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Polytetrafluoroethylene Paste Extrusion: A Fibrillation Model and Its Relation to Mechanical Properties

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Published/Copyright: September 9, 2013
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International Polymer Processing
From the journal International Polymer Processing Volume 28 Issue 3

The effects of process conditions on fibrillation and mechanical properties of polytetrafluoroethylene (PTFE) paste extrudates have been studied using capillary rheometers having barrels of different diameter and equipped with capillary dies of various designs. The tensile strength of PTFE extrudates is measured as a function of apparent shear rate (flow rate), reduction ratio (cross sectional area of barrel to that of die), contraction angle, and diameter of the barrel. To describe the effects of die design on the quality of the final product, a basic phenomenological mathematical model has been developed. The model consists of a simple equation that explains fibril formation, due to the compression of PTFE resins, plus a kinetic equation, which is coupled with the “radial-flow” hypothesis to predict the structure and the tensile strength of extrudates. The model predictions are found to be consistent with tensile strength measurements and SEM micrographs of the PTFE extrudates.

3 Mail address: Savvas G. Hatzikiriakos, Department of Chemical and Biological Engineering, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada. E-mail:

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Received: 2012-11-27
Accepted: 2013-4-5
Published Online: 2013-09-09
Published in Print: 2013-07-01

© 2013, Carl Hanser Verlag, Munich

Articles in the same Issue

  1. Contents
  2. Contents
  3. Regular Contributed Articles
  4. Climatic Ageing of Components of Polymer Based Electrochromic Devices
  5. Previous Experimental Polymer Rheology Versus Flow Induced Crystallization
  6. Studies on the Effect of Pellet Size on Positive Conveying in Helically Grooved Single Screw Extruders
  7. Distortion of Interfaces in a Multilayer Polymer Co-extrusion Feedblock
  8. Preparation and Characterization of PES and PA Composite Membranes for Air Separation at Low Pressures
  9. Impact of Feed Opening Width and Position on PVC Extrusion Process Effectiveness
  10. Irradiation Strategy for Laser Transmission Welding of Thermoplastics Using High Brilliance Laser Source
  11. Polytetrafluoroethylene Paste Extrusion: A Fibrillation Model and Its Relation to Mechanical Properties
  12. Improving Weld Line Strength of Fiber Reinforced Plastics By Means of A “Flow Disruptor”
  13. Application of the Network Simulation Method to Flat Dies with Inverted Prelands
  14. In Situ Polymerization of PET in the Presence of Pristine and Organo-modified Clays
  15. Rapid Communications
  16. Accurate Bio-scaling Processing of Micro Structured Shark Skin Based on Swelling of Polydimethylsiloxane
  17. PPS News
  18. PPS News
  19. Seikei Kakou Abstracts
  20. Seikei Kakou Abstracts
https://doi.org/10.3139/217.2744

Articles in the same Issue

  1. Contents
  2. Contents
  3. Regular Contributed Articles
  4. Climatic Ageing of Components of Polymer Based Electrochromic Devices
  5. Previous Experimental Polymer Rheology Versus Flow Induced Crystallization
  6. Studies on the Effect of Pellet Size on Positive Conveying in Helically Grooved Single Screw Extruders
  7. Distortion of Interfaces in a Multilayer Polymer Co-extrusion Feedblock
  8. Preparation and Characterization of PES and PA Composite Membranes for Air Separation at Low Pressures
  9. Impact of Feed Opening Width and Position on PVC Extrusion Process Effectiveness
  10. Irradiation Strategy for Laser Transmission Welding of Thermoplastics Using High Brilliance Laser Source
  11. Polytetrafluoroethylene Paste Extrusion: A Fibrillation Model and Its Relation to Mechanical Properties
  12. Improving Weld Line Strength of Fiber Reinforced Plastics By Means of A “Flow Disruptor”
  13. Application of the Network Simulation Method to Flat Dies with Inverted Prelands
  14. In Situ Polymerization of PET in the Presence of Pristine and Organo-modified Clays
  15. Rapid Communications
  16. Accurate Bio-scaling Processing of Micro Structured Shark Skin Based on Swelling of Polydimethylsiloxane
  17. PPS News
  18. PPS News
  19. Seikei Kakou Abstracts
  20. Seikei Kakou Abstracts
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