Symbolic image of calibration standards

SEC calibration standards

Kits with different molecular weight

Product overview

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Pullulan

Water-soluble polysaccharide

  • For aqueous SEC

  • Unbranched pullulan standard

  • High solubility in water eliminates the possibility of recrystallization

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Available as kit STANDARD P-82 with 8 different MW or also as single type STD P-series.

Polystyrene (PS)

Organic polymer

  • For organic solvent SEC (GPC)

  • Less branched polystyrene with anionic polymerization

  • Easily soluble in tetrahydrofuran (THF), chloroform, toluene, and o-dichlorobenzene (ODCB)

Available as three different kits for low, medium and high MW: STANDARD SL-105, SM-105, SH-75

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Polymethylmethacrylate (PMMA)

Organic polymer

  • For organic solvent SEC (GPC)

  • Narrow molecular weight distribution range

  • Easily soluble in hexafluoroisopropanol (HFIP) and dimethylformamide (DMF)

  • Also usable in THF, toluene, methyl ethyl ketone, ethyl acetate, DMF, DmAc

Available as kit STANDARD M-75 with 7 different MW

Chromatographic determinations of the molecular weight (MW) properties of polymers, either in organic or aqueous phase, rely on calibration with Standards of highly characterized MWs for accurate results.

 

Expressed simply, Size Exclusion (or Gel Permeation) Chromatography enables polymer molecules of different sizes in solution to be separated from one another, such that the large molecules elute first and small molecules elute last.

 

Since the molecular size in solution (hydrodynamic volume) is related to MW, a picture of the entire MW Distribution (MWD) may be obtained quickly and simply. This is in great contrast to the “absolute” techniques of MW determination which frequently could take half a day per sample to define a single average MW.


Polymer Standards are thus an integral part of any quantitative Size Exclusion Chromatography.

 

These Standards need to be highly characterized by as many absolute and chromatographic techniques as possible to define the MW averages and MWD. The closer the value of the MWD is to unity, the sharper will be the polymer peak and the better the material will be for a Calibration Standard.

Note: Molecular weights (Mp, Mw/Mn) of a standard kit or each single type may vary depending on production lots. Always refer to the inspection certificate.

Note: Safety Data Sheets (SDS) is available for these products.