학술논문

High Intrinsic Thermal Conductivity of Polythiophene by Reducing Steric Hindrance and Enhancing p‐π Conjugation.
Document Type
Article
Source
Macromolecular Chemistry & Physics. May2021, Vol. 222 Issue 10, p1-8. 8p.
Subject
*THERMAL conductivity
*STERIC hindrance
*POLYTHIOPHENES
*YOUNG'S modulus
*MOLECULAR dynamics
Language
ISSN
1022-1352
Abstract
A series of copolymers of poly3‐alkylthiophene (PTm) with different side chain lengths and copolymers of 3‐butylthiophene and 3‐butoxythiophene (PTDx) with different ratios are synthesized by oxidative polymerization. As the length of the side chain decreases, WAXD patterns of PTm show an increase in crystallinity. An increment of 50% in thermal conductivity is observed and the maximum thermal conductivity reaches to 0.320 Wm–1K–1. For PTDx, as the proportion of 3‐butoxythiophene increases, the UV spectrum appears red‐shifted, indicating an enhanced degree of p‐π conjugation. The thermal conductivity of PTDx is increased from 0.340 to 0.374 Wm–1K–1, which is around twice that of traditional thermoplastics. Molecular dynamics (MD) is used to simulate the changes in the volume and dihedral angle overlap of the polymer at different temperatures, and achieves the same result as the experiment. MD simulations and experimental measurements have shown that reducing steric hindrance and enhancing p‐π conjugation can increase the thermal conductivity of the polymer. Young's modulus of PTDx (around 1.86 GPa) is lower than that of conventional plastics, and its flexibility makes it more versatile. [ABSTRACT FROM AUTHOR]