Mandrel degradation model of combined fast and slow processes  

作　　者：Yu Zhu Zheng Liu Famin Yu Qiang Chen Wei Feng Zhanwen Zhang Zhigang Wang 

机构地区：[1]Institute of Atomic and Molecular Physics,Jilin University,Changchun 130012,China [2]Laser Fusion Research Center,China Academy of Engineering Physics,Mianyang 621900,China

出　　处：《High Power Laser Science and Engineering》2021年第1期1-7,共7页高功率激光科学与工程（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.11974136 and 11674123)。

摘　　要：In this paper, we report the study of degradation for a kind of ideal mandrel material called poly-α-methylstyrene based on theoretical and experimental methods. First-principles calculations reveal two types of process: depolymerization and hydrogen-transfer-induced chain scission. The energy barrier for the former(0.68–0.82 eV) is smaller than that for most of the latter(1.39–4.23 eV). More importantly, reaction rates suggest that the former is fast whereas the latter is mostly slow, which can result in a difference of 5–31 orders of magnitude at 550 K. Furthermore, a thermogravimetric experiment shows that the activation energy of 2.53 eV for degradation is between those of fast and slow processes,corresponding to the theoretical average value of multiple reaction paths. Thus, a mandrel degradation model combining fast and slow processes is established at the atomic level. Our work provides a direction for research into the key technology of target fabrication in inertial confinement fusion.

关 键 词：atomic level DEGRADATION first principles mandrel material thermogravimetric experimenth 

分 类 号：TQ317[化学工程—高聚物工业]