general reference
100
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VICIAG International
Properties ofmaterials Polymers andmetals
Stainlesssteel,Type316
This is the standard tubingmaterial for
chromatography,suitable for awidevariety
of applications. It is colddrawn seamless,not
welded,withclose tolerancesheldonboth ID
andOD.Weneither recommendnorofferType
304 stainless steel for analytical applications.
Austenitic stainless steelsmaybeused for
most chromatographicapplications.Type316
ismost commonlyused forHPLCbecauseof its
superior chloride ion resistance.
Stainlesssteel,Type303
Recommended forGCuseandgeneral
purposeconnections,combiningexcellent
machiningcharacteristicswithgood resistance
tocorrosionandhigh temperatureoxidation.
Susceptible toattachbychlorides, iodides,and
bromides.
Properties ofmetals
Titanium
Although it ismoredifficult tomachine than
commonalloys containingaluminumand
vanadium,VICI usesGrade2pure titanium in
order toavoidpossiblecontaminationof the
sample streamwith thesemetals.Good for
organicand inorganic saltsexcept aluminum
andcalciumchlorides,andall alkalisexcept
boilingconcentratedpotassiumhydroxide.
Goodwithdilute, low temperature formic,
lactic,sulfuric,hydrochloric,andphosphoric
acids,but rapidlyattackedbyhydrofluoric
acid.Goodwithdilutenitricacidat low
temperatures;corrodesathighconcentrations
and temperatures.Can ignitewith fumingnitric
acid.Attackedbyoxalicacid,concentrated
phosphoricacid,hot trichloroaceticacid,and
zincchloride.
Polyamide
Polyamide isa thermoplasticpolymer also
knownasnylon.Nylonhasverygoodphysical
properties,butmoisturecanhavea significant
effect. It exhibitsverygoodheat resistanceand
excellent chemical andwear resistance.
Polyethylene
Polyethylene isa semi-crystallinematerial
withexcellent chemical resistance,plusgood
fatigueandwear resistance.Polyethylenes
providegood resistance toorganic solvents
and staining,andhave lowmoistureabsorption
rates.
Polypropylene
Widelyusedpolymer fornon-wettedparts.
Attackedby strongoxidizersaswell asaromatic
andchlorinatedhydrocarbons.
PVDF
PVDF,orpolyvinylidenefluoride,hasexcellent
resistance tomostmineral andorganicacids,
aliphaticandaromatichydrocarbons,and
halogenated solvents.Poor resistance to
acetone,MEK,THF,andpotassiumand sodium
hydroxide.Often suppliedasKynar®.
