Studies On Preparation Of Copper-Silver Composition Plating Film And Applied On Polyester Fabric

Carboxylic styrene butadiene latex has wide range of applications because of its excellent film-forming and adhesive properties. The products have many excellent properties, such as anti-aging, solvent resistance, heat resistance. That leads to a new direction for development and preparation of functional materials.Using the excellent film-forming of carboxylic styrene butadiene latex, the autocatalytic activity film was prepared with added palladium chloride in the emulsion. As a kind of flexible non-metallic material, the film has potential applications. Copper-silver metal layer coated on the film using electroplating and electroless plating methods in this experiment has good conductivity and corrosion resistance. Through this method, it can be directly used to electroless copper on the film without roughening, sensitization and activation. Compared with other method, it not only simplified the process of electroless copper, but also shortened the time and improved the efficiency. The optimum preparation of film was drawn through orthogonal experiment and single-factor experiments, the results were as follows:concentration of carboxylic styrene butadiene latex30%, concentration of palladium chloride0.01%, treatment temperature80℃, treatment time1h, then baking5min at temperature100℃. The optimum conditions of electroless copper were as follows:concentration of CuSO48g/L, concentration of NiSO40.6g/L, concentration of NaH2PO235g/L, concentration of Citric acid25g/L, treatment temperature50℃, treatment time0.5h. The optimum conditions of electroplating silver were as follows: concentration of silver nitrate20-25g/L, concentration of Na2S2O3200g/L, concentration of K2S2O540～50g/L, current density0.5～0.6A/dm2.The metal coating was characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), and energy-disperse spectroscopy(EDS). Rate of weight gain and deposition rate were also measured. The results indicated that the metal layer was uniform and compact on the film. The resistance reaches200～300mΩ, the test showed that film had excellent conductivity and corrosion resistance.On the basis of chapter two, the method was applied to polyester fabric without roughening and sensitization. The optimum conditions of pretreatment were as follows:concentration of carboxylic styrene butadiene latex3%-4%, concentration of palladium chloride0.02%-0.03%, baking5min at temperature120℃. Electroless copper and electroplating silver were carried out after pretreatment. The results showed that the electromagnetic shielding effectiveness of polyester fabric reached70dB.The substrate was treated using DX-955protective agent which could protect silver layer in case of discoloration and oxidation. At the same time, the substrate can keep smooth and bright.