Professor Junjie Wu junjie.wu@durham.ac.uk
Professor
A problem in applications of ultra-high molecular weight polyethylene (UHMWPE) is the tendency for components to contain fusion defects, arising during processing of the as-polymerized powder. These defects have been implicated previously in failures of UHMWPE load-bearing surfaces, in knee and hip prostheses. Recent work of the authors has recognized two forms of defect: voids (Type 1) and particle boundaries deficient in diffusion by reptation (Type 2). To assist process and product design, a method has now been developed for predicting the decay of severity of Type 2 defects during processing, for a component of given shape and process history. A new quantifier was introduced for characterizing the progress of diffusion at Type 2 defects in UHMWPE—the maximum reptated molecular mass M. This was computed using results from reptation theory, embedded within a Finite Element thermal model of the process. The method was illustrated by simulating compression moulding trials already carried out experimentally by the same authors. It was discovered that M never reached the viscosity average molecular mass of the polymer, indicating incomplete boundary diffusion, and explaining the previous observation of Type 2 defects even in fully-compacted, apparently perfect mouldings. The method described has potential as a design tool, especially for optimizing manufacture of UHMWPE prosthesis components.
Journal Article Type | Article |
---|---|
Acceptance Date | Feb 28, 2002 |
Publication Date | 2002-07 |
Deposit Date | Jun 2, 2008 |
Journal | Chemical Engineering Research and Design |
Print ISSN | 0263-8762 |
Electronic ISSN | 1744-3563 |
Publisher | Elsevier |
Peer Reviewed | Peer Reviewed |
Volume | 80 |
Issue | A5 |
Pages | 423-431 |
DOI | https://doi.org/10.1205/026387602320224003 |
Keywords | UHMWPE, Polyethylene, Reptation, Finite element analysis, Thermal model, Fusion defects, Compression moulding, Powder processing. |
Public URL | https://durham-repository.worktribe.com/output/1558830 |
Publisher URL | http://www.extenza-eps.com/ICE/doi/abs/10.1205/026387602320224003 |
Biotribological and Structural Analyses of Large Diameter Ceramic on Carbon Fibre Reinforced PEEK Hip Joints with Different Inclination
(2011)
Presentation / Conference Contribution
A mathematical model of the eye lens epithelium of mammals that predicts cell density profiles in the ageing lens.
(2015)
Presentation / Conference Contribution
Prosim Simulator Wear Study of 60mm Diameter Zirconia Toughened Alumina Composite Hip Bearings: The Effect of High Cup Inclination Angle and Microseparation
(2011)
Presentation / Conference Contribution
Effect of Knee, Ankle and Hip Joint Replacements on Vitamin E Infused Highly Crosslinked UHMWPE Wear Particles Size, Shape and Morphologies Using a New Modified Base Digestion Method
(2015)
Presentation / Conference Contribution
Do structural alterations mediated by enzymatic activities influence the mechanical properties of capsular biomembranes?
(2014)
Presentation / Conference Contribution
About Durham Research Online (DRO)
Administrator e-mail: dro.admin@durham.ac.uk
This application uses the following open-source libraries:
Apache License Version 2.0 (http://www.apache.org/licenses/)
Apache License Version 2.0 (http://www.apache.org/licenses/)
SIL OFL 1.1 (http://scripts.sil.org/OFL)
MIT License (http://opensource.org/licenses/mit-license.html)
CC BY 3.0 ( http://creativecommons.org/licenses/by/3.0/)
Powered by Worktribe © 2024
Advanced Search