Large‐scale polymer fractionation by gradient elution. Some operating principles

A detailed analysis of the factors operating in polymer fractionation by gradient elution column methods is offered. A comparison between experimental fractionations of a range of polystyrenes indicates that the most important single factor is the concentration of polymer permitted in the eluant. For the logarithmic composition gradient considered here, the average concentration in the eluant may be controlled through control of the volume of the eluant in the mixing vessel. This volume should be not less than 200 times the volume of the polymer sample, and considerably larger if the polymer is of high molecular weight.