Nanocomposites of silica reinforced polypropylene: Correlation between morphology and properties

Authors

  • Amira Bouaziz,

    1. Laboratoire d'Electrochimie et Environnement, ENIS-Sfax, Sfax, Tunisie
    2. INSA de Lyon, CNRS UMR 5223, Ingénierie des Matériaux Polymères, Villeurbanne, Lyon, France
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  • Mohamed Jaziri,

    1. Laboratoire d'Electrochimie et Environnement, ENIS-Sfax, Sfax, Tunisie
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  • Florent Dalmas,

    1. ICMPE (Institut de Chimie et des Matériaux Paris-Est), UMR 7182 CNRS/Université Paris-Est Créteil, Thiais, France
    Current affiliation:
    1. Florent Dalmas is currently at MATEIS (Matériaux: Engénierie et Science), UMR 5510 CNRS/INSA de Lyon, Bât. B. Pascal, Villeurbanne cedex, France
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  • Valerie Massardier

    Corresponding author
    1. INSA de Lyon, CNRS UMR 5223, Ingénierie des Matériaux Polymères, Villeurbanne, Lyon, France
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Abstract

Polypropylene/fumed hydrophilic silica nanocomposites were prepared via melt mixing method using a single-screw extruder. Comparative study with and without compatibilizing copolymer agent (maleic anhydride grafted polypropylene: PP-g-AM) was conducted. The obtained results were interpreted in terms of silica nanoparticle–silica nanoparticle and silica nanoparticle-polymer interactions. These results have shown that the addition of nanofillers improves the properties of the nanocomposites. From transmission electron microscopy, it was found that agglomerations of silica particles into the PP matrix increased in average size with increasing silica contents, except in presence of the copolymer. Storage modulus values of the nanocomposites measured by dynamic mechanical thermal analysis were sensitive to the microstructure of the nanocomposites. Higher silica contents resulted in higher storage modulus, revealing that the material became stiffer. By adding the compatibilizer, a further increase of storage modulus was observed due to the finer dispersion of the filler in the matrix and the increased interfacial adhesion. Crystallization rates were found to increase with the increase of silica nanoparticles as well as PP-g-MA content. In addition, silica nanoparticles and the compatibilizing agent present centers of germination and nucleation of crystallites. Thus, the use of the coupling agent resulted in a further enhancement of mechanical properties of the nanocomposites due to the reduction of silica agglomeration. POLYM. ENG. SCI., 54:2187–2196, 2014. © 2013 Society of Plastics Engineers

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