Polypeptoids as model materials for studying the role of monomer sequence and chain shape on block copolymer self-assembly

类多肽作为研究单体序列和链形状对嵌段共聚物自组装作用的模型材料

• 批准号: 1608297
• 负责人: Rachel Segalman
• 金额: $ 39.14万
• 依托单位: University of California-Santa Barbara
• 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: 2016-05-01 至 2022-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1608297&HistoricalAwards=false
• 关键词: Polypeptoids; model; materials; studying; role

PART 1: NON-TECHNICAL SUMMARYPolymers that form patterns on the nanometer scale are important components of adhesives and next-generation flexible and rubbery materials. Being able to control this patterning in next-generation polymers is important for applications such as nanolithography, flexible electronics, and biomedicine. These polymers have much more complicated chemical structures and molecular-scale shapes than typical polymer molecules. This project is targeted at understanding how complexity in the molecule's chemical structure and shape affects its ability to form patterns involving the mutual packing of many molecules. To do this, molecules will be designed and studied that are inspired by biological polymers (proteins) but allow for tuning of their shape, stiffness, and chemical structure. Undergraduate and graduate student researchers will be trained at national research user-facilities, participate in local and national scientific meetings, and interact closely with research collaborators. Combining both research and learning to interact in the broader scientific community comprises an integral part of the educational experience for graduate students bound for either industrial careers or the academic world. Furthermore, the PI will partner with the UCSB Center for Science and Engineering Partnerships to incorporate a diverse cadre of incoming community-college transfer students into the research group to both ease transfer shock and provide research experience. A robust program of "Science Night" outreach activities at Santa Barbara/Goleta elementary and middle schools will continue to generate excitement in STEM fields among a new generation of students. PART 2: TECHNICAL SUMMARYEquilibrium self-assembled mesostructures in block copolymers arise from the competition between enthalpic segregation of dissimilar blocks, liquid crystalline interactions, composition, and the mismatch in scaling dimensions between blocks. The ability to synthesize sequence-specific polypeptoids at gram scale presents a unique opportunity to directly test predictions of copolymer self-assembly that suggest both 'blockiness' and gradient strength in a copolymer sequence impacts the chain's ability to minimize free energy by sorting monomers to the preferred side of the interface. Furthermore, the chain persistence length is tunable on a single chemical platform by controlling the sequence, side chain chirality, and bulkiness. This platform provides the conformational (persistence length) control necessary to explore the continuum of semiflexible chain shapes between the rod and coil limits. In addition, the fundamental role of asymmetry in contributing long-range entropic effects to the free energy of mixing will be explored. The goal of this project is to develop a deep understanding of how sequence and chain shape impact the free energy contributions to block copolymer self-assembly. It is expected that this fundamental understanding will guide the design of semiflexible and sequence-defined block copolymers and ultimately impact fields as diverse as organic optoelectronics and biomaterials.

第一部分： 非技术概述在纳米尺度上形成图案的聚合物是粘合剂和下一代柔性和橡胶材料的重要组分。 能够在下一代聚合物中控制这种图案化对于纳米光刻、柔性电子和生物医学等应用非常重要。这些聚合物具有比典型聚合物分子复杂得多的化学结构和分子尺度形状。该项目旨在了解分子化学结构和形状的复杂性如何影响其形成涉及许多分子相互包装的模式的能力。 为了做到这一点，将设计和研究受生物聚合物（蛋白质）启发的分子，但允许调整它们的形状，刚度和化学结构。 本科生和研究生研究人员将在国家研究用户设施接受培训，参加地方和国家科学会议，并与研究合作者密切互动。结合研究和学习，在更广泛的科学界进行互动，是研究生教育经验的一个组成部分，无论是工业职业还是学术界。此外，PI将与UCSB科学与工程合作中心合作，将一批来自社区学院的转学生纳入研究小组，以缓解转学冲击并提供研究经验。 圣巴巴拉/戈莱塔小学和中学的“科学之夜”外联活动将继续在新一代学生中引起STEM领域的兴奋。第二部分： 技术概述嵌段共聚物中的平衡自组装介观结构由不同嵌段的结晶分离、液晶相互作用、组成和嵌段之间尺度尺寸的失配之间的竞争产生。以克级合成序列特异性多肽的能力提供了一个独特的机会来直接测试共聚物自组装的预测，这表明共聚物序列中的“嵌段性”和梯度强度影响链通过将单体分选到界面的优选侧来最小化自由能的能力。 此外，通过控制序列、侧链手性和体积，可以在单个化学平台上调节链持续长度。 这个平台提供了必要的构象（持久长度）控制，探索杆和线圈限制之间的半柔性链形状的连续体。此外，不对称性的基本作用，在长期的熵效应的混合自由能将被探讨。 这个项目的目标是深入了解序列和链形状如何影响嵌段共聚物自组装的自由能贡献。预计这种基本的理解将指导半柔性和序列定义的嵌段共聚物的设计，并最终影响有机光电子和生物材料等不同领域。

项目成果

Thermal Control of Confined Crystallization within P3EHT Block Copolymer Microdomains

P3EHT 嵌段共聚物微域内限制结晶的热控制

• DOI: 10.1021/acs.macromol.7b01616
• 发表时间: 2017
• 期刊: Macromolecules
• 影响因子: 5.5
• 作者: Davidson, Emily C.;Segalman, Rachel A.
• 通讯作者: Segalman, Rachel A.

Impact of Helical Chain Shape in Sequence-Defined Polymers on Polypeptoid Block Copolymer Self-Assembly

• DOI: 10.1021/acs.macromol.8b00055
• 发表时间: 2018-03-13
• 期刊: MACROMOLECULES
• 影响因子: 5.5
• 作者: Davidson, Emily C.;Rosales, Adrianne M.;Segalman, Rachel A.
• 通讯作者: Segalman, Rachel A.

Confined Crystallization within Cylindrical P3EHT Block Copolymer Microdomains

圆柱形 P3EHT 嵌段共聚物微域内的限域结晶

• DOI: 10.1021/acs.macromol.7b01323
• 发表时间: 2017
• 期刊: Macromolecules
• 影响因子: 5.5
• 作者: Davidson, Emily C.;Segalman, Rachel A.
• 通讯作者: Segalman, Rachel A.

Mixed Conductive Soft Solids by Electrostatically Driven Network Formation of a Conjugated Polyelectrolyte

• DOI: 10.1021/acs.chemmater.7b05303
• 发表时间: 2018-02-27
• 期刊: CHEMISTRY OF MATERIALS
• 影响因子: 8.6
• 作者: Danielsen, Scott P. O.;Sanoja, Gabriel E.;Segalman, Rachel A.
• 通讯作者: Segalman, Rachel A.