A “Rigid–Flexible” Approach for Processable Perylene Diimide-Based Polymers: Influence of the Specific Architecture on the Morphological, Dielectric, Optical, and Electronic Properties

Abstract

Conjugation-break flexible spacers in-between πconjugated segments were utilized herein toward processable perylene diimide (PDI)-based polymers. Aromatic−aliphatic PDIbased polymers were developed via the two-phase polyetherification of a phenol-difunctional PDI monomer and aliphatic dibromides. These polyethers showed excellent solubility and filmforming ability and deep lowest unoccupied molecular orbital (LUMO) levels (−4.0 to −3.85 eV), indicating the preservation of good electron-accepting character or characteristics, despite the non-conjugated segments. Their thermodynamic properties, local dynamics, and ionic conductivity demonstrate the suppression of PDI's inherent tendency for aggregation and crystallization, suggesting PDI-polyethers as versatile candidates for organic electronic applications. Their dynamics investigation using dielectric spectroscopy revealed weak dipole moments arising from the distortion of the planar perylene cores. Blends of the PDI-polyethers (as electron acceptors) with P3HT (as a potential electron donor component) showed UV−vis absorbances from 350 to 650 nm and a tendency of the PDI-polyethers to intertwine with rr-P3HT and restrain its high crystallization tendency.

Nucleophilic Aromatic Substitution of Pentafluorophenyl-Substituted Quinoline with a Functional Perylene: A Route to the Modification of Semiconducting Polymers

“…More specifically, it undergoes nucleophilic aromatic substitutions with a variety of nucleophiles (alcohols, amines, phosphates, and thiols) offering the possibility of the controlled modification of fluorine atoms, and providing favorable solubility [ 42 , 43 ]. The perflurophenyl group has also been studied in semiconducting polymers such as poly(3-hexyl thiophene) P3HT for controlled functional semiconducting materials [ 44 , 45 , 46 , 47 , 48 ]. These reasons highlight the PFP group as a promising moiety for the activation of various molecules and macromolecules.…”

“…Previously, we developed hydroxyphenyl-PDI molecules by attaching hydroxyphenyl groups to both or to one of the bay positions of the PDI core [ 47 , 48 ]. These hydroxyphenyl-PDIs were used for the substitution of perflurophenyl quinoline-based small molecules to afford ether-based, PDI-quinoline electron accepting small molecules [ 47 ].…”

“…These hydroxyphenyl-PDIs were used for the substitution of perflurophenyl quinoline-based small molecules to afford ether-based, PDI-quinoline electron accepting small molecules [ 47 ]. In a second case, the di-hydroxyphenyl-PDI monomer was polymerized with aliphatic dibromides, producing rigid–flexible aromatic–aliphatic polyethers [ 48 ]. Moreover, some of our groups’ earlier efforts were devoted to electron-accepting perfluorophenyl-quinolines combined with single-wall carbon nanotubes (SWCNTs) or fullerene derivatives (C 60 , C 70 , PCBM), as electron-accepting hybrid additives for OPVs [ 49 , 50 , 51 ].…”

Electron Transporting Perylene Diimide-Based Random Terpolymers with Variable Co-Monomer Feed Ratio: A Route to All-Polymer-Based Photodiodes

“…The class of PDI electron acceptors is highly favorable; PDIs are easily processable by most organic solvents, their absorption profile can be tuned on demand via simple chemistry, and their cost is lower than of fullerene derivatives. Most importantly, the LUMO energy level of molecular PDI derivatives is deeper than the electron trapping sites that have been identified as the universal bottleneck for trap-free electron transport in organic semiconductors. , Non-planar structures combining different organic building blocks have been investigated in order to overcome the intense self-aggregation of PDI derivatives that lead to oversized domains and ultimately poor photovoltaic performance. , Although small molecule acceptors based on PDI have been more widely used, some PDI-based copolymers have been also reported − giving promising results.…”

Ternary Blend Organic Solar Cells Incorporating Ductile Conjugated Polymers with Conjugation Break Spacers

“…Recently, conjugation break spacers (CBS) were introduced to the field of organic electronics. ,− A CBS unit is a nonconjugated segment, such as a flexible alkyl chain that disrupts the conjugation along the polymer backbone. Initially, conjugation breakers were designed to improve processability of polymer semiconductors.…”