Temperature window effect and its application in extrusion of ultrahigh molecular weight polyethylene
Ultrahigh molecular weight polyethylene (UHMWPE) was ram extruded using a temperature window effect. The extrusion pressure abruptly drops at a very narrow extrusion temperature window which is about 10°C higher than the theoretical melting point of orthorhombic polyethylene crystals under quiescent...
Format: | Article |
---|---|
Language: | English |
Published: |
Budapest University of Technology
2011-08-01
|
Series: | eXPRESS Polymer Letters |
Subjects: | |
Online Access: | http://www.expresspolymlett.com/letolt.php?file=EPL-0002292&mi=cd |
id |
doaj-b64835bda8d14cdf8fd3666c57f9e186 |
---|---|
record_format |
Article |
spelling |
doaj-b64835bda8d14cdf8fd3666c57f9e1862020-11-24T22:49:02ZengBudapest University of Technology eXPRESS Polymer Letters1788-618X2011-08-015867468410.3144/expresspolymlett.2011.66Temperature window effect and its application in extrusion of ultrahigh molecular weight polyethyleneUltrahigh molecular weight polyethylene (UHMWPE) was ram extruded using a temperature window effect. The extrusion pressure abruptly drops at a very narrow extrusion temperature window which is about 10°C higher than the theoretical melting point of orthorhombic polyethylene crystals under quiescent and equilibrium states. The correlation between extrusion pressure and parameters such as extrusion temperature, annealing condition, thermal history, piston velocity, L/D ratio of the die, and molecular weight of UHMWPE, was studied. The temperature window increases with molecular weight and is unaffected by thermal history and annealing. The stable extrusion pressure and the critical piston velocity decrease with the rise in the extrusion temperature. The flow resistance reversely depends on the L/D ratio of the die. This phenomenon is attributed to an extensional flow-induced chain alignment along the streamline, which results in the formation of a metastable mesophase with higher chain mobility.http://www.expresspolymlett.com/letolt.php?file=EPL-0002292&mi=cdBiocompatible polymersProcessing technologiesTemperature windowUHMWPE |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
title |
Temperature window effect and its application in extrusion of ultrahigh molecular weight polyethylene |
spellingShingle |
Temperature window effect and its application in extrusion of ultrahigh molecular weight polyethylene eXPRESS Polymer Letters Biocompatible polymers Processing technologies Temperature window UHMWPE |
title_short |
Temperature window effect and its application in extrusion of ultrahigh molecular weight polyethylene |
title_full |
Temperature window effect and its application in extrusion of ultrahigh molecular weight polyethylene |
title_fullStr |
Temperature window effect and its application in extrusion of ultrahigh molecular weight polyethylene |
title_full_unstemmed |
Temperature window effect and its application in extrusion of ultrahigh molecular weight polyethylene |
title_sort |
temperature window effect and its application in extrusion of ultrahigh molecular weight polyethylene |
publisher |
Budapest University of Technology |
series |
eXPRESS Polymer Letters |
issn |
1788-618X |
publishDate |
2011-08-01 |
description |
Ultrahigh molecular weight polyethylene (UHMWPE) was ram extruded using a temperature window effect. The extrusion pressure abruptly drops at a very narrow extrusion temperature window which is about 10°C higher than the theoretical melting point of orthorhombic polyethylene crystals under quiescent and equilibrium states. The correlation between extrusion pressure and parameters such as extrusion temperature, annealing condition, thermal history, piston velocity, L/D ratio of the die, and molecular weight of UHMWPE, was studied. The temperature window increases with molecular weight and is unaffected by thermal history and annealing. The stable extrusion pressure and the critical piston velocity decrease with the rise in the extrusion temperature. The flow resistance reversely depends on the L/D ratio of the die. This phenomenon is attributed to an extensional flow-induced chain alignment along the streamline, which results in the formation of a metastable mesophase with higher chain mobility. |
topic |
Biocompatible polymers Processing technologies Temperature window UHMWPE |
url |
http://www.expresspolymlett.com/letolt.php?file=EPL-0002292&mi=cd |
_version_ |
1725677483129307136 |