Waters Styragel Columns - Manual (Page 2)

[ Care and Use ManUal ]
Styragel Columns 2
a. Waters Styragel HR
Use Waters Styragel HR columns for the high-resolution analysis of low-
molecular weight polymers, oligomers and additives. Packed with 5 µm
particles, Waters Styragel HR columns provide the high plate counts necessary
for this type of analysis.
b. Waters Styragel HT
Use Waters Styragel HT columns for the analysis of polymers with mid-range
molecular-weight distributions. They are the most versatile columns for
molecular-weight analysis. Waters Styragel HT columns are packed with 10 µm
particles to provide dependable performance over a wide range of temperatures
and solvents.
c. Waters Styragel HMW
Waters Styragel HMW columns are designed for the molecular-weight analysis
of ultrahigh-molecular-weight polymers. Their 20 µm particle size together with
the nominally 10 µm HMW frit design prevents the breakdown of ultrahigh
molecularweight polymers due to shear, which can occur with smaller particles.
This manual covers both column sizes 7.8 x 300 mm columns, and the solvent
efficient 4.6 x 300 mm columns. In sections with recommend flow rates or
spare parts, the 4.6 mm column conditions, or spare part follow immediately
after the 7.8 mm recommendations.
II. InstallIng the column Bank
This chapter describes:
• Preparing the GPC/HPLC system
• Installing the columns
• Repairing damaged compression screw assemblies
• Equilibrating the column
a. Preparing the GPC/HPLC System
Before attaching the columns in the flow path on a GPC/HPLC system, you
must first prepare the system:
1. Directly connect the system injector to the detector by replacing
the old columns with a zero-dead-volume union.
2. Convert the system to the solvent in which the columns have been
stored. For a new column set, this is the shipping solvent.
3. Flush the system to remove any microparticulates and old solvents.
Flush the injector loop if applicable.
Band spreading
The connection tubing and fittings in any chromatographic system contribute
to extra-column band spreading. Before installing the column, me sure your
system instrument band spreading (see Section on Testing Instrument Band
Spreading). If this test is not possible with your system, refer to your system
operator’s manual.
Narrow-Bore Chromatography for 4.6 mm Solvent Efficient Columns
The peak volume in a narrow-bore system is so small, it is critical to minimize
band spreading. Use the shortest tubing possible for all connections. It is not
necessary to use a microbore flow cell in your detector or to change your
conventional HPLC system in any way. Use 0.009-inch (0.25 mm) i.d. tubing
throughout the system.
b. Installing the Columns
When connecting columns in series, use the 0.009 inch (0.25 mm) i.d.
U-shaped column-joining tube supplied with each column.
Sequence of columns in a column bank
Generally, the results of an analysis are independent of the sequence in which
a column bank is arranged. However, to improve resolution and column life,
arrange the columns in order of decreasing pore size, with the column with
the largest pore size closest to the injector. This is recommended because:
• The columns with the larger pore sizes are more rugged and are
better able to tolerate the accumulation of extraneous materials.
• The species with the highest molecular-weight in the sample
contributes the most to the viscosity of the sample. If the largest
species is separated first, the viscosity decreases more quickly,
placing less strain on the column bank. In the case of ultrahigh MW
polymers, there is less shear on the sample.