Formation of Nanostructures in Hydrogels

9612386 Chu本研究旨在利用水凝胶中组织良好的微非均质性来开发和研究金属纳米颗粒。本文提出了两种类型的微非均质性：由于聚电解质/疏水相互作用的竞争而导致微相分离的弱电荷聚电解质水凝胶的研究，以及可以形成高度有序的超分子纳米/微观结构的水凝胶/表面活性剂体系的研究。金属离子可以被贵金属或稀土离子取代，其随后的还原将在凝胶或微凝胶颗粒内形成金属纳米颗粒。水显然是溶剂的最佳选择，原因有很多，包括环境因素，在水介质中发生的广泛催化反应的潜在用途，以及生物应用的可能性。在凝胶中合成金属纳米粒子是非常有用的，因为这种高响应介质对外部水溶液的任何变化都有很高的敏感性。我们的目标是控制金属非颗粒的大小和形状，以及聚合物的性质，如网状尺寸，以调节金属纳米颗粒和表面的催化活性。这项研究是在纳米技术领域，应该有助于为设计和环保处理聚电解质、凝胶和纳米颗粒奠定基础。＊＊＊

9612386 Chu This research aims to develop and study metal nanoparticles by taking advantage of the well-organized microheterogeneities in hydrogels. Two types of such microheterogeneities are proposed: the study of weakly charged polyelectrolyte hydrogels with microphase separation due to the competition of polyelectrolyte/hydrophobic interactions, and hydrogel/surfactant systems which can form highly ordered supramolecular nano/microstructures. The metal ions can be replaced by noble or rare earth ions whose subsequent reduction will then bring to the formation of metallic nanoparticles inside the gels or microgel particles. Water is obviously the best choice as a solvent for a number of reasions, including environmental considerations, potential use for widespread catalytic reactions which take place in aqueous media, and the possibility for biological applications. The synthesis of metal nanoparticles within the gels which can swell intensively in water should be very useful, because the highly responsive medium has a high susceptibility to any changes of the external aqueous solution. We aim to control the size and the shape of metal nonoparticles, as well as the polymer properties, such as mesh size, in order to regulate the catalytic activity of metal nanoparticles and surfaces. %%% This research is in the area of nanotechnology and should help to lay the foundation for design and environmentally conscious processing of polyelectrolytes, gels, and nanoparticles. ***