Structural and adhesion properties of waterborne polyurethane adhesives containing nanosilica dispersion obtained with different physical mixing procedures

Nanosilica dispersion was added to waterborne polyurethane by using three different physical mixing procedures differing in the flow regime (tangential, laminar, radial) and stirring rate (300–2400 rpm). The influence of procedure on structural, thermal, rheological, mechanical, surface adhesion properties polyurethanes (PUs) containing 1 wt% nanosilica evaluated. functionalized with acrylic moieties showed high tension negative Z potential values. PU + blend made higher shear laminar homogeneous particles greater extent intercalation between soft segments polyurethane, this led thermal stability. Unexpectedly, better matrix decreased wettability materials due migration from surface. As a consequence, decrease final T-peel strength found. However, single lap-shear did not change adding because scarce improvement mechanical materials.