AZURA® Detector RID 2.1L / RID 2.1L HighFlow Instructions V6750
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Product information
stances, such as additives, modifiers, or salts can influence the durability
of the materials. Exposure time and concentration have a high impact on
the resistance.
The following list contains information about the chemical compatibility
of all wetted materials which are used in devices made by KNAUER. The
data bases on a literature research on the manufacturer specifications of
the materials. The wetted materials of this device are listed in the chapter
"Technical data".
All resistances mentioned here are for use at temperatures up to 40 ° C,
unless stated otherwise. Please note that higher temperatures can signifi-
cantly affect the stability of different materials.
12.2 Plastics
Polyetheretherketone (PEEK)
PEEK is a durable and resistant plastic and, next to stainless steel, the
standard material in HPLC. It can be used at temperatures up to 100 °C
and is highly chemical resistant against almost all commonly used sol-
vents in a pH range of 1-12,5. PEEK is potentially moderate resistant
against oxidizing and reducing solvents.
Therefore, following solvents should not be used: Concentrated and oxi-
dizing acids (such as nitric acid solution, sulfuric acid), halogenated acids
(such as hydrofluoric acid, hydrobromic acid) and gaseous halogens.
Hydrochloric acid is approved for most applications.
In addition, following solvents can have a swelling effect and may have an
impact on the functionality of the built-in components: Methylene chlo-
ride, THF and DMSO in any concentration such as acetonitrile in higher
concentrations.
Polyethylene terephthalate (PET, outdated PETP)
PET is a thermoplastic and semi-crystalline material with high wear resis-
tance. It is resistant against diluted acids, aliphatic and aromatic hydrocar-
bons, oils, fats and alcohols, but not against halogenated hydrocarbons
and ketones. Since PET belongs chemically to esters, it is not compatible
with inorganic acids, hot water and alkalis. Maximum operating Tempera-
ture: up to 120 °C.
Polyimide (Vespel®)
This material is wear-resistant and permanent resilient thermically (up to
200 °C) as well as mechanically. It is chemically broadly inert (pH range
1-10) and is especially resistant against acidic to neutral and organic
solvents, but vulnerable to pH strong chemical or oxidizing environments:
It is incompatible with concentrated mineral acids (such as sulfuric acid),
glacial acetic acid, DMSO and THF. In addition, it will be disintegrated by
nucleophilic substances like ammonia (such as ammonium salts under
alkaline conditions) or acetate.
Ethylene-tetrafluorethylene copolymer (ETFC, Tefzel®)
This fluorinated polymer is highly resistant against neutral and alkaline
solvents. Some chlorinated chemicals in connection with this material
should be handled with care. Maximum operating Temperature is 80 ºC.
