Synthesis and characterization of new biodegradable thermosensitive polyphosphazenes with lactic aci

来源 :Chinese Chemical Letters | 被引量 : 0次 | 上传用户:LVBIN0077
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Two novel biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups were synthesized via the macromolecular substitution reactions of poly(dichlorophosphazene) with the sodium salt of lactic acid ester and sodium methoxyethoxyethoxide.Their structures were confirmed by ~(31)p NMR,~1H NMR,~(13)C NMR,IR,DSC,and elemental analysis.The lower critical solution temperature(LCST) behavior in water and in vitro degradation property of the polymers was investigated.The results indicated that two polymers showed LCST phase transition over a range of concentrations from 0.13 to 15 wt%and pH-sensitive degradation properties. Two novel biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups were synthesized via the macromolecular substitution reactions of poly (dichlorophosphazene) with the sodium salt of lactic acid ester and sodium methoxyethoxyethoxide. Their structures were confirmed by ~ (31) p NMR, ~ 1H NMR, ~ (13) C NMR, IR, DSC, and elemental analysis. Lower solution temperature (LCST) behavior in water and in vitro degradation property of the polymers was investigated. The results indicated that two polymers showed LCST phase transition over a range of concentrations from 0.13 to 15 wt% and pH-sensitive degradation properties.
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