Technical Paper
Identification of TPO blooming products after environmental exposure by Fourier-transform infrared (FTIR) & gas chromatography coupled to mass spectrometry (GC-MS)
2018-09-03
2018-36-0063
A visible exudation of additives on Thermoplastic Polyolefin (TPO) compounds part surface called as blooming is always a challenge to Polypropylene (PP) compounders due the complex chemistry involved and reactions occurred under specific environmental conditions. Slip agents, light stabilizers, antioxidants, plasticizers, nucleants, pigments and fillers should keep certain stability under severe humidity, temperature and ultra violet (UV) light during an environmental aging. As expected, some of these additives should migrate to part surface to enable their functionality such as anti-scratch and light stabilizers. A faster migration leads to a blooming issue that promotes changes in gloss, tactual and appearance. An alternative to reduce the high migratory velocity of slip agents is to switch to high molecular weight as polysiloxane. The result expected with this change is to reduce blooming and enhancement of anti-scratch effect.