Assembling semiconducting molecules by covalent attachment to a lamellar crystalline polymer substrate

Abstract

SummaryWe have investigated the potential of polymers containing precisely spaced side-branches for thin film applications, particularly in the context of organic electronics. Upon crystallization, the side-branches were excluded from the crystalline core of a lamellar crystal. Thus, the surfaces of these crystals were covered by side-branches. By using carboxyl groups as side-branches, which allow for chemical reactions, we could functionalize the crystal with semiconducting molecules. Here, we compare properties of crystals differing in size: small nanocrystals and large single crystals. By assembling nanocrystals on a Langmuir trough, large areas could be covered by monolayers consisting of randomly arranged nanocrystals. Alternatively, we used a method based on local supersaturation to grow large area single crystals of the precisely side-branched polymer from solution. Attachment of the semiconducting molecules to the lamellar surface of large single crystals was possible, however, only after an appropriate annealing procedure. As a function of the duration of the grafting process, the morphology of the resulting layer of semiconducting molecules changed from patchy to compact.

Anisotropic Colloidal Particles by Molecular Self‐Assembly: Synthesis and Application

“…Meanwhile, the formed crystalline particles have a very wide size distribution as the nucleation events do happen not at the same time. The micro‐ or nanocrystals in the range of colloidal scale have relatively small sizes in all dimensions, and could be single crystals [57] or multi‐crystals [58] . In this section, we limit our discussion to micro/nanosized polymer single crystals.…”

“…The micro-or nanocrystals in the range of colloidal scale have relatively small sizes in all dimensions, and could be single crystals [57] or multi-crystals. [58] In this section, we limit our discussion to micro/nanosized polymer single crystals.…”

Adsorption of sterically-stabilized diblock copolymer nanoparticles at the oil–water interface: effect of charged end-groups on interfacial rheology

“…For example, long-range repulsive interactions and high surface pressures at large interfacial areas are observed for polyethylene nanocrystals comprising one carboxylic acid per 45 carbon atoms once this substituent undergoes ionization on raising the solution pH. 97 However, such long-range interactions are much softer than the steric interactions reported for octadecylamine. In the case of the sterically-stabilized nanoparticles reported herein, the attractive van der Waals interactions between the hydrophobic PMMA (or PBzMA) cores should be offset by the steric or electrosteric repulsive interactions between the solvated neutral or charged stabilizer chains.…”

Thin-layer studies on surface functionalization of polyetherimide: Hydrolysis versus amidation

“…Rather, the carboxylate groups, which were not converted to NHS esters, could undergo ionic hydrogen bonds with the amines of some TAPP molecules. These adsorbates would then direct the assembly of further TAPP molecules at the polymer surface via π-π stacking [25]. This additional cohesive layer explains the increase of the modulus.…”