Fraunhofer Institute for Structural Durability and System Reliability LBFSorption of gas in plastics for applications i such as packaging, electronics, and hydrogen storage is an important property. Gas sorption refers to the process by which a gas is absorbed into a solid. In plastics, gas absorption usually occurs due to interactions between the gas molecules and the polymer chains. These interactions can be based on various interactions, such as van der Waals forces (Debye or London type), or chemical reactions between the polymer and hydrogen molecules.
Gas absorption in plastics can have both positive and negative effects. On the positive side, for example, there is controlled gas permeability in food packaging or medical technology. Negative effects include changes in mechanical properties or optical transparency. In addition, certain gases, such as oxygen, can contribute to the degradation of plastics and thus reduce the service life of the material. Sorption is particularly important in the field of hydrogen storage.
A gas sorption balance is available at Fraunhofer LBF for gas sorption measurements, which enables measurements with various gases in a temperature range from 20 °C to 150 °C and a pressure range from 0 bar to 350 bar. The measured values and the material properties calculated from this help to characterize plastics and elastomers regarding their sorption properties and serve as input parameters for mathematical models and simulations.
