Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, V.le delle Scienze ed. 17, 90128 Palermo, Italy.
Department of Agricultural, Food and Forest Sciences (SAAF), University of Palermo, V.le delle Scienze ed. 4, 90128 Palermo, Italy.
J Phys Chem B. 2020 Mar 5;124(9):1847-1857. doi: 10.1021/acs.jpcb.9b11935. Epub 2020 Feb 26.
A fast-field-cycling NMR investigation was carried out on a set of polyurethane cyclodextrin nanosponges, in order to gain information on their textural properties, which have been proven to be quite difficult to assess by means of ordinary porosimetric techniques. Experiments were performed on both dry and wet samples, in order to evaluate the behavior of the "nonexchangeable" C-bound H nuclei, as well as the one of the mobile protons belonging to the skeletal hydroxyl groups and the water molecules. The results acquired for the wet samples accounted for the molecular mobility of water molecules within the channels of the nanosponge network, leading back to the possible pore size distribution. Owing to the intrinsic difficulties involved in a quantitative assessment of the textural properties, in the present study we alternatively propose an extension to nanosponges of the concept of "connectivity", which has been already employed to discuss the properties of soils.
我们对一组环糊精纳米海绵进行了快速场频循环 NMR 研究，以获取有关其结构特性的信息，这些特性通过普通的孔隙率技术很难评估。我们对干燥和湿润的样品进行了实验，以评估“不可交换”的 C 键合 H 核以及属于骨架羟基和水分子的可移动质子的行为。对湿样品获得的结果解释了水分子在纳米海绵网络通道内的分子迁移率，这可以进一步得到可能的孔径分布。由于对结构特性进行定量评估存在固有困难，在本研究中，我们提出了将“连通性”概念扩展到纳米海绵，该概念已被用于讨论土壤的性质。
