Vital wheat gluten can be modified to produce superabsorbent materials. In the study by George Robertson et al., vital wheat gluten is reacted with phosphoric acid to produce differing absorption properties. The cover, created with the software Mathematica, shows a digitally enhanced, 2D gel electrophoresis of a wheat gluten polymer that is chemically deconstructed to eliminate disulfide links and minimize secondary interactions. The peaks represent mass fractions of polymer subunits on a plane of isoelectric points and relative molecular mass. All subunits can have charge-charge interactions or hydrogen bonding, but only those in the light green and light blue regions can extend chains. Acid treatment significantly alters this topography and produces an unusually high water free swelling capacity. DOI: 10.1002/app.39440

The use of extruders as continuous polymerization reactors for polymer synthesis is growing rapidly. By controlling the temperatures of various barrels alone without supplying additives, Xieyao Yuan et al. synthesize two kinds of styrene-isoprene copolymers with high isoprene content using reactive extrusion. The transmission electron micrograph on the cover reveals the microdomains of a styrene-isoprene diblock copolymer synthesized by adding styrene and isoprene monomers at the first and the fifth barrel, respectively. The microdomains are influenced by both the content of each phase and the molecular weight of each block. Compared with conventional polymerization reactors, extruders have the advantage of continuous bulk polymerization without any solvent. DOI: 10.1002/app.39429

To improve sustained and controlled drug-delivery systems, the construction of polymeric matrices with a high loading of bioactive molecules and controllable release under physiological conditions is vitally important. Renbao Gu et al. fabricate a hydrogel nanocomposite film by alternating deposition of core-shell poly[(dimethylimino)(2-hydroxy-1,3-propanedily) chloride] (PDMIHPC)-laponite nanocomposite dispersion and poly(acrylic acid) (PAA). This layer-by-layer assembly process undergoes linear growth. The cover shows a SEM cross section of the hydrogel nanocomposite film after loading with methylene blue dye (MB). The loading capacity of the film for MB is as large as 4.48 μg/cm² per bilayer due to the introduction of core-shell PDMIHPC-laponite as a film component. This hydrogel nanocomposite film shows good pH-triggered loading-release reversibility, and could be an advanced material for applications in triggered controlled release systems. DOI: 10.1002/app.39352

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