English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We calculate the thermal conductivity (\k{appa}) of both bulk crystalline andsingle-chain polyethylene (PE) using the first-principles-based anharmoniclattice dynamics. Despite its low \k{appa} in amorphous state, the predictedbulk crystal has high axial \k{appa} (237 W/m-K) at room temperature. The muchlower measured \k{appa} is attributed to the small size of nanocrystallites(~10 nm) in synthesized semi-crystalline PE. For the 1-D chain, the predicted\k{appa} is much larger and yet finite (1400 W/m-K at room temperature). Thereduction of scattering phase space caused by the diminished interchain van derWaals interactions explains this larger \k{appa}. It is also found that thetransverse phonon branches with quadratic dispersion make minor contribution tothis, due to their vanishing group velocity in the long-wavelength limit.Moreover, the low-frequency bending and twisting phonon modes are stronglycoupled and dominate anharmonic phonon scatterings, leading to the finite\k{appa}. The predicted high \k{appa} of bulk and chain PE crystals enablepolymer usage in thermal management and the above phonon scatterings provideguide for their nano-designs.

Further improvement of lattice thermal conductivity from bulk  crystalline to 1-D-chain polyethylene: A high-yet-finite thermal conductivity  using first-principles calculation