Metallization of plastics

It is interesting to conclude this section with an example that, in a sense, brings the chapter full circle. The metallization of plastic materials used as metal substitutes is a process with actual and future commercial potential. Usually, plastics are plated after appropriate sensitization by an electroless process which involves reduction of metal ions (e.g. Ni2+, Cu2+) by chemical rather than electrical means.19 There seems no reason why the reducing agent should not be incorporated in the polymer and Murray and his collaborators101 have demonstrated that copper, silver, cobalt and nickel may each be electrodeposited on to films of [poly-Ru(bipy)2(4-vinylpyridine)2]2+ coated on to platinum electrodes. The metal reductions are mediated by the Ru1 and Ru° states of the polymer. 

The metallizing of plastics offers new scope for design engineers, extending the opportunity to make improvements and to replace components made previously in other materials (like glass, or ferrous or non-ferrous metals). On the other hand, there are also certain new problems, which must be considered and overcome if work of satisfactory quality is to be achieved. 

The authors wish to thank B. R. Karas and E. J. Lamby for their inputs to the metallization of plastics as well as the metallography, XPS (M. Burrell, J. Chera) and SEM (L. King) analytical services. 

M. Shalkauskas, A. Vashkialis, Electroless Metallization of Plastics (in Russian), Leningrad, ed. "Khimia", 144 (1985). 

SD is routinely used to deposit thin films and has proven benefits from economies of scale in the metallization of plastics. The technique has already been used to create enhanced and unique MEAs for H2 -air proton exchange membrane fuel cell (PEMFC) systems. In this project, JPL is pursuing the use of SD to create DMFC membrane electrode assembly structures with highly electro-active catalyst layers that will reduce the amount and cost of the Pt-alloy catalyst at the fuel cell anode. 

The thermoplastics used for corrosion resistance are fluorocarbons, acrylics, nylon, chlorinated polyether, polyethylenes, polypropylenes, polystyrence, and poly (vinyl chloride) important thermosetters used in this field are epoxies, phenolics, polyesters, sflicones, and ureas. AH plastics show useful physical properties. One drawback in the use of plastics is their limited tolerance to temperature. Fluorocarbons are the noble metals of plastics they are corrosion resistant to practicaHy all environments up to 290 C. 

Designing of OrganometalHcs for Vapor Phase Metallization of Plastics... 

Shalkauskas, M. and Vashkalis, A. Chemical Metallization of Plastics. Chemistry, (Russ) (1977). 

See also electroless and electrolytic-plated plastic metallization of plastic. 

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