Investigation on the Effect of Physical properties on Corrosion Resistance and Adhesion of Latex paints Applied on ferrous substrates

The sipomer Pam 100(sp100) monomer is introduced by Rodia Company by the aim of adhesion enhancement of lattices. In this research, pure acrylic latex is synthesized. Sp100 was included in the range of 1-10% by the weight of the monomers. The other monomers were methyl methacrylate (MMA), butyl acrylate(BA) and methacrylic acid(MAA). Calculated Tg, according the Fox equation, was 20 °C. Optimum content of sp100 was obtained at 5%. In the next step the Sp100 content retained fixed on 5%, and by varying the MMA/BA ratio, the lattices with Tg’s-10 to 40 were prepared, and the role of Tg on adhesion and corrosion resistance was studied. The best result of adhesion was obtained at Tg 30°C; and the least corrosion occurred on 0°C.In the second part of this research the synthesized lattices were neutralizeaed with different bases:NaOH, ammonia, amine and compared with acid form.The best adhesion was obtained from NaOH and acid form and the sample which neutralized with ammonia has the least corrosion. In the next step the role of viscosity was studied but the effect of viscosity changes on adhesion was negligible.In the other hand the sample with low viscosity had better corrosion protection. Adhesion evaluated by cross cut test and corrosion was studied by salt spray under the standards ASTM D3359 and ASTM D714 respectively.

Keywords:

Sipomer pam 100 , corrosion , Adhesion , Emulsion Polymerization