Evaluation of the effect of plasma treatment on the surface of green polyethylene and vermiculite clay films

ABSTRACT Green Polyethylene (PE) is a synthetic polymer that has low surface energy, which results in poor adhesion properties. This factor causes some problems regarding the practical applications of polymers, such as poor adherence of printing inks, coatings, adhesives and metals to the surface of the polymer, among others. One way to alter this property is by applying a plasma treatment. In this sense, the objective of this work was to prepare, by flat extrusion, biocomposite films with Green PE matrix (PEPURO) and load of Expanded Vermiculite Clay (VMT) in the 1% content. The films were treated by plasma under two different conditions: under O2 atmosphere (C1); (Ar/H2) and a subsequent treatment by plasma under O2 (C2) atmosphere. The results indicated that the plasma treatments and the incorporation of VMT increased the hydrophilicity of the films, and the application of condition 2 (C2) was shown more efficiently. The untreated PEPURO presented a significant reduction of maximum tensile strength with the insertion of VMT, already with the application of treatments (C1 and C2) the resistance values were higher. In relation to the roughness it was possible to verify that the application of the plasma increased the surface roughness of the samples. These results indicated that increased hydrophilicity and roughness resulted in a significant increase in the interaction of fluids with the surface and also improvement of the adhesive characteristics of the polymer.