Synthesis and encapsulation properties of dendronized polymer with Fréchet-type dendrons peripherally decorated by carboxylic acid functionalization

Graphical Abstract

A kind of water-soluble dendronized polymer (denpol) with Fréchet-type dendrons decorated by carboxylic acid functionalization peripherally is synthesized via macromonomer route and hydrolysis reaction. This denpol could act in aqueous solution as amphiphilic unimolecular container to encapsulate various polycyclic aromatic molecules efficiently, which may be applied to separation, drug-delivery, and microreactor.

Abstract

A new carboxylic acid-terminated dendronized polymer (denpol), constructed with linear chain attaching Fréchet-type dendrons at each repeat unit, has been designed and synthesized through a combination of macromonomer route and hydrolysis reaction. The resulting denpol exhibits excellent solubility in aqueous solution for pH ≥ 6, and significantly the denpol also encapsulates various aromatic molecules efficiently. The results of UV–vis and fluorescence spectra indicate that hydrophobic and π-π interactions bring into effect between the water-insoluble organic molecules and the denpol. Moreover, the photoisomerization of azobenzene solubilized in denpol aqueous solution was investigated, which indicated that trans-to-cis and cis-to-trans conversions were first-order reactions. The enhancement of photoisomerization property may attribute to the proper microenvironment in the denpol. Therefore, the denpol is expected to be a potential candidate as amphiphilic unimolecular container. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4564–4574, 2008