RESUMO
Surfactant-free emulsions are currently gaining increased interest due to their technofunctional, health-promoting, economic, biocompatible, and sustainable characteristics. Herein, we report an ultrastable, surfactant-free emulsion stabilized by the konjac glucomannan (KGM)-xanthan gum (XG) complex. The results suggested that KGM-XG tended to adsorb onto the oil/water interface, causing a reduction in interfacial tension. The emulsion droplets were less than 1 µm in diameter and had a narrow size distribution. Using laser confocal microscopy and cryo-SEM, it was observed that KGM-XG generated a compact film on the surface of emulsion droplets while simultaneously constructing a three-dimensional network in the continuous phase. Both of these factors contributed to the stability of the emulsion. The present study presents a straightforward approach for producing highly stable emulsions stabilized by polysaccharides. These emulsions can be effectively utilized to enhance the water resistance of cellulose paper, which is extensively employed in the packaging industry.
RESUMO
Nitrogen transfer from cyanide anion to an aldehyde is emerging as a promising method for the synthesis of aromatic nitriles. However, this method still suffers from a disadvantage that a use of stoichiometric Cu(II) or Cu(I) salts is required to enable the reaction. As we report herein, we overcame this drawback and developed a catalytic method for nitrogen transfer from cyanide anion to an alcohol via the complete cleavage of the C≡N triple bond using phen/Cu2 O as the catalyst. The present condition allowed a series of benzyl alcohols to be smoothly converted into aromatic nitriles in moderate to high yields. In addition, the present method could be extended to the conversion of cinnamic alcohol to 3-phenylacrylonitrile.
