Diffusion properties of inkjet printed ionic self-assembling polyelectrolyte hydrogels

Area of Science:

• Materials Science
• Polymer Chemistry
• Chemical Engineering

Background:

• Inkjet printing enables precise fabrication of polyelectrolyte complexes.
• Understanding solute transport is crucial for applications of these materials.

Purpose of the Study:

• To characterize solute transport in inkjet-printed polyelectrolyte gels.
• To investigate the influence of stoichiometry on gel structure and transport properties.

Main Methods:

• Utilized Crank's model to analyze solute diffusion.
• Investigated diffusion of fluorescein, dextrans, and albumin.
• Analyzed polyelectrolyte complex structures at varying stoichiometric ratios.

Main Results:

• Diffusion coefficients varied significantly with molecule size and charge (10^-8 to 10^-10 cm²/sec).
• Non-stoichiometric ratios yielded non-equilibrium structures with distinct polymer chain populations.
• Potential for multiple phases in non-stoichiometric complexes was identified.

Conclusions:

• Crank's model effectively characterizes solute transport in these gels.
• Stoichiometry critically influences the structure and transport dynamics of printed polyelectrolyte complexes.
• Hydrodynamic and free volume models may be applicable for describing transport phenomena.