In situ formation of nanocomposites based on polyethylene and silica nanospheres

Abstract

Polyethylene nanocomposites containing silica nanospheres, synthesized by the sol-gel method, were produced via in situ polymerization. The silica nanospheres were added together with the catalytic system [metallocene catalyst and methylaluminoxane (MAO) as cocatalyst] directly to the reactor and used for the polymerization of ethylene. The polymerization activity increased slightly in the presence of 1 wt % silica nanospheres in comparison to the homogeneous polymerization sans filler. The Young's modulus of the nanocomposites increased 19-25% without a significant decrease in the elongation at break with respect to the neat polyethylene. The polymer particle morphology was also significantly improved with the incorporation of silica nanospheres. © 2010 Wiley Periodicals, Inc.