Foundation GPC Part 4 – Organic Gel Permeation Chromatography Columns and Applications

1. Foundation GPC Part 4 – Organic Gel Permeation Chromatography Columns and Applications

2. Introduction • There are a wide variety of columns available for organic 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 two main ranges of GPC column for organic solvents • The properties of each range that must be considered when selecting them for an application shall be presented

4. Organic GPC • The vast majority of commercially important polymers are only soluble in organic solvents such as tetraydrofuran, toluene or trichlorobenzene • For these applications a column packed with material compatible with these solvents must be chosen • Almost universally columns packed with insoluble porous beads of polystyrene cross-linked with divinyl benzene are used (PS/DVB) • The majority of manufactures use columns of this type

5. Styrene/Divinyl Benzene Columns - PLgel

6. PLgel solvent Compatibility • Columns can be used in a wide range of solvents • Transfer between solvents is possible assuming care is taken • The column user guide details the procedure

7. Adsorption of Polystyrene Standards in DMF PS/DVB columns are excellent in many solvents, but remember that although the column may be used in certain solvents this does not mean SEC will occur - the example here is polystyrene standards running in DMF Column : PLgel 5um 500Å 300x7.5mm

8. PLgel Column Range • The extensive range of products has variation in pore size, particle size and column dimensions • The packing materials are identical in terms of surface chemistry

10. Low Molecular Weight High Resolution Separations • Individual pore size columns are ideal for these applications

11. Applications in Standard GPC Solvents • With no danger of shear degradation, 3um particles can be employed • Extremely high efficiency separations are obtained but only if the dispersion in the system is kept low

12. Combination of Individual Pore Size Columns Traditional approach to increasing MW operating range of column set

13. PLgel MIXED Bed columns

14. Individual Pore Size or MIXED Gel Columns? PLgel 5µm 10E4Å Optimum resolution over limited MW range Both types still have the similar pore volume, just the MW range over which it is available that changes PLgel 5µm MIXED-D Equal resolution over wider range of MW

15. Individual Pore Size Combination Versus MIXED Gel Columns - Calibration Data

16. Individual Pore Size Combination Versus MIXED Gel Columns - Polydisperse Sample Eluent THF Flow rate 1.0 ml/min Detector UV 254nm

17. PLgel MIXED Bed Calibrations

18. PLgel MIXED Bed Application Guide

19. Applications on MIXED Bed Columns • These samples are complex with polymer and oligomer components • MIXED columns with a wide resolving range are ideal in these cases

20. High Polarity Separations on PLgel • PLgel can be used with very polar solvents • Many samples can be analysed under these conditions

21. High Temperature Applications on PLgel • PLgel is very stable to high temperatures • The same material is used as for low temperature separations

22. Extreme GPC • In the most extreme case very high temperatures are required • The same PLgel material is employed even under these conditions

23. Unusual Peak Shapes in GPC • Not all peaks are Gaussian • Multimodal peaks are common in complex polymers • The presence of oligomers leads to complex chromatograms

24. Analysis of Multi-Component Systems • Interpreting the complex distributions of some samples can be challenging • Understanding the chemistry used to make the material is a definite help

25. Troublesome Applications on PLgel • Some applications are at the border of what is possible on PLgel columns • It may be that in these cases alternative packing materials will be required

26. PLgel LS Columns

28. PS/DVB miniMIX Columns

29. miniMIX Solvent Consumpsion

30. Applications with miniMIX Columns • Under the right conditions miniMIX columns perform just as well as their analytical counterparts

31. PS/DVB Preparative Columns

32. Comparative Preparative Separations • Preparative columns give identical chromatography to analytical columns under the right conditions • Method development can be performed on the analytical columns, reducing the risk of damage to expensive preparative coluns

33. PlusPore PS/DVB Columns

34. PlusPore Calibrations

35. Advantages of the PlusPore Range • With individual pore size columns dislocations are fairly common • The PlusPore range contains only one type of packing material with a wide resolving range • Dislocations cannot occur on this type of column

36. Effect of Increased Pore Volume Columns 2xPLgel 3µm 100Å 300x7.5mm 2xOligoPore 300x7.5mm Eluent THF Flow rate 1.0ml/min Both columns have a similar exclusion limit but OligoPore has greater pore volume than PLgel 100Å. Hence the slope of the curve is shallower leading to greater resolution for columns of the same efficiency

37. Applications in with PlusPore Columns • The extended pore volume of the PlusPore range leads to very high resolution

38. High Resolution OligoPore Separations • The OligoPore column if filled with 6um packing material, but due to a very large pore volume it gives resolution similar to a 3um PLgel • As a result of the larger particle size, OligoPore is very resilient to extra-column dispersion