AA << report the observation of a crossover of heat conduction behavior from three dimensions (3D) to quasi-one dimension (1D) in Polyimide(PI) nanofibers at a given temperature. A theoretical model based on the random walk theory has been proposed to quantitatively describe the interplay between the inter-chain hopping and the intra-chain hopping in nanofibers. This model explains well the diameter dependence of thermal conductivity and also speculates the upper limit of thermal conductivity of amorphous polymers in the quasi-1D limit. >>
Lan Dong, Qing Xi, et al. Dimensional crossover of heat conduction in amorphous Polyimide nanofibers. National Science Review. nwy004. doi: 10.1093/nsr/nwy004. Jan 09, 2018.
<< The intrinsic structure of amorphous polymers is highly disordered with long, entangled molecular chains >>
Science China Press. "Random walk" of heat carriers in amorphous polymers. Mar 01, 2018.