Iranian Polymer Journal

, Volume 27, Issue 5, pp 287–296 | Cite as

Tensile, thermal, flammability and morphological properties of sepiolite filled ethylene propylene diene monomer (EDPM) rubber composites

  • Nurul Aizan Mohd Zaini
  • Hanafi Ismail
  • Arjulizan Rusli
Original Research


The effect of sepiolite loading content on the curing characteristics, tensile mechanical, thermal, swelling, flammability and morphological properties of sepiolite-filled ethylene propylene diene monomer (EPDM) composites was investigated. The composites were prepared with sepiolite loadings of 0–70 part per hundred (phr) of rubber using a two-roll mill. The results highlighted the improvement in the tensile properties and cross-link density values peaked at 60 phr of sepiolite loading. The scorch time, curing time, swelling percentage, and linear burning rate of the composites decreased with an increase in sepiolite loading. Thermogravimetric analysis showed an increasing trend with increase in sepiolite loading. The temperatures corresponding to 5, 25 and 50% weight loss (T5wt%, T25wt% and T50wt%) and the percentage of char residue gradually increased with increase in sepiolite loading. The homogenous dispersion of the sepiolite particles in the EPDM matrix and the formation of zigzag structures, especially at 60 phr, were the main reasons of the improvement of mechanical properties which were confirmed by the morphological studies. The formation of a protective layer, which acted as a barrier against heat transfer into the deeper layers, enhanced the flammability resistance of the composites. Notably, the EPDM filled with 60 phr sepiolite exhibited excellent performance in the aspects of mechanical, thermal stability and flammability properties and resistance towards swelling.


Sepiolite Cure characteristics Tensile properties Swelling behaviour Thermal stability Flammability 



The authors would like to thank all levels of staff in the Department of Materials and Mineral Resources Engineering, Universiti Sains Malaysia (USM). They provided a wide variety of unconditional facilities to make this research success. One of the authors is also deeply indebted to the Ministry of Higher Education of Malaysia (KPT(BS)821115065540) and Universiti Teknologi Mara (UiTM) (600-BPD (PKH.1/2/9946) for providing funding to conduct this research.


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Copyright information

© Iran Polymer and Petrochemical Institute 2018

Authors and Affiliations

  • Nurul Aizan Mohd Zaini
    • 1
    • 2
  • Hanafi Ismail
    • 1
  • Arjulizan Rusli
    • 1
  1. 1.School of Materials and Mineral Resources Engineering, Engineering CampusUniversiti Sains MalaysiaNibong TebalMalaysia
  2. 2.Faculty of Applied SciencesUniversiti Teknologi Mara PerlisArauMalaysia

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