Production and characterization of UHMWPE/fumed silica nanocomposites

Ramazani, A ; Sharif University of Technology | 2012

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  1. Type of Document: Article
  2. DOI: 10.1002/pc.22323
  3. Publisher: Wiley , 2012
  4. Abstract:
  5. Ultrahigh-molecular-weight polyethylene (UHMWPE)/fumed silica nanocomposites were prepared via in situ polymerization using a bi-supported Ziegler-Natta catalytic system. Nanocomposites with different nanoparticle weight fractions were produced in order to investigate the effect of fumed silica on thermal and mechanical properties of UHMWPE/fumed silica nanocomposites. The viscosity average molecular weight (M) of all samples including pure UHMWPE as the reference sample and nanocomposites were measured. Scanning electron microscope (SEM) images showed the homogenous dispersion of nanoparticles throughout the UHMWPE matrix while no nanoparticle cluster has been formed. Crystallization behavior of nanocomposites was investigated by differential scanning calorimetry (DSC), which showed a slight increase in melting temperature by enhancing the nanoparticle concentration while no significant change was observed in the crystallization temperature as the fumed silica concentration enhanced. The improvement in all thermal stability parameters was recorded by thermogravimetric analysis (TGA). Besides, via tensile testing, it was confirmed that addition of nanoparticles caused considerable improvement in such mechanical properties as Young's modulus, yield stress, and tensile strength of samples while the elongation at break declined by addition of more nanoparticles
  6. Keywords:
  7. Catalytic system ; Crystallization behavior ; Crystallization temperature ; Elongation at break ; Fumed silicas ; In-situ polymerization ; Nanoparticle clusters ; Nanoparticle concentrations ; Silica nanocomposites ; Stability parameters ; Thermal and mechanical properties ; Viscosity average molecular weight ; Weight fractions ; Young's Modulus ; Ziegler-Natta ; Differential scanning calorimetry ; Nanoparticles ; Scanning electron microscopy ; Silica ; Tensile testing ; Thermogravimetric analysis ; Yield stress ; Nanocomposites
  8. Source: Polymer Composites ; Volume 33, Issue 10 , 2012 , Pages 1858-1864 ; 02728397 (ISSN)
  9. URL: http://onlinelibrary.wiley.com/doi/10.1002/pc.22323/abstract;jsessionid=282223DC138EA7F2FAC61A565A668300.f01t01