Phase distribution chromatography (PDC) as a method for the investigation of polymers in solution, 3. Determination of narrow molecular weight distributions

Abstract

Phase distribution chromatography (PDC) is demonstrated to be a powerful method for the correct determination of narrow molecular weight distributions. This is shown by comparing the molecular weight distributions (MWD) of polystyrenes obtained from PDC measurements with those obtained by Baker-Williams fractionation and by gel permeation chromatography. Four problems are formulated and analyzed which are closely connected with the calculation of the MWD from a measured PDC-elution curve at temperatures below the theta point of the system. Thus, the theory of PDC outlined previously is tested.

Phase distribution chromatography (PDC) as a method for the investigation of polymers in solution, 4. Deformation concept

“…e. g. Flory') yields the well-known expressions (4) giving Hooke's law for small linear deformations with 1 = 1, i.e. e. g. Flory') yields the well-known expressions (4) giving Hooke's law for small linear deformations with 1 = 1, i.e.…”

Separation of linear and star‐shaped polystyrenes by phase distribution chromatography

“…However, temperatures lower than this are used for better separation results, due to the solubility of UHPS and the low resolution near to this region 15. The theoretical background of PDC was extensively investigated and explained by Greschner 16–20 including the thermodynamics of molecular transport, the flow equilibrium and the deformation concept.…”