Preparation and characterization of electroless nickel-coated cellulose fibres
The aim of this project was to fabricate electroless nickel-coated cellulose fibres. Ultimately, these nickel-coated cellulose fibres will be used to develop a cost-effective polymer composite for electromagnetic interference (EMI) shielding and/or electrostatic discharge (ESD) applications. An attempt has been made to impart electrical conductivity onto cellulose fibres via an electroless nickel plating process. The aim was to achieve a homogeneous, continuous layer of Ni on the cellulose fibres, and the plating conditions were optimized to achieve this. The relationship between the coating morphology and the performance of the coated fibre was also of interest. Testing was carried out using cellulose filter paper and then loose cellulose fibres. Scanning electron microscopic (SEM) images of nickel-coated filter paper showed that nickel particles are bonded to the cellulose fibres. The coating appeared more compacted and continuous as plating time increased, corresponding to lower surface resistivity. This observation suggested a correlation between morphology and electrical conductivity of the coating. For nickel-coated cellulose fibres, after optimization of plating conditions, a uniform deposition of nickel particles around the cellulose surfaces was confirmed by SEM images. EDS and XRD results confirmed similar coating could be produced on filter paper and cellulose fibres. SEM images of cross-sectioned nickel-coated cellulose fibres illustrated nickel particles had penetrated into the inner walls of the cellulose fibres. This impregnation of the fibres should act to increase the bonding between nickel coating and cellulose fibres. These nickel-impregnated cellulose fibres could now be incorporated into a polymer matrix to create an electrically conducting composite with the right processing parameters.
Conductive Polymers and Plastics: In Industrial Applications
This book is a collection of papers by individuals in industry and academia on research and application development of conductive polymers and plastics. Conductive plastics are positioned to play an increasingly important role in affairs of mankind, specifically in the area of electrical and electronic conductivity. While general knowledge about conductive polymers and plastics has been available for many years, a true understanding of their application has only taken place in the last 3 to 4 years. This is attributed to advances in materials and processing techniques. Engineers have only begun to explore the design freedom and economic benefits of specifying conductive polymers and plastics in industrial and business applications. This book is a key reference and guide to the use of conductive polymers and plastics. It is a summary of existing technologies, but also a look at future possibilities.
Adsorption Promotion of Ag Nanoparticle Using Cationic Surfactants and Polyelectrolytes for Electroless Cu Plating Catalysts
Ag nanoparticles were adsorbed onto epoxy and fluorine-doped tin oxide (FTO) glass substrates by dipping them into a Ag nanoparticle colloidal solution to catalyze the substrate for electroless Cu plating. Before the Ag nanoparticle adsorption, the substrates were conditioned with either a cationic surfactant, stearyltrimethylammonium chloride (STAC), or a cationic polyelectrolyte, poly(diallyldimethylammonium chloride) (PDDA), both having quaternary amine headgroups. The adsorbed Ag nanoparticles catalyzed the HCHO oxidation reaction, thereby allowing the electroless Cu deposition reaction to start. For both the epoxy and the FTO glass substrates, conditioning with the concentrated PDDA solution having a 100 × 10 -3 mol L -1 quaternary amine concentration was the most effective in producing the largest amounts of Ag nanoparticles to be adsorbed and in providing the fastest initial deposition rate of the electroless Cu plating. When the diluted conditioners were used, a comparison between the diluted STAC and PDDA showed that STAC was the more effective conditioner for the epoxy substrates, while PDDA was more effective for the FTO glass substrates. The effectiveness of STAC was attributed to the strong hydrophobic interaction with the epoxy substrate surface. However, the effectiveness of PDDA was attributed to the strong electrostatic interaction with the FTO glass surface.