The Effect of Co-monomer Type on the Mechanical and Thermal Properties of Metallocene and Conventional LLDPEs

✍ Scribed by Walker, S. ;Mcnally, G.M. ;Martin, P.J.

• Publisher: Curtin University of Technology
• Year: 2008
• Tongue: English
• Weight: 605 KB
• Volume: 12
• Category: Article
• ISSN: 0969-1855
• DOI: 10.1002/apj.5500120106

✦ Synopsis

Abstract

A range of metallocene and conventional linear low‐density polyethylenes (LLDPEs), with different material properties, were prepared by injection moulding. An assessment of the effect of cooling rate and polymer properties on the mechanical performance of the specimens was conducted to establish any significant correlations. Tensile results showed that hexane‐based metallocene (m)LLPDEs exhibited higher elongation to break while the Young's modulus of the materials was found to be more influenced by density. Impact results demonstrated that mLLDPEs have superior impact strength at room temperature over conventional LLDPEs. Rheological studies of the materials under high shear rates experienced in injection moulding, were performed to determine flow characteristics of the materials. Differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) were used to study the influence of the co‐monomer type and degree of branching on the properties of the materials.