|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Dynamic Behavior of Materials VIII
||Anisotropic Shock Response of Poly (P-Phenylene Terephthalamide) (PPTA) and its Implications for Aramid-based Fibers Performance
||Paulo Branicio, Subodh C. Tiwari, Kohei Shimamura, Fuyuki Shimojo, Aiichiro Nakano, Rajiv K. Kalia, Priya Vashishta
|On-Site Speaker (Planned)
Ab initio multi-scale shock technique molecular dynamics simulations are used to investigate the dynamic response of poly (p-phenylene terephthalamide) (PPTA) crystals to strong shock loading. The shock Hugoniot at all regimes from elastic to polymer decomposition are considered. The anisotropic response for shocks perpendicular to the crystal symmetry axis (fiber axis) include stress release mechanisms combining structural phase transformation and generation of paracrystallinity. SPT is triggered by  shock-induced coplanarity of amide and phenylene groups and results in rearrangement of PPTA sheet stacking. Paracrystallinity is generated by  shock-induced scission of hydrogen bonds, disruption of chain sheets, and trans-cis polymer conformation change. The former atomic mechanism preserves crystalline order and PPTA properties while the latter strongly affects the crystal strength. These results shine light on the shock release mechanisms and are expected to assist the design of novel aramid fibers with enhanced performance.
||Planned: Supplemental Proceedings volume