中文摘要：

采用可控开环聚合（ROP）和原子转移自由基聚合（ATRP）相结合的方法制备出一系列单甲氧基聚乙二醇-b-聚（ε-己内酯）-b-聚甲基丙烯酸-N,N-二甲氨基乙酯（MePEG-b-PCL-b-PDMAEMA）.采用核磁（1H NMR）和凝胶渗透色谱（GPC）研究了聚合物的结构并对聚合物的分子量大小和分布进行了表征.聚合物的热稳定性能、结晶性能和亲水性能分别由热重分析仪（TGA）、X-衍射仪（XRD）和静态水滴接触角测定.分别采用荧光光谱法和1H NMR（以D2O为溶剂）方法研究了聚合物纳米粒子的形成.激光光散射（DLS）和透射电镜（TEM）研究结果表明聚合物纳米粒子具有球形结构,粒子大小在40～70 nm之间并且对外界环境具有pH敏感性能.MePEG-b-PCL-b-PDMAEMA纳米粒子在同时包裹带有正电荷药物以及疏水性药物方面具有潜在的应用前景.

英文摘要：

A series of well-controlled triblock methoxy poly（ethylene glycol）-b-poly（ε-caprolactone）-b-poly[2-（dimethylamino） ethyl methacrylate]（MePEG-b-PCL-b-PDMAEMA） was obtained by ring open polymerization（ROP） and atom transfer radical polymerization（ATRP） methods.Their structures and composition were confirmed by 1H nuclear magnetic resonance（1H NMR）,and the molecule weight and molecular weight distribution of the copolymers were obtained by 1H NMR and gel permeation chromatog-raphy（GPC）.The thermal stability,crystallization property and hydrophiphilicity were evidenced by thermogravimetric analysis,X-ray diffraction（XRD） and static water contact angle measurements.The formation of the nanoparticles was studied by 1H NMR in D2O and fluorescence probe method.The transmission electron microscopy（TEM） displayed that the morphologies of the nanoparticles were spherical and the size was on nano scale.Dynamic light scattering（DLS） indicated that the nanoparticles were in the range of 40～ 70 nm,and in different pH solution,the nanoparticles showed good pH-sensitivity.Due to the hydrophobic core and the cationic hydrophilic shell,the nanoparticles has great potential application for the codelivery of hydrophobic drugs and negative drugs.