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

ABSTRACT: The effect of UV irradiation on the morphologyand structure of syndiotactic polypropylene (sPP) is investi-gated both for pure films and those filled with multiwallcarbon nanotubes (MWCNTs). UV treatment causes a struc-tural reorganization of pure sPP films. It seems that theincorporation of MWCNTs has a strong stabilizing effect,with nanotubes acting as a limiter of the UV-induced chainbreakage, especially when a good dispersion of carbonnanotubes in the polymer is achieved. The incorporation ofMWCNTs introduces a high concentration of defects in thecrystal structure of sPP, which limits the UV-induced growthof crystallites, and prevents the development and propaga-tion of cracks caused by UV irradiation. V C 2012 Wiley Peri-odicals, Inc. J Polym Sci Part B: Polym Phys 50: 963–975,2012 KEYWORDS: atomic force microscopy; carbon nanotubes; com-posites; degradation; poly(propylene)INTRODUCTION Since Iijima’s landmark paper in 1991, 1 car-bon nanotubes (CNTs) have spurred many researchers ondeveloping advanced CNT composite materials to transfersome of their excellent physical properties

[1]  C. Naddeo,et al.  Structural and Morphological Changes during UV Irradiation of the Crystalline Helical Form of Syndiotactic Polypropylene , 2004 .

[2]  A. Rashidi,et al.  Rheological and Mechanical Characterization of Multi-Walled Carbon Nanotubes/Polypropylene Nanocomposites , 2008 .

[3]  I. Kinloch,et al.  Ultra-low electrical percolation threshold in carbon-nanotube-epoxy composites , 2003 .

[4]  J. Coleman,et al.  Small but strong: A review of the mechanical properties of carbon nanotube–polymer composites , 2006 .

[5]  Alexei P. Sokolov,et al.  Microscopic Mechanism of reinforcement in single-wall carbon nanotube/polypropylene nanocomposite , 2005 .

[6]  Structural and morphological changes during UV irradiation of the trans-planar form of syndiotactic polypropylene , 2008 .

[7]  C. A. Wilkie,et al.  The influence of carbon nanotubes, organically modified montmorillonites and layered double hydroxides on the thermal degradation and fire retardancy of polyethylene, ethylene-vinyl acetate copolymer and polystyrene , 2007 .

[8]  K. Shin,et al.  Radiation resistant polymer–carbon nanotube nanocomposite thin films , 2005 .

[9]  Jonathan N. Coleman,et al.  Mechanical Reinforcement of Polymers Using Carbon Nanotubes , 2006 .

[10]  P. Lamberti,et al.  Effect of functionalization on the thermo-mechanical and electrical behavior of multi-wall carbon nanotube/epoxy composites , 2011 .

[11]  M. Moniruzzaman,et al.  Polymer Nanocomposites Containing Carbon Nanotubes , 2006 .

[12]  C. Naddeo,et al.  Mechanical and barrier properties of epoxy resin filled with multi-walled carbon nanotubes , 2009 .

[13]  R. Andrews,et al.  Carbon nanotube polymer composites , 2004 .

[14]  V. Malatesta,et al.  Photo-oxidation behaviour of polyethylene/multi-wall carbon nanotube composite films , 2009 .

[15]  C. A. Hille,et al.  Effects of UV degradation on surface hydrophobicity, crack, and thickness of MWCNT-based nanocomposite coatings , 2011 .

[16]  H. Tadokoro.  Structure of crystalline polymers , 1979 .

[17]  E. Pavlidou,et al.  Effect of different nanoparticles on HDPE UV stability , 2011 .

[18]  N. S. Tomer,et al.  Nanoscale particles for polymer degradation and stabilization—Trends and future perspectives , 2009 .

[19]  T. Kashiwagi,et al.  Thermal Degradation and Flammability Properties of Poly(propylene)/Carbon Nanotube Composites , 2002 .

[20]  Liangchi Zhang,et al.  Fabrication and application of polymer composites comprising carbon nanotubes. , 2007, Recent patents on nanotechnology.

[21]  P. Dubois,et al.  Polymer/carbon nanotube nanocomposites: Influence of carbon nanotubes on EVA photodegradation , 2007 .

[22]  D. Bikiaris.  Microstructure and Properties of Polypropylene/Carbon Nanotube Nanocomposites , 2010, Materials.

[23]  G. Scott.  Introduction to the abiotic degradation of carbon chain polymers , 1995 .

[24]  S. Bocchini,et al.  Influence of MWNT on Polypropylene and Polyethylene Photooxidation , 2011 .

[25]  J. Verdu,et al.  Review: degradation-induced embrittlement in semi-crystalline polymers having their amorphous phase in rubbery state , 2008, Journal of Materials Science.

[26]  Q. Yuan,et al.  A mechanistic study of fire retardancy of carbon nanotube/ethylene vinyl acetate copolymers and their clay composites , 2005 .

[27]  K. Preston,et al.  Radical Reactions of C60 , 1991, Science.

[28]  C. Naddeo,et al.  Effect of carbon nanotubes on the photo-oxidative durability of syndiotactic polypropylene , 2010 .

[29]  F. Rugg,et al.  Infrared spectrophotometric studies on polyethylene. II. Oxidation , 1954 .

[30]  P. Lamberti,et al.  Dependence of electrical properties of polypropylene isomers on morphology and chain conformation , 2009 .

[31]  P. Lamberti,et al.  Cure behavior and physical properties of epoxy resin-filled with multiwalled carbon nanotubes. , 2010, Journal of nanoscience and nanotechnology.

[32]  S. Iijima.  Helical microtubules of graphitic carbon , 1991, Nature.

[33]  Yiu-Wing Mai,et al.  Dispersion and alignment of carbon nanotubes in polymer matrix: A review , 2005 .

[34]  J. Verdu,et al.  Embrittlement of polypropylene fibre during thermal oxidation , 2008 .