Influence of multiwall carbon nanotubes on morphological and structural changes during UV irradiation of syndiotactic polypropylene films.

The effect of UV irradiation on the morphology and structure of syndiotactic polypropylene (sPP) is investigated both for pure films and those filled with multiwall carbon nanotubes (MWCNTs). UV treatment causes a structural reorganization of pure sPP films. It seems that the incorporation of MWCNTs has a strong stabilizing effect, with nanotubes acting as a limiter of the UV-induced chain breakage, especially when a good dispersion of carbon nanotubes in the polymer is achieved. The incorporation of MWCNTs introduces a high concentration of defects in the crystal structure of sPP, which limits the UV-induced growth of crystallites, and prevents the development and propagation of cracks caused by UV irradiation. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 The study of the degradation by UV irradiation of polymeric composites is necessary to understand the nanofiller influence on durability of the material. Investigated here is the effect of UV irradiation on the morphology and structure of syndiotactic polypropylene both for pure films and those filled with multiwall carbon nanotubes (MWCNTs). UV treatment of pure (unfilled) polypropylene films causes a complex structural reorganization of chain conformations. A strong stabilizing effect against UV irradiation is achieved by incorporating MWCNTs in the same polypropylene films (filled samples). Copyright © 2012 Wiley Periodicals, Inc