Aliphatic hydrocarbons n-hexane

Aliphatic hydrocarbons n-hexane, cyclohexane, and n-heptane Aliphatic hydrocarbons are nonpolar. Their solubility in water is virtually nil. They are less dense than water, and thus would be the top layer in a separatory funnel with a water solution. They are obviously poor solvents for polar compounds, but are very good for extracting traces of nonpolar solutes from water solutions. They are highly flammable and have a low toxicity level. 

The sorption and transport of four aliphatic hydrocarbons (n-hexane, n-heptane, n-octane and n-nonane) into NR crosslinked using conventional, efficient, dicumyl peroxide(DCP) and mixed sulphur/peroxide vulcanisation systems were investigated at temp, of 28 to 60C. The NR vulcanised by DCP exhibited the lowest penetrant uptake of the systems studied. It was observed that the kinetics of liquid sorption in every case deviated from the regular Fickian trend, characteristic of sorption of liquids by rubbers. The diffusion coefficient, activation energy of sorption, enthalpy, entropy and rubber-solvent interaction parameter were evaluated for the four systems from the swelling data. 30 refs. 

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