Determination of Water Content in Epoxy styrene Using Karl Fischer Titration

Product Group

Ethers, Technical products

General Information concerning the product group

Ethers

In most cases ethers can be determined after Karl Fischer standard methods analogously to hydrocarbons. Long-chain compounds require the addition of solubilisers, e.g. long-chain alcohols or chloroform. Recommended methods are both, the volumetric titration with one or two component reagents, as well as the coulometric analysis. The latter is predominantly applied for low water concentrations (< 0.1 %). One exception are the vinyl ethers, which cause an interfering side reaction with methanolic Karl Fischer reagents.

Technical products

This product group comprises the most diverse products. Depending on solubility, their behaviour in the KF solution and water content, different Karl Fischer methods apply.

Special Information concerning the sample and the methods

This substance is easily soluble in alcoholic media. Side reactions may, however, occur in the Karl Fischer solution. Therefore, only volumetric analysis is recommended.

Titration one component system

Reagents:

Titrant
188002 Aquastar™ - CombiTitrant 2 - One component reagent for volumetric Karl Fischer titration, 1 mL = approx. 2 mg water

Solvent
50 mL 188008 Aquastar™ - CombiSolvent - Methanol-free solvent for volumetric Karl Fischer titration with one component reagents
or
50 mL 188009 Aquastar™ - CombiMethanol - Solvent for volumetric Karl Fischer titration with one component reagents, max. 0.01 % water

Titration Parameters:
Default titration settings, e.g.:
I(pol) = 20 - 50 µA, U(EP) = 100 - 250 mV
Stop criterion for fast titration: drift < 30 µL/min

Sample size:
2 mL

Procedure:
The titration medium is first placed into the cell and titrated dry by means of the titrant. Then the sample is added with a syringe (exact sample weight determination by weighing of syringe before and after injection) or volumetric pipette and the titration is started. Titration is carried out to fast end point.

Titration two component system

Reagents:

Titrant
188011 Aquastar™ - Titrant 2 - Titrant for volumetric titration with two component reagents, 1 mL = approx. 2 mg water

Solvent
50 mL 188015 Aquastar™ - Solvent - Solvent for volumetric titration with two component reagents

Titration Parameters:
Default titration settings, e.g.:
I(pol) = 20 - 50 µA, U(EP) = 100 - 250 mV
Stop criterion for fast titration: drift < 30 µL/min

Sample size:
2 mL

Procedure:
The titration medium is first placed into the cell and titrated dry by means of the titrant. Then the sample is added with a syringe (exact sample weight determination by weighing of syringe before and after injection) or volumetric pipette and the titration is started. Titration is carried out to fast end point.

Materials

     
Related Links