Polymer nanocomposites in corrosion control

Key words anticorrosion, organophilic clay, polymer/clay nanocomposites, electroactive polymer/clay nanocomposites, gas barrier. 

Metals and alloys The most common method for preventing corrosion is the selection of the proper metal or alloy for a particnlar corrosive service (Tiwari et al, 2010 Custodio et al., 2010). 

Metal purification The corrosion resistance of a pnre metal is usually better than that of one containing impurities or small amounts of other elements. However, pure metals are usually expensive and are relatively soft and weak. In general, pure metals are used in relatively few, special cases (Tiwari et al., 2001 Custodio et al., 2010). 

Inhibitors An inhibitor is a substance that, when added in srrtall concentrations to an environment, decreases the corrosion rate. In a serrse, an inhibitor can be considered a retarding catalyst. There are nirmeroirs irrhibitor types and compositions. Most inhibitors have been developed by empirical experimentation and many are proprietary in nafttre thus their composition is not disclosed. Inhibition is not completely rmderstood for these reasons, but it is possible to classify inhibitors according to their mechanism and composition (Tiwari et al, 2001 Custodio etal, 2010 Rosenfeld, 1981). 

Cathodic protection Cathodic protection was employed before electrochemistry had been developed. Htrmphrey Davy used cathodic protection on British naval ships in 1824. The principles of cathodic protection may be explained by considering the corrosion of atypical metal in an acid environment. Electrochemical reactions include the dissolution of the metal and the evolution of hydrogen gas  

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