The novel quaternized hydroxypropyl cellulose-g-poly(THF-co-epichlorohydrin)graft copolymers,HPC-g-QCP(THF-co-ECH),have been successfully synthesized to combine the properties from hydrophilic hard HPC biomacromolecul...The novel quaternized hydroxypropyl cellulose-g-poly(THF-co-epichlorohydrin)graft copolymers,HPC-g-QCP(THF-co-ECH),have been successfully synthesized to combine the properties from hydrophilic hard HPC biomacromolecular backbone and hydrophobic flexible polyether branches.Firstly,the P(THF-co-ECH)living chains were synthesized by cationic ring-opening copolymerization of THF with ECH.Secondly,P(THF-co-ECH)living chains were grafted onto HPC backbone by reaction with-OH groups along HPC to produce HPC-g-P(THF-co-ECH)graft copolymers.Thirdly,the mentioned graft copolymers were quaternized by reaction with ternanyamine to generate functionalized HPC-g-QCP(THF-co-ECH).The HPC-g-QCP(THF-co-ECH)graft copolymers exhibited good antibacterial ability against S.aureus or E.coli bacteria.The ibuprofen(IBU)-loaded microparticles of HPC-g-(QC)P(THF-co-ECH)graft copolymers were prepared by electrospraying.The in vitro pH-responsive drug-release behavior of IBU reached up to 75%of drug-loaded at pH=7A.This quaternized graft copolymer was beneficial to solving the problems of a burst effect and fast release of HPC as drug carriers.展开更多
The novel amphiphilic graft copolymers with hydrophilic hard polar hydroxypropyl cellulose(HPC)backbone and hydrophobic soft nonpolar polyisobutylene(PIB)branches have been successfully synthesized through nucleophili...The novel amphiphilic graft copolymers with hydrophilic hard polar hydroxypropyl cellulose(HPC)backbone and hydrophobic soft nonpolar polyisobutylene(PIB)branches have been successfully synthesized through nucleophilic substitution reaction of living PIB chains carrying oxonium ions with the-OH groups along HPC backbone.The PIB branch length in the graft copolymers could be designed by living cationic polymerization and the grafting density could be adjusted by PIB+/-OH molar ratio.The living PIB chains carrying oxonium ion were prepared by transformation of allyl bromide end groups in the presence of AgCI0_(4) and silver nanoparticles(3.2±0.3 nm,0.7 wt%-1.8 wt%)generated in situ from AgBr.The phase-separation morphology was formed in the graft copolymers due to their incompatibility between backbone and branches.The hydrophilicity on the surface of graft copolymer films could be turned to hydrophobicity by increasing grafting density or/and length of PIB branches.The soft PIB segments in graft copolymers provided an unique surface wa self-assembly for ant卜protein adsorption against bovine serum albumin.A small amount of Ag nanoparticles in the copolymers contributed to good antibacterial activities against Staphylococcus aureus or Escherichia coli.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Nos.21574007 and 51521062).
文摘The novel quaternized hydroxypropyl cellulose-g-poly(THF-co-epichlorohydrin)graft copolymers,HPC-g-QCP(THF-co-ECH),have been successfully synthesized to combine the properties from hydrophilic hard HPC biomacromolecular backbone and hydrophobic flexible polyether branches.Firstly,the P(THF-co-ECH)living chains were synthesized by cationic ring-opening copolymerization of THF with ECH.Secondly,P(THF-co-ECH)living chains were grafted onto HPC backbone by reaction with-OH groups along HPC to produce HPC-g-P(THF-co-ECH)graft copolymers.Thirdly,the mentioned graft copolymers were quaternized by reaction with ternanyamine to generate functionalized HPC-g-QCP(THF-co-ECH).The HPC-g-QCP(THF-co-ECH)graft copolymers exhibited good antibacterial ability against S.aureus or E.coli bacteria.The ibuprofen(IBU)-loaded microparticles of HPC-g-(QC)P(THF-co-ECH)graft copolymers were prepared by electrospraying.The in vitro pH-responsive drug-release behavior of IBU reached up to 75%of drug-loaded at pH=7A.This quaternized graft copolymer was beneficial to solving the problems of a burst effect and fast release of HPC as drug carriers.
基金the National Natural Science Foundation of China(Nos.21574007 and 51521062)the Fundamental Research Funds for the Central Universities(Nos.XK1802-2 and XK1802-1).
文摘The novel amphiphilic graft copolymers with hydrophilic hard polar hydroxypropyl cellulose(HPC)backbone and hydrophobic soft nonpolar polyisobutylene(PIB)branches have been successfully synthesized through nucleophilic substitution reaction of living PIB chains carrying oxonium ions with the-OH groups along HPC backbone.The PIB branch length in the graft copolymers could be designed by living cationic polymerization and the grafting density could be adjusted by PIB+/-OH molar ratio.The living PIB chains carrying oxonium ion were prepared by transformation of allyl bromide end groups in the presence of AgCI0_(4) and silver nanoparticles(3.2±0.3 nm,0.7 wt%-1.8 wt%)generated in situ from AgBr.The phase-separation morphology was formed in the graft copolymers due to their incompatibility between backbone and branches.The hydrophilicity on the surface of graft copolymer films could be turned to hydrophobicity by increasing grafting density or/and length of PIB branches.The soft PIB segments in graft copolymers provided an unique surface wa self-assembly for ant卜protein adsorption against bovine serum albumin.A small amount of Ag nanoparticles in the copolymers contributed to good antibacterial activities against Staphylococcus aureus or Escherichia coli.
