Polymer Standards for Size Exclusion Chromatography
in Organic solvents (for hydrophobic molecules)
Calibration in THF, Toluene, Xylene
The standard reference polymers that are soluble in organic solvents such as tetrahydrofurane, toluene, xylene, etc, are used for instrument calibration or quality control during the performance of Size Exclusion Chromatography (SEC) tests of molecules insoluble in water.
The following standards are used for calibration of non polar (hydrophobic) polymers
Calibration in DMAc, DMF and DMSO
Polymers that present polarity are most often analized in polar mobile phases such as n,n-DIMETHYLACETAMIDE (ACETIC ACID, DIMETHYLAMIDE) (DMAc) ; Dimethylformamide (DMF) and dimethyl sulfoxide (DMSO).
The following standards are also available at PSS for calibration with polar solvents
Nylon 6 Broad
Poly(vinyl pyrrolidone) broad
Most common Narrow standards of Poly(methylmethacrylate) run with PSS Gram columns.
Size Exclusion Chromatography (SEC) calibrations in these solvents usually perform better when the calibration molecule shows a siimilar degree of polarity
By far the most commonly used are Narrow standards of Polystyrene, run through hydrophobic columns such as the PSS SDV columns.
The majority of neutral (non polar) testing systems in organic solvents; copolymers, and resins. can be initially separated and charavterized by molecular weight using either a Refractive Index (RI) or an Ultra Violet (UV) detector.