Adjusting the Ion Permeability of Polyelectrolyte Multilayers through Layer-by-Layer Assembly under a High Gravity...

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Layer-by-layer (LbL) assembly is a versatile technique for creating multilayer films with tunable permeability and compactness.
• Controlling film compactness in LbL assembly remains a challenge, limiting its application potential.

Purpose of the Study:

• To introduce a simple mechanical energy source, high gravity, to control multilayer film compactness and permeability.
• To investigate the effect of high gravity on the LbL assembly process using a model system.

Main Methods:

• Utilized a high gravity field during the LbL assembly of poly(diallyldimethylammonium chloride) (PDDA) and poly{1-4[4-(3-carboxy-4-hydroxyphenylazo)benzenesulfonamido]-1,2-ethanediyl sodium salt} (PAzo).
• Varied the rotational speed of the high gravity equipment and the concentration of precursor solutions.
• Analyzed film compactness using surface morphology, cyclic voltammetry, and photoisomerization kinetics.

Main Results:

• High gravity field accelerated the multilayer deposition process by 20-fold compared to conventional dipping.
• Adsorption rate increased with higher rotational speeds and solution concentrations.
• Film compactness significantly improved with increasing rotational speed, as evidenced by morphological and functional analyses.

Conclusions:

• High gravity field is a simple and effective method to enhance LbL assembly and improve film compactness.
• This approach offers a versatile strategy for tailoring multilayer properties for advanced applications.
• Potential applications include controlled ion permeability, anticorrosion coatings, and drug loading systems.