Highly regioregular poly-3-alkylthiophenes: Influence of the structure on photoluminescence

A class of regioregular poly-3-alkylthiophenes was synthesized via a new and simple synthetic procedure. These polymers exhibit a regioregularity as high as 95-100% and show different thermal behaviour depending on the length of the side chain. The high conjugation length reached is responsible for a red-orange emission with photoluminescence (PL) quantum efficiencies of about 45% in solution. The study of the PL of spin coated films at different temperatures allows to correlate the PL spectra with the structure of the polymers as detected by XRD.