Study On Metallization Of Flexible Polymer Surface

The metallization of polymer surface has attracted more and more attention due to its potential applications in fields like surface protection,microelectronics industry,and surface decoration.Electroless plating is particularly attractive among these methods due to its low cost,limit effects on the surface of the matrix,and reliable capability for large area deposition.The pretreatment,activation and then plating are the most commonly process for the electroless plating.Pretreatment can improve the interfacial adhesion between metal catalysts and polymer surface.Several methods such as laser radiation and exposure to flames have been employed to modify the polymer surface.The expensive reagents were involved and the operation processes were tedious which raise the operation.The present work aims to develop a relatively simple,cost-and time-effective approach for electroless plating on the flexible polymer surface.The electroless plating on the polymer surface has been established basing on printing primer.The results and conclusions are summarized as follows:?1?Metallization of plant fiber non-woven sheet were prepared by electroless nickel plating.Results showed that the surface of plant fiber in the non-woven sheet contained amine groups,which were more prone to absorb palladium catalyst to form an active layer for electroless nickel plating.The weight change of non-woven sheet after electroless nickel plating was 33 %,and the average EMI-SE of nickel-plated sheets maintained a relatively stable value?30³5 d B?in a frequency range of 0.1¹.6 GHz.Pseudo-second-order and Freundlich model?multi-layer sorption?could describe the adsorption behavior of plant fiber non-woven sheet for Pd²⁺.The maximum adsorption capacity was 7.99×10-4 mg/g and second-order dynamical constant was 2.02×10-7 g/?h·mg?.?2?Eectroless copper plating on kraft paper substrate with sodium alginate was developed.Results showed that the sodium alginate chelated with divalent metals(Sn²⁺ and Pd²⁺),and then turned into the insoluble gel,and the divalent metals were coated on the surface of kraft paper.The chemisorption of catalytic metal improved affinity between polymers and metals and activated the chemistry performance.Electroless copper plating was successfully achieved and a tight,dense and continuous structure of copper-plated coating were obtained.The electromagnetic shielding effect of plated kraft paper was higher than 30 d B in a wide range of 0.5¹8 GHz.?3?The electroless nickel plating on PET surface by printing primer in combination with immersing in KH550 solution.It was found that the amine groups attached on the PET surface after pretreating,and then the nickel coating was deposited on the PET surface after electroless plating.The activation energy of reactions was 0.18 e V.The preferential orientation of the coatings changed from?200?plane to?111?plane,the surface electrical resistivity of nickel coating was reduced from 12.4 ?·cm to 0.2 ?·cm,and the thickness of plated coatings increased from 0.61 ?m to 2.58 ?m,when the deposited time increased from 1 min to 30 min.The average size integration of nickel particles was increased from 0.23 ?m to 0.92 ?m,the growth rate of plated nickel coating increased from 0.073 ?m/min to 0.132 ?m/min,and the surface electrical resistivity of plated nickel layers was reduced from 6235 ??cm to 0.63 ??cm with increased of bath p H value.The average size integration of neighbouring particles was increased from 0.24 ?m to 1.05 ?m and the surface electrical resistivity of plated nickel layers was reduced from 1110.3 ??cm to 0.13 ??cm,when the bath temperature increased from 20 ? to 100 ?.?4?The integration of physic-reunion nickel particle formed closely connected and evenly distributed nickel layers through lateral growth and vertical growth.The laterally grown were neighbouring particles squeezed and then merged into bigger nickel particles.The integration of the physic-reunion nickel particles would facilitate the formation of closely connected and evenly distributed nickel layers.The presence of some particles joined together to form bigger agglomerates.The vertically grown were the deposit of nickel atoms and the superimposition of multiple particles,which would facilitate the increase of thickness.However,squeezed nickel particles,large nickel-particle size and continuous nickel-particle boundaries combine to produce stress concentrations,as a result,the plated coatings formed cracks and then shed when the thickness of nickel coatings exceeded about 2.6 ?m.Increasing the heat-treatment temperature and actived time would facilitate the reduce of residual stress in the plated coatings.?5?The plated primer were obtained by emulsion polymerization?methyl methacrylate,butyl acrylate,acrylic acid and acrylamide?.Only the printed areas formed higher density of amine groups on the surface of polymer films.The amine groups serve as cores for chemisorption of Pd²⁺ ions via complexation.The selective,better adhesion and flexibility plated coating was obtained successfully by electroless nickel plating on polymer surface and inner wall of the through-hole modified with primer after the laser etched.The minimum width of nickel lines and spacing between copper lines are 250 ?m and 150 ?m,respectively.The residual compressive stress in the plated coatings was reduced and the 96% of dots passed the Scotch?-tape test when the plated coatings heat treatment at 120 ?.In addition,the region-selective electroless copper plating on the surface of Calcium carbonate filled polyehtylene sheets have been established based on printing primer with a pattern by screen printing.The copper patterning possessed excellent selectivity and flexibility.The higher coarse surface would improve adhesion of the plated coating.