Mathematical Modeling of Outdoor Natural Weathering of Polycarbonate: Regional Characteristics of Degradation Behaviors
Many natural exposure sites have been developed to ensure the reliability of materials intended for outdoor use. However, the effects of local climate on aging have not been completely understood. This study aimed to elucidate the regional characteristics of natural aging. Non-stabilized and stabili...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-03-01
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| Series: | Polymers |
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| Online Access: | https://www.mdpi.com/2073-4360/13/5/820 |
| _version_ | 1797412545520205824 |
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| author | Takato Ishida Ryoma Kitagaki |
| author_facet | Takato Ishida Ryoma Kitagaki |
| author_sort | Takato Ishida |
| collection | DOAJ |
| description | Many natural exposure sites have been developed to ensure the reliability of materials intended for outdoor use. However, the effects of local climate on aging have not been completely understood. This study aimed to elucidate the regional characteristics of natural aging. Non-stabilized and stabilized polycarbonates were monitored in terms of their appearance (yellowing and loss of gloss) during natural weathering at five exposure sites (Tokyo, Kagoshima, Okinawa, Florida, and Arizona) in conjunction with climate fluctuation for up to 24 months. Three approaches were employed to characterize the natural aging behaviors: (i) modeling the rate function of degradation, (ii) evaluating the contribution ratio of individual degradational factors, and (iii) estimating the “synchronicity” by cross-correlation analysis with the climate dataset. The aging rates were the highest in Arizona and lowest in Kagoshima among the five exposure sites. First, prediction curves were constructed from the degradation rate function (variables: UV irradiation, temperature, and humidity), and these curves were found to agree well with the measured aging behaviors. Second, the exposure data in Arizona demonstrated strong temperature dependence, while those in Okinawa and Florida had stronger dependence on UV irradiation compared to other sites. Lastly, the synchronicity between UV irradiation and temperature was the highest in Arizona and lowest in Kagoshima, which can explain the significantly faster deterioration in Arizona and the slow deterioration in Kagoshima. |
| first_indexed | 2024-03-09T05:03:39Z |
| format | Article |
| id | doaj.art-0db1a66f909646acba62c3ac60987a88 |
| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-03-09T05:03:39Z |
| publishDate | 2021-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Polymers |
| spelling | doaj.art-0db1a66f909646acba62c3ac60987a882023-12-03T12:56:20ZengMDPI AGPolymers2073-43602021-03-0113582010.3390/polym13050820Mathematical Modeling of Outdoor Natural Weathering of Polycarbonate: Regional Characteristics of Degradation BehaviorsTakato Ishida0Ryoma Kitagaki1Graduate School of Engineering, Hokkaido University, Nishi-8-chome, Kita-13-jyo, Kita-ku, Sapporo-shi, Hokkaido 060-8628, JapanGraduate School of Engineering, Hokkaido University, Nishi-8-chome, Kita-13-jyo, Kita-ku, Sapporo-shi, Hokkaido 060-8628, JapanMany natural exposure sites have been developed to ensure the reliability of materials intended for outdoor use. However, the effects of local climate on aging have not been completely understood. This study aimed to elucidate the regional characteristics of natural aging. Non-stabilized and stabilized polycarbonates were monitored in terms of their appearance (yellowing and loss of gloss) during natural weathering at five exposure sites (Tokyo, Kagoshima, Okinawa, Florida, and Arizona) in conjunction with climate fluctuation for up to 24 months. Three approaches were employed to characterize the natural aging behaviors: (i) modeling the rate function of degradation, (ii) evaluating the contribution ratio of individual degradational factors, and (iii) estimating the “synchronicity” by cross-correlation analysis with the climate dataset. The aging rates were the highest in Arizona and lowest in Kagoshima among the five exposure sites. First, prediction curves were constructed from the degradation rate function (variables: UV irradiation, temperature, and humidity), and these curves were found to agree well with the measured aging behaviors. Second, the exposure data in Arizona demonstrated strong temperature dependence, while those in Okinawa and Florida had stronger dependence on UV irradiation compared to other sites. Lastly, the synchronicity between UV irradiation and temperature was the highest in Arizona and lowest in Kagoshima, which can explain the significantly faster deterioration in Arizona and the slow deterioration in Kagoshima.https://www.mdpi.com/2073-4360/13/5/820polycarbonateoutdoor agingdegradation rateclimate characteristics |
| spellingShingle | Takato Ishida Ryoma Kitagaki Mathematical Modeling of Outdoor Natural Weathering of Polycarbonate: Regional Characteristics of Degradation Behaviors Polymers polycarbonate outdoor aging degradation rate climate characteristics |
| title | Mathematical Modeling of Outdoor Natural Weathering of Polycarbonate: Regional Characteristics of Degradation Behaviors |
| title_full | Mathematical Modeling of Outdoor Natural Weathering of Polycarbonate: Regional Characteristics of Degradation Behaviors |
| title_fullStr | Mathematical Modeling of Outdoor Natural Weathering of Polycarbonate: Regional Characteristics of Degradation Behaviors |
| title_full_unstemmed | Mathematical Modeling of Outdoor Natural Weathering of Polycarbonate: Regional Characteristics of Degradation Behaviors |
| title_short | Mathematical Modeling of Outdoor Natural Weathering of Polycarbonate: Regional Characteristics of Degradation Behaviors |
| title_sort | mathematical modeling of outdoor natural weathering of polycarbonate regional characteristics of degradation behaviors |
| topic | polycarbonate outdoor aging degradation rate climate characteristics |
| url | https://www.mdpi.com/2073-4360/13/5/820 |
| work_keys_str_mv | AT takatoishida mathematicalmodelingofoutdoornaturalweatheringofpolycarbonateregionalcharacteristicsofdegradationbehaviors AT ryomakitagaki mathematicalmodelingofoutdoornaturalweatheringofpolycarbonateregionalcharacteristicsofdegradationbehaviors |