The gravimetric measuring method
The gravimetric measurement method is a proven test method for determining the water/oil vapor permeability of almost any material such as plastic and polymer films, paper, cardboard and textiles, with or without a top layer. This method is based on the measurement of the amount of liquid permeating through the material sample, which is determined by weighing the sample structure. The material sample is firmly clamped in a so-called “cup” with a desiccant enclosure and exposed to a defined test climate. This allows precise values for water vapor permeability or the permeation coefficient (P) to be determined.
Open test containers (cups)
The advantages of our service
Our gravimetric measuring method offers a number of advantages for your applications:
- High accuracy: Thanks to our high-precision weighing technology, we achieve reliable results that enable an exact assessment of water vapor permeability.
- Versatility: We measure a wide range of materials, including plastic films, textiles and paper, both coated and uncoated.
- Standard-compliant evaluation: We are guided by international standards such as DIN 53122-1, ISO 2528:1995 and ASTM E-96 to guarantee you a high degree of standardization and reproducibility.
- Individual adaptations: We offer flexible test conditions and can respond to your specific requirements, such as testing under special climatic conditions or temperature profiles.
Detection limits and recommendations
The detection limit of the gravimetric measurement method is in the range of 1 to 200 g/m²d, as suggested in the standard. Depending on the nature of the sample and the sample thickness, however, significantly lower permeation rates of up to 0.1 g/m²d can also be recorded. The exact detection limit depends on the type of sample and the specific measurement conditions. Our expertise enables us to carry out precise measurements even for unconventional materials.
Test media
The standard test medium is water. Other test media can also be used on request if required for your specific application.
Test conditions
The standards recommend various test climate conditions for measuring water vapor permeability. These include:
- A: 23 °C, 90 % relative humidity
- B: 38 °C, 90 % relative humidity
- C: 25 °C, 75 % relative humidity
- D: 23 °C, 85 % relative humidity
- E: 20 °C, 85 % relative humidity
We also offer measurements under special climatic conditions on request. Special effects and requirements for the samples can also be taken into account, as well as non-isothermal measurements in which temperature profiles are determined to investigate morphological changes and how they are influenced by temperature and humidity.
Get in touch with us
Would you like to find out more about our gravimetric measuring method and its application or do you have specific requirements that we can investigate for you? Get in touch with us! Our team of experts are on hand to answer your questions and offer customized solutions for your testing requirements.
We look forward to hearing from you!
Related standards:
DIN 53122-1 / DIN 53122-A
ISO 2528:1995
ASTM E-96
By the way: You can find a complete list of our test methods and services here: https://www.mecadi.com/de/permeationsmessungen/ (more on request)
