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Goto T, Abe H. Substituent Effects on Thermal and Mechanical Properties of Resorcinol‐Based Semiaromatic Polyesters. MACROMOL CHEM PHYS 2022. [DOI: 10.1002/macp.202100355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Tatsuya Goto
- Bioplastic Research Team RIKEN Center for Sustainable Resource Science 2‐1 Hirosawa, Wako Saitama 351–0198 Japan
| | - Hideki Abe
- Bioplastic Research Team RIKEN Center for Sustainable Resource Science 2‐1 Hirosawa, Wako Saitama 351–0198 Japan
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Huang X, Orimoto Y, Aoki Y. Theoretical Analysis of Properties of Ground and Excited States for Photodissociation of the C-O Bond in Polycarbonates. J Phys Chem A 2021; 125:6662-6673. [PMID: 34319114 DOI: 10.1021/acs.jpca.1c03074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quantum chemical calculations were carried out to investigate the properties of the ground state (GS) and the excited state (ES) of bisphenol-A polycarbonate (PC) with bisphenol-A hydrogen carbonate (BPAHC) as a model compound. Time-dependent density functional theory (TDDFT) was used to obtain the absorption spectrum and the corresponding transition natures of BPAHC. Furthermore, the ESs related to the transitions of the carbonate group and neighboring phenyl ring were optimized employing the TDDFT method for photodegradation. Our results showed that the carbonate group is broken at an ES with relatively high energy, which has a significant C-O bond cleavage within the carbonate group compared to that of GS geometry. The carbonate group C-O bond cleavage is caused by two reasons. One is the transition from the O lone pair to the carbonate π anti-bonding which is commonly known, and the other one is the transition from the O lone pair to the phenyl group (adjacent to the carbonate group) π anti-bonding that is newly proposed.
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Affiliation(s)
- Xiao Huang
- Department of Material Sciences, Faculty of Engineering Sciences, Kyushu University, 6-1 Kasuga-Park, Fukuoka 816-8580, Japan
| | - Yuuichi Orimoto
- Department of Material Sciences, Faculty of Engineering Sciences, Kyushu University, 6-1 Kasuga-Park, Fukuoka 816-8580, Japan
| | - Yuriko Aoki
- Department of Material Sciences, Faculty of Engineering Sciences, Kyushu University, 6-1 Kasuga-Park, Fukuoka 816-8580, Japan.,Japan Science and Technology Agency, CREST, 4-1-8 Hon-chou, Kawaguchi, Saitama 332-0012, Japan
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Ascione L, Mistretta MC, Pedeferri M, La Mantia FP. Effect of environmental conditions on the durability of polycarbonate for the protection of cultural heritage sites. J Appl Biomater Funct Mater 2019; 17:2280800019881626. [PMID: 31847671 DOI: 10.1177/2280800019881626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Polycarbonate is a good material for covering and protecting cultural heritage sites because of its durability, mechanical properties, and transparency. However, polycarbonate degrades under environmental weathering with a significant decrease of physical and mechanical properties and loss of transparency. In this work, the contemporary presence of ultraviolet irradiation and different temperature and moisture conditions have been taken into account to study the environmental degradation of this polymer with regard to its mechanical and optical properties. The photo-oxidation reactions cause a decrease in the molecular weight and the formation of many oxygenated species. The hydrolytic scission, instead, gives rise to a remarkable reduction in the molecular weight. These two different degradation mechanisms do not seem interconnected because at the lowest degradation temperature and high humidity levels, the reduction of the molecular weight is more pronounced than that observed at the highest temperature but at a lower humidity level. Transparency decreases with the degradative processes, but even after severe degradation the loss of transparency is only about 10%. The yellowness index increases during the first stages of degradation, which has been attributed to the fast formation of carbonyl groups due to photo-oxidation.
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Affiliation(s)
- Laura Ascione
- Department of Engineering, University of Palermo, Palermo, Italy.,INSTM, National Interuniversity Consortium of Materials Science and Technology, UdR Palermo, Palermo, Italy
| | - Maria Chiara Mistretta
- Department of Engineering, University of Palermo, Palermo, Italy.,INSTM, National Interuniversity Consortium of Materials Science and Technology, UdR Palermo, Palermo, Italy
| | - MariaPia Pedeferri
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Milan, Italy.,INSTM, National Interuniversity Consortium of Materials Science and Technology, UdR Politecnico di Milano, Italy
| | - Francesco Paolo La Mantia
- Department of Engineering, University of Palermo, Palermo, Italy.,INSTM, National Interuniversity Consortium of Materials Science and Technology, UdR Palermo, Palermo, Italy
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Xie F, Zhang T, Bryant P, Kurusingal V, Colwell JM, Laycock B. Degradation and stabilization of polyurethane elastomers. Prog Polym Sci 2019. [DOI: 10.1016/j.progpolymsci.2018.12.003] [Citation(s) in RCA: 143] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Singh R, Shahi S, Geetanjali. Chemical Degradation of Poly(bisphenol A carbonate) Waste Materials: A Review. ChemistrySelect 2018. [DOI: 10.1002/slct.201802577] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Ram Singh
- Department of Applied chemistryDelhi Technological University Delhi-110042 India
| | - Surybala Shahi
- Department of Applied chemistryDelhi Technological University Delhi-110042 India
| | - Geetanjali
- Department of ChemistryKirori Mal CollegeUniversity of Delhi Delhi – 110 007 India
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Wang Y, Wang X, Li T, Ma P, Zhang S, Du M, Dong W, Xie Y, Chen M. Effects of Melanin on Optical Behavior of Polymer: From Natural Pigment to Materials Applications. ACS APPLIED MATERIALS & INTERFACES 2018; 10:13100-13106. [PMID: 29577714 DOI: 10.1021/acsami.8b02658] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Melanin is a kind of ubiquitous natural pigment, which serves a variety of protective functions in many organisms. In the present study, natural melanin and synthetic melanin nanoparticles (NPs) were systematically investigated for its potential application in polymeric optical materials. A significant short-wavelength shielding and high visible light transparency polymer nanocomposite was easily obtained via tuning the melanin particle size. In particular, the nanocomposite film with melanin NPs (diameter ≈ 15 nm) loading even as low as 1 wt % blocks most ultraviolet light below 340 nm and still keeps high visible light transparency (83%) in the visible spectrum. More importantly, because of the excellent photoprotection and radical scavenging capabilities of melanin, the resulting polymer nanocomposite exhibits outstanding photostability. In effect, such fantastic melanin NPs is promising for applications in various optical materials.
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Affiliation(s)
- Yang Wang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
| | - Xuefei Wang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
| | - Ting Li
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
| | - Piming Ma
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
| | - Shengwen Zhang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
| | - Mingliang Du
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
| | - Weifu Dong
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
| | - Yi Xie
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
| | - Mingqing Chen
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering , Jiangnan University , 1800 Lihu Road , Wuxi 214122 , China
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Andrady AL, Hamid H, Torikai A. Effects of solar UV and climate change on materials. Photochem Photobiol Sci 2011; 10:292-300. [DOI: 10.1039/c0pp90038a] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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