Polyethylene-Waste Tire Dust Composites Via In Situ Polymerization

Polyethylene/waste tire dust (wtd) composites were ob- tained by an in situ polymerization technique. The surface of the wtd was modified with deposition of polyethylene by using plas- ma polymerization. Ethylene polymerization was carried out using bis(cyclopentadienyl) titanium dichloride (Cp2TiCl2) as homogeneous metallocene catalyst, while diethylaluminum chloride (deac), eth- ylaluminum sesquichloride (easc) and methyl aluminoxane (mao) were used as co-catalysts at two different (Al)/(Ti) molar ratio. The main characteristics of the obtained polyethylenes were determined by size exclusion chromatography, thermogravimetric analysis, dif- ferential scanning calorimetry and wide-angle X-ray diffraction. The results showed that by using easc and mao the highest catalytic activities were presented at a (Al)/(Ti) molar ratio of 9.17 and 18.33 respectively. Even though it was possible to obtain polyethylene using wtd (modified or unmodified) the catalytic activity was lower than in the case in which no wtd was added in ethylene polymerization. Scanning transmission electronic microscopy images evidenced that the original morphology of the polyethylenes was not modified by the presence of wtd.