Home » Gel permeation chromatography, Tech Talk, Viscotek

The Chromatogram Series: Polystyrene (PS)

26 September 2013 No Comment

Written by:

Here is an example chromatogram of polystyrene in THF. The run conditions and some results are detailed in the table below.

Wikipedia: Polystyrene is a synthetic aromatic polymer made from the monomer styrene, a liquid petrochemical. Polystyrene can be rigid or foamed. General purpose polystyrene is clear, hard and brittle. It is a very inexpensive resin per unit weight. Uses include protective packaging (such as packing peanuts and CD and DVD cases), containers (such as “clamshells”), lids, bottles, trays, tumblers, and disposable cutlery.

Solvent THF
Flow Rate [mL/min] 1.000
Column Set 2 x T6000M
Column Temp (°C) 30.0
Injection volume μL 100.0
Concentration [mg/mL] 1.177
Mw Weight Average [Da] 99,149
Sample dn/dc [mL/g] 0.185
Sample IV [dL/g] 0.4768
Chromatogram of Polystyrene in THF

Chromatography trace of refractive index RI, low angle LALS, right angle RALS light scatteirng, and viscosity versus retention volume of Polystyrene in tetrahydrfuran THF

This is a typical narrow polystyrene (often also abbreviated as PS) sample of the type that is used to calibrate the system for inter-detector delay, band broadening and detector constants. Polystyrene standards are available in convenient “just add solvent” kits for easy use in chromatography.

In this data set, both the 7º (LALS) and 90º (RALS) light scattering signals show very little noise due to the clean nature of the sample. There is a slight trend in the RI signal due to temperature equilibration.

Previously

If you have any questions, please email me at ulf.nobbmann@malvern.com. Thanks!