Novel Preparation of Polyethylene from Nano‐extrusion Polymerization Inside the Nanochannels of MCM‐41/MgCl₂/TiCl₄ Catalysts

The MCM‐41 and SiO₂ supported TiCl₄ and TiCl₄/MgCl₂ catalysts with different molar ratios of Mg/Ti were synthesized and used for ethylene polymerization under atmospheric pressure. The nanochannels of MCM‐41 serve as nanoscale polymerization reactor and the polyethylene nanofibers were extruded during the reaction. The nanofibers were observed in SEM micrographs of resulting polyethylene. The effect of MgCl₂ on catalytic activity and thermal properties of resulting polyethylene is investigated too. In the presence of MgCl₂, the catalytic activity increased and more crystalline polyethylene with higher melting points were formed. However, no fibers could be observed in the polyethylene prepared by SiO₂ supported catalysts.

Keywords:

• polyethylene nanofiber
• nano‐extrusion polymerization
• Ziegler‐Natta catalyst
• atmospheric pressure

5 Acknowledgment

We would like to thank the Center of Excellence for Chemical Engineering Processes at Tarbiat Modares University for the financial support of this project.