무전해 니켈 도금을 이용한 전도성 실리콘 고무 시트 제조

Abstract

This study prepared electromagnetic shield sheet by applying electroless nickel plating on flexible silicon rubber. Existing materials for electromagnetic shield preparation are mostly metals. However, metal has various demerits and development of new material became necessary. Some new electromagnetic shield materials are made by plating metals such as nickel, silver or copper on silicon rubber or other complex material. Among the various manufacturing methods, this study used electroless plating method. Various reaction conditions such as temperature and pH were controlled to make uniform quality electroless nickel plating film. 8cm x 8cm silicon rubber test pieces were used for this study. Since the specimen is nonconductor, it required pre-treatment. This study used mixed solution of sulfuric acid and nitric acid, mixed solution of tin(Ⅱ) chloride and hydrochloric acid and mixed solution of palladium(Ⅱ) chloride and hydrochloric acid in sequence. In each process, distilled water was used for washing. Regarding the plating solution, nickel chloride solution was used. For reducing agent, sodium phosphinate was used

while ammonium chloride was used as complexing agent. 0.5M potassium hydroxide solution was used for pH control. Then, temperature and pH were controlled to find optimum electroless plating conditions. First, test pieces were prepared while pH was increased from 5 to 8 with interval of 1. Second, test pieces were prepared while temperature was increased from 60℃ to 90℃ with interval of 10℃. The prepared test pieces were analyzed for their characteristics by XRD, SEM, adhesive power test and 4-point-probe sheet resistance test. It was possible to prepare uniform quality nickel plating film sheet at pH 7 and 70℃.