Poly styrene-divinylbenzene Backbone PS-DVB

The major commercial anion exchangers for ion chromatography are based on two substrate types macroporous and microporous (or gel-type) materials. Microporous substrates are used primarily as supports for pellicular, latex-coated beads. This type of column is efficient and versatile. Many different column types with different selec- 

The substrate polymer beads used in this work are quite hard and do not swell and shrink when the solvent is changed. A measure of bead hardness is given by the swelling propensity value. This value is obtained by measuring the backpressure of a column with a tetrahydrofuran mobile phase and then with an aqueous phase. After correcting the eluent backpressure for viscosity, the swelling propensity, SP, is calculated by the following equation  

An SP value of 0 indicates non-swelling material. The substrate used in this work had an SP of 0.8. Silica-based substrates are hard and typically have SP values of 0.05. However, other PS-DVB resins often have SP values well above 1.0. Columns packed with the ANl resin have given excellent separations of common anions using a variety of eluents. 

Polymeric resins from Hamilton have been used extensively for anion chromatography. Their PS-DVB anex resins contain trimethylammonium groups. PRP XlOO has 

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