Paraffin compounds, melting points

Thus, if there is a need to reduce the melting point of a nitro compound, e.g. picric acid, other nitro compounds are added to form an eutectic mixture to decrease the sensitiveness of picric acid to mechanical impact it is mixed with paraffin. 

Use a liquid paraffin bath or electrical heating apparatus to measure the melting point of an unknown compound and decide whether it is a pure sample. 

The odd-even alternations displayed in half of the above studies (Figs. 29 and 31) are not yet fully understood. It is well known [166] however, that the molar refractions of Z(CH2) H liquids exhibit odd-even alternation, and a variety of paraffin chain compounds [167] exhibit odd-even alternation in their melting points and heats of fusion, which of course also involves transition from the solid crystalline state to the liquid state. Such alternations have also been exhibited in... 

One of the earliest separations in gas liquid chromatography was that of James et al. who used a mixture of hendecanol and liquid paraffin on celite using ammonia and the methyl amines as eluents in the order of their melting points. Other stationary phases used for this and for other similar separations include triethanolamine, a mixture of w-octadecane and n-hendecanol, and polyethylene oxide. Titration cell, the first detector designed specifically for gas chromatography, was used in these early studies of the separation of ammonia and ethylamines. More recently thermal conductivity cells have been used for the detection of these compounds. 

The difference between plasticizers and tackifiers is somewhat arbitrary and the effect of this difference is described below in the section on Physical Properties. Plasticizers are typically lower in molecular weight and melting or softening point than are tackifiers. Hydrocarbon oils including aromatic, naphthenic, and paraffinic are commonly used with rubber-based adhesives. Phthalates, such as dioctyl phthalate or dibutyl phthalate, are more typically used in small amounts with acrylics. Since plasticizers are usually low molecular weight compounds, there is often more latitude in the chemical types that will be compatible with the base pol5mier because of the contribution from entropy of mixing. 

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