Mixed Rod-Coil Polymer Brushes Tailored for Controlled Surface Topography

专为受控表面形貌而定制的混合棒线圈聚合物刷

• 批准号: 1905403
• 负责人: Yu Zhong
• 金额: $ 75万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1905403&HistoricalAwards=false
• 关键词: Mixed; Rod; Coil; Polymer; Brushes

PART 1: NON-TECHNICAL SUMMARY: Polymers are long molecules that make up the many kinds of coatings, fabrics and plastics we use. Some polymers can be flexible and soft. Other polymers can be long and stiff. By combining stiff and flexible polymers in a single system formed on a surface, we have learned that we can make nanoscale spiky brush-like surfaces using careful temperature control and coating methods. The PI and his group plan to better understand this surface formation process by making new combinations of soft and stiff polymers, by using advanced tools to study their organization, and by employing computers to model the structure and to predict their behavior. This new way of making surfaces opens up many interesting applications. For example, the surface mimics the protein spikes present on virus surfaces that are used by nature to identify target cells, take part in the entry into the cell, and also to prevent identification by antibodies. These materials can be used to study the behavior of cells on topics ranging from how they work to the behavior of the immune system. Because the spikes are vertically aligned, they may also act as nanowires, so they can be used in energy production and storage systems like solar cells and batteries. Finally, these spikes may be piezoelectric, i.e. they could convert electrical energy to motion (or sound) and motion to electrical energy. This research program will also serve as a mechanism to teach students about polymers and materials science, create globally aware graduate students, and expose students to a collaborative environment. Graduate students will be able to work with the research groups of our collaborators as parts of teams and to take part in exchange visits. Lessons learned from these research programs will be used to teach K-12 students and to be applied in high school teachers' workshops. PART 2: TECHNICAL SUMMARY:Coil polymer brushes synthesized using living radical polymerization methods will be combined with rod brushes with high persistence lengths grown from surfaces made using a variety of living and pseudo-living chemistries. Phase separation aided by solvent processing and guided by nanolithography will be used to control in-plane structure. A variety of chemical and process methods will be used to limit macroscopic phase separation and thereby direct assembly of topographical and chemical structures. Brush growth will employ new, chemically tailored brush initiators for single chain and binary chain growth to form rod-coil mixed brush pairings. To direct brush structure and rod-coil phase separation, brush initiators will be patterned at length scales of a few 10s of nanometers using state-of-the-art lithography methods to control spacing of the brush spikes. Brush organization will be compared to computational predictions which will be used to guide both brush design and selection and to anticipate the resulting physical structure and aid characterization studies. Characterization of the brushes will be made using a selection of analytical methods including grazing incidence (GI) SAXS and WAXS, neutron reflectivity and resonant soft X-ray scattering (RSoXS) measurements. Studies of the conductivity and piezoelectric character of the rod-coil brush films will aid in our understanding of the mixed brush structure. Through collaborations, studies of these materials as cell membrane substrates, for targeted biomolecular binding, as piezoelectric and as conducting materials with unusual transport pathways, will also provide information about key length scales and rod-brush organization. .This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

第1部分：非技术摘要：聚合物是构成我们使用多种涂料，织物和塑料的长分子。一些聚合物可以柔软且柔软。其他聚合物可以长而僵硬。通过在形成表面上形成的单个系统中结合僵硬和柔性的聚合物，我们了解到可以使用仔细的温度控制和涂料方法使纳米级尖峰刷状表面形成。 PI及其小组计划通过使用先进的工具来研究其组织，并使用计算机来建模并预测其行为，从而通过制作软性和僵硬聚合物的新组合来更好地理解这种表面形成过程。这种制作表面的新方法开辟了许多有趣的应用程序。例如，表面模拟了在病毒表面上存在的蛋白质尖峰，这些蛋白质尖峰被大自然用来鉴定靶细胞，参与进入细胞的进入，并防止抗体鉴定。这些材料可用于研究细胞对从工作方式到免疫系统行为的主题的行为。由于尖峰是垂直对齐的，因此它们也可以充当纳米线，因此它们可以用于太阳能电池和电池等能源生产和存储系统。最后，这些尖峰可能是压电，即它们可以将电能转换为运动（或声音）和运动转换为电能。该研究计划还将成为一种机制，可以向学生传授聚合物和材料科学，创建全球意识的研究生，并使学生接触到协作环境。研究生将能够与我们的合作者的研究小组一起作为团队的一部分，并参加交流访问。从这些研究计划中汲取的教训将用于教授K-12学生，并在高中教师的讲习班中应用。第2部分：技术摘要：使用生命自由基聚合方法合成的线圈聚合物刷将与杆刷结合使用，其持久长度是由使用各种生活和伪生活化学的表面生长的高持久性长度。相位通过溶剂加工和受纳米光刻指导的相分离将用于控制面内结构。各种化学和过程方法将用于限制宏观相分离，从而直接组装地形和化学结构。刷子生长将采用新的，化学定制的刷子启动器来用于单链和二元链生长，以形成杆圈混合刷配对。为了直接刷子结构和杆线相分离，使用最先进的光刻方法来控制刷子尖峰的间距，将以10s纳米的长度尺度上图案。将将刷子组织与计算预测进行比较，该预测将用于指导刷子设计和选择，并预测所得的物理结构和辅助表征研究。刷子的表征将使用多种分析方法进行，包括放牧发生率（GI）SAX和蜡，中子反射率和谐振软X射线散射（RSOXS）测量。对杆圈刷膜的电导率和压电特征的研究将有助于我们理解混合刷结构。通过合作，将这些材料作为细胞膜底物进行研究，用于针对性的生物分子结合，作为压电和具有异常运输途径的材料，还将提供有关关键长度尺度和底刷组织的信息。该奖项反映了NSF的法定任务，并通过使用基金会的智力优点和更广泛的影响审查标准来评估值得支持。

项目成果

Using Liquid Crystals to Probe the Organization of Helical Polypeptide Brushes Induced by Solvent Pretreatment

利用液晶探测溶剂预处理诱导的螺旋多肽刷的组织

• DOI: 10.1021/acs.macromol.1c01125
• 发表时间: 2021
• 期刊: Macromolecules
• 影响因子: 5.5
• 作者: Tsuei, Michael;Tran, Hai;Roh, Sangchul;Ober, Christopher K.;Abbott, Nicholas L.
• 通讯作者: Abbott, Nicholas L.