| As a new material, conductive fabric has some important applications in many fields. This paper put forward to a kind of pretreatment method for chemical plating which is based on mercapto modification of fiber surface, forming a silver active layer on the surface of fiber to initiate electroless silver plating. The traditional method of sensitization and activation has been improved by this method which also has overcame complex process in the original method,the weak binding between precious metals and the substrate,the high consumption of precious metals and poor environmental drawbacks. The excellent results of silver conductive fabric containing good conductive,electromagnetic shielding performance and good adhesion of the metal plated layer and the fabrics can be achieved by electroless silver plating after the polyester and cotton modified with mercapto. The process has good application prospects.The topic of electroless silver plating on the fiber modified with 3-mercaptopropyltriethoxysilane were brought forward and the processes of making silver plating conductive fabric modified by mercapto are as following. Removing oil, coarsening and mercapto modifying constitute of the surface treatment of polyester fiber while the cotton fiber need the treatment of scouring and mercapto modifying. Then the implementation of the plating can start with the fabrics immerging into oxide- reduction system of silver plating solution. The conductive of fabrics coated with silver can be obtained. The research paper uses the polyester fiber as a substrate, and polyester fiber has experienced coarsening after the oil removing. The purposes of coarsening are as follows. First of all, rough surface of polyester fiber can be formed by this to improve physical adsorption. Second, It makes the polyester fiber surface rich in hydroxyl groups, which is prerequisite for chemical coupling of silane with mercapto group. There are several factors affecting the result of conductive fabrics when studying on the optimum technics of modification under the mature condition of chemical silver plating. By using resistance of silver plating fabrics and its dispersion as a criteria, the optimal process of modification are:the mass fraction of 3-mercaptopropyltriethoxysilane 1%,the modification time 120 min,the bath ratio of modification liquid 1:60. On this basis, the optimal process of silver plating can be obtained by improving the original process:concentration of silver nitrate 20.8g/L, concentration of glucose 24.8g/L, plating time 70min, plating temperature 50℃. The SEM and XPS results showed that a uniform and dense silver coating was formed on the surface of polyester fiber after chemical plating. And there exist a high fastness adhesion between the silver coating and polyester fiber. The stability of fabrics conductivity is good. But the mechanical properties of silver plating PET are decreased due to the coarsening of polyester fiber.As a substrate, cotton fiber was modified with mercapto after scouring. Then the implementation of the plating can start. Combining the orthogonal test and single factor analysis, the optimal process of electroless silver plating cotton with mercapto modifying is:the mass fraction of 3-mercaptopropyltriethoxysilane 1%,the modification time 120 min, the bath ratio of modification liquid 1:60, concentration of silver nitrate 20.8g/L, concentration of glucose 22.5g/L, plating time 50min, plating temperature 40℃. The scanning electron microscopy results showed that there exist nanoscale silver presentation in the starting silver catalyst layer, and the size of silver become larger on the follow-up silver coating. The SEM and XPS results showed that a uniform and dense silver coating was formed on the surface of cotton fiber after chemical plating. Silver plating cotton fabric, with excellent electromagnetic shielding, as well as good combination of silver plating and good stability of the silver-plated cotton fabric conductivity, has little change of mechanical properties.
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