Temperature-Tuning of Optical Properties and Molecular Aggregation in AnE-PVstat Copolymer Solution

The correlation between the optical and morphological properties of an anthracene-containing poly(phenylene ethynylene)-alt-(phenylenevinylene) statistical copolymer (AnE-PVstat) in solution has been investigated. As a function of temperature, the molecular aggregation in chloroform/chlorobenzene (CF:CB) solution was examined by means of absorbance and photoluminescence measurements. The study of the evolution of the 0–0 to the 0–1 photoluminescence (PL) ratio with temperature in the framework of the HJ-aggregate model unveiled the presence of both H- and J-like behaviors at room temperature. Upon increasing temperature, the interchain intermolecular coupling decreases, leading to a dissociation of H-aggregates. Hence, molecular torsions are facilitated, polymer planarity is reduced, and the intrachain electronic coupling decreases.