Reactions of Functional Polymers at Organic Interfaces

功能聚合物在有机界面的反应

• 批准号: 0704054
• 负责人: Jeffrey Koberstein
• 金额: $ 49.2万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0704054&HistoricalAwards=false
• 关键词: Reactions; Functional; Polymers; Organic; Interfaces

TECHNICAL SUMMARY:Interfacial reactions involving polymers are far more complex than reactions involving small molecule reactants because of the broad range of variables that can affect their molecular structure and behavior at interfaces. While interfacial reactions are a part of many polymer applications, a fundamental understanding of the parameters affecting them is generally lacking. The scientific goal of the proposed research plan is therefore to provide a fundamental and quantitative understanding of the factors that influence the reactions of polymers at organic interfaces. The achievement of this goal is the deliverable of this project: a fundamental basis for both the molecular design of polymer interfacial reactions and for the subsequent control of the interfacial properties they bring about. Two model reaction systems have been selected for study to represent the wide variety of reactions that may be encountered in practice: . a "standard" reaction between a functional polymer and an organic surface containing a complementary functional group . a photografting reaction between a polymer in contact with an organic surface, one of which contains a photoactive group capable of grafting the polymer to the surface.The functional polymers required for the research will be prepared by atom transfer radical polymerization. The proposed research investigates how interfacial reactions are influenced by factors such as: solvent quality and concentration, including neat polymers; molecular weight; areal density of functional groups; location of functional groups along the polymer backbone; the nature of the surface interaction parameter, state of the polymer (i.e., glassy or rubbery), conditions of the photochemical reaction and reaction time. The organic interfaces employed will be prepared on either silicon wafers or gold-coated wafers in order to enable characterization of the reactions by a barrage of techniques including: x-ray photoelectron spectroscopy, grazing incidence reflection infrared, ellipsometry, contact angle, MALDI-TOF mass spectrometry, fluorescence spectroscopy and gel permeation chromatography. The research program also includes validation of a new concept, covalent layer-by-layer assembly, in which multiple polymer layers are successively built up on an organic substrate wherein each layer is covalently bound to the previous layer.NON-TECHNICAL SUMMARY:The nature of how long chain molecules react at interphases is an important underlying aspect of many applications involving polymers and biomacromolecules. Such reactions are used to control surface properties of materials and coatings such as adhesion and wettability, are employed to make magnetic nanoparticles soluble in water for potential use as magnetic resonance imaging contrast enhancement agents, and are used in the fabrication of biosensors wherein DNA, proteins, antibodies and antigens are chemically bound to substrates to form diagnostic microarrays. The proposed research program will provide a scientific basis for the design of such reactions and their optimization for use in these applications. This enabling technology will play an important role in the manufacturing of inexpensive DNA sequencing chips, clothing that can filter out harmful pathogens and rapid diagnostics that can identify dangerous pathogens and antigens.The proposed research will also have a broad impact on research and education through a number of programs: the training of undergraduate and graduate researchers, hosting of a summer high school chemistry teacher researching interfacial reactions and with that teacher, the development of modules on polymer chemistry suitable for use in his classes. The P.I. will also continue his outreach efforts to Columbia University undergraduate students at large through his activities as a Professor in Residence, living amongst the students in a dormitory and hosting informal dinners with undergraduates and a special guest talking on a topic related to the series theme "Society and Technology".

涉及聚合物的界面反应比涉及小分子反应物的反应复杂得多，因为可以影响其分子结构和界面行为的变量范围很广。虽然界面反应是许多聚合物应用的一部分，但通常缺乏对影响它们的参数的基本理解。 因此，拟议的研究计划的科学目标是提供一个基本的和定量的了解的因素，影响聚合物在有机界面的反应。这一目标的实现是该项目的可交付成果：为聚合物界面反应的分子设计和随后对它们所带来的界面性质的控制奠定了基础。已经选择了两个模型反应系统进行研究，以代表实践中可能遇到的各种反应：功能聚合物和含有互补官能团的有机表面之间的“标准”反应。一种聚合物与有机表面接触的光接枝反应，其中一个有机表面含有能够将聚合物接枝到表面的光活性基团。研究所需的功能聚合物将通过原子转移自由基聚合制备。拟议的研究调查了界面反应如何受到以下因素的影响：溶剂质量和浓度，包括纯聚合物;分子量;官能团的面密度;官能团沿着聚合物主链的位置;表面相互作用参数的性质，聚合物的状态（即，玻璃状或橡胶状）、光化学反应条件和反应时间。所采用的有机界面将在硅晶片或镀金晶片上制备，以便能够通过一系列技术表征反应，包括：X射线光电子能谱、掠入射反射红外、椭圆偏振、接触角、MALDI-TOF质谱、荧光光谱和凝胶渗透色谱。该研究计划还包括一个新的概念，共价层层组装，其中多个聚合物层依次建立在有机基板上，其中每一层是共价键连接到前一层的验证。非技术摘要：长链分子在界面反应的性质是许多应用涉及聚合物和生物大分子的一个重要的基本方面。 这种反应用于控制材料和涂层的表面性质，例如粘附性和润湿性，用于制备可溶于水的磁性纳米颗粒以潜在地用作磁共振成像对比度增强剂，并且用于制造生物传感器，其中DNA、蛋白质、抗体和抗原化学结合到基底以形成诊断微阵列。拟议的研究计划将为此类反应的设计及其在这些应用中的优化提供科学依据。这项技术将在制造廉价的DNA测序芯片、过滤有害病原体的衣服以及识别危险病原体和抗原的快速诊断方面发挥重要作用。拟议的研究还将通过一些项目对研究和教育产生广泛影响：本科生和研究生研究人员的培训，接待一名研究界面反应的暑期高中化学老师并与该老师一起，开发适合他的课程使用的高分子化学模块。私家侦探 他还将继续他的推广工作，哥伦比亚大学本科生在广大通过他的活动作为一个教授在住宿，生活在学生宿舍和主办非正式晚宴与本科生和一个特殊的客人谈一个主题有关的系列主题“社会和技术”。