Development Trends in Bio-Based Barrier Materials
Barrier Materials Are Undergoing a Fundamental Restructuring of Material Systems
Food, pharmaceutical, and personal care packaging requires barriers against oxygen, water vapor, oils and greases, aromas, and other small molecules. Traditional high-barrier packaging often relies on multilayer petroleum-based polymers, aluminum foil, or complex multilayer structures. While these solutions offer well-established performance, growing requirements for recyclability and lower carbon footprints are driving material design toward paper-based substrates, bio-based polymers, and renewable functional barrier layers.
A wide range of materials—including cellulose, nanocellulose, starch, chitosan, proteins, PLA, and PHA—are being explored for the development of bio-based barrier systems. The emerging trend is not to rely on a single material to address all performance requirements, but rather to assign different functions to different layers within a multilayer structure, enabling each material to perform the role for which it is best suited.
The Advantage of Nanocellulose Lies in Its Ability to Create Dense, Tortuous Diffusion Pathways
Once nanocellulose forms a continuous film, its nanoscale network can significantly increase the diffusion path length for oxygen and other small molecules, giving it excellent potential for oxygen barrier performance under dry conditions. Nanocellulose also exhibits good compatibility with paper-based materials and can be applied as a thin coating or interlayer, enabling functional performance with relatively low material usage.
However, its hydrophilicity remains a key limitation. As humidity increases, water molecules penetrate the cellulose network and weaken the hydrogen-bonding interactions, resulting in reduced oxygen barrier performance and dimensional stability. Therefore, the development of bio-based high-barrier materials is increasingly focused on the synergistic design of a “hydrophilic, high-oxygen-barrier layer + hydrophobic water-vapor barrier layer.”
Multilayer Structures, Surface Engineering, and Active Functionality Are Emerging as Key Development Directions
Research reviews published in 2025 have focused extensively on surface hydrophobization strategies, including the use of fatty acids, silanes, and cold plasma treatments, as well as functional components such as lignin, tannins, and nanoclays. Another major approach is to employ multilayer structures, thereby avoiding the need for a single material to simultaneously provide mechanical strength, water-vapor resistance, oxygen barrier performance, and heat-sealing functionality.
At the same time, the boundary between barrier materials and active packaging is becoming increasingly blurred. Functions such as antioxidant activity, antimicrobial protection, adsorption, and intelligent indication can be integrated into barrier layers, enabling packaging to evolve beyond simply “delaying the permeation of substances” toward “actively regulating the internal packaging environment.”
Sustainability Assessment Will Influence Material Selection
A renewable material source does not automatically mean that the overall material system is more environmentally sustainable. Future assessments will place greater emphasis on factors such as energy consumption during raw material preparation, chemical usage, coating weight, drying energy requirements, packaging lightweighting, recyclability, composting conditions, and life cycle assessment (LCA).
Therefore, industrial-scale applications are more likely to prioritize “thin, highly efficient functional layers” rather than thick, fully bio-based structures. For paper-based packaging, enhancing barrier performance through thin nanocellulose coatings and other bio-based functional materials, while maintaining compatibility with existing paper recycling systems, represents a practical and promising development pathway.
Material Directions of Interest to CelluBio
CNF is well suited for forming continuous fibrillar networks and dense barrier layers. CNC can be utilized for nanoscale reinforcement, interfacial regulation, and functional composites. Hydrophobically modified materials such as H-CNF/H-CNC can be explored to improve moisture resistance and compatibility with nonpolar interfaces. Lignin-containing nanocellulose can further enable the investigation of UV absorption, antioxidant activity, and interfacial functionality.
In practical material design, these components should be strategically combined according to the target permeant, environmental humidity, substrate characteristics, and processing method to achieve an optimized barrier system.
Sources and Further Reading
• Goetten de Lima, G. et al. Enhancing Barrier and Antioxidant Properties of Nanocellulose Films for Coatings and Active Packaging: A Review. ACS Applied Nano Materials, 2025.
• A review on surface and interface engineering of nanocellulose and its application in smart packaging. Advances in Colloid and Interface Science, 2025, 345:103645.
• Reddy, T.R.K. et al. A review on nanocellulose in food packaging. International Journal of Biological Macromolecules, 2025.
Note: This article is intended for technical exchange and discussion within the industry and is based on publicly available research and technological developments. The specific properties and performance of the materials may vary depending on raw materials, surface chemistry, dispersion state, formulation, and processing conditions. Actual applications should be validated through laboratory-scale testing. For applications involving food, medical, or other regulated fields, applicable regulations and compliance requirements for the end products must also be satisfied.