The monodispersed latex particles were prepared by soap-free emulsion copolymerization of styrene(St) with hydroxyethyl methacrylate(HEMA). The nucleation mechanism and growth process of polymer latex particles were i...The monodispersed latex particles were prepared by soap-free emulsion copolymerization of styrene(St) with hydroxyethyl methacrylate(HEMA). The nucleation mechanism and growth process of polymer latex particles were investigated. The effects of HEMA on diameter of the latex particles and monomer conversion were discussed. The elemental analysis and XRD results showed that HEMA was dispersed mainly on the surface of the latex particles, it could stabilize the latex particles and lead the nucleation. The nucleation of particles occurs likely by homogeneous nucleation mechanism. The diameter of the latex particles decreased and the conversion increased, as HEMA′s dosage increased.展开更多
通过开环聚合(ROP)、DCC偶合反应及原子转移自由基聚合(ATRP)合成3种不同臂数(线性、三臂和六臂)的聚己内酯-b-聚乙二醇-b-聚甲基丙烯酸(2-羟乙酯)(PCL-PEG-PHEMA)三嵌段共聚物。通过核磁氢谱(1 H NMR)红外谱图证明合成了设计产物。以...通过开环聚合(ROP)、DCC偶合反应及原子转移自由基聚合(ATRP)合成3种不同臂数(线性、三臂和六臂)的聚己内酯-b-聚乙二醇-b-聚甲基丙烯酸(2-羟乙酯)(PCL-PEG-PHEMA)三嵌段共聚物。通过核磁氢谱(1 H NMR)红外谱图证明合成了设计产物。以溶剂挥发法制备胶束并进行载药实验。用激光粒度仪测定胶束粒径、粒径分布及zeta电位,用荧光光谱仪以芘荧光探针法测定临界胶束浓度,用紫外-可见分光光度计表征胶束载药量、包封率。结果表明,3种三嵌段共聚物均能形成稳定的载药胶束,其中具有星形结构的六臂的三嵌段共聚物具有最低的胶束粒径和临界胶束浓度、最高的载药量和包封率。因此,星形六臂的PCL-PEG-PHEMA可作为新的药物载体材料。展开更多
文摘The monodispersed latex particles were prepared by soap-free emulsion copolymerization of styrene(St) with hydroxyethyl methacrylate(HEMA). The nucleation mechanism and growth process of polymer latex particles were investigated. The effects of HEMA on diameter of the latex particles and monomer conversion were discussed. The elemental analysis and XRD results showed that HEMA was dispersed mainly on the surface of the latex particles, it could stabilize the latex particles and lead the nucleation. The nucleation of particles occurs likely by homogeneous nucleation mechanism. The diameter of the latex particles decreased and the conversion increased, as HEMA′s dosage increased.
文摘通过开环聚合(ROP)、DCC偶合反应及原子转移自由基聚合(ATRP)合成3种不同臂数(线性、三臂和六臂)的聚己内酯-b-聚乙二醇-b-聚甲基丙烯酸(2-羟乙酯)(PCL-PEG-PHEMA)三嵌段共聚物。通过核磁氢谱(1 H NMR)红外谱图证明合成了设计产物。以溶剂挥发法制备胶束并进行载药实验。用激光粒度仪测定胶束粒径、粒径分布及zeta电位,用荧光光谱仪以芘荧光探针法测定临界胶束浓度,用紫外-可见分光光度计表征胶束载药量、包封率。结果表明,3种三嵌段共聚物均能形成稳定的载药胶束,其中具有星形结构的六臂的三嵌段共聚物具有最低的胶束粒径和临界胶束浓度、最高的载药量和包封率。因此,星形六臂的PCL-PEG-PHEMA可作为新的药物载体材料。
