title: Paving the Thermal Highway with Self-Organized Nanocrystals in Transparent Polymer Composites.
abstract: Phonon transfer is greatly scattered in traditional polymer composites due to the unpaired phonon frequency at the polymer/filler interface. A key innovation of this work is to build continuous crystal network by self-organization and utilize it as "thermal highway" that circumvents the long-existing interfacial thermal barrier issue in traditional composites. By tuning the molecular diffusion rate of dicarboxylic acids (oxalic acid, malonic acid, and succinic acid), different crystal structures including skeletal, dendrite, diffusion-limited aggregates, and spherulite were synthesized in PVA film. These continuous crystal structures benefit the efficient phonon transfer in the composites with minimized interfacial scattering and lead to a significant thermal conductivity enhancement of up to 180% compared to that of pure polymer. Moreover, the transparent feature of these composite films provides additional benefits in display applications. The post heat treatment effect on the thermal conductivity of the composite films shows a time-dependent behavior. These uniquely structured polymer/crystal composites are expected to generate significant impacts in thermal management applications.
authors.affiliation: Intelligent Composites Laboratory, Department of Chemical and Biomolecular Engineering, The University of Akron , Akron, Ohio 44325, United States.|Division of Machine Elements, Luleå University of Technology , Luleå 97187, Sweden.
authors.forename: Liwen
authors.initials: L
authors.lastname: Mu
authors.affiliation: Intelligent Composites Laboratory, Department of Chemical and Biomolecular Engineering, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Tuo
authors.initials: T
authors.lastname: Ji
authors.affiliation: Intelligent Composites Laboratory, Department of Chemical and Biomolecular Engineering, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Long
authors.initials: L
authors.lastname: Chen
authors.affiliation: Intelligent Composites Laboratory, Department of Chemical and Biomolecular Engineering, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Nitin
authors.initials: N
authors.lastname: Mehra
authors.affiliation: Division of Machine Elements, Luleå University of Technology , Luleå 97187, Sweden.
authors.forename: Yijun
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Intelligent Composites Laboratory, Department of Chemical and Biomolecular Engineering, The University of Akron , Akron, Ohio 44325, United States.
authors.forename: Jiahua
authors.initials: J
authors.lastname: Zhu
keywords: crystal network; phonon; polymer composites; thermal conductivity; transparent