Effect of Crystallinity on Polymer Chain Compression in Polyethylene Dynamically Loaded with <em>In-Situ</em> X-Ray Diffraction

Polyethylene (PE) is a polymer widely used in commercial applications, where the properties of PE can be altered based on the molecular conformation. In this study, shock compression experiments with in-situ x-ray diffraction were conducted on two conformations of PE– low density polyethylene (LDPE) and ultra-high molecular weight polyethylene (UHMWPE). Encouragingly, X-ray diffraction patterns were easily observed in LDPE, which is only 25% crystalline. In agreement with a previous study on HDPE, LDPE exhibited a phase transition at 7.7 GPa. Lower pressure experiments on UHMWPE and LDPE exhibited polymer chain compression, but no occurrence of a phase transition.. Authors: Jordan, Jennifer Lynn [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000245965872); Huber, Rachel Colleen [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000158750208); Dattelbaum, Dana Mcgraw [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000294125917); Bartram, Brian Douglas [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]; Gibson, Lloyd Lee [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]. DOE Contract: 89233218CNA000001; AC02-06CH11357; NA0003957. Subjects: 36 MATERIALS SCIENCE