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Extraction and Characterization of Surfactants from Atmospheric Aerosols
Published on: April 21, 2017
Aqueous behaviour of cationic surfactants containing a cleavable group
Austin Samakande1, Radhouane Chaghi, Gaelle Derrien
1UNESCO Associated Centre for Macromolecules, Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, 7602 Stellenbosch, South Africa.
Journal of Colloid and Interface Science
|February 5, 2008
Summary
Two novel cationic RAFT agents, PCDBAB and DCTBAB, were studied for their aggregation behavior in dilute solutions. Their thermodynamic parameters were analyzed and compared to conventional surfactants, revealing insights into their structural relationships.
Area of Science:
- Colloid and Surface Chemistry
- Polymer Chemistry
- Physical Chemistry
Background:
- Cationic surfactants are crucial in various industrial applications.
- Reversible Addition-Fragmentation chain Transfer (RAFT) agents are essential for controlled polymerization.
- Understanding the aggregation behavior of novel surfactant structures is key to developing advanced materials.
Purpose of the Study:
- To investigate the aggregation behavior of two novel cationic RAFT agents: N,N-dimethyl-N-(4-(((phenylcarbonothioyl)thio)methyl)benzyl)ethanammonium bromide (PCDBAB) and N-(4-((((dodecylthio)-carbonothioyl)thio)methyl)benzyl)-N,N-dimethylethanammonium bromide (DCTBAB).
- To determine and compare thermodynamic parameters such as critical micelle concentration (cmc), degree of micelle ionization (alpha), and head group surface area (a 0).
- To elucidate structural relationships by comparing these parameters with a conventional surfactant, cetyltrimethylammonium bromide (CTAB).
Main Methods:
- Surface tension measurements
- Conductimetry
- Microcalorimetry
- Thermodynamic analysis at 303 K
Main Results:
- Thermodynamic parameters including critical micelle concentration (cmc), degree of micelle ionization (alpha), head group surface area (a 0), Delta H mic, Delta G mic, and T Delta S mic were determined for PCDBAB and DCTBAB.
- Comparison with cetyltrimethylammonium bromide (CTAB) provided insights into the structural influences on aggregation.
- The hydrophobic behavior of the S-C=S- linkage and interactions involving the benzene ring were discussed.
Conclusions:
- The study successfully characterized the aggregation behavior and thermodynamic properties of novel cationic RAFT agents.
- Structural features, including the S-C=S- linkage and benzene ring, significantly influence micelle formation and properties.
- Findings contribute to the understanding of structure-property relationships in cationic surfactants and RAFT agents.
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