ISO 8130-6 pdf free download
ISO 8130-6-2021 pdf free download.Coating powders一 Part 6: Determination of gel time of thermosetting coating powders at a given temperature.
This document specifies a method for determining the time for a thermosetting coating powder to gel at a specified temperature. A method is described for checking batch to batch variation and for the quality control of a given coating powder.
The method is not applicable to coating powders with ultra-short gel times (less than 15 s).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 8 130-14, Coating powders — Part 14: Vocabulary
ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 8130-14 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
3.1 gel time
time taken for a specified volume of coating powder to become non-deformable, under specified conditions, after melting
4 Principle
A test portion of a coating powder is heated to a specified temperature in a depression of a heating block. The time at which threads can no longer be pulled from the molten product is determined.
5 Materials
5.1 Test substances, of known melting point for checking the temperature of the heating block (J).
For a test temperature of 180 °C, a suitable material should be chosen which shall not interfere with the subsequent analysis.
6.5 Stirrer, of very low heat capacity and of suitable size.
A stirring needle with a round pinhead, diameter 1 mm, and attached to an insulating handle may be used.
NOTE A wooden stirrer has also been found to be satisfactory.
6.6 Scraper, made of a material softer than that of the heating block, for removing the test material from the heating block without scratching its surface.
7 Sampling
Take a representative sample of the product to be tested as described in ISO 15528.
8 Procedure
The gel time determined by this method is not directly related to the time for a coating powder to cure in practical applications.
Carry out the test at (180 ± 1) °C unless otherwise specified or agreed between the interested parties.
Place the heating block (1) in a draught free environment. Raise the temperature of the heating block to the specified temperature and allow it to stabilize for at least 10 mm.
Check that the surface temperature of the heating block has reached the required temperature. A small
portion of suitable material (5.1) that melts at the required temperature may be used. NOTE A calibrated surface contact thermometer can also be used to verify the temperature in the depression.
By means of the measuring spoon transfer a test portion of 0,25 ml of the product into the depression in the heating block and, unless otherwise agreed or specified, start the timer (fA) immediately after all the powder has melted and commence stirring the material.
Stir the molten material in small circular movements with the stirrer (65). Upon an increase of viscosity, maintain the overall stirring action, then lift the stirring device every 2 s to 3 s to about 10 mm away from the molten material. When the threads thus formed become brittle, such that they break and can no longer be drawn from the molten material, stop the timer,
Record the time to the nearest 1 s. This is the gel time.
Immediately scrape the test material from the heating block, using the scraper (6) and taking care not
to damage the surface.
9 Precision
Precision data are currently not available.
10 Test report
The test report shall contain at least the following information:
a) all details necessary to identify the product tested;
b) a reference to this document, i.e. ISO 8130-6:2021;
c) the test temperature;ISO 8130-6 pdf download.
