Dimensional crossover of heat conduction in amorphous polyimide nanofibers. Issue 4 (9th January 2018)

• Record Type: Journal Article
• Authors: Dong, Lan; Xi, Qing; Chen, Dongsheng; Guo, Jie; Nakayama, Tsuneyoshi; Li, Yunyun; Liang, Ziqi; Zhou, Jun; Xu, Xiangfan; Li, Baowen
• Is Part Of: National science review. Volume 5:Issue 4(2018)
• Page Start: 500
• Page End: 506
• Publication Date: 2018-01-09
• Subjects: dimensional crossover -- thermal conductivity -- nanofiber; Science -- Periodicals; 505
• DOI: 10.1093/nsr/nwy004
• Languages: English
• ISSNs: 2095-5138

Abstract

ABSTRACT: The mechanism of thermal conductivity in amorphous polymers, especially polymer fibers, is unclear in comparison with that in inorganic materials. Here, we report the observation of a crossover of heat conduction behavior from three dimensions to quasi-one dimension in polyimide 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 on the upper limit of thermal conductivity of amorphous polymers in the quasi-1D limit.