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Study on Structure and Vacuum Membra...

Chen, Zuolong.

Study on Structure and Vacuum Membrane Distillation Performance of PVDF Composite Membranes: Influence of Molecular Weight and Blending.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Study on Structure and Vacuum Membrane Distillation Performance of PVDF Composite Membranes: Influence of Molecular Weight and Blending.
Author:	Chen, Zuolong.
Description:	129 p.
Notes:	Source: Masters Abstracts International, Volume: 52-06.
Contained By:	Masters Abstracts International52-06(E).
Subject:	Chemical engineering.
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=MS26632
ISBN:	9780499266323

Study on Structure and Vacuum Membrane Distillation Performance of PVDF Composite Membranes: Influence of Molecular Weight and Blending.
Chen, Zuolong.

Study on Structure and Vacuum Membrane Distillation Performance of PVDF Composite Membranes: Influence of Molecular Weight and Blending. - 129 p.

Source: Masters Abstracts International, Volume: 52-06.

Thesis (M.A.Sc.)--University of Ottawa (Canada), 2014.

This item must not be sold to any third party vendors.

In this study, membranes were made from three polyvinylidene fluoride (PVDF) polymers individually and the blend systems of high (H) and low (L) molecular weight PVDF by phase inversion process. After investigating membrane casting solutions' viscous and thermodynamic properties, the membranes so fabricated were characterized by scanning electron microscopy, gas permeation tests, porosity measurement, contact angle (CA) and liquid entry pressure of water (LEPw) measurement, and further subjected to vacuum membrane distillation (VMD) in a scenario that was applicable for cooling processes, where the feed water temperature was maintained at 27°C. It was found that PVDF solutions' viscosities and thermodynamic instabilities were determined by the types of PVDF employed in single polymer systems and the mixing ratios of two PVDF polymers in blend systems. Thus the membrane properties and performances were influenced by the aforesaid factors as well. In single polymer systems, it was found that the membrane surface roughness and porosity increased with an increase in molecular weight. Among all the membranes casted in this study, the water vapor flux of VMD was found to be the highest at the intermediate range of H:L ratio, i.e., 4:6, at which the thickness of the sponge-like layer showed a minimum, the finger-like macro-voids formed a more orderly single-layer structure, and the LEPw showed a minimum. A conclusion can be made that blend systems of high molecular weight PVDF polymers and low molecular weight PVDF polymers could be used to optimize membrane performance in vacuum membrane distillation.

ISBN: 9780499266323Subjects--Topical Terms:

206267
Chemical engineering.

Study on Structure and Vacuum Membrane Distillation Performance of PVDF Composite Membranes: Influence of Molecular Weight and Blending.
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020 $a 9780499266323
035 $a (MiAaPQ)AAIMS26632
035 $a AAIMS26632
040 $a MiAaPQ $c MiAaPQ
100 1 $a Chen, Zuolong. $3 708820
245 1 0 $a Study on Structure and Vacuum Membrane Distillation Performance of PVDF Composite Membranes: Influence of Molecular Weight and Blending.
300 $a 129 p.
500 $a Source: Masters Abstracts International, Volume: 52-06.
502 $a Thesis (M.A.Sc.)--University of Ottawa (Canada), 2014.
506 $a This item must not be sold to any third party vendors.
506 $a This item must not be added to any third party search indexes.
520 $a In this study, membranes were made from three polyvinylidene fluoride (PVDF) polymers individually and the blend systems of high (H) and low (L) molecular weight PVDF by phase inversion process. After investigating membrane casting solutions' viscous and thermodynamic properties, the membranes so fabricated were characterized by scanning electron microscopy, gas permeation tests, porosity measurement, contact angle (CA) and liquid entry pressure of water (LEPw) measurement, and further subjected to vacuum membrane distillation (VMD) in a scenario that was applicable for cooling processes, where the feed water temperature was maintained at 27°C. It was found that PVDF solutions' viscosities and thermodynamic instabilities were determined by the types of PVDF employed in single polymer systems and the mixing ratios of two PVDF polymers in blend systems. Thus the membrane properties and performances were influenced by the aforesaid factors as well. In single polymer systems, it was found that the membrane surface roughness and porosity increased with an increase in molecular weight. Among all the membranes casted in this study, the water vapor flux of VMD was found to be the highest at the intermediate range of H:L ratio, i.e., 4:6, at which the thickness of the sponge-like layer showed a minimum, the finger-like macro-voids formed a more orderly single-layer structure, and the LEPw showed a minimum. A conclusion can be made that blend systems of high molecular weight PVDF polymers and low molecular weight PVDF polymers could be used to optimize membrane performance in vacuum membrane distillation.
590 $a School code: 0918.
650 4 $a Chemical engineering. $3 206267
690 $a 0542
710 2 $a University of Ottawa (Canada). $b Chemical and Biological Engineering. $3 708821
773 0 $t Masters Abstracts International $g 52-06(E).
790 $a 0918
791 $a M.A.Sc.
792 $a 2014
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=MS26632