Related Experiment Video
Updated: Feb 18, 2026

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Phonon coupling and transport in individual polyethylene chains: a comparison study with the bulk crystal
Xinjiang Wang1, Massoud Kaviany, Baoling Huang
1Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong. mebhuang@ust.hk.
Abstract:
Using the first-principles-based anharmonic lattice dynamics, we calculate the thermal conductivities (κ) of both bulk and single-chain polyethylene (PE) and characterize the mode-wise phonon transport and scattering channels. A significantly higher room-temperature axial thermal conductivity in single-chain PE (1400 W m-1 K-1) is observed compared to bulk PE crystals (237 W m-1 K-1). The reduction of scattering phase space caused by the diminished inter-chain van der Waals interactions explains the much larger κ in single-chain PE. Different from many previous studies, the thermal conductivity of single-chain PE is predicted to converge at a chain length of ∼1 mm at 300 K. The convergence is explained by the indirect thermal resistance from momentum-conserving scatterings of long-wavelength phonons. It is also found that longitudinal phonon modes dominate the thermal transport in PE chains, while transverse phonon branches with quadratic dispersions contribute little to κ due to their vanishing group velocities and limited lifetimes in the long wavelength limit. The predicted high κ of bulk crystalline and single-chain PE show great potential for use of polymers in thermal management, and the unveiled phonon transport mechanisms offer guides for their molecule-level design.
More Related Videos
Related Concept Videos
Polymer Classification: Crystallinity
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
¹H NMR: Long-Range Coupling
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
Polymer Classification: Architecture
Spin–Spin Coupling: One-Bond Coupling
IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
According to Hooke's law, the vibrational frequency is directly proportional to...
Spin–Spin Coupling Constant: Overview
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...

