Gas permeability (volumetric) according to DIN 53380-1 / DIN 53380-V
Universal testing method applicable to nearly all gases for the determination of gas transmission rate through plastic films depending on temperature and testing gas.
- Gas permeability in cm3/(m2*d*bar); Permeability coefficient (based on the thickness) in cm3*mm/(m2*d*bar).
- Declaration of cm3 at normal condition according to DIN 1343: volume of the gas at 273.15 K (0 °C) and 101325 Pa (1 atm).
- DIN 53380-2,
- DIN 53380-3,
- DIN 53380-4: Methods for the determination of gas permeability,
- ISO 1399:1983: Testing of rubber, determination of gas permeability, test with constant volume,
- ISO 2872:1977: Testing of rubber, determination of gas permeability, test with constant pressure.
The test sample is mounted in a permeation cell so as to form the barrier between two chambers.
One chamber is filled with the test gas until test pressure is reached. After reaching the desired temperature, the measurement is started.
The permeation gas displaces liquid out of a U-tube which is connected with the other chamber. The permeation coefficient is calculated as the slope of the displaced volume against time.
Range of the norm: approx. 3 to 20000 cm3/(m2*d*bar). Please contact us if you have differing requirements.
For testing please send us a sample of the approximate size of a sheet of paper (DIN A4, 210*297 mm).
For non flat specimens: please send after consulting with us.
The sample size is not regulated by the norm, 100 mm in diameter are proposed.
The specimens shall be uniform in thickness, representative for the material and free of pinholes and folds. On request we measure your sample thickness according to DIN 53370.
We recommend the measurement of three independent samples per test (minimum number not regulated in the standard). Our standard is to measure samples of 20 µm - 3 mm, others on request.
Required sample dimension: we perform the preparation of the samples for you.
For different test gases and type of samples we use different sized samples. If you want to conduct the cutting of the specimens, please contact us for the required dimensions.
For sensistive coating test sometimes it makes sense to prepare first the support followed by the coating. Please inform us if your samples tend to mechanical failure under applied pressure (of the test gas or the sealings).
Gases, vapours, solvent above boiling point.
Standard: O2, CH4, N2, Ar, He, H2, Cl2
Our permeation measurement cells are all-purpose because they are resistant to corrosion.
Please contact us for special applications. The testing method is normally limited to substances or mixtures which contain substances with strongly skewing permeation rates.
Scope of the standard: 23 °C +/- 1°C dry gas, ambient pressure on the feed side.
Mecadi's possible testing temperatures:
- Standard -50 °C up to +150 °C, other temperatures on request.
Temperature tolerance possible with Mecadi equipment: better than +/- 0.1 K (target: +/- 0.01 K)
Experience shows that +/- 1 K tolerance leads to permeation rate scattering up to 20 %.
Mecadi's possible testing pressures:
- Standard: until 100 bar, others on request.
Please contact us for information about special effects and requirements for the samples at high pressures.
Also possible are temperature profiles (nonisothermic measurements) for the determination of morphology changes and the influence of media and pressure to polymer properties. Based on this method, Mecadi offers further examination to determine gas solubilities (sorption and desorption), diffusion coefficients and the measurement of break through times through barriers.
Furthermore interactions between media and polymer can be investigated. So the predictions according resistance, physical and chemical reactions under process conditions can help in the selection process of materials.
For safety reasons, Mecadi does not conduct the detection of the the permeate with a mecury filled u-tube (scope of the standard) but an electronic pressure transducer (constant volume). Please contact us if you need standard conform detection.