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To produce textiles that regenerate antimicrobial surfaces wash after wash, we synthesized and immobilized antimicrobial silver nanoparticles (Ag NPs) within brown cotton fibers. This composite for...

Corn protein (zein) was melt-processed with methylenediphenyl 4,4′-diisocyanate (MDI) using triethylamine (TEA) as a catalyst to facilitate the reaction of the isocyanate groups with the nucleophilic moieties present on zein. The product of the reaction was examined using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) to monitor changes in molecular weight. Techniques used to evaluate property changes after reaction included FTIR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and evaluation of mechanical properties. Our findings demonstrated that zein reacts with MDI in the melt state generating higher molecular weight compounds that after compression molding have improved physical properties and solvent resistance.

The conversions of N-(o-bromobenzyl)methoxylamine to N-acetylbenzoazetine (1), of N-(3-(o-bromophenyl)-n-propyl)methoxylamine to N-acetyltetrahydroquinoline (2), and of N-(4-(o-bromophenyl)-n-butyl)-methoxylamine to N-acetylbenzazapine (3) illustrate the use of this displacement reaction to form nitrogen-containing rings in an exocyclic reaction mode. An x-ray structural determination is reported for 1. The formations of anilides by amination of aromatic organolithium reagents with lithium methoxylamide is also reported. Lithium reagents are found to be more effective than Grignard, copper, or zinc reagents in these displacements, and the yields decrease as the size of the substituents around nitrogen increases. The endocyclic restriction test is used to show that this displacement on nitrogen cannot occur within the endocyclic confines of a seven-membered ring. A S{sub N}2 reaction pathway in a lithium complex is considered to be supported by these results.