writer：Wei-Xing Chen, Xiao-Dong Fan *, Yi Huang, Yu-Yang Liu, Le Sun
keywords：star-like amphiphilic copolymer,RAFT polymerization,controlled drug release
source：期刊
specific source：Reactive & Functional Polymers 69 (2009) 97–104
Issue time：2008年

A star-like amphiphilic copolymer was synthesized via RAFT polymerization by using a pentaerythritolbased
compound (PTDBA) as a chain transfer agent with Styrene and DMAEMA as monomers. The polymer
structure was characterized by FTIR, 1H NMR, 13C NMR and SEC/MALLS. After the retardation period,
the molecular weight of PS-CTA and PMMA-CTA increased linearly with monomer conversion. The
amphiphilic copolymer self-assembled into spherical micelles when water was added into its DMF solution.
The particle size and polydispersity index (PDI) of the micelles in deionized water were about
406 nm and 0.113, respectively. In a pH 10 buffer solution and low micelle concentration, the micelle size
decreased with temperature increase. At higher temperatures and micelle concentrations the size
increased, resulting in precipitation among agglomerating micelles. This phenomenon was not observed
in deionized water. Furthermore, the copolymer effectively prolonged the release time of chlorambucil
(CLB) in deionized water.