以阿拉伯树胶为分散剂,采用液相还原法制备超细银粉.探讨分散剂种类、pH 值和温度对银粉形貌和粒径的影响.研究表明,阿拉伯树胶通过化学吸附作用可以更好地吸附在银粒子表面,且比其他分散剂具有更好的分散作用.通过调节pH值,银粉的粒径可在0.34~4.09 μm的范围内调节;通过改变反应温度可以控制银粉的表面形貌.在21.8~70 ℃的温度范围内,可成功制备振实密度大于4.0 g/cm3的银粉.在50℃的最优温度下,银粉的振实密度大于5.0 g/cm3.该合成方法具有条件温和、银浓度高的优点,是一种合成用于电子浆料的高品质银粉的有前景的方法.%The ultrafine silver powders were prepared by liquid reduction method using Arabic gum as dispersant. The effects of different dispersants, pH values, and temperature on the morphology and particle size of silver powders were investigated. It is found that Arabic gum can better adsorb on silver particles via chemical adsorption, and it shows the best dispersive effect among all the selected dispersants. The particle size of silver powders can be finely tuned from 0.34 to 4.09 μm by adjusting pH values, while the morphology of silver powders can be tuned by changing the temperature. The silver powders with high tap density higher than 4.0 g/cm3were successfully prepared in a wide temperature range of 21.8-70 ℃. Especially, the tap density is higher than 5.0 g/cm3 when the temperature is optimized to be 50 ℃. The facile process and high silver concentration of this method make it a promising way to prepare high quality silver powders for electronic paste.
展开▼
