Synthesis and Characterization of ABBA Block Copolymer of Glycolide and ε-Caprolactone

来源 :Chemical Research in Chinese Universities | 被引量 : 0次 | 上传用户:deiaw
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A biodegradable ABBA block copolymer was synthesized via the ring-opening co-polymerization of ~ε-caprolactone(CL, B) and glycolide(A) by means of step polymerization in the presence of ethylene glycol as an initiator and stannous octanoate as a catalyst at 110 ℃ for 48 h. The molecular length of the PCL pre-polymer(BB) could be adjusted by controlling the molar ratio of the ethylene glycol initiator to ε-caprolactone monomer. The structure and the composition of the block copolymer were determined by the weight ratio of the monomer glycolide(A) to PCL pre-polymer(BB). The block copolymers were characterized by ~ 1H NMR, GPC, DSC and X-ray. The results confirm the successful synthesis of an ABBA block copolymer. A biodegradable ABBA block copolymer was synthesized via the ring-opening co-polymerization of ~ ε-caprolactone (CL, B) and glycolide (A) by means of step polymerization in the presence of ethylene glycol as an initiator and stannous octanoate as a catalyst at 110 ° C for 48 h. The molecular length of the PCL pre-polymer (BB) could be adjusted by controlling the molar ratio of the ethylene glycol initiator to ε-caprolactone monomer. The structure and the composition of the block copolymer were determined by the weight ratio of the monomer glycolide (A) to PCL pre-polymer (BB). The block copolymers were characterized by ~ 1H NMR, GPC, DSC and X-ray. The results confirm the successful synthesis of an ABBA block copolymer.
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