Enhancement of mechanical properties of high modulus polypropylene grade for multilayer sewage pipes applications

Helena Khoury Moussa; Georges Challita; Houssem Badreddine; Guillaume Montay; Bruno Guelorget; Thomas Vallon; Wadih Yared; Marwan Abi Rizk; Akram Alhussein

arXiv · 2510.15415

Enhancement of mechanical properties of high modulus polypropylene grade for multilayer sewage pipes applications

Helena Khoury Moussa·Georges Challita·Houssem Badreddine·Guillaume Montay·Bruno Guelorget·Thomas Vallon·Wadih Yared·Marwan Abi Rizk·Akram Alhussein

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Abstract

Advances in technology have provided fresh generations of stiff polypropylene block copolymers for gravity sewerage applications. The aim of this study is to further enhance the stiffness of these materials through the incorporation of inorganic fillers. In this study, three talc filled PP and one glass fiber filled PP composites were characterized in order to be used as a middle layer in a three-layer sewage pipe. The obtained results showed an increase of approximately more than 100% and 250% in tensile and flexural moduli by the use of 30%--50___wt% talc-filled PP and 30___wt.% glass fiber-filled PP, respectively. This high increase in the rigidity of the material would allow manufacturing pipes with improving ring stiffness. Composites filled with 30___wt% talc or glass fiber showed good filler-matrix interaction and good filler distribution and dispersion. However, reduced filler-matrix interaction was observed in the case of the composite filled with 50___wt% talc. In addition, the use of Differential Scanning Calorimetry analysis revealed that the addition of fillers enhanced the crystallization temperature of the polypropylene matrix. Furthermore, Thermogravimetric Analysis showed that the high modulus PP grade retained its thermal stability in the various composites.

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Helena Khoury Moussa, Georges Challita, Houssem Badreddine, Guillaume Montay, Bruno Guelorget, Thomas Vallon, Wadih Yared, Marwan Abi Rizk, Akram Alhussein. 2025-10-17. Enhancement of mechanical properties of high modulus polypropylene grade for multilayer sewage pipes applications. https://arxiv.org/abs/2510.15415

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