In-plane Thermal Conductivity Measurement of Conjugated Polymer Films by Membrane-based AC Calorimetry

Abstract

We investigated the anisotropy in the thermal conductivities of π-conjugated polymer films of poly(3-hexylthiophene-2,5-diyl), poly[2-methoxy-5-(2′-ethylhexyloxy)-p-phenylenevinylene], poly(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene), and poly(3,4-ethylenedioxythiophene):tosylate (PEDOT:Tos). It was found that the in-plane thermal conductivity of the films, measured by membrane-based ac calorimetry, was approximately two times higher than the through-plane one measured by the 3ω method. We also found that the anisotropy of the electronic contribution is not negligible for the PEDOT:Tos films.