Meaning and Use

4.1 The control of water content is generally important for controlling the performance of paints and paint components, as well as for controlling the content of volatile organic compounds (VOC).

4.2 Coatings are generally insoluble in common Karl Fischer solvents such as methanol. Pyridine has been found to be an almost universal solvent for these materials. However, the Karl Fischer reaction in this solvent is too slow at room temperature. To speed things up, 1-ethyl piperidine was added at a concentration of 5% as a buffer or “catalyst”.

4.3 For nonpyridin-based reagents, many different solvent systems can be used to increase solubility and minimize ketone and aldehyde interference.

ASTM D4017-02-2015 Standard Test Method for Determination of Water in Paints and Paint Materials by the Karl Fischer Method

Scope

1.1 This test method is applicable to all paints and coatings, including resins, monomers and solvents, except aldehydes and certain active metals, metal oxides and metal hydroxides. Although the evaluation is limited to colored products with water content in the range of 30% to 70%, there is reason to believe that higher and lower concentrations can be determined by this test method.

1.2 Values expressed in SI units shall be considered standard. The values given in parentheses are for reference only.

1.3 This standard is not intended to address all safety issues related to use. It is the responsibility of the user of this standard to establish appropriate safety and health measures prior to use and to determine the applicability of regulatory restrictions. The specific harm specification is given in Section 7.

ASTM D4017-02-2015 Standard Test Method for Determination of Water in Paints and Paint Materials by the Karl Fischer Method

2. Refer to documents

ASTM standard

D1193 Reagent water specification

D3960 Method for determination of volatile Organic Compounds (VOC) content in paints and related coatings

E180 Practice for determining the accuracy of ASTM methods for the analysis and testing of industrial and specialty chemicals

E203 Method for testing water using Karl Fischer volumetric titration