The Synthesizaion Of Hyperbranched Poly(Amide-ester)s And The Properties Of Its Aqueous Solutions

The hyperbranched polymer have been attracted considerable attention due to its highly branched units with peculiar properties, such as low melt viscosity, dissolubility, non-entanglement and a large number of active end groups. Hyperbranched polymers were widely used in many fields, such as functional materials, clinical medicine, supramolecular chemistry, biochemistry and pharmaceutical industry. In this paper, a hyperbranched poly(amide-ester)s with end active hydroxyl groups was synthesized, and characterized by FTIR, MS, DSC, VPO techniques. Furthermore, the aqueous solutions properties was investigated by viscometer, DSC and NMR spectrum, the results indicated that the aqueous solutions have a typical behavior of volume phase transition(VPT).The paper have three sections, and the main results are as following:In sec.1, the overviews of the progress in the hyperbranched polymers science were given.In sec.2, the new type hyperbranched poly(amide-ester)s was synthesized by polycondensation reaction of the succinic anhydride (AA ) with diethanolamine (B'B2). The pyridine was used as solvent and protecting agent and the products werecharacterized by FTIR, MS, DSC, VPO techniques.In sec.3, the viscosity behavior of a hyperbranched poly (amide-ester)s in the aqueous solutions was investigated. The results show that there was an abrupt changeof the limiting viscosity number ([η]) as the temperature varied. The limitingviscosity number ([η])] was decreases sharply when the temperature was over thelower critical solution temperature. The behavior observed in the paper was in according with that of the volume phase transition reported in the Refs. The reliable description of the result was referred to the hydrogen bond networks formed in the aqueous solutions. As the temperature increased, the hydrogen bonds networks werebroken, and then the volume phase transition took place, and the limiting viscosity number ([η]) was decreased sharply. The results were also agreement with thatdetermined by the DSC and NMR techniques.