writer：Guowei Wang, Xiaolan Luo, Yannan Zhang, Junlian Huang*
keywords：Click Chemistry
source：期刊
specific source：J. Polym. Sci. Part A: Polym. Chem. 2009, 47, 4800-4810.
Issue time：2009年

The dendrimer-like copolymers [PEEGE-(PS/PEO)]n (n
2) based on the star[Polystyrene-Poly(ethylene oxide)-Poly(ethoxyethyl glycidyl ether)] [star(PS-PEO-(PEEGE-OH))] terpolymers were synthesized by click chemistry. First, the star-shaped copolymers star[PS-PEO-(PEEGE-Alkyne)] (also termed as [PEEGE-(PS/PEO)]1) were synthesized by the reaction of hydroxyl end group at PEEGE arm (on star[PS-PEO-(PEEGE-OH)]) with propargyl bromide. Then, the small molecule 1,4-diazidobutane (DAB) with two azide groups and pentaerythritol tetrakis (2-azidoisobutyrate) (PTAB) with four azide groups were synthesized and reacted with [PEEGE-(PS/PEO)]1 by the click chemistry for dendrimer-like [PEEGE-(PS/PEO)]2 and [PEEGE-(PS/PEO)]4, respectively. However, in the latter case, only the [PEEGE-(PS/PEO)]3 was formed as the main product because of the steric effect. The final dendrimer-like [PEEGE-(PS/PEO)]n copolymers were characterized by SEC and 1H-NMR in detail. Comparing with the SEC of their precursor [PEEGE-(PS/PEO)]1, the curves of [PEEGE-(PS/PEO)]2 was shifted to the shorter elution time, while that of [PEEGE-(PS/PEO)]n (n
3) was shifted to the longer elution time, which was attributed to the different hydrodynamic volume derived from their separate structures and compositions in THF solution.