Structure, Dynamics and Transport in Self-Assembled Ionomeric Systems

9625451 Schlick本建议旨在研究全氟化和质子化离聚体在散装和溶液中的自组装，以及溶剂、离子含量和中和程度的函数。计划进行以下实验。(a)在乙醇、水、甲酰胺和n -甲基甲酰胺等介电常数范围为24至182的溶剂中，测量全氟化离聚体的F-NMR光谱与浓度的关系。将对这些线形进行分析，并与全氟聚合物和短链全氟表面活性剂的结果进行比较，以推断出低浓度下存在的最小单位和聚集程度。(b)中性、阳离子和阴离子示踪剂在全氟离子聚单体中的扩散系数将通过ESR成像测量，并与聚合物链的自组装程度和类型相关联。(c)为了了解主链对自组装的贡献，将通过自旋探针ESR方法和ESR成像研究溶液中、干燥状态和溶剂膨胀状态下的聚乙烯-共甲基丙烯酸（EMAA）离聚体，并将其作为离子单体（MAA）浓度的函数，以推断聚集体的动力学和聚合物-溶剂界面的曲率。(d)将在三个主要领域进一步发展电磁共振成像。采用傅里叶变换方法进行图像重建，减少了数据采集所需的时间，从而增加了可以推导出的扩散系数的范围；将装配二维空间成像所需的硬件和软件；为提高空间分辨率而设计的新型自旋探针将被制备出来。%%%提出的研究和收集自组装离聚体系统数据的方法被认为对研究药物输送系统中的运输过程很重要；人工晶状体和人工晶状体；制备新材料，包括催化剂；在生物系统中包括通过细胞膜的运输。＊＊＊

9625451 Schlick This proposal is directed to the study of self-assembling of perfluorinated and protiated ionomers in the bulk and in solution, as a function of the solvent, the ion content, and the degree of neutralization. The following experiments are planned. (a) F-NMR spectra of perfluorinated ionomers as a function of concentration will be measured in ethanol, water, formamide and N-methyl formamide, solvents that span a range of dielectric constants from 24 to 182. The lineshapes will be analyzed and compared with results for perfluorinated polymers and short-chain perfluorinated surfactants, to deduce the smallest unit that exists at low concentrations, and the degree of aggregation. (b) The diffusion coefficients of neutral, cationic and anionic tracers in perfluorinated ionomers will be measured by ESR imaging and correlated with the degree and type of self- assembling of the polymer chains. (c) In an attempt to understand the contribution of the backbone to self- assembling, poly(ethylene-co-methacrylic acid) (EMAA) ionomers in solution, and in the dry and solvent-swollen state, will be studied by the spin probe ESR method and ESR imaging as a function of the concentration of the ionic monomer (MAA), to deduce the dynamics of the aggregates and the curvature of the polymer-solvent interface. (d) ESR imaging will be further developed in three main areas. The time required for data acquisition will be reduced by a Fourier transform method for image reconstruction so as to increase the range of diffusion coefficients that can be deduced; the hardware and software necessary for 2D spatial- spatial imaging will be assembled; and novel spin probes designed to enhance the spatial resolution will be prepared. %%% The methods proposed for the study of, and collection of data on, self-assembled ionomer systems are considered important for the study of transport processes in drug delivery systems; in ocular and intraocular lenses; in preparation of new materials, including catalysts; and in biological systems that involve transport through cell membranes. ***