s khajehpour - Islamic Azad University, Shiraz
g.r nejabat - Islamic Azad University, Shiraz

Polyolefins are one of the most popular classes of synthetic polymers, especially due to their useful combinations of properties, good availability and low price. Linear low-density polyethylene(LLDPE) is especially significant as it is widely used for many applications. This synthetic polymer is normally not biodegradable until it is degraded into low molecular mass fragments. In the present work various photo-catalytic additives especially titanium dioxide (TiO2) are used as prooxidants in order to make LLDPE degradable after working period. Anatase and rutile TiO2 are thermally blended withLLDPE. Results show that photo degradation leads to physical embrittlement of the blends and leaves a porous and mechanically weakened plastic. This will accelerate the final degradation of the polymer by diffusion of oxygen, moisture, and enzymes into the porous polymer matrix. The carbonyl index of the anatase TiO2 blended LLDPE films increases continuously over the irradiation period while theirtensile strength decreases. Also the films show a weight loss about 11-15 %.

Titanium dioxide, LLDPE, Photo-catalysts, Degradation