Functionalizing face masks with natural clays: preliminary results

Abstract

The materials used in the fabrication of standard, three-layered surgical masks are functionalized by the incorporation of Cuban natural clay with potential microbicidal properties. Different treatments involving aqueous solutions of bentonite (Bent) clay and small amounts of a cationic surfactant are studied. Optical microscopy indicates that the clay particles are effectively adhered to the fibers forming the mask layers. The capacity of the materials to block ballistic droplets showed to be very high for the external and medium layers of a surgical mask both before and after functionalization. However, functionalization demonstrated to increase the blocking capacity of the material in the inner layer, i.e., that closer to the user face.