'Patchy' Nanoparticles from Bottle-brush Polymers

来自瓶刷聚合物的“片状”纳米颗粒

• 批准号: 1562639
• 负责人: Margarita Herrera-Alonso
• 金额: $ 30万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-04-01 至 2019-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1562639&HistoricalAwards=false
• 关键词: Patchy; Nanoparticles; Bottle; brush; Polymers

Particles with surface heterogeneity or surface 'patchiness' are of general interest as building-blocks for the construction of hierarchical nanosystems. Of these, polymer-based nanoparticles are particularly attractive for their softer, more dynamic character, facilitating the construction process. Surface pattering of polymer particles at the nanometer scale, while challenging, can be accomplished through the use of assembling subunits with a molecular architecture that will lead to a 'clustering' effect. This award allows the exploration of the use of polymers with a bottle-brush architecture as subunits for the formation of 'patchy' nanoparticles. Unlike the more traditional linear polymers, considerably less is known about the assembly behavior of polymers with a complex architecture, opening new routes for the formation of polymer-based nanomaterials with unique functions. The research will examine solution self- and co-assembly of these polymers and establish relationships between polymer architecture, processing routes and aggregate morphology. Outreach efforts supported under this award will involve participation of undergraduate students in research, and community involvement through an education-based Latino outreach program targeting K-12 students. The overarching goal of this award is to explore the molecular and processing determinants of assemblies from highly grafted polymers, with particular emphasis on the construction of nanoparticles exhibiting surface and core heterogeneity. Advances in controlled polymerization methods have enabled the synthesis of macromolecules with increasing functional and architectural complexity such as macromolecular brushes or bottle-brushes. In contrast to linear diblock copolymers, little is known about the factors that influence solution assembly of macromolecules. Furthermore, it has been previously shown that kinetic pathways of polymer assembly are determining factors of assembly morphologies from linear block copolymers, whereas the non-equilibrium behavior of macromolecules with more complex architectures remains unexplored. This award addresses two related objectives. First objective is to study nanoparticle formation from amphiphilic macromolecular brush copolymers by a rapid assembly process. This will allow to both elucidate the mechanism of brush copolymer assembly into multi-molecular nanoparticles, and determine absolute timescales of assembly. Second objective is to study the formation of complex heterogeneous nanosystems from amphiphilic macromolecular brush building-blocks. This involves co-assembly of families of macromolecular brushes with varying degrees of chemical dissimilarity through kinetic trapping. While there are many reported methods for fabricating composite nanoparticles exhibiting surface and/or core heterogeneity, clustering of relatively soft and adaptive building-blocks could provide the means for further intra-particle modifications.

表面异质性或表面“斑块”的颗粒作为构建层次纳米系统的建筑构造的普遍兴趣。其中，基于聚合物的纳米颗粒对其柔和，更具动态的特征特别有吸引力，从而促进了施工过程。在纳米尺度上，聚合物颗粒的表面模式可以通过将亚基与分子结构的组装来实现，从而实现了“聚类”效果。该奖项允许探索将聚合物与瓶刷结构用作形成“斑点”纳米颗粒的亚基的使用。与更传统的线性聚合物不同，对聚合物具有复杂体系结构的组装行为的了解要少得多，这为形成具有独特功能的基于聚合物的纳米材料的新途径。该研究将检查这些聚合物的自我组装和共同组装，并在聚合物结构，加工途径和汇总形态之间建立关系。该奖项支持的外展工作将涉及本科生参与研究，并通过针对K-12学生的基于教育的拉丁裔外展计划参与社区参与。该奖项的总体目标是探索来自高度移植聚合物的组装的分子和加工决定因素，特别强调纳米颗粒表现出表面和核心异质性。受控聚合方法的进步已使大分子的合成具有增加功能和建筑复杂性，例如大分子刷子或瓶刷。与线性二嵌段共聚物相反，对影响大分子溶液组装的因素知之甚少。此外，先前已经证明，聚合物组装的动力学途径正在确定线性块共聚物的组装形态因素，而具有更复杂体系结构的大分子的非平衡行为仍未得到解释。该奖项针对两个相关目标。第一个目的是通过快速组装过程研究来自两亲性大分子分子刷共聚物的纳米颗粒形成。这将允许阐明刷子共聚物组件的机理到多分子纳米颗粒中，并确定组装的绝对时间尺度。第二个目标是研究由两亲性大分子刷子建筑块形成复杂的异质纳米系统。这涉及通过动力学诱捕的大分子刷子的共同组装，化学差异不同。尽管有许多报道的方法用于制造表面表面和/或核心异质性的复合纳米颗粒，但相对柔软和适应性建筑块的聚类可以为进一步的粒子内修饰提供手段。