Abstract
The radial local dynamics in poly(1,4-trans-butadiene) melts is studied using molecular dynamics simulations. In this work, the hopping peak is observed in the Van Hove space-time correlation function Gs(r,t) for the first time in polymeric systems. The hopping motion, observed only for methine hydrogen, is also identified in the mean-square displacement 〈Δr2(t)〉 and the intermediate scattering function Fs(k,t) through the relative dynamics of the hopping methine hydrogen and the nonhopping methylene hydrogen. The hopping motion is found to cause an unusual broadening of the dispersion width in the dynamic structure factor Sinc(k,ω). Active free volume is proposed in terms of Gs(r,t) at a short time, which offers a consistency to the relationship between free volume and local dynamics. Fast counterrotation at a pair of CH–CH2 bonds across a CH=CH bond is found responsible for the hopping peak in this polymer, and a new hopping criterion modified for polymeric liquids is proposed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
