滑石粉化学镀银条件的探讨

Study on the Electroless Silver Plating of Talcum Powder

摘要:

以甲醛为还原剂，采用银氨液滴入还原液的镀液加入方式进行化学镀银法制备导电滑石粉，对滑石粉化学镀银条件进行了研究。探讨了银氨液pH值、硝酸银浓度、甲醛浓度、粉体装载量以及反应时间等因素对滑石粉化学镀银的影响规律。借助FESEM对镀银后滑石粉的表面形貌进行了表征，测试了化学镀银后滑石粉的增重率、压实厘米电阻。在以上分析基础上，得出滑石粉化学镀银的最佳工艺条件为：银氨液pH值11.7，硝酸银10 g/L，甲醛13 mL/L，装载量25 g/L，反应时间60 min，得到的镀银滑石粉的厘米电阻为23.6 Ω×cm

Abstract:

Talcum powder has potential application in the field of conductive fillers preparation because of its particular structure. The conductive talcum powder was prepared by electroless silver plating with the way of silver ammonic solution dipping into the reduction solution with formaldehyde as reductant. The conditions of electroless silver plating for talcum powder were studied. Effects of pH value of the silver ammonic solution, concentration of the silver nitrate and formaldehyde, loadage of the powder and plating reaction time on the powder mass gain of coated silver were discussed. With the aid of FESEM, the morphology of talcum powder after silver plating was characterized; the rate of mass gain and the resistivity of the compacted talcum after silver-plating were tested. On the basis of the above analysis, the best conditions of electroless silver plating on talcum powder are drawn: pH value of silver ammonic solution 11.7, concentration of silver nitrate 10 g/L and that of formaldehyde 13 mL/L, loadage 25 g/L, and reaction time 60 min. Under these conditions, the resistivity of the compacted talcum powder after silver plating was 23.6 Ω×cm.