Advanced

Development of a Novel Method for Evaluation of Interfacial Tension between Polymer Melts

Rundqvist, Thomas LU (1997)
Abstract
A novel method for the evaluation of interfacial tension of high viscosity polymer melts is described. The method involves the tracking of the shape evolution of a highly deformed droplet of one material imbedded in a second one. This makes it possible to determine the interfacial tension over a relatively short time period. The imbedded material is initially either a fiber or a disk. The technique of preparing the samples makes it possible to measure on practically any combination of polymer melts without restrictions on viscosities and melting temperature, as long as one of the materials is transparent in the molten state.



The retraction of the disk is observed by using a microscope with a high resolution video camera... (More)
A novel method for the evaluation of interfacial tension of high viscosity polymer melts is described. The method involves the tracking of the shape evolution of a highly deformed droplet of one material imbedded in a second one. This makes it possible to determine the interfacial tension over a relatively short time period. The imbedded material is initially either a fiber or a disk. The technique of preparing the samples makes it possible to measure on practically any combination of polymer melts without restrictions on viscosities and melting temperature, as long as one of the materials is transparent in the molten state.



The retraction of the disk is observed by using a microscope with a high resolution video camera connected to a personal computer. Data of the retraction is acquired by using an image analysis software, measuring the dimensions of the imbedded material.



The driving force for the shape evolution is interfacial tension and it is balanced by viscous forces. The analysis of the retraction process is done analytically with a simplified one dimensional model. The model is compared to experiments with the polymers PS/PMMA at 210°C, covering viscosity ratios over a range of six decades. It is shown that interfacial tension can be determined over the whole range and a value of 1.1 ± 0.3 mN/m was obtained for all samples.



PS/PMMA is also studied in the temperature range 150-250°C where the interfacial tension is found to be 3.6 - 0.012 (T - 273) mN/m, where T is the temperature in K. Viscosities were in the range from 10^2 to 10^6 Pa s.



Further, the interfacial tension is measured between PP/PA, PP/PBT, and PP/LCP. For these blends the effect of reactive compatibilizers on the interfacial tension is evaluated. The interfacial tension is found to decrease with the addition of the compatibilizer. The measured interfacial correlates well with the morphology of the blends. (Less)
Please use this url to cite or link to this publication:
author
opponent
  • Professor Hrymak, Andrew N., McMaster University, Hamilton, Canada
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Polymer technology, Polymer Blends, Imbedded Fiber, Imbedded Disk, High viscosity, Interfacial tension, Polymer melts, biopolymers, Polymerteknik
pages
116 pages
publisher
Department of Production and Materials Engineering, LTH, Lund University,
defense location
Room M:B, Lund Institute of Technology, Lund University
defense date
1997-05-07 10:15
external identifiers
  • Other:ISRN: LUTMDN/(TMMV-1031)/1-55/(1997)
language
English
LU publication?
yes
id
348bddd3-ba1b-48d3-8ed4-47baf34c1d67 (old id 29236)
date added to LUP
2007-06-14 15:44:24
date last changed
2016-09-19 08:45:13
@misc{348bddd3-ba1b-48d3-8ed4-47baf34c1d67,
  abstract     = {A novel method for the evaluation of interfacial tension of high viscosity polymer melts is described. The method involves the tracking of the shape evolution of a highly deformed droplet of one material imbedded in a second one. This makes it possible to determine the interfacial tension over a relatively short time period. The imbedded material is initially either a fiber or a disk. The technique of preparing the samples makes it possible to measure on practically any combination of polymer melts without restrictions on viscosities and melting temperature, as long as one of the materials is transparent in the molten state.<br/><br>
<br/><br>
The retraction of the disk is observed by using a microscope with a high resolution video camera connected to a personal computer. Data of the retraction is acquired by using an image analysis software, measuring the dimensions of the imbedded material.<br/><br>
<br/><br>
The driving force for the shape evolution is interfacial tension and it is balanced by viscous forces. The analysis of the retraction process is done analytically with a simplified one dimensional model. The model is compared to experiments with the polymers PS/PMMA at 210°C, covering viscosity ratios over a range of six decades. It is shown that interfacial tension can be determined over the whole range and a value of 1.1 ± 0.3 mN/m was obtained for all samples.<br/><br>
<br/><br>
PS/PMMA is also studied in the temperature range 150-250°C where the interfacial tension is found to be 3.6 - 0.012 (T - 273) mN/m, where T is the temperature in K. Viscosities were in the range from 10^2 to 10^6 Pa s.<br/><br>
<br/><br>
Further, the interfacial tension is measured between PP/PA, PP/PBT, and PP/LCP. For these blends the effect of reactive compatibilizers on the interfacial tension is evaluated. The interfacial tension is found to decrease with the addition of the compatibilizer. The measured interfacial correlates well with the morphology of the blends.},
  author       = {Rundqvist, Thomas},
  keyword      = {Polymer technology,Polymer Blends,Imbedded Fiber,Imbedded Disk,High viscosity,Interfacial tension,Polymer melts,biopolymers,Polymerteknik},
  language     = {eng},
  pages        = {116},
  publisher    = {ARRAY(0x889eca8)},
  title        = {Development of a Novel Method for Evaluation of Interfacial Tension between Polymer Melts},
  year         = {1997},
}