摘要：以抗坏血酸为还原剂, 明胶为分散剂, 硝酸银为反应前驱体, 采用液相还原法制备超细银粉, 研究明胶用量及加入方式对银粉形貌、粒径及分散性的影响, 探讨明胶的分散机制, 利用X射线衍射分析、能谱分析、扫描电镜和透射电镜对银粉进行表征。结果表明, 超细银粉为近球形, 粉体颗粒粒径为0.11.2μm;明胶对银粉的形状无明显影响, 但是可以改变银粉的粒径和分散性;随着明胶用量的增大, 粉体的粒径增大, 分散性能变好;明胶的分散机理主要表现为空间位阻机制。

关键词：超细银粉；明胶；分散机理

Abstract：With ascorbic acid as reductant, gelatin as dispersant, AgNO3 as reaction precursor, ultra-fine sliver powders were prepared by liquid phase reduction method. The effects of dosage and adding ways of gelatin on particle size, morphology and dispersion were investigated, and the dispersion mechanism of gelatin was explored. The silver powders were characterized by means of XRD, EDS, SEM and TEM. The results show that the ultra-fine silver particles are nearly spherical, and 0.1 to 1.2 μm in size. There is no significant effect of gelatin on the morphology of silver particles, but some effects on the particle size and the dispersion. As the dosage of gelatin increase the size of silver particles is larger, the dispersion is better. The dispersion mechanism of gelatin is mainly stereohindrance effect.

Keywords：ultra-fine silver powder; gelatin; dispersion mechanism