Supramolecular complexation of C with branched polyethylene.

Fullerene C is a ubiquitous material for application in organic electronics and nanotechnology, due to its desirable optoelectronic properties including good molecular orbital alignment with electron-rich donor materials, as well as high and isotropic charge carrier mobility. However, C possesses two limitations that hinder its integration into large-scale devices: (1) poor solubility in common organic solvents leading to expensive device processing, and (2) poor optical absorbance in the visible portion of the spectrum. Covalent functionalization has long been the standard for introducing structural tunability into molecular design, but non-covalent interactions have emerged as an alternative strategy to tailor C-based materials, offering a versatile and tuneable alternative to novel functional materials and applications.

Polyacetylene Revisited: A Computational Study of the Molecular Engineering of N-type Polyacetylene.

The development of stable and highly conductive polymers, particularly -type materials, remains an outstanding challenge in organic electronics. -doped polyacetylene has long been studied as a highly conductive organic -type material but suffers from extremely poor stability. Herein, we use DFT to model a series of -doped polyacetylene derivatives, which have been functionalized with a range of electron-withdrawing substituents, with the goal of identifying attractive candidates for synthesis.

Trends in Conjugated Chalcogenophenes: A Theoretical Study.

Heavy atom substitution in chalcogenophenes is a versatile strategy for tailoring and ultimately improving conjugated polymer properties. While thiophene monomers are commonly implemented in polymer designs, relatively little is known regarding the molecular properties of the heavier chalcogenophenes. Herein, we use density functional theory (DFT) calculations to examine how group 16 heteroatoms, including the radioactive polonium, affect polychalcogenophene properties including bond length, chain twisting, aromaticity, and optical properties.

Isolation of Living Conjugated Polymer Chains.

Living polymerizations currently play a central role in polymer chemistry. However, one feature of these polymerizations is often overlooked, namely, the isolation of living polymer chains. Herein we report the isolation of living π-conjugated polymer chains, synthesized by catalyst-transfer polycondensation.

The role of halogens in the catalyst transfer polycondensation for π-conjugated polymers.

Catalyst transfer polycondensation is the only method to prepare π-conjugated polymers in a chain-growth manner, yet several aspects that underlie this polymerization are not fully understood. Here, we investigate the nickel-catalyzed polymerization mechanisms of a series of thiophene monomers bearing different halogen functionalities (Cl, Br, I). We have discovered the significant role that halogens and magnesium salts play in this polymerization.

Evidence for the chain-growth synthesis of statistical π-conjugated donor-acceptor copolymers.

The synthesis of a series of dithienosilole-benzotriazole donor-acceptor statistical copolymers with various donor-acceptor ratios is reported, prepared by Kumada catalyst-transfer polymerization. Statistical copolymer structure is verified by (1) H NMR and optical absorption spectroscopy, and supported by density functional theory (DFT) calculations. The copolymers exhibit a single optical absorption band that lies between dithienosilole and benzotriazole homopolymers, which shifts with varying donor-acceptor content.

Controlled Synthesis of Fully π-Conjugated Donor-Acceptor Block Copolymers Using a Ni(II) Diimine Catalyst.

We use a Ni(II) diimine catalyst to prepare the first examples of the controlled synthesis of electron-rich/electron-deficient all-conjugated diblock copolymers. These catalysts are able to control polymerizations of both electron-rich and electron-deficient monomers, which we attribute to strong association to both monomer types. Block copolymers are prepared by controlled chain extension, and their structure is verified by gel permeation chromatography, H NMR, electrochemistry, calorimetry, and atomic force microscopy.