Responsive Films Derived from Weak Polyelectrolyte Multilayers

由弱聚电解质多层衍生的响应薄膜

• 批准号: 0513197
• 负责人: Svetlana Sukhishvili
• 金额: $ 30万
• 依托单位: Stevens Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0513197&HistoricalAwards=false
• 关键词: Responsive; Films; Derived; Weak; Polyelectrolyte

TECHNICAL EXPLANATION The objective of the project is to explore principles and develop strategiesfor transforming polyelectrolyte multilayers (PEMs) into highly functional pH-, ionicstrength- and/or temperature-responsive coatings which reversibly trap or releasesynthetic macromolecules and proteins. New knowledge generated in this project aboutphysical and chemical ways to stabilize polymer films at surfaces will be a significantcontribution to materials and polymer science. Specifically, the project will provide a wealth ofinformation on issues pertaining to molecular design of building block for responsive polymerself-assembly, derivatization of PEMs into active surface coatings and potential capabilitiesin PEM-based regulation of surface adhesion and absorption properties.Our approach will be based on a combination of molecular engineering and synthesis ofpolymeric 'building blocks' of PEMs with the chemical composition necessary for furthertransformation of PEMs into an absorbing film. We will explore several routes of producingsurface-attached active absorbing films using electrostatic or hydrogen-bonded polymermultilayers as a starting material. The first route will be based on the dissociation of componentsof electrostatically assembled multilayers at high concentrations of small ions combined withselective 'salting-out' of one of the film components. In another scenario, we will explorechemical crosslinking of hydrogen-bonding multilayers as a means to produce surface-attachedhydrogels. One-component hydrogels of polycarboxylic acids will be produced by selectivecrosslinking of self-assembled polycarboxylic acids and further release of hydrogen-bondedpolymers from the crosslinked polyacid matrix. Two-component hydrogels will be obtained byreacting end-functionalized hydrogen-bonding polymers with carboxylic groups of selfassembledpolyacid. In the latter type of absorbing films, response and absorbing properties willbe modulated through intermolecular adhesion between hydrogen-bonded polymer chains.Selective monitoring of film composition, ionization of functional groups and quantification ofcharge balance will be done using in situ ATR-FTIR. The data will be correlated with the resultsof film swelling as measured with in situ ellipsometry and in situ AFM. The question of howinterpolymer interactions respond to environmental stimuli, and how they are translated intochanges in film density and absorption properties will be addressed.NON-TECHNICAL EXPLANATION The use of produced films as re-loadable matrices that could reversibly andcontrollably absorb and desorb macromolecules and proteins from response to environmentalstimuli, specifically valuable for separation, concentration, and controlled release of chemicalsand proteins in environments with dominating effects of surfaces such as in a microfluidicchannel. Results of proposed research will be made available to a broad scientific audiencethrough conference presentations, invited talks given by the PI of this project, poster and oralpresentations of graduate students, and archival literature.The educational impact includes building a stronger interdisciplinary polymer program atStevens that will provide better training for students. The results of the proposed research will beincluded into recently developed advanced polymer courses, such as Polymers at Solid-LiquidInterfaces, and other core laboratory courses at both graduate and undergraduate levels.Participation of women in advanced research will be enhanced also through support of twofemale graduate students. Finally, economically disadvantaged high school students will begiven an opportunity to be exposed to this research due to activities our group sustains in theACS SEED program.

技术解释 该项目的目标是探索原理和开发策略，将纳米多层膜（PEM）转化为高功能的pH，离子强度和/或温度响应涂层，可逆地捕获或释放合成的大分子和蛋白质。该项目中产生的关于稳定表面聚合物膜的物理和化学方法的新知识将对材料和聚合物科学做出重大贡献。具体而言，该项目将提供丰富的信息有关的问题，分子设计的积木响应聚合物自组装，将PEM衍生为活性表面涂层和PEM的潜在能力-我们的方法将基于分子工程和合成聚合物“积木”的PEM与化学成分的必要的组合，进一步将PEM转化为吸收膜。我们将探索以静电或氢键聚合物多层膜为起始材料制备表面附着活性吸收膜的几种途径。第一条路线将基于在高浓度的小离子结合选择性的“盐析”的膜组件之一的静电组装的多层膜的组件的解离。在另一种情况下，我们将探索化学交联的氢键多层膜作为一种手段，以产生表面附着的水凝胶。单组分聚羧酸水凝胶的制备是通过自组装聚羧酸的选择性交联和进一步从交联的聚羧酸基质中释放氢键聚合物来实现的。通过末端功能化的氢键聚合物与自组装多酸的羧基反应，可得到双组分水凝胶。在后一种类型的吸收膜中，响应和吸收性能将通过氢键聚合物链之间的分子间粘附来调节，膜组成的选择性监测，官能团的电离和电荷平衡的定量将使用原位ATR-FTIR。这些数据将与用原位椭圆偏振法和原位原子力显微镜测量的膜溶胀的结果相关联。将讨论聚合物间的相互作用如何响应环境刺激，以及它们如何转化为薄膜密度和吸收性能的变化。非技术性解释 所制备的膜作为可可逆地和可控地从对环境刺激的响应中吸收和解吸大分子和蛋白质的吸收基质的用途，特别是对于在具有表面的主导作用的环境中例如在微流体通道中分离、浓缩和控制释放化学物质和蛋白质有价值。建议的研究结果将通过会议报告，该项目的PI邀请的演讲，研究生的海报和口头报告以及档案文献提供给广泛的科学观众。教育影响包括在史蒂文斯建立一个更强大的跨学科聚合物项目，为学生提供更好的培训。拟议研究的结果将纳入最近开发的高级聚合物课程，如固液界面聚合物，以及研究生和本科生的其他核心实验室课程，还将通过支持两名女研究生来加强妇女对高级研究的参与。最后，经济困难的高中学生将有机会接触到这项研究，由于活动，我们的小组在ACS种子计划维持。