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Assembly and Characterization of Polyelectrolyte Complex Micelles
Published on: March 2, 2020
Partial molar volume of anionic polyelectrolytes in aqueous solution.
Constain Salamanca1, Martín Contreras, Consuelo Gamboa
1Facultad de Ciencias, Universidad de Chile, Santiago, Chile.
Journal of Colloid and Interface Science
|March 14, 2007
Summary
This study measured partial molar volumes of anionic polyelectrolytes and hydrophobically modified polymers. Results reveal how carboxylic groups and chain structure influence volume, with hydrophobic effects decreasing per methylene group.
Area of Science:
- Polymer Science
- Physical Chemistry
Background:
- Understanding polyelectrolyte behavior is crucial in various applications.
- Hydrophobically modified polymers exhibit unique solution properties.
Purpose of the Study:
- To measure partial molar volumes (V) of anionic polyelectrolytes and hydrophobically modified polymers (PHM).
- To investigate the influence of carboxylic groups and comonomeric structure on molar volume.
- To analyze the relationship between molar volume and hydrophobic chain length in PHM.
Main Methods:
- Density measurements in highly dilute aqueous solutions.
- Calculation of partial molar volumes (V) for various polymers.
- Analysis of structure-property relationships.
Main Results:
- Partial molar volumes varied among different polyelectrolytes, with polyacrylic acid (PAA) showing the smallest V and polymaleic acid-co-vinyl-2-pyrrolidone (AMVP) the largest.
- A linear correlation was observed between the molar volume of PHM and the number of methylene groups in their lateral chains.
- The contribution per methylene group to molar volume decreased with increasing hydrophobicity of the polymer environment.
Conclusions:
- Carboxylic groups and comonomeric structure significantly impact the partial molar volumes of anionic polyelectrolytes.
- The hydrophobic character of the polymer significantly influences the contribution of methylene groups to molar volume.
- These findings provide insights into the solution behavior of polyelectrolytes and hydrophobically modified polymers.
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