Properties of decalin as a solvent in thermal field-flow fractionation

Cis-trans-decahydronaphthalene (67.85 % trans + 32.15 % cis, here briefly referred to as cis-trans-decalin) as a possible solvent for thermal field-flow fractionation is proposed. Different features such as solvent properties with respect to low polarity polymers, availability of basic physicochemical data (viscosity and thermal conductivity in a convenient temperature range), low toxicity and low cost are emphasized. Retention data over a wide range of cold wall temperatures and thermal gradients were collected. The nu correction factor and lambda retention data were determined for polystyrene samples over a relative molecular mass range of 11,300-3,950,000 g mol(-1) From these data, selectivity values were determined and compared to the commonly found values for polystyrene in different solvent systems. The average value of -0.6 found here for cis-trans-decalin falls in the optimum selectivity solvent-domain. Cis-trans-decalin is thus fully proven as an optimum solvent for ThFFF.