In this study, the influence of artificial aging on the mechanical and thermal properties and VOC emissions of medical grade polypropylene (PP) is investigated. For the investigations, tensile test specimens were produced on an injection molding machine. To test the long-term stability of the materials, the ASTM 1980 guideline was adopted at the temperatures of 65 °C, 90 °C and 120 °C. The thermal, mechanical and emission properties were tested using differential scanning calorimetry (DSC), tensile tests and GC-MS analysis before and after artificial aging. The results of the tensile tests show a decrease in elongation at break with increasing temperature and storage time. Similarly, the results of the DSC measurements show an increase in melting enthalpy, which indicates post-crystallization in the material. The GC-MS results show that the emissions due to artificial aging decrease with increasing temperature and storage time, so that the emissions of the samples stored at 120 °C are almost zero.
Rüppel et al. (Wed,) studied this question.