Polymeric micelles were prepared by dropping ethanol into solutions containing（poly（γ-benzyl L-）glutamate）-poly（ethylene oxide） block copolymer （PBLG-b-PEO）,chloroform（CHCl3） and trifluoroacetic acid（TFA）...Polymeric micelles were prepared by dropping ethanol into solutions containing（poly（γ-benzyl L-）glutamate）-poly（ethylene oxide） block copolymer （PBLG-b-PEO）,chloroform（CHCl3） and trifluoroacetic acid（TFA）.Viscometry,transmission electron microscopy（TEM）,nuclear magnetic resonance（（）1H-NMR） spectroscopy and infra-red difference spectroscopy（IR） were used to investigate the influence of PBLG chain conformation on the self-assembly behavior of PBLG-b-PEO.The experimental results revealed that PBLG-b-PEO could associate into polymeric micelles in ethanol solutions.The introduction of TFA not only changes the conformation of PBLG segments,but also increases the critical micelle concentration,and further affects the morphologies of the formed micelles.展开更多
Polypeptide graft copolymers such as poly(γ-benzyl-L-glutamate)(PBLG)-poly(ethylene glycol)(PEG) and poly(γ-ethyl-L-glutamate)(PELG)-poly(ethylene glycol)(PEG) were introduced into self-setting calcium phosphate cem...Polypeptide graft copolymers such as poly(γ-benzyl-L-glutamate)(PBLG)-poly(ethylene glycol)(PEG) and poly(γ-ethyl-L-glutamate)(PELG)-poly(ethylene glycol)(PEG) were introduced into self-setting calcium phosphate cement(CPC) system to improve its mechanical properties. The compression strength was improved considerably by the induction of polypeptide copolymers. It is about 22.3 higher for PBLG-g-PEG and 65.0 higher for PELG-g-PEG, respectively. The results also show that for the same polypeptide copolymer, higher compression strength of composites can be obtained by introducing copolymer micelles into the CPC. According to the results of scanning electron microscope(SEM), the crystallite shapes of CPC depend on the weight fraction of polypeptide copolymer in the composites.展开更多
文摘Polymeric micelles were prepared by dropping ethanol into solutions containing（poly（γ-benzyl L-）glutamate）-poly（ethylene oxide） block copolymer （PBLG-b-PEO）,chloroform（CHCl3） and trifluoroacetic acid（TFA）.Viscometry,transmission electron microscopy（TEM）,nuclear magnetic resonance（（）1H-NMR） spectroscopy and infra-red difference spectroscopy（IR） were used to investigate the influence of PBLG chain conformation on the self-assembly behavior of PBLG-b-PEO.The experimental results revealed that PBLG-b-PEO could associate into polymeric micelles in ethanol solutions.The introduction of TFA not only changes the conformation of PBLG segments,but also increases the critical micelle concentration,and further affects the morphologies of the formed micelles.
文摘Polypeptide graft copolymers such as poly(γ-benzyl-L-glutamate)(PBLG)-poly(ethylene glycol)(PEG) and poly(γ-ethyl-L-glutamate)(PELG)-poly(ethylene glycol)(PEG) were introduced into self-setting calcium phosphate cement(CPC) system to improve its mechanical properties. The compression strength was improved considerably by the induction of polypeptide copolymers. It is about 22.3 higher for PBLG-g-PEG and 65.0 higher for PELG-g-PEG, respectively. The results also show that for the same polypeptide copolymer, higher compression strength of composites can be obtained by introducing copolymer micelles into the CPC. According to the results of scanning electron microscope(SEM), the crystallite shapes of CPC depend on the weight fraction of polypeptide copolymer in the composites.
