Electrostatically Complexed Natural Polysaccharides as Aqueous Barrier Coatings for Sustainable and Recyclable...

Area of Science:

• Materials Science
• Sustainable Chemistry
• Polymer Science

Background:

• Growing demand for sustainable and circular economy solutions in packaging.
• Fiber-based materials offer renewable alternatives but lack barrier properties.
• Need for functional coatings to overcome limitations of fiber-based packaging for primary applications.

Purpose of the Study:

• To develop novel waterborne complex dispersion barrier coatings from natural polysaccharides.
• To create a scalable, one-pot mechanochemical pathway for coating formulation.
• To enhance the barrier properties and recyclability of fiber-based packaging.

Main Methods:

• Utilized chitosan and carboxymethyl cellulose as natural, biodegradable polysaccharides.
• Employed a one-pot mechanochemical pathway for scalable synthesis.
• Tailored electrostatic complexation to form a highly crosslinked polymer network.
• Applied coatings to paperboard and molded pulp substrates.

Main Results:

• Achieved excellent film-forming properties and adaptable viscosity profiles.
• Formulated uniform, defect-free coating layers with enhanced barrier performance.
• Demonstrated remarkable oil and grease barrier properties.
• Significantly reduced water/moisture sensitivity while maintaining substrate recyclability.

Conclusions:

• Developed a sustainable, biorenewable, and repulpable barrier coating.
• The coating is a promising alternative for food and food service packaging.
• Addresses the limitations of fiber-based materials for primary packaging applications.