Star-Shaped Poly (Γ-Caprolactone-b-Ethylene Glycol): Synthesis, Characterization and Aggregation Behavior
Linear and Star-shaped PCL-b-PEG copolymers were synthesized through a two step process, including the first step to synthesize the star-shaped PCL through ring-opening polymerization of Γ-caprolactone initiated from multi-functional alcohol under the existence of tin(II) ethylhexanoate [Sn(Oct)2] catalyst, and the following step to couple the obtained star-shaped PCL with PEG segments using bi-functional linker. The structure of the polymers was confirmed by IR, NMR, GPC, et al. The aggregation behaviors of the star-shape copolymers were compared with that of the linear block copolymer with corresponding molecular weight of each arm, and the influences of structure factors were discussed.
Young-Ha Kim, Chong-Su Cho, Inn-Kyu Kang, Suk Young Kim and Oh Hyeong Kwon
Y. J. Fan et al., "Star-Shaped Poly (Γ-Caprolactone-b-Ethylene Glycol): Synthesis, Characterization and Aggregation Behavior", Key Engineering Materials, Vols. 342-343, pp. 725-728, 2007