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Title: A study of the degree of fluorination in regioregular poly(3-hexylthiophene)

Here, we systematically varied the degree of fluorination along the backbone of a series of highly regioregular 3-hexylthiophene-based polymers, P3HT-50F, P3HT-33F and P3HT-25F, in which 50%, 33% and 25% of the thiophene units within the polymer chain contain fluorine atoms in the available 4-position. These materials were homopolymerized using the Kumada catalyst transfer polycondensation method from a set of mono-fluorinated bi-, ter- and quarterthiophenes, to ensure high polymer regioregularity and evenly-spaced fluorine atoms along the conjugated thiophene backbone. The monomers were obtained from a synthetic route consisting of iterative Migita-Stille couplings of fluorinated and non-fluorinated 3- hexylthiophenes. The effect of the fluorine atoms on both polymer structure and properties is presented, with supporting quantum mechanical calculations that rationalize the intrinsic conformation preferences of the three P3HT derivatives. P3HT-50F (M¯ n = 34 kg/mol, 98.5% rr), P3HT-33F (M¯ n = 46 kg/mol, 98% rr) and P3HT-25F (M¯ n = 53 kg/mol, 95% rr) displayed HOMO levels of -5.34, -5.26 and -5.24 eV, bandgaps of 1.98, 1.98 and 1.97 eV, and average field-effect transistor hole mobilities of 4.5 × 10 -3, 2.7 × 10 -2, and 1.2 × 10 -2 cm 2 V -1s -1, respectively.
Authors:
 [1] ;  [1] ;  [1] ;  [2] ;  [1] ;  [2] ;  [2] ;  [3] ;  [3] ; ORCiD logo [2] ; ORCiD logo [1]
  1. Univ. Laval, Quebec City (Canada)
  2. Harvard Univ., Cambridge, MA (United States)
  3. Univ. of Waterloo, Waterloo, ON (Canada)
Publication Date:
Grant/Contract Number:
SC0015959
Type:
Accepted Manuscript
Journal Name:
Macromolecules
Additional Journal Information:
Journal Volume: 50; Journal Issue: 1; Journal ID: ISSN 0024-9297
Publisher:
American Chemical Society
Research Org:
Harvard Univ., Cambridge, MA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE
OSTI Identifier:
1336363