We apply united-atom (UA) nonequilibrium molecular dynamics simulations to predict the thermal conductivity for amorphous polyethylene at room temperature with chain length (CL) increasing from 4 to 1260. The thermal conductivity is determined by the competition of the two mechanisms: (1) The collision among the UA beads and (2) the phonon vibration. The collision mechanism mainly dominates CL 7, while the phonon vibration mechanism mainly determines CL 140. The competition between the two mechanisms determines 12 CL 140. In particular, the thermal conductivity for 8 CL 11 cannot be obtained accurately due to the aggregation of the beads.
ASJC Scopus subject areas
- Physics and Astronomy(all)