Related Experiment Video
Updated: Jul 14, 2026
09:22
Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Solvation and aggregation of polyphenylethynylene based anionic polyelectrolytes in dilute solutions.
Palwinder Kaur1, Hongjun Yue, Mingyan Wu
1Chemistry Department, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
The Journal of Physical Chemistry. B
|June 15, 2007
Summary
The aggregation of a conjugated polyelectrolyte (PP2) significantly alters its fluorescence. Adding counterions or surfactants can control this aggregation, reversibly tuning the polymer
Area of Science:
- Polymer Science
- Photophysics
- Materials Chemistry
Background:
- Conjugated polyelectrolytes exhibit unique optical properties.
- Solution conditions can influence polymer aggregation and spectral behavior.
Purpose of the Study:
- Investigate the impact of solution conditions on polyphenylethynylene based conjugated polyelectrolyte (PP2) properties.
- Understand the aggregation behavior of PP2 and its effect on fluorescence.
Main Methods:
- Absorption and fluorescence spectroscopy.
- Varying solution conditions (counterions, surfactants, concentration, temperature, solvent).
Main Results:
- PP2 fluorescence is quenched by counterions (Na+, K+, Li+, TBA+) due to salt-stabilized aggregate formation.
- Aggregate formation is confirmed by concentration, temperature, and solvent studies.
- Cationic surfactants disrupt PP2 aggregates, forming new polymer/surfactant aggregates with unaggregated spectral properties.
Conclusions:
- The aggregation state of PP2 is highly sensitive to solution conditions.
- Controlling aggregation through counterions and surfactants allows for tuning of spectral properties.
- PP2 shows potential for applications requiring responsive fluorescent materials.
Related Concept Videos
02:42Aqueous Solutions and Heats of Hydration
Water and other polar molecules are attracted to ions. The electrostatic attraction between an ion and a molecule with a dipole is called an ion-dipole attraction. These attractions play an important role in the dissolution of ionic compounds in water.
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
03:00Solubility
Solution, Solubility, and Solubility Equilibrium
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules, atoms, and/or ions)...
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules, atoms, and/or ions)...
01:20Anionic Chain-Growth Polymerization: Overview
The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...
01:29The Colloidal State
The formation of a colloidal system is exemplified by an aqueous solution containing Cl− ions is introduced to another containing Ag+ ions, resulting in the precipitation of solid AgCl as extremely tiny crystals. Instead of settling out as a filterable precipitate, these crystals remain suspended in the liquid, showcasing a colloidal system.A colloidal system involves colloidal particles within the approximate range of 1 to 1000 nm in at least one dimension, dispersed in a medium called the...
04:01Factors Affecting Solubility
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Chȃtelier’s principle. Consider the dissolution of silver iodide:
01:17Ion Exchange
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or basic...