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Hexagonal ferrites, materials widely used for permanent bard magnets, are currently commercially synthesized by multistep ceramic methods. Alternative routes are also multistep as well as being time‐consuming and expensive. Teh self‐propagating, high‐temperature synthesis (SHS) presented here is convenient, quick, inexpensive, and single‐step and it enables a range of ferrites, SrxBayFe12O19 (x + y equals; 1), to be prepared. The principles of SHS are briefly explained before the characterization of the reaction products, including their magnetic properties, is described.

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Polyaspartamides, which are termed to a variety of amide derivatives of poly(aspartic acid), one of the poly(amino acid)s or polypeptides, have been intensively investigated as biodegradable and biocompatible polymers with a broad range of potential biomedical applications as well as eco-friendly industrial uses. By discovering that polymers containing amidine or guanidine functionality have been shown to be reversibly responsive to carbon dioxide (CO 2 ), we have developed two polyaspartamide systems: novel CO 2 -responsive hydrogel and amphiphilic polyaspartamide derivative containing L-arginine. In this work, poly(2-hydroxyethyl aspartamide) derivative was modified with L-arginine unit (PHEA-Larg), before cross-linked by hexamethylene diisocyanate in the presence of dibutyltin dilaurate catalyst to provide a hydrogel having not only good gel strength, but reversible CO 2 absorption characteristics. On the other hand, amphiphilic polyaspartamide derivative containing hydrophobic long alkyl moiety (octyl) and L-arginine unit was synthesized, and the CO 2 -responsive solubility and molecular self-assembly behaviors of the systems were investigated. These new polyaspartamide systems have potential in several applications including CO 2 capture, CO 2 -responsive and switchable surface, sensor, smart hydrogel for controlled drug delivery system, etc.

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