Chemical material resistances

Description of chemical material resistance
Chemical material resistance describes how well a material resists various chemicals without deforming or decomposing. It is crucial for selecting the right material for applications that require resistance to certain chemicals such as acids, alkalis, solvents or oils. Unlike corrosion, there is no material abrasion. *
Classification of chemical material resistance
Chemical material resistance is classified using the designations ‘chemically resistant’, ‘conditionally resistant’ and ‘chemically non-resistant’.
- Chemically resistant: Despite prolonged contact with the chemical substance being tested, the plastic retains its characteristic mechanical, physical and chemical properties without undergoing any changes. In practice, this never occurs so clearly. Therefore, a material is also considered chemically resistant if it undergoes a very slow change.
- Conditionally chemically resistant: The plastic retains its characteristic properties for a limited period of time. However, this is acceptable for the application or is within the existing conditions of use.
- Chemically unstable: The plastic loses its characteristic properties within a very short time or faster than required for the application.
When a plastic comes into contact with chemicals to which it is unstable, the material swells or softens. The molecules of the chemical diffuse into the plastic and break down the weak bonds between the polymer chains.
In some cases, this leads to the formation of microcracks in the material. These enlarge under higher mechanical stress and eventually lead to macroscopic cracks. This phenomenon is known as stress cracking. Since diffusion is temperature-dependent, the chemical resistance of plastics decreases with increasing temperature. *
Tables on chemical material resistance
In consultation with our raw material suppliers, we have compiled the following tables on the chemical material resistance of plastics and plastic types. The information is based on tests carried out in a laboratory environment. We therefore ask you to use these values only as a guide and, in case of doubt, always carry out your own tests.
We exclude any warranty and liability.
Chemical material resistances of different plastics
Chemical material resistances of different plastic types
*) Source: Wikipedia