Fractionated Crystallization of Defect-Free Poly(3-hexylthiophene)

Titelangaben

Kohn, Peter ; Hüttner, Sven ; Steiner, Ullrich ; Sommer, Michael:
Fractionated Crystallization of Defect-Free Poly(3-hexylthiophene).
In: ACS Macro Letters. Bd. 1 (2012) Heft 10 . - S. 1170-1175.
ISSN 2161-1653
DOI: https://doi.org/10.1021/mz3003769

Volltext

Link zum Volltext (externe URL):

Abstract

Fractionated crystallization (FC), a chain-sorting mechanism by length, is identified in well-defined, low molecular weight, and defect-free regioregular poly(3-hexylthiophene) by X-ray scattering and calorimetry of bulk samples. While wide-angle X-ray scattering (WAXS) qualitatively suggests that the degree of crystallinity is similar in all investigated samples, the melting enthalpies are largely different. We ascribe this to intricacies in the integration of the melting and crystallization peaks in calorimetric experiments, which is caused by FC occurring over a large temperature range. The extent of FC decreases with increasing molecular weight and increases with increasing polydispersity. The temperature-dependent investigation of the long period LP and the (100)-WAXS reflection of a sample in which FC is absent allows to disentangle effects from main-chain and side-chain crystallization.