36 1260 Infinity Micro Degasser Service Manual
4 Using the Micro Vacuum Degasser
Solvent Information
sulphuric acid > 10 %, trichloroacetic acid, sulfonic acids), halogenes or
aequous halogene solutions, phenol and derivatives (cresols, salicylic acid
etc.). When used above room temperature, PEEK is sensitive to bases and
various organic solvents, which can cause it to swell.
Polyimide
Agilent uses semi- crystalline polyimide for rotor seals in valves and needle
seats in autosamplers. One supplier of polyimide is DuPont, which brands
polyimide as Vespel, which is also used by Agilent.
Polyimide is stable in a pH range between 1 and 10 and in most organic
solvents. It is incompatible with concentrated mineral acids (e.g. sulphuric
acid), glacial acetic acid, DMSO and THF. It is also degraded by
nucleophilic substances like ammonia (e.g. ammonium salts in basic
conditions) or acetates.
Polyethylene (PE)
Agilent uses UHMW (ultra- high molecular weight)- PE/PTFE blends for
yellow piston and wash seals, which are used in 1290 Infinity pumps and
for normal phase applications in 1260 Infinity pumps.
Polyethylene has a good stability for most common inorganic solvents
including acids and bases in a pH range of 1 to 12.5 . It is compatible to
many organic solvents used in chromatographic systems like methanol,
acetonitrile and isopropanol. It has limited stability with aliphatic,
aromatic and halogenated hydrocarbons, THF, phenol and derivatives,
concentrated acids and bases. For normal phase applications, the
maximum pressure should be limited to 200 bar.
Tantalum (Ta)
Tantalum is inert to most common HPLC solvents and almost all acids
except fluoric acid and acids with free sulfur trioxide. It can be corroded
by strong bases (e.g. hydroxide solutions > 10 %, diethylamine). It is not
recommended for the use with fluoric acid and fluorides.
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