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Among odd‐nylons, nylon‐5 exhibits the highest remanent polarization and is thus a desirable material for many applications of ferroelectric polymers. However, nylon‐5 has never been used as a ferroelectric material, because the synthesis of nylon‐5 and its processing into thin films are challenging. This work revisits the synthesis of nylon‐5 via anionic ring opening polymerization (AROP) and studies the effect of reaction time and scale‐up on (i) molecular weight (Mn), (ii) melting point (Tm), (iii) yield, and (iv) ferroelectric properties. For the first time, the molecular weight of nylon‐5 is characterized via size exclusion chromatography (SEC), nuclear magnetic resonance (NMR) spectroscopy, as well as matrix assisted laser desorption ionization time of flight mass spectroscopy (MALDI ToF‐MS), showing Mn values of up to 12 500 g mol‐1. Extended reaction times and the synthesis on a larger scale increase the molecular weight and yield. Nylon‐5 thin films are fabricated from a TFA:acetone (60:40 mol%) solvent mixture. Nylon‐5 thin‐film capacitors are ferroelectric and show a remanent polarization as high as 12.5 ± 0.5 μC cm‐2, which is stable in time. The high remanent polarization values, combined with the facile solution processing, render nylon‐5 a promising candidate for future microelectronic and multi‐ferroic applications. [ABSTRACT FROM AUTHOR]

Supramolecular antioxidant complexes are prepared by the non-covalent assembly of succinic acid-modified hyperbranched polyglycerols (PGSAs) and tyramine antioxidant compounds. Using this approach, various supramolecular dendritic poly­mers based on carboxylic acid-modified hyperbranched polyglycerol with different molecular weights and different numbers of antioxidant phenols are prepared and characterized by FTIR and NMR spectroscopy as well as via dynamic light scattering (DLS). The local phenolic concentration in this supramolecular architecture plays a key role for their enhanced antioxidant capacity, as shown by oxygen radical absorbance capacity assay (ORAC). [ABSTRACT FROM AUTHOR]

Multiple hydroxamic acids are introduced at poly(ethylene glycol) (PEG) via copolymerization of ethylene oxide with a novel epoxide monomer containing a 1,4,2‐dioxazole‐protected hydroxamic acid (HAAGE). AB‐ and ABA‐type di‐ and triblock copolymers as well as statistical copolymers of HAAGE and ethylene oxide are prepared in a molecular weight range between 2600 and 12 000 g mol−1 with low dispersities (Ð < 1.2). Cleavage of the acetal protecting group after the polymerization is achieved by mild acidic treatment, releasing multiple free hydroxamic acids tethered to the polyether backbone. The chelation properties of different polymer architectures (statistical versus diblock and ABA triblock) are investigated and compared with regard to the number and position of hydroxamic acids. Separation of the hydroxamic acid units by at least 5 ethylene glycol monomer units is found to be essential for high Fe(III) binding efficiency, while block copolymers are observed to be the best‐suited architecture for polymer network and hydrogel formation via Fe(III) chelation. [ABSTRACT FROM AUTHOR]