Related Experiment Video
Updated: Jun 26, 2026

Fabrication of Large-area Free-standing Ultrathin Polymer Films
Published on: June 3, 2015
Optimization of the Thermally Conductive Low-k Polymer Dielectrics Based on Multisource Free-Volume Effects
Weidi Xu1, Ziyang Wang1, Hong Cao1
1College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, China.
Abstract:
Polymers/polymer matrix composites possessing low dielectric constants (low-k polymer dielectrics) contribute to the advance of electronics, for instance, microprocessor chips, mobile phone antennas, and data communication terminals. However, the intrinsic long-chain structural characteristic results in poor thermal conductivities, which draw heat accumulation and undermine the outstanding low-k performance of polymers. Herein, multisource free-volume effects that combine two novel kinds of extra free volume with the known in-cage free volume of polyhedral oligomeric silsesquioxanes (POSSs) are discussed to reduce the capacity for dielectric constant reduction. The multisource free-volume effects of POSSs are associated with the thermal conductive network formed by the hexagonal boron nitride (BN) in the polymer matrix. The results show a decent balance between low-k performance (dielectric constant is 2.08 at 1 MHz and 1.98 at 10 GHz) and thermal conductivity (0.555 W m-1 K-1, 4.91 times the matrix). The results provide a new idea to maximize the free-volume effects of POSSs to optimize dielectric properties together with other desired performances for the dielectrics.
Related Concept Videos
Electrophilic Addition of HX to 1,3-Butadiene: Thermodynamic vs Kinetic Control
Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Complexation Equilibria: Overview
The equilibrium constant of the complexation reaction is represented as the formation constant...
Complexation Equilibria: The Chelate Effect
Extraction: Advanced Methods

