Solvent suitability

The polymers dissolve in l,l,l,3,3,3-hexafluoro-2-propanol [920-66-1/, hot phenols, and /V, /V- dim ethyl form am i de [68-12-2] near its boiling point. The excellent solvent resistance notwithstanding, solvents suitable for measurement of intrinsic viscosity, useflil for estimation of molecular weight, are known (13,15). 

In general, those properties of industrial interest that are related to the electrochemical rates change several orders of magnitude when the conditions of synthesis are improved and when a solvent suitable for the specific application is used to produce the polymeric gel. We found this to be the case in our laboratory between the first and second generation of artificial muscles, with electrochromic films, or with specific energies. 

All previous discussion has focused on sample preparation, i.e., removal of the targeted analyte(s) from the sample matrix, isolation of the analyte(s) from other co-extracted, undesirable sample components, and transfer of the analytes into a solvent suitable for final analysis. Over the years, numerous types of analytical instruments have been employed for this final analysis step as noted in the preceding text and Tables 3 and 4. Overall, GC and LC are the most often used analytical techniques, and modern GC and LC instrumentation coupled with mass spectrometry (MS) and tandem mass spectrometry (MS/MS) detection systems are currently the analytical techniques of choice. Methods relying on spectrophotometric detection and thin-layer chromatography (TLC) are now rarely employed, except perhaps for qualitative purposes. 

Restricted selection of solvents (suitable for host polymer and additives and deformulation technique)... 

This is a very polar solvent, suitable for salts and extremely polar compounds. Like DMSO it has a very high affinity for water and is almost impossible to keep dry. Its water peak is sharper and occurs more predictably at around 4.8 ppm. The residual CD2HOD signal is of similar appearance to the D6-DMSO residual signal and is observed at 3.3 ppm. 

The synthetic route generally involves condensing two equivalents of 4,5,6,7-tetrachloroisoindoline-l-one derivatives with one equivalent of an aromatic diamine in an organic solvent. Suitable tetrachloroisoindoline-l-one derivatives are substituted in 3-position, which is occupied either by two monovalent groups (A)... 

S.No. Solvent Suitable for Solute Type Upper Temp. Limit (°C)... 

Most of the isolated diacyl (including sulfonyl) peroxides are solids with relatively low decomposition temperatures, and are explosive, sensitive to shock, heat or friction. Several, particularly the lower members, will detonate on the slightest disturbance. Autocatalytic (self-accelerating) decomposition, which is promoted by tertiary amines, is involved [1]. Solvents suitable for preparation of safe solutions of diacetyl, dipropionyl, diisobutyryl and di-2-phenylpropionyl peroxides are disclosed [2], The class is reviewed, including hazards and safety measures [3], Cyclic diacyl peroxides are more stable, but scarcely to be trusted. Individually indexed compounds are ... 

In general, ESI can be well applied to ionic metal complexes and related compounds if these are soluble to at least 10" M in solvents suitable for the method. [18,19] Whether conventional or nanoESI should be employed basically depends... 

Polymers fall into one of two major classes, thermoplastics, and thermosets. Despite the fact that thermosets have been around much longer, thermoplastics make up about 80% of the industry output. Thermoplastics are linear polymers that can be resoftened a number of times, usually by applying heat and pressure. They can be dissolved in solvents (suitable for that purpose). That s not true for thermosets once they re set. After they re formed or cured (by heat and/or pressure), these cross-linked three-dimensional polymers become nonmelting and insoluble. Thermosets actually decompose under heat before they melt. 

Reverse osmosis procedures concentrate over 90% of the total organic material present in water into an aqueous brine (29). A problem has been the efficient transfer of the organic components to a solvent suitable for the bioassays (30). Another problem is the loss of chemicals having molecular weights below 200-400. 

Wash the cartridge with a solvent suitable for initial conditions. 

Some people find the effects of solvents on the nervous system desirable and purposely inhale (sniff) solvents to induce a form of intoxication. In the United States approximately 15% of high school students have tried solvent inhalation at least once. Solvents suitable for inhalation and abuse are common in the home. Home products that may contain solvents include paints, paint remover, varnishes, adhesives, glues, degreasing and cleaning agents, dyes, printing ink, floor and shoe polishes, waxes, pesticides, drugs, cosmetics, and fuels, just to name a few (Table 11.1). 

Solvents suitable for electrospray have to meet two important require-... 

Bonnesen, F. V., Delmau, L. H., Moyer, B. A., Leonard, R. A., A robust alkaline-side CSEX solvent suitable for removing cesium from Savannah river high level waste, Solv. Extr. Ion Exch., 18, 1079-1107,2000. 

In a similar way, one can achieve the separation according to functionality in other solvent mixtures, e.g. chloroform-acetone (Fig. 17). Except of slight differences in retention times for molecules of different functionality, which can be caused either by the difference in the interaction in the mobile phase or a change in the water content of the adsorbent, the form of FTD chromatograms for both eluents at critical conditions is similar. This indicates that for the critical conditions to be realized it is sufficient to have any two solvents suitable for the detection method, one of which works in the exclusion and the other in the adsorption mode. 

One of the most comprehensive reviews on solvent use and purification was prepared by C.K. Mann [13]. Many solvents are discussed, and for each particular solvent, suitable supporting electrolytes and reference electrodes are presented. Lund and Iversen [65], among others [66], have also surveyed the use, purification, and properties of solvents. There are overlaps among all of these reviews and the present one, but each has its own special flavor and the different viewpoints make for instructive comparisons. There are also a number of articles devoted to specific solvents, such as DMSO [62,67], DMF [68], methylene chloride [69], and pyridine [70]. 

It must be emphasised that there is no universal cleaning mixture. The chemist must take into account the nature of the substance to be removed and the amount of deposit, and act accordingly. Thus if the residue in the flask is known to be basic in character, dilute hydrochloric or sulphuric acid may dissolve it completely similarly, dilute sodium hydroxide solution may be employed for acidic residues. In these instances the acidic or basic aqueous solution may be washed down the drain with liberal quantities of water. If the residue is known to dissolve in an inexpensive organic solvent, this should be employed in such a case the solution must be poured into the appropriate residues bottle, not down the sink. Solvent suitable specifically for cleaning use may be recovered by distilling accumulated residues. Remaining heavily contaminated material should be suitably disposed of (Section 2.1, p. 30). 

For a theoretical treatment involving association or dissociation in one solvent, suitable texts should be consulted.43,44... 

Selection of solvents for adsorption chromatography. The choice of solvent for transferring the mixture to be chromatographed to the column will naturally depend upon the solubility characteristics of the mixture. If it is already in solution, for example as an extract, this is usually evaporated to dryness under reduced pressure and the residue dissolved in the minimum volume of the most non-polar solvent suitable. As concentrated a solution as possible is desirable to achieve a compact band at the top of the column of adsorbent, so that during subsequent development the separation will hopefully proceed with formation of discrete bands. 

Bonnesen, P. V., L. H. Delmau, B. A. Moyer, and R. A. Leonard. 2000. A Robust Alkaline-Side CSEX Solvent Suitable for Removing Cesium from Savannah River High Level Waste. Solvent Extr. IonExch. 18(6), 1079-1107. 

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