvents both with and without water. 

Liquid modifiers that are commonly used to increase the effective polarity of supercritical fluids such as carbon dioxide frequently have inherent chemical instabilities that must be considered when designing an analysis, or in the interpretation of results.1-3 In many cases, such solvents are obtainable with stabilizers added to control the instability or to slow the reaction. Reactive solvents that do not have stabilizers must be used quickly or be given proper treatment. In either case, it is important to understand that the solvents (as they may be used in an analysis) are not necessarily pure materials. The reader is cautioned that many of the other fluids listed earlier in this section are thermally unstable this table only treats chemical instabilities that are considerable at typical laboratory ambient temperature. 

Reactive extrusion is a new tool in polymer reaction engineering. From an environmental viewpoint, the need for only small quantities of volatile solvents, and consequent reduced cost, are positive aspects. From an economical point of view, the expensive extrusion equipment is compensated by there being no need to separate the polymer from the solvent The process is largely complicated by the occurrence of various nonlinear effects that may introduce instabilities into the process, these being of thermal, hydrodynamic, and chemical origin. 

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