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The influence of surface hydrophobicity on polyacrylamide adsorption
Iliana G Sedeva1, Daniel Fornasiero, John Ralston
1Ian Wark Research Institute, University of South Australia, Mawson Lakes, Adelaide, SA 5095, Australia.
Langmuir : the ACS Journal of Surfaces and Colloids
|March 5, 2009
Summary
Modified polyacrylamide adsorption on gold surfaces increases with hydrophobicity. The polymer layer
Area of Science:
- Surface Science
- Polymer Science
- Materials Science
Background:
- Understanding polymer adsorption is crucial for applications like coatings and biomaterials.
- Surface hydrophobicity significantly influences polymer-surface interactions.
- Polyacrylamide derivatives are widely used in various industrial applications.
Purpose of the Study:
- To investigate the adsorption behavior of modified polyacrylamide on gold surfaces with varying hydrophobicity.
- To elucidate the conformational changes and morphological characteristics of the adsorbed polymer layer.
- To assess the impact of polymer adsorption on surface hydrophobicity reduction.
Main Methods:
- Quartz Crystal Microbalance with Dissipation (QCM-D) to monitor adsorption kinetics and layer properties.
- Tapping-Mode Atomic Force Microscopy (TM-AFM) for imaging the morphology of the adsorbed polymer layer.
- Captive Bubble Contact Angle measurements to quantify surface hydrophobicity.
Main Results:
- Polymer adsorption rate and extent increased with substrate hydrophobicity.
- Adsorption on hydrophobic surfaces induced polymer conformational changes, forming less rigid layers.
- AFM revealed incomplete polymer coverage, with morphology dependent on substrate hydrophobicity.
Conclusions:
- Substrate hydrophobicity is a key factor governing polyacrylamide adsorption kinetics, conformation, and layer morphology.
- The modified polyacrylamide exhibits varying effectiveness in reducing surface hydrophobicity based on its coverage and distribution.
- These findings provide insights into tailoring polymer-surface interactions for specific applications.
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