纳米银粉表面包覆硅烷偶联剂改性研究

Surface Modification of Silver Nano-Powders with Silane Coupling Agent

为了减少纳米银粉的团聚,增强纳米银粉在空气中的稳定性,提高其与有机材料的亲合性,改善纳米银粉在有机基体中的均匀分散,需预先对纳米银粉进行表面改性。采用硅烷偶联剂KH-560对纳米银粉进行表面改性,通过测定活化指数,研究了KH-560用量与纳米银粉改性效果之间关系,并借助X射线衍射仪(XRD)、红外光谱(FTIR)、紫外可见分光光度计(UV-vis)等测试手段,对改性后纳米银粉的结构和性能进行了表征。XRD结果表明,纳米银粉为面心立方晶系,晶粒尺寸约为20 nm;通过活化指数的测量,KH-560最佳用量为5%,改性后纳米银粉疏水性增强,活化指数达0.8;红外光谱表明,KH-560以化学键合的方式结合在纳米银粉的表面,并形成了有机包覆层;UV-vis结果表明,改性后的纳米银粉在氯仿中具有较好的分散稳定性。

In order to reduce agglomeration of the silver nano-powders,increase their dispersing stability in air and improve their compatibility with other organic materials,its surface modification should be pretreated.The surface of silver nano-powders was modified with silane coupling agent KH-560.The relationships between the usage of KH-560 and silver nano-powders were also studied by measuring active index.The modified silver powders were characterized by X-ray diffraction（XRD）,Fourier transform infrared spectra（FTIR） and UV-visible spectrophotometer（UV-vis）.XRD curve showed that the silver nano-powders belonged to face-centered cubic crystal system and the crystalline grain size was about 20 nm.The active index experiments indicated that the optimal usage of KH-560 was 5%.The hydrophobicity of modified silver powders was improved obviously and the active index reached 0.8.The FTIR indicated that chemical bond existed between silver nano-powders and KH-560.UV-vis curves showed that the modified silver nano-powders had good dispersity and stability in chloroform.