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Study of the surface character as responsible for controlling interfacial forces at membrane-feed interface
A Gugliuzza1, R Fabiano, M G Garavaglia
1Research Institute on Membrane Technology, ITM-CNR, Via Pietro Bucci 17/C, I-87030 Rende, Italy. a.gugliuzza@itm.cnr.it
Journal of Colloid and Interface Science
|September 22, 2006
Summary
Interfacial forces govern how molecules dissolve into 80PTMO/PA12 membranes. Specific chemical interactions, like H-bonding and van der Waals forces, enhance membrane affinity for penetrants, enabling selective membrane design.
Area of Science:
- Materials Science
- Polymer Chemistry
- Surface Science
Background:
- Interfacial forces play a critical role in the interaction between membrane surfaces and penetrating molecules.
- Understanding the surface characteristics of membranes is crucial for controlling dissolution processes.
Purpose of the Study:
- To evaluate the surface character of 80PTMO/PA12 membranes and its influence on the dissolution of various species (CO2, H2O, C3H6O2, C4H8O2, C5H10O2).
- To investigate the role of interfacial forces and supra-molecular chemistry in penetrant sorption within these membranes.
Main Methods:
- Infrared (IR) spectroscopy was employed to analyze membrane surface properties.
- Estimation of hydrophilic and hydrophobic domains on the membrane surface.
- Evaluation of Lewis acid/base interactions and Lifshitz-van der Waals interactions at the interface.
Main Results:
- Infrared analyses and domain estimations provided insights into the distribution and accessibility of polar moieties responsible for sorption.
- Attractive interactions, including H-bonding and specific Lifshitz-van der Waals interactions, were identified as key drivers for penetrant sorption.
- The presence of polar groups (carbonyl, sulfonamide, hydroxyl) significantly enhanced the affinity of Pebax-based membranes for the studied penetrants.
Conclusions:
- The reactivity of membrane surfaces for specific molecules can be quantified.
- This quantification enables the development of predictive models for penetrant behavior.
- The findings facilitate the rational design of highly selective membranes for various applications.
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