【作者】 霍浩辉； 张启路； 刘峰；

【Author】 Haohui Huo;Qilu Zhang;Feng Liu;State Key Laboratory for Mechanical Behavior of Materials,Xi’an Jiaotong University;

【机构】 西安交通大学金属材料强度国家重点实验室；

【摘要】 目前单链偶联聚合物纳米粒子(SCTNPs)的制备主要是通过嵌段共聚物分子内交联的方法,然而该方法不仅需要复杂的合成设计,而且还要求聚合物的浓度低于其缠结浓度。因此,高浓度下大规模制备单链偶联聚合物纳米粒子一直是一个巨大的挑战。正如理论模型和实验结果所证实,多臂星形聚合物可被视为刚硬的球形纳米粒子。基于此,本报告提出了一种通用的、可扩展的制备尺寸和柔软度可调的单链偶联聚合物纳米粒子的方法。通过连续的点击化学和可控自由基聚合,合成了一系列含有一条较长的PEG链和二十条较短的Pt BA臂的星形聚合物,表示为PEG-b-(Pt BA)20。TEM表征证实了该类星形聚合物在溶液中表现为球形结构。结合该星形聚合的构象特征,我们称之为单链偶联海胆型纳米粒子(SCTSUNPs)。进一步研究SCTSUNPs的自组装行为,发现随着SCTSUNPs中Pt BA链长的增加其可以在水溶液中自组装形成环形纳米结构、双连续蠕虫结构、互相交错的囊泡以及双层囊泡结构。SCTSUNPs可调节的变形性被认为是诱导形成这些有趣结构,如环形纳米结构和互相交错囊泡的主要原因。更多还原

【Abstract】 The synthesis of single-chain tethered nanoparticles(SCTNPs) is mostly based on the intramolecular cross-linking of the block copolymer. However, complex synthetic design and dilute polymer solution are crucial for this method. Scalable synthesis of SCTNPs at high concentration is still a challenge. Herein, a general and scalable strategy for the preparation of single-chain tethered nanoparticles(SCTNPs) with tunable size and softness is reported. The SCTNPs composing of a poly(ethylene glycol)(PEG) chain anchored on a star polymer with 20 poly(tert-butyl acrylate)(Pt BA) arms were synthesized by successive click coupling reaction and controlled radical polymerization at high concentrations, enabling large scale preparation. As predicted by theoretical modeling, the 20-arm star polymer can be considered as spherical NP with tunable size and softness, which has been confirmed by TEM characterization in this research. Hence the obtained systems are named as single-chain tethered sea urchin-like nanoparticle(SCTSUNP). Toroidal nanostructures, bicontinuous worms and spherical micelles, interdigitated vesicles, and bilayer vesicles were successively observed by TEM with the increasing of the arm length. The low deformability of the sea urchin-like nanoparticles is believed to be the key factor that determines the formation of the special nanostructures, e.g. toroid and interdigitated vesicles.更多还原