Strong decrease in viscosity of nanoparticle-filled polymer melts through selective adsorption

The melt viscosity of poly( propylene) is found to reduce dramatically through the addition of a minute amount of silica nanoparticles. We attribute this unique effect to selective adsorption of high molar mass polymer chains'' on the surface of the nanofillers. This represents a paradigm shift regarding commonly accepted relations between the molar mass and viscosity of molten polymers. This strong viscosity decrease provides major advantages for polymer processing, and materials with improved properties are obtained.