Studies on effect of nanoclay on the properties of thermally sprayable EVA and EVAI coatings

Dispersion of nanoclay (NC) in polymer blend system is governed by the sequence of addition of different ingredients. In the present work nanoclay was added in different sequences to blend composition such as ethylene vinyl acetate (EVA)/low density polyethylene (LDPE) and ethylene vinyl alcohol (EVAl)/LDPE in internal mixer to get nanocomposite. It was found that sequential addition of individual polymers and nanoclay influenced mechanical properties of resulting composites. Blending sequence of PE/NC/EVA and PE/NC/EVAl gave best mechanical properties. After optimization of addition sequence, concentration of nanoclay was varied from 1 to 8% by weight in the polymer blend. The resulting composites were evaluated in terms of their mechanical properties, dispersion characteristics (XRD), water vapor transmission rate (WVTR) and water absorption (Wa). Nanocomposite containing EVA/LDPE blend with 4% nanoclay showed optimum properties. The optimized composition was applied on grit blasted mild steel specimens by flame spray technique. The coated specimens were evaluated for adhesion strength, abrasion resistance and resistance to corrosion properties.