Interactions between Individual Charged Dendronized Polymers and Surfaces

Abstract

Polymethacrylate-based amino-terminated dendronized polymers up to generation 5 were adsorbed on mica, hydrophobized mica, and gold and studied with the atomic force microscope (AFM). These studies were carried out in a mildly acidic electrolyte solution where these polymers are fully ionized. The polymers were imaged in intermitted contact mode in solution, and desorption forces of individual polymer chains were investigated by single molecule force spectroscopy. The adsorbed chains have a uniform envelope up to generation 4, but the generation 5 polymer has a pronounced pearl-necklace structure. Force spectroscopy clearly reflects this difference. While lower generation polymers show peeling events with a single force plateau or pulling event with a single spike, those of generation 5 are characterized by two different force plateaus as well as multiple pulling events. These features are probably related to the unwrapping of pearls in the polymer backbone. We suspect that the pearls result from the high hydrophobicity of the polymer backbone.

Recording stretching response of single polymer chains adsorbed on solid substrates

“…Recently, such experiments were also carried out with two AFM-tips, which further provide time-dependent properties of a single polymer chain [23]. A peeling event is characterized with a plateau in the force curve, which reflects the force that is necessary to peel off the adsorbed molecule [30][31][32][33][34][35][36]. These forces reflect the affinity of the molecules to the surface, and can be related to the type of substrate and its charge.…”

Interactions in blends of dendronized polymeric nanocomposites with some common drugs

“…In contrast, macromolecules with large molecular weights are used directly in industry. The most significant difference between small and large molecules is that macromolecules, unlike small molecules, do not have a specific shape and therefore lack predictable properties . For instance, the diameter of the polymers can be changed by changing their physical environment.…”

Interaction of dendronized polymeric nanocomposites with isomeric cyclohexanediols

“…This chemical structure imparts the macromolecules with special properties, making their behavior interesting from different perspectives. These branched polymers should be able to entrap and receive small guest molecules and can therefore be used as matrices for the delivery of drugs, catalysts, and dyes and for compatibilization of small molecules, etc., via host–guest interactions . The literature contains several reports in which these compounds are used for the aforementioned purposes and as drug delivery, thermal response, and optoelectronic materials …”

“…Low‐molecular‐weight molecules are often used as carriers and to prepare new compounds, such as pharmaceutical compounds, dyes, and catalysts . High‐molecular‐weight macromolecules are used in industry.…”

“…High‐molecular‐weight macromolecules are used in industry. The most significant difference between small and large molecules is that the macromolecules do not have a specific shape and therefore lack predictable properties, unlike small molecules . For instance, the diameter of polymers can be changed by altering their physical environment.…”