Brittle Melt Rupture Phenomena in Polymer Processing
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A. Ghijsels
Abstract
In this contribution the various rupture mechanisms which can occur during the elongation of polymer melts will be briefly reviewed, with the focus on the cohesive brittle melt rupture. Observations of melt rupture phenomena during polymer processing operations will be discussed. The occurrence of brittle melt rupture is characterised by a constant value of the rupture stress in the order of 1 MPa. Published rupture stress data on various polymer melts are critically discussed, in particular those on polyethylenes and other polyolefins. Using the Rheotens technique a newly developed method will be described to measure the melt rupture stress of polypropylene (PP) melts. The measurement of the rupture stress of PP melts is hampered by the occurrence of the instability draw resonance. This problem was overcome by applying more pronounced cooling conditions. Initial data on the rupture stress of PP melts will be presented. It is shown that the rupture stress of PP melts is not a constant but increases with increasing molecular weight.
© 1997, Carl Hanser Verlag, Munich
Artikel in diesem Heft
- Contents
- Contents
- Editorial
- Third in a Series: Pioneers of Polymer Processing: Charles Goodyear
- Screw Extrusion/Mixing
- Chaotic Features of Flow in Polymer Processing Equipment-Relevance to Distributive Mixing
- Influence of Design on Mixing Efficiency in a Variable Intermeshing Clearance Mixer
- Simulation of Non-Isothermal Flow in a Modular Buss Kneader and Comparison with Experiment
- Rheological Behaviour of LLDPE/LDPE Blends under Elongational Deformation
- Effect of Compounding Conditions on Mechanical Properties of Glass Fiber-Reinforced Polyamide-6
- Die Extrusion
- A New Approach to Simulation of Die Flow which Incorporates the Extruder and Rotating Screw Tips in the Analysis
- New Aspects Concerning the Design of Coathanger Dies
- Film
- On-Line Birefringence Measurement in Film Blowing of a Linear Low Density Polyethylene
- Brittle Melt Rupture Phenomena in Polymer Processing
- Moulding
- Injection Molding of LDPE/BaSO4 Blends
- An Experimental Study of Rotational Molding of Polypropylene/Polyethylene Copolymers
- Determination of the Inter-Relationships Between Processing Conditions and Properties of an Injection Molded Silicone Ring Using an Experimental Design
- Numerical Simulation of the Flow and Fiber Orientation in Reinforced Thermoplastic Injection Molded Products
- Wide-Angle X-Ray, Densitometric and Microscopical Studies on Injection Molded Polypropylene Disks
Artikel in diesem Heft
- Contents
- Contents
- Editorial
- Third in a Series: Pioneers of Polymer Processing: Charles Goodyear
- Screw Extrusion/Mixing
- Chaotic Features of Flow in Polymer Processing Equipment-Relevance to Distributive Mixing
- Influence of Design on Mixing Efficiency in a Variable Intermeshing Clearance Mixer
- Simulation of Non-Isothermal Flow in a Modular Buss Kneader and Comparison with Experiment
- Rheological Behaviour of LLDPE/LDPE Blends under Elongational Deformation
- Effect of Compounding Conditions on Mechanical Properties of Glass Fiber-Reinforced Polyamide-6
- Die Extrusion
- A New Approach to Simulation of Die Flow which Incorporates the Extruder and Rotating Screw Tips in the Analysis
- New Aspects Concerning the Design of Coathanger Dies
- Film
- On-Line Birefringence Measurement in Film Blowing of a Linear Low Density Polyethylene
- Brittle Melt Rupture Phenomena in Polymer Processing
- Moulding
- Injection Molding of LDPE/BaSO4 Blends
- An Experimental Study of Rotational Molding of Polypropylene/Polyethylene Copolymers
- Determination of the Inter-Relationships Between Processing Conditions and Properties of an Injection Molded Silicone Ring Using an Experimental Design
- Numerical Simulation of the Flow and Fiber Orientation in Reinforced Thermoplastic Injection Molded Products
- Wide-Angle X-Ray, Densitometric and Microscopical Studies on Injection Molded Polypropylene Disks
