Our research paper has been published:
https://doi.org/10.3390/polym13050820
Natural exposure sites develop deferent types of degradation in polymer samples. Yellowing indices shown below((a)-(d) are different types of poly carbonate samples exposed in several types of exposure sites and their YI developments) are sometimes similar in several exposure sites, but sometimes quite different. It is natural the differences have fluctuations, but we consider they can be comprehensively explained using some composition of simple environmental factors governing oxidative deterioration, such as temperature dependency, humidity dependency, and UV irradiation dependency.
Prediction models for polymer degradation frequently require very many fundamental information about chemical and physical properties of polymer samples in detail. Polymer degradation naturally develops depending on such properties, however, quite complex models using chemical properties should be avoided, because such properties contain confidential information for production companies. The users must take care of the degradation without such information.
Our proposing equation defines the temperature and humidity dependence in the Striny and Schelling model and Schwarzchild’s law factor for the contribution of UV irradiation. The fitting results with the Yellowing indices at the above figure are acceptable and successfully follow the fluctuations in accordance with actual environmental condition in each exposure site.
Additionally, cross-correlation between temperature and UV irradiation to analyses polymer degradation in natural exposure is subjected as shown below. We expect this method for other polymer degradation. More in detail are discussed on the full-text in this journal.
