Analysis of Efflorescence on Surfaces
Efflorescence can occur on materials such as glass, concrete or other materials. It arises from the migration of components to the surface of the material. Efflorescence is most common on plastics and is then referred to as “blooming”. Blooming in plastics is most often caused by incorrect dosage of formulation components, long storage under unfavorable climatic conditions, or the use of additives that are incompatible with the polymer or other additives.
The properties of a plastic can be changed in a targeted manner by adding additives (e.g. plasticizers, flame retardants or antioxidants). If the used additives fail, this leads to the loss of essential properties (e.g. UV stability) and, in the long run, often to the failure of the plastics. The damage patterns can be diverse: The material’s mechanical properties may change, e.g . by the material turning brittle. The appearance may also deteriorate. The material may turn yellowing, get a matt, rough or greasy surface or discolor. The surface effects are commonly examined in the Tascon laboratory. Of course, polymer processors have a great interest in understanding the damage that occurs, recognizing the cause and avoiding the problem in the future. Analytical methods such as ToF-SIMS, FT-IR or XPS (ESCA) can provide helpful information, as the following example of the analysis of blooming on plastic shows:
Blooming on polymers and plastics
Root cause analysis using ToF-SIMS
Anomalies on surfaces, such as discoloration, are often due to segregation, i.e. migration to the surface of the material components. Figure 1 shows a microscopic picture taken in our laboratory of a crystalline bloom on polypropylene (PP), which was characterized using ToF-SIMS. In order to clearly identify the structures that appear crystalline, the chemical composition of the surface was imaged, shown in figure 2. This ToF-SIMS image shows lithium stearate (in blue) on the surface of the PP base polymer (in red) and the stabilizer Ultranox 626 (in green) in the area of the crystalline structure. The crystalline needle structure of the additive material is clearly visible. An analysis with interferometric profilometry at the Tascon laboratory revealed that the bloom had a height of up to 8 µm.
Tascon - your partner for the study of blooming
If you are interested in further details, contact the experts at Tascon GmbH in the laboratory for the analysis and investigation of blooming or efflorescence on any surface.