Synthesis and Application of a Hyperbranched Polyester Quaternary Ammonium Surfactant

In the presence of the alkaline catalyst sodium hydroxide, the intermediate of hyperbranched polyester (H20Cl) was prepared by the modification of the hyperbranched polyester Boltorn H20 with epichlorohydrin. Then a new kind of quaternary ammonium functionalized hyperbranched polyester (H20C16 N) was synthesized by the reaction of H20Cl and hexadecyldimethylamine. The characteristics of H20C16 N were determined by FT-IR, H-1 NMR and TGA. The molecular and molecular weight distribution of H20C16 N were determined by Gel Permeation Chromatography (GPC) and the surface activities of H20C16 N including surface tension (gamma) and the critical micelle concentration (CMC) were measured at 25 A degrees C. The H20C16 N reduced the surface tension of water to 30.81 mN/m at concentration levels of 7.94 x 10(-5) mol L-1 and micellization free energies of the quaternary ammonium salt in its solution showed a good tendency towards adsorption at interfaces. The H20C16 N was applied to the silk fabric. An antimicrobial test of the treated fabrics against Escherichia coli and Staphylococcus aureus was carried out. SEM and XPS analysis were performed to study the dispersion of H20C16 N onto the fabric. All results exhibited excellent antibacterial properties of the hyperbranched polyester quaternary ammonium salt.