A Study of the Degree of Fluorination in Regioregular Poly(3-hexylthiophene)

• DOI: 10.1021/acs.macromol.6b02365
• Publication Date: 2016-12-27T14:32:49Z
• Authors: J. Terence Blasko...; Thomas Bura; Serge Beaupré; Steven A. Lopez; Carl Roy; Julio de Goes Soares; Adam Oh; Jesse Quinn; Yuning Li; Alán Aspuru-Guzik; Mario Leclerc
• Keywords: 02 engineering and technology; 540; 0210 nano-technology; 620

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, respectively. 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 (Mn = 34 kg/mol, 98.5% rr), P3HT-33F (Mn = 46 k...