Enhancing barrier and mechanical properties of paper through NMMO/cellulose solution coating

The inherent limitations in barrier and mechanical properties of untreated paper-based materials restrict their potential for broader application. This study proposes a method for fabricating composite paper by applying an ultra-thin layer of regenerated cellulose film onto paper substrates using a Mayer bar coating technique. The incorporation of regenerated cellulose film markedly enhances the barrier properties, hydrophobicity, and mechanical properties of the resulting composites. Compared to the unmodified control paper, the composite paper exhibits a significant decrease in air, water vapor, and oxygen permeability by 99.3%, 82.4%, and 99.3%, respectively. Improved water resistance and hydrophobicity are indicated by increased water contact angle, reduced Cobb value, and prolonged water droplet retention time. Furthermore, the composite paper demonstrates enhanced dry tensile index, wet tensile index, bursting index, and internal bond strength by 8.9, 4.5, 5.1, and 0.35 times, respectively, compared to the control paper. This study provides a simple and effective strategy for fabricating composite paper with outstanding barrier and mechanical properties, showcasing significant potential for functional packaging applications.