Polymer, chemical physics colloidal metal particles

The electrochemical and electroflotation methods are widely used to prepare of chemisorbed macromolecules bound to colloidal metal particles generated in situ. Electrochemical polymerization reactions are heterogeneous They are initiated on the electrode surface, while other stages (chain growth or termination) occm, as a rule, in the liquid phase. The yield of a polymer depends on the chemical and physical nature of the electrodes and their surface, electrode overvoltage, potential rmder which the reaction occurs, and electrical current density. The nature of the electrode material (metals or alloys, thin metallic coats, etc.) determines the characteristics of electron-transfer initiation and polymerization. Direct electron transfer between the electrode and monomer, cathodic deposition, and anodic solubilization of metals are optimum for electrochemical polymerization. Metal salts are the precursors of nanoparticles, which may act as specific electrochemical activators. Nanoparticles can influence activations through direct chemical binding to the monomer and by virtue of transfer, decomposition, or catalytic effects. Nonetheless, electrochemical polymerization has found only limited use in the preparation of polymer-immobilized nanoparticles. 

Metal clusters and colloids cannot be isolated in an unprotected form, as coalescence processes set in immediately by contact between particles to give amorphous or polycrystalline powders. Therefore, colloids have always been used in highly diluted dispersions, in polymers or in matrices [1]. Clusters are well known as stable compounds if they are protected by a shell of appropriate ligands. To make colloids available as isolable molecules (e. g. for homogenous catalysts), one developed a method to stabilize them by a ligand shell similar to that of clusters [2-4]. Colloids thus became applicable for numerous chemical and physical investigations [2, 5]. Even bimetallic particles have been stabilized and made useful in various practical applications [5]. 

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