Melt Strength Behaviour of Polypropylenes
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A. Ghijsels
Abstract
Melt strength data are presented for polypropylenes, differing widely in molecular weight and molecular weight distribution. Melt strength was assessed from uniaxial tensile experiments with a Rheotens apparatus. A new measuring procedure was applied by performing the stretching in front of the take-up wheels of the Rheotens instead of in between the wheels. It is shown that the melt strength of polypropylene is solely determined by its weight average molecular weight. At a given melt index level, narrow molecular weight distribution (controlled rheology) polypropylenes have a lower melt strength than the wider distribution reactor grades. At high temperatures, the melt strength follows an Arrhenius type temperature dependence, while at the lower test temperatures the melt strength of polypropylenes having a wider distribution is increased by flow-induced crystallisation.
© 1994, Carl Hanser Verlag, Munich
Artikel in diesem Heft
- Contents
- Contents
- Editorial
- Tenth in a Series: Fried. Krupp: Pioneer Integrated Steel and Processing Machinery Manufacturer. Part 1. Essen, Magdeburg and Harburg (1812–1960)
- Internal Mixers
- Finite Element Modelling of Non-isothermal Viscometric Flows in Rubber Mixing
- Screw Extrusion and Mixing
- The Optimisation of Masterbatch Formulations for Use in Single Screw Machines
- Morphological Changes of a Polymer Blend into a Twin-Screw Extruder
- An In-line Melt Rheometer for Molten Plastics
- Selecting Continuous Compounding Equipment Based on Process Considerations
- Reactive Processing
- Peroxide Induced and Thermal Degradation of Polypropylene
- Reactive Blending of Polyamide 6 and Polycarbonate
- Modification of Polypropylene by Maleic Anhydride
- Fibers and Films
- Melt Strength Behaviour of Polypropylenes
- Molding
- Multilayer Injection Moulding
- Miscibility and Mechanical Properties of Poly(ether imide)/Liquid Crystalline Poly(ester imide) Blends
- The Effects of Recycling and Degradation on Parison Extrusion
- Modeling and Simulation of High Reynolds' Number Flows During Reaction Injection Mold Filling
Artikel in diesem Heft
- Contents
- Contents
- Editorial
- Tenth in a Series: Fried. Krupp: Pioneer Integrated Steel and Processing Machinery Manufacturer. Part 1. Essen, Magdeburg and Harburg (1812–1960)
- Internal Mixers
- Finite Element Modelling of Non-isothermal Viscometric Flows in Rubber Mixing
- Screw Extrusion and Mixing
- The Optimisation of Masterbatch Formulations for Use in Single Screw Machines
- Morphological Changes of a Polymer Blend into a Twin-Screw Extruder
- An In-line Melt Rheometer for Molten Plastics
- Selecting Continuous Compounding Equipment Based on Process Considerations
- Reactive Processing
- Peroxide Induced and Thermal Degradation of Polypropylene
- Reactive Blending of Polyamide 6 and Polycarbonate
- Modification of Polypropylene by Maleic Anhydride
- Fibers and Films
- Melt Strength Behaviour of Polypropylenes
- Molding
- Multilayer Injection Moulding
- Miscibility and Mechanical Properties of Poly(ether imide)/Liquid Crystalline Poly(ester imide) Blends
- The Effects of Recycling and Degradation on Parison Extrusion
- Modeling and Simulation of High Reynolds' Number Flows During Reaction Injection Mold Filling
