【摘要】 为了提高纳米铜粉的抗氧化能力及其在聚合物基体中的分散性,在钠米铜粉表面包覆一层导电性和抗氧化性均佳的银.以水合肼为还原剂、PVP(聚乙稀吡咯烷酮)和硅烷偶联剂(KH-550)为分散剂,采用二月桂酸二丁基锡对纳米铜颗粒表面进行活化处理,然后采用置换反应法制备得到了与原纳米铜粉粒径和形貌大致相同的核壳型铜-银双金属粉末.采用X射线衍射(XRD)、XRF、TGA等手段分析了核壳铜-银双金属粉的抗氧化性能,并用透射电子显微镜(TEM)对粉末形貌进行表征.结果表明,经表面活化处理后得到的核壳铜-银双金属粉,在镀银质量分数较低(37.68%)时也能形成完全包覆型结构.包覆后的铜纳米颗粒在700℃以下没有任何氧化现象.更多还原

【Abstract】 Cu nanoparticles were encapsulated in Ag shell for a better conductivity,antioxidation and improved particle dispersion.The surface of Cu nanoparticles was activated by C32H64O4Sn,and then reacted in a solution of AgNO3 to fabricate Cu-Ag bimetallic nanoparticles through the chemical dispalcement reaction method.Hydrazine hydrate was served as the reducer,PVP and KH-550 as the dispersants.The mean particle size and characteristics of Cu-Ag bimetallic nanoparticles were similar to the original Cu nanoparticles.The antioxidation behavior of nanoparticles was investigated by means of XRD,XRF and TGA.The nanoparticle morphologies were observed by TEM.It is indicated that the core/shell type microstructure can be formed as the content of Ag reaches about 37.68wt% in Cu-Ag bimetallic nanoparticles which can not be oxidized till to 700 ℃ in air.更多还原