Foundation GPC Part 5 – Polar and Aqueous Gel Permeation Chromatography Columns and Applications

2 Introduction  There are a wide variety of columns available for polar and aqueous GPC  This presentation shall introduce the most common types of column  This information can act as a reference  Applications on the various columns shall also be discussed  We have performed many applications on our columns, so even if your application is not shown here, we’ve probably done it!

3 Column Types  The factor that principally controls which type of column is selected for a GPC experiment is the solvent  Many polymer dissolve in only very limited numbers of solvents  The columns used must be compatible with the solvent of choice  Most importantly, the size exclusion mechanism must be maintained  Polymer Laboratories have one range of GPC column for aqueous solvents and one for any type of solvent  The properties of each range that must be considered when selecting them for an application shall be presented

4 Aqueous GPC  A growing number of polymers are water soluble  Interest in recycling, renewable resources and biomedical applications has led to increased interest in this area  There are lots of different chemistries of packing materials employed for aqueous GPC  Different manufacturers use different column types  Columns are available as individual or MIXED type and in a range of pore, particle and column dimensions, just like the organic GPC columns  We shall also discuss a new packing material that can be used in organic and aqueous solvents

5 PL Aquagel-OH Columns

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7 Typical Calibrants  Polyethylene glycol and oxide standards are chemically identical except for the end group  These are common polymer standards for aqueous GPC

8  For biological polymers such as starches and other polysaccharides, pullulans provide a more realistic result

9 Biopolymers Analysis  A thickening agent found in foodstuffs  The MIXED bed column is most suitable to this kind of broad polydispersity sample

10  A blood thickening agent, heparin is fairly low in molecular weight  For these types of samples the individual pore size columns are most suited

11 High Molecular Weight Analysis  High molecular weight samples are best analysed on individual pore size columns  The large particle size reduces the potential for shear degradation

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13 Analysis of Hydrophobic Polymers  Hydrophobic samples will interact in pure water  Methanol is added to the eluent to inhibit interactions

14 Analysis of Cationic Polymers  Cationic polymers require reduced pH to run  System imbalance peaks result from preparing the samples in a strong acid

15 Analysis of Hydrophobic, Anionic Polymers  These standards are anionic and hydrophobic  An increased pH and methanol are required for the analysis  WWater soluble polymers with a UV chromophore

16 PolarGel Columns

17 PolarGel Columns

18 PolarGel-M Calibrations

19 Peak Shapes of Polar Compounds

20 Analysis of Polar Samples  These materials can interact with PS/DVB columns  The more polar surface of PolarGel is well suited to this application

21 Analysis in Unusual Solvents  Acetone cannot be used for GPC with PS/DVB, the samples do not elute properly  The more polar surface of the PolarGel column allows GPC to be performed