The Preparation Of Metallic Fabrics With PD-Free Activation And Research Of Its Properties

Application of Metallic Fabrics was not only in electromagnetic interference (EMI) shielding, antistatic, ultraviolet resistance, antiseptic industries,but also in heat storage materials, blackout and energy-saving curtain, infrared reflecting materials, radar reflecting materials. There were lots of problems in the fields of textiles'surface metallization:(1):Activating agent PdC12 was more expensive. (2) Pre-treatment process of electroless plating was complex and hard to control. (3)The adhesive strength between the coating and the fabric was low. In this paper, pre-treatment process was studied, The adhesive strength between the coating and the fabric substrate can be improved significantly. The technology of electroless plating was discussed, a dense,uniform silver coating layer was successfully deposited on the nylon substrate by activation-reduction one-step electroless deposition. Study on optimum conditions of preparation of Ag-Ni duplex plating fabrics.Firstly, this papar make a systemic research on the influence of nylon fabric surface in pre-plating conditions on the square resistance, the rate of metal deposition and the adhesive strength, the reaction parameters including the preparation conditon of the polyaniline films,sensitizer concentration,the temperature and time of sensitization. The optimum conditions were as follows:aniline hydrochlorides 0.5mol/L, immersing time of aniline hydrochlorides 60min, ammonium persulfate 0.2mol/L, treating time of oxidation liquid 5s; SnCl2 10g/L, sensitization temperature 35℃, sensitization time 10min. The surface of polyaniline coated fabrics was investigated by SEM and AFM in detail, the laundry resistance, friction resistance performance was also investigated.Secondly, using activation-reduction one-step electroless deposition, silver was deposited homogeneously on the surface of polyaniline coated nylon fabric by electroless plating without using conventional palladium chloride solution activator. Effect of electroless plating conditions such as dosage of silver nitrate, reducing agent glucose, complexing agent ammonium hydroxide. sodium hydroxide, time, temperature and ultrasonic power on the square resistance, the rate of metal deposition and the adhesive strength were studied. Using the perpendicularity experiment, Optmium electroless plating conditions were 30℃,50min,100W with silver nitrate 14g/L, ammonium hydroxide 100mL/L, glucose 2.8g/L, sodium hydroxide 9g/L. Meanwhile, effect of the intermediate polyaniline layer on apparent performance, corrosion-resistant, laundry resistance, friction resistance and EMI properties of electroless plating silver fabrics was discussed. The results showed that the conductive propertie and N coordinated with the metal of intermediate polyaniline layer could improve compactness of silver, the adhesive strength,conductive, the corrosion-resistant, laundry resistance, friction resistance and EMI properties of electroless Plating silver fabrics.Finally, preparation of Ag-Ni duplex plating fabrics by step on the basis of surface activation without using palladium salt was studied. Effect of electroless plating nickel conditions such as dosage of nickel sulfate, reducing agent sodium hypophosphite, complexing agent sodium citrate, buffer boric acid, time and temperature on weight gain, square resistance of the Ag-Ni duplex plating fabrics and binding properties were discussed. Optmium electroless plating conditions were 65℃,40 min, pH 10, nickel sulfate 24g/L, sodium hypophosphite 26g/L, sodium citrate 20g/L, boric acid 26g/L. The properties and the structure of Ag-Ni duplex plating fabrics were investigated by SEM,AFM,XPS,VSM,TG and the performance analysis of corrosion-resistant, laundry resistance, friction resistance. The results showed that the Ag-Ni duplex plating fabrics with good corrosion-resistant, laundry resistance, friction resistance can be prepared.The results indicated that the different electrical and ferromagnetic property of Ag-Ni duplex plating fabrics could be obtained by adjusting the concentration of silver nitrate and nickel sulfate.