Study Of Electroless Nickel Plating And Electroplating On Polypropylene Modified By Organosilane Self-assembled Nanofilm

Polypropylene(PP)is a kind of important thermoplastic plastics,metalized PP with the advantages of plastic and metal can further expand its application areas,such as electron,precision instruments,electrical appliances,chemical industry and so on.In this paper,corona was used in the electroless nickle plating before self-assembly.APTES was used to prepare self-assembled film on corona PP surface.Then APTES film modified PP was treated b y electroless nickel plating and electrical nickel plating.Nickel coating was covered on the surface of PP by electroless plating process and electrical plating.Contact angle,coating apparent analysis,bond test,coating thickness and the plating speed,SEM,EDX and C V were carried out to study the results of the preparation of APTES film and nickel coating.The experimental results are as follows:(1)The APTES pretreatment process of the preparation of self-assembled film was studied,which was under the optimal corona time of 60 s,Results showed that the strong chemical bonds formed on the PP surface,which increased the surface roughness and laid a foundation for electroless nickle plating.(2)By orthogonal test,the best process conditions for electroless nickel platinger were as follows: nickel plating liquid concentration of 9 g/L under p H of 5.5 and time of 30 min,nickel sulfate of reduction of nickel of 4 g/L under 40?,potassium borohydride of reduction of nickel of 5 g/L under 40?.The bond test and SEM showed nickel coating on the surface of the PP reflected strong adhesive power,which was closely packed and orderly distribution,but there existed a certain degree of particle aggregation.EDX showed that the nickel content was high,but there existed a small amount of impurities.(3)The current density of electroplating nickel layer thickness and the plating rate wer e studied,The highest current density and the longest electroplating time were 9 m A/cm~2 and 10 min,respectively.At the same time,under this condition the nickel plating layer thickness(1.412 ?m),plating speed(0.141 ?m /min)would reach the maximum value.(4)The best conditions in electroplating nickel were explored under different cur rent density and time.Through the cyclic voltammetric curves,the magnitude of the compactness were listed in the order:(5 m A/cm~2;7 min)>(3 m A/cm~2;7 min)> electroless plating >(7 m A/cm~2;7 min)>(9 mA/cm~2;7 min).So the current density of 5 mA/cm~2 and electroplating time of 7 min were the best conditions,the thicknesses of the coating was about 1.084 ?m.SEM and EDX showed that compared with the electroless plating nickel layer,electroplating nickel layer revealed more closely packed and equally grained.In the meantime,the content of nickel element was improved greatly.