Figure 1.

Synthetic process of poloxamer188-b-PCL polymers (A). The block polymers were synthesized via the ring-opening polymerization with poloxamer188 and ε-CL as starting materials; FTIR spectra of ε-CL, poloxamer188, and poloxamer188-b-PCL polymers (B). The absorption peak of –C=O group was found in the spectrum of final polymer, which confirmed the obtaining of the poloxamer188-b-PCL polymers; Raman spectra of ε-CL, poloxamer188, and poloxamer188-b-PCL polymers (C); ¹H NMR spectrum of poloxamer188-b-PCL polymers (D). The ¹H NMR spectrum also confirmed the obtaining of poloxamer188-b-PCL polymers; GPC curve of poloxamer188-b-PCL polymers (E). The Mw of obtained polymer was 12,276 D; TGA curves of poloxamer188 and poloxamer188-b-PCL polymers (F). TGA curves indicated that the poloxamer188-b-PCL polymers improved the thermo-stability of poloxamer188.