Solubility testing

Group I. This includes the lower members of the various homologous series (4-5 atoms in a normal chain) that contain oxygen and/or nitrogen in their structures they are soluble iu water because of their low carbon content. If the compound is soluble in both water and ether, it would also be soluble in other solvents so that further solubility tests are generally unnecessary the test with sodium bicarbonate solution should, however, be performed (see Section XI,6). 

Fuels such as diesel and kerosene readily absorb hydrocarbon vapors, the total uptake and absorption rate depending on both chemical and physical factors. If a soluble test gas is introduced above a charged test oil the concentration of flammable test gas therefore decreases with time. Liquid mist and spray produced by charged liquid increase the absorption rate relative to a quiescent liquid surface. As discussed in A-5-4, absorption could lead to an underestimation of test gas MIE near the liquid surface unless the rate of test gas introduction is sufficiently high to offset the rate of removal. Table 3-8.1.2 shows solubilities of a selection of gases in a mineral-based transformer oil at ambient temperature and pressure [200]. 

The solubility test consists of dissolving l.OOOg of the specimen in 20ml of w. If the soln is not completely clear or possesses more than a very slight opalescence, the specimen does not comply with the requirement... 

Initially, the co-agents were mixed with PVDF and FMVQ separately and the mixtures were subjected to mild irradiation. Solubility tests indicated no cross-hnking during this operation. The polymeric components were then mixed in the presence of CaO/MgO in a Brabender plasticorder at a rotor speed of 60 rpm at 160°C. Subsequently, the temperature was lowered to 130°C and a 0.2% benzoyl peroxide paste was added. Mixing was continued for 10 more minutes. Cure characteristics... 

Polymer-solvent interactions and solubility testing were summarised by Staal [26]. 

Dye solubility test A colored dye soluble in only one component is added to the emulsion. If the color spreads throughout the whole emulsion, the phase in which the dye is soluble is the continuous phase. 

Well, that just about concludes our brief look at solvents. If you can t dissolve it in one of the common solvents, you ve got problems. If in doubt, try a bit first, before committing your entire sample. Use nondeuterated solvents for solubility testing if possible, as they are much cheaper. 

The visual inspection of XX vials cut open does not show any sign of skin on the cake surface and of collapsed inclusion near the bottom of the vial. The solubility test, described in directive (p) shall be satisfactory for the dried product in all vials tested. 

If your compound does not happen to dissolve in CC14, you still have a shot because deuterium atoms do not give PMR signals. This is logical, since they re not protons. The problem is that deuterated solvents are expensive, so do NOT ask for, say, D20 or CDC13, the deuterated analogs of water and chloroform, unless you re absolutely sure your compound will dissolve in them. Always use the protonic solvents — H20 or CHC13 here — for the solubility test. There are other deuterated solvents, and they may or may not be available for use. Check with your instructor. 

Aminoacid analysis and solubility tests for crosslinking revealed that XLC participated in various reactions leading to crosslinked wool [144] -... 

From the behavior on precipitation of the copolymers prepared by the three different methods, it may already be suspected that, In spite of the common starting mixture, one is dealing with different kinds of polymer. In order to prove this the following solubility tests are carried out. 

Solvents 1 and 2 are known to be good solvents for poly(methyl methacrylate) solvent 3 readily dissolves polystyrene.The solubility tests show that the radically polymerized sample is insoluble in all three solvents.The solubility isthusdifferentfrom that of both poly(methyl methacrylate) and polystyrene.The anionically polymerized product dissolves on warming in the acetone/methanol mixture and also in acetonitrile it is insoluble in cyclohexane/toluene.The solubility is thus similar to that of poly(methyl methacrylate). For the cationically initiated polymerization the product is only slightly soluble in acetone/methanol, insoluble in acetonitrile, but very readily soluble in cyclohexane/toluene.The solubility thus resembles that of polystyrene. 

In addition to the solubility tests, the structures of the polymers can be determined easily from the IR and H-NMR spectra. 

One may first check qualitatively whether the desired reaction has taken place, especially by means of solubility tests and NMR or IR spectroscopy it is also necessary to examine whether unreacted groups, or groups other than those desired, are present. Quantitative analysis is aimed at evaluating the proportions of A, C, and D in Eq. 5.2, for which one may employ not only the usual methods of determination, but also special procedures, such as spectroscopy and pyrolysis gas chromatography. It is also sometimes expedient to choose the low-molecular-weight reactant so that an easily determinable element is introduced (e.g., by using chloroacetic acid for esterifications). 

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