Mori Hideharu, Müller Axel H E, Klee Joachim E
Lehrstuhl für Makromolekulare Chemie II and Bayreuther Zentrum für Kolloide und Grenzflächen, Universität Bayreuth, Germany.
J Am Chem Soc. 2003 Apr 2;125(13):3712-3. doi: 10.1021/ja0297887.
We present novel intelligent colloidal polymer/silica nanocomposites, in which the complexation of cationic silica nanoparticles and a weak anionic polyelectrolyte can be manipulated simply by pH change through a hydrogen-bonding interaction and ionic complexation caused by hydrogen-transfer interactions between the constituents. Special silica particles which have nanometer size (diameter approximately 3.0 nm) and two independent proton-accepting sites were developed in this study. Both the silica and poly(acrylic acid) form transparent colloidal solutions in water, while a white turbid dispersion was obtained just after mixing the two solutions due to the complexation. The pH-induced association-dissociation behavior was confirmed by the turbidity and potentiometric titration measurements. The assembled structures of the hybrids were visualized by scanning force microscopy.
我们展示了新型智能胶体聚合物/二氧化硅纳米复合材料，其中阳离子二氧化硅纳米颗粒与弱阴离子聚电解质的络合可通过pH变化，经由氢键相互作用以及组分间氢转移相互作用引起的离子络合来简单操控。本研究制备了具有纳米尺寸（直径约3.0 nm）且有两个独立质子接受位点的特殊二氧化硅颗粒。二氧化硅和聚丙烯酸在水中均形成透明胶体溶液，但两种溶液混合后，由于络合作用会立即得到白色浑浊分散体。通过浊度和电位滴定测量证实了pH诱导的缔合-解离行为。通过扫描力显微镜观察了杂化物的组装结构。
