https://sam.ensam.eu:443 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Sat, 18 Apr 2026 23:16:58 GMT 2026-04-18T23:16:58Z http://hdl.handle.net/10985/25864 Estimating network lifetime of AUN in photo‐aging by kinetic modeling and “degelation” model ISHIDA, Takato; RICHAUD, Emmanuel; HAGIHARA, Hideaki; KITAGAKI, Ryoma The study develops an oxidative kinetic model of acrylic‐urethane network during photo‐aging. The kinetic model can track chemical reaction dynamics well and also enables to estimate the network lifetime by counting scission/crosslinking events. Estimated network lifetime is semiquantitively coincided with the one derived from different statistical approach. Thu, 01 Aug 2024 00:00:00 GMT http://hdl.handle.net/10985/25864 2024-08-01T00:00:00Z ISHIDA, Takato RICHAUD, Emmanuel HAGIHARA, Hideaki KITAGAKI, Ryoma The study develops an oxidative kinetic model of acrylic‐urethane network during photo‐aging. The kinetic model can track chemical reaction dynamics well and also enables to estimate the network lifetime by counting scission/crosslinking events. Estimated network lifetime is semiquantitively coincided with the one derived from different statistical approach. http://hdl.handle.net/10985/22275 Thermal aging of acrylic-urethane network: Kinetic modeling and end-of-life criteria combined with mechanical properties ISHIDA, Takato; GERVAIS, Matthieu; GAUDY, Alain; KITAGAKI, Ryoma; HAGIHARA, Hideaki; ELAKNESWARAN, Yogarajah; RICHAUD, Emmanuel This study addresses the multiscale analysis of acrylic urethane networks (AUN). To establish the kinetic model for predicting AUN oxidation, this study considered the pure thermal oxidation of AUN at 160, 180, and 200 °C. Chemical changes were monitored using infrared spectroscopy. These indicated the presence of an imide, presumably generated from the oxidation of CH2 at the α-position of nitrogen. On the macromolecular and macroscopic scales, oxidation was shown to induce predominant crosslinking, leading to a drop in toughness (i.e., embrittlement). The novel kinetic model of AUN thermal aging was developed from a mechanistic scheme previously established for polyamide 11, by adding some extra paths of thermolytic alkyl radical formation, oxidative Nsingle bondH bonds decomposition and coupling of aminyl radicals. Sat, 01 Jan 2022 00:00:00 GMT http://hdl.handle.net/10985/22275 2022-01-01T00:00:00Z ISHIDA, Takato GERVAIS, Matthieu GAUDY, Alain KITAGAKI, Ryoma HAGIHARA, Hideaki ELAKNESWARAN, Yogarajah RICHAUD, Emmanuel This study addresses the multiscale analysis of acrylic urethane networks (AUN). To establish the kinetic model for predicting AUN oxidation, this study considered the pure thermal oxidation of AUN at 160, 180, and 200 °C. Chemical changes were monitored using infrared spectroscopy. These indicated the presence of an imide, presumably generated from the oxidation of CH2 at the α-position of nitrogen. On the macromolecular and macroscopic scales, oxidation was shown to induce predominant crosslinking, leading to a drop in toughness (i.e., embrittlement). The novel kinetic model of AUN thermal aging was developed from a mechanistic scheme previously established for polyamide 11, by adding some extra paths of thermolytic alkyl radical formation, oxidative Nsingle bondH bonds decomposition and coupling of aminyl radicals.