Iranian Polymer Journal

, Volume 27, Issue 9, pp 701–708 | Cite as

A disentangled state using TiCl4/MgCl2 catalyst: a case study of polyethylene

  • Amin Heidari
  • Hamid Zarghami
  • Saeid TalebiEmail author
  • Mostafa Rezaei
Original Research


Fully entangled morphology which is usually expected for polyethylene produced using Ziegler–Natta (ZN) catalyst is due to the presence of active sites crowded on catalyst’s support surface as well as within its volume. In this research, the feasibility of producing disentangled, more precisely less entangled, polyethylene using a heterogeneous ZN catalyst supported on magnesium chloride, TiCl4/MgCl2, is introduced. Polymerization was carried out at rather low temperature and pressure, and the nascent polymer was characterized to investigate its entanglement state. The rheological measurements, at small amplitude oscillating in the time sweep mode, exhibited a rather good modulus build-up, demonstrating the nascent polymer in its dis(less)-entangled state. Tape and film samples were prepared from the synthesized polyethylene below its melting point to keep the morphology untapped. The solid-state drawability test was performed on the samples at 100 °C showing its improved drawability. Thus, it could be concluded that the polyethylene synthesized at rather low temperature of 0 °C and longer polymerization time was in disentangled state. Furthermore, a rheometrical analysis in frequency mode was used to estimate the molecular weight and molecular weight distribution of the synthesized polyethylene qualitatively. From X-ray diffraction patterns the existence of a small amount of hexagonal phase in the nascent polymer could be detected, which may be due to the formation of extended chains during polymerization.


UHMWPE Disentangled state Solid-state drawability Ziegler–Natta catalyst Mechanical properties 

Supplementary material

13726_2018_648_MOESM1_ESM.docx (551 kb)
Supplementary material 1 (DOCX 551 KB)


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Copyright information

© Iran Polymer and Petrochemical Institute 2018

Authors and Affiliations

  • Amin Heidari
    • 1
  • Hamid Zarghami
    • 1
  • Saeid Talebi
    • 1
    Email author
  • Mostafa Rezaei
    • 1
  1. 1.Polymer Engineering Department, Institute of Polymeric MaterialsSahand University of TechnologyTabrizIran

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