Layered double hydroxides (LDHs) are popular functional fillers increasingly used in composite materials. They can be designed via metal and anion selection as well as the specific processing method to prepare structures with desired functional properties. This makes LDHs suitable for many different applications, including as flame‐retardants, UV stabilizers, and anti‐microbial agents in polymer nanocomposites as well as a photo‐absorber in a solar cell. Here an overview of LDH synthesis and modification, composite preparation as well as characterization is given to highlight the unique ability for customization of LDH.

Safe application of water-insoluble acaricides requires fast release from solid dosage systems into aquatic environments. Dextrin is a water-soluble form of partially hydrolyzed starch, which may be used as matrix material for these systems if retrogradation can be inhibited by the inclusion of nanofillers. Several glycerol-plasticized thermoplastic dextrin-based nanocomposites were prepared with a twin-screw extrusion-compounding process. The nanofillers included a layered double hydroxide (LDH), cellulose nanofibers (CNF), and stearic acid. The time-dependent retrogradation of the compounds was monitored by X-ray diffraction (XRD) and dynamic mechanical thermal analysis (DMA). XRD showed that composite samples that included stearic acid in the formulation led to the formation of an amylose-lipid complex and a stable crystallinity during aging. The most promising nanocomposite included both stearic acid and CNF. It was selected as the carrier material for the water-insoluble acaricide Amitraz. Fast release rates were observed for composites containing 5, 10, and 20% (w/w) of the pesticide. A significant reduction in the particle size of the released Amitraz powder was observed, which is ascribed to the high-temperature compounding procedure.

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The potential of a blended cellulose solvent, consisting of a 1:1 mass ratio of choline chloride with the ionic liquid 1-ethyl-3-methylimadazolium acetate, was evaluated by using a film-casting technique. When comparing films produced with the neat ionic liquid to casting products from the mixed solvent, mechanical properties could largely be retained, while transparency was somewhat impaired. This is attributed to a fibrous microstructure and a higher degree of crystallinity caused by incomplete dissolution of the initial cellulose fibres. The presence of these residual fibres significantly reduced shrinkage during the film formation process. Functional group analyses, together with information on their crystallographic structure, proved that these film-like products should be classified as all-cellulose composites (ACCs). Statistical analyses of tensile properties justify further research on the mixed solvent system for cellulose processing.