Some methods have been developed to use CO2 as the raw material to produce degradable polymeric materials.The terpolymer of carbonate（PPGC） synthesized with the terpolymerization of CO2,propylene oxide and γ-butyro...Some methods have been developed to use CO2 as the raw material to produce degradable polymeric materials.The terpolymer of carbonate（PPGC） synthesized with the terpolymerization of CO2,propylene oxide and γ-butyrolactone（GBL）.GBL offered an ester structural unit making the copolymer easier to hydrolyze.Hence, PPCG should be of good degradability.In order to study its degradability,the polymer PPCG was used as materials for drag loading.The drug-loaded microspheres were obtained by the W/O/W type emulsions method. The microspheres were spherical in shape with smooth surfaces and good dispersion. The drug loading and encapsulation efficiency were 36.7% and 78.6%, respectively. The degradative behave was studied by SEM, XRD and drug release curves in different degradation medium were obtained.It was found that these microspheres could be degraded at faster speed in the basic media, while could not be degraded in the acidic media.The higher pH value of the medium was,the faster the initial degradative speed was.展开更多
文摘Some methods have been developed to use CO2 as the raw material to produce degradable polymeric materials.The terpolymer of carbonate（PPGC） synthesized with the terpolymerization of CO2,propylene oxide and γ-butyrolactone（GBL）.GBL offered an ester structural unit making the copolymer easier to hydrolyze.Hence, PPCG should be of good degradability.In order to study its degradability,the polymer PPCG was used as materials for drag loading.The drug-loaded microspheres were obtained by the W/O/W type emulsions method. The microspheres were spherical in shape with smooth surfaces and good dispersion. The drug loading and encapsulation efficiency were 36.7% and 78.6%, respectively. The degradative behave was studied by SEM, XRD and drug release curves in different degradation medium were obtained.It was found that these microspheres could be degraded at faster speed in the basic media, while could not be degraded in the acidic media.The higher pH value of the medium was,the faster the initial degradative speed was.
