Synthesis of Poly(3-Hexylthiophene) with High Molecular Weight and Small Polydispersity

Abstract

Regioregular head-tail poly(3-hexylthiophenes) (HT-P3HT) with a controlled high molecular weight and a small polydispersity have been synthesized via an improved Kumada catalyst-transfer polycondensation (KCTP) by using the new-prepared hexylmagnesium bromide as the Grignard reagent. As the amount of nickel catalyst dichloro[1,3-diphenylphosphinopropane] nickel (Ni(dppp)Cl2) was 0.5% mol of the amount of monomer 2,5-dibromo-3-hexylthiophene (DBHT) we can obtain a HT-P3HT with a high molecular weight Mn (38 449) and a small polydspersity (1.18). By using of LiCl as a co-catalyst, the regioregularity of the P3HT with high molecular weight (40 270) is maintained and the PDI (1.03) is smaller than that of the P3HT polymerized in the absence of LiCl but the conversion ratio of the monomer is promoted. The HT-P3HT with high molecular weight and small polydispersity will be an attractive candidate applied in solar cells.

Modified P3HT materials as hole transport layers for flexible perovskite solar cells

“…The Stille approach is characterized by a remarkable versatility and feasibility, nevertheless toxicity and harmfulness of the organic tin derivatives undermine its sustainability [35,36]. To overcome these limitations, Kumada polycondensation was explored as greener alternative to obtain polymers characterized by higher molecular weight and regioregularity [37]. In the latter, the BDT concentration in the P3HT backbone could be tuned to very low values avoiding the tedious synthesis of specific oligomers.…”