Evaluation of the crystallization kinetics and melting of polypropylene and metallocene-prepared polyethylene blends

✍ Scribed by Mohammad Razavi-Nouri; James N. Hay

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 143 KB
• Volume: 104
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.25638

✦ Synopsis

Abstract

The kinetics of the isothermal crystallization of a polypropylene (PP) random copolymer containing 5 mol % ethylene, a metallocene linear low‐density polyethylene (m‐LLDPE) with 3.3 mol % hexene‐1 as a comonomer, and three blends were studied with differential scanning calorimetry at temperatures sufficiently high to prevent any crystallization of m‐LLDPE. The analysis was carried out with the Avrami equation. The overall crystallization rate and the equilibrium melting temperature of the PP copolymer decreased with increasing amounts of m‐LLDPE in the blends. The former was attributed to the effect of m‐LLDPE in reducing the number of primary nuclei, and the latter was attributed to a lowering of the fold surface energy due to the limited partial miscibility of the blend components. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 634–640, 2007