Preliminary study on the use of chitosan in nickel coated polyester paper

The preparation of nickel coated PET paper has been carried out by chemical or electroless plating using a hypophosphite-based bath. Chitosans of vari ous types and viscosity were used to surface treat chemicals. Their perform ances as surface treatment chemicals in electroless plating compared to 3-a minopropyltriethoxysilane (APS) were studied. The results showed that when PET paper pretreated by chitosans were plated at 65 degrees C, pH 6.5 and 7.5, the reactions were rather sluggish compare d to those by APS. Whereas at 75 degrees C, pH 7.5, the reaction rate and t he amount of nickel deposition of PET paper treated by APS, chitosan A and chitosan B were comparable, which were 52.6, 53.2 and 54.7 g/m(2), respecti vely. Their electromagnetic interference (EMI) shielding effectiveness showed a l inear relationship with the amount of nickel deposition and were closely re lated to their surface resistivity of nickel coated PET paper. In addition, EMI shielding effectiveness of nickel coated PET paper pretreated by APS, chitosan A and chitosan B were over 40 dB and their surface resistivity wer e less than 5 x 10(-2) Omega/square.