Study on self-assembly properties of aryl-alkyl hyperbranched polyesters with carboxylic end groups

摘要

Carboxylic ended aryl-alkyl hyperbranched polyester poly(5-hydroxyethoxyisophthalic acid) (PHEIA) was synthesized and employed for an eletrostatic layer-by-layer self-assembly procedure, in which poly(diallydimethylammonium chloride) (PDAC) was used as the polyanion while PHEIA, acted as the polycation. From both aqueous solution and water-THF mixture of PHEIA, self-assembly films have been successfully formed as monitored by UV-Vis spectroscopy and contact angle measuring device. In the self-assembled surface where PHEIA acted as outmost layer, sphere-like particles with uniform diameter was observed by Atom Force Microscopy (AFM). This phenomenon should be attributed to the aggregation of PHEIA. Furthermore, the layer-bu-layer self-assembly procedure provided a favorable method for adjusting the hydrophilicity of the substrate without much interpenetration between these two polyelectrolyte layers.