Multicomponent Block Copolymers as Precursors to Functional Nanoporous Materials

技术概述：嵌段共聚物是含有多个共价连接的聚合物链段的混合大分子。这些材料在纳米尺度上自组装，并可以采用各种有序的形态。对于AB二嵌段共聚物，在B组分的基质中的A组分的六方填充的纳米级圆柱体是通常观察到的形态。对于ABC三嵌段三元共聚物，在C组分的基质中具有由B组分的壳包围的A组分的圆柱体的形态是普遍的。在这两种情况下，A组分的选择性化学蚀刻将导致具有由牺牲组分模板化的通道的纳米多孔材料。使用脂肪族聚酯和聚醚作为可降解组分合成纳米多孔材料的这种方法是该项目的核心。旨在提高有序嵌段共聚物的纳米多孔材料的机械完整性的方法将被探索。这些包括高度缠结、半结晶或热塑性弹性体的基体聚合物的设计和开发。这些努力将大大扩展对纳米多孔塑料机械性能的理解，并为这些材料的未来应用提供基础。此外，嵌段共聚物衍生的纳米多孔材料作为多相催化的高表面积载体的使用将被检查。这些基板的可调性质是特别值得注意的，并将使这些材料如何作为载体催化剂的介质和这些材料作为实际的催化剂载体的发展的详细了解。纳米粒子，简单的有机催化剂和更复杂的肽为基础的催化，和酶的支持版本将探索各种催化和不对称transformation.NON-TECHNICAL摘要：多孔材料已发现在非常广泛的技术应用的实用程序。这些普遍存在的有机和无机材料在商业上是重要的，例如，作为石油化学工业中的催化剂、生物技术的分离介质和微电子学的层间填料。本工作的主要目标是设计、合成和开发新类型的聚合物（即，塑料）纳米多孔材料（具有纳米尺寸孔的多孔材料），具有广泛的、可调的特性。这项工作的动机是先进的纳米技术的应用，并将重点揭示与这些新材料的化学和物理性质的合成和最终调整相关的基本原理。本提案中开发的材料最终将通过分离应用（例如，水净化）和催化（即，绿色化学）。已经报道了用于这些目的的纳米多孔材料的使用，并且这项研究将直接影响嵌段共聚物在这些应用中的效用。广泛的聚合物科学培训的研究人员在这个项目上工作也将导致，和具体的战略，旨在沟通基础研究的重要性，本科生和公众将实施。

TECHNICAL SUMMARY:Block copolymers are hybrid macromolecules that contain multiple, covalently connected polymer segments. These materials self-assemble on nanometer length scales and can adopt a variety of ordered morphologies. For AB diblock copolymers, hexagonally packed, nanoscopic cylinders of the A component in a matrix of the B component is a commonly observed morphology. For ABC triblock terpolymers, a morphology with cylinders of the A component, surrounded by a shell of the B component, in a matrix of the C component is prevalent. Selective chemical etching of the A component in both of the cases will lead to nanoporous materials with channels templated by the sacrificial component. This approach to the synthesis of nanoporous materials using aliphatic polyesters and polyethers as the degradable components is central to this project. Methods aimed at enhancing the mechanical integrity of nanoporous materials from ordered block copolymers will be explored. These include the design and development of matrix polymers that are either highly entangled, semi-crystalline, or thermoplastic elastomers. These efforts will significantly expand understanding of mechanical properties in nanoporous plastics and provide the basis for future applications of these materials. In addition, the use of block copolymer-derived nanoporous materials as high surface area supports for heterogeneous catalysis will be examined. The tunable nature of these substrates is particularly noteworthy and will enable both a detailed understanding of how these materials behave as media for supported catalysts and development of these materials as practical catalyst supports. Supported versions of nanoparticles, simple organocatalysts and more complex peptide based catalysis, and enzymes will be explored for a variety of catalytic and asymmetric transformations.NON-TECHNICAL SUMMARY:Porous materials have found utility in an extremely wide range of technological applications. These ubiquitous organic and inorganic materials are commercially important as, for example, catalysts in the petrochemical industry, separation media for biotechnology, and interlayer dielectrics for microelectronics. The principal objective of this work is to design, synthesize and develop new classes of polymeric (i.e., plastic) nanoporous materials (porous materials with nanometer sized pores) with wide-ranging, tunable properties. This work is motivated by advanced nanotechnological applications and will focus on uncovering fundamental principles associated with the synthesis and ultimate tuning of the chemical and physical properties of these novel materials. Materials developed in this proposal will ultimately lead to societal benefit through applications in separations (e.g., water purification) and catalysis (i.e., Green Chemistry). The use of nanoporous materials for these purposes has been reported, and this research will directly impact the utility of block copolymers in these applications. Broad polymer science training of the researchers working on this project will also result, and specific strategies aimed at communicating the importance of basic research to both undergraduate students and the public will be implemented.