The Institute for Bioengineering of Catalonia introduced a biomaterial that is not only waterproof but also becomes more durable when it comes in contact with water. The particular research was reported in Nature Communications on 18 February 2026.
The End of Soggy Bioplastics: Scientists Created a Plastic-Alternative Biomaterial Made of Chitosan and Doped With Nickel that Becomes Stronger With Moisture
Background
A team of scientists and engineers was working on developing a sustainable material based on the principles of a circular economy. Their specific goal was to create a plastic substitute that uses waste products, requires low energy to produce, and is environmentally benign. Their attention was directed toward chitosan.
Chitosan is a polymer obtained from chitin. Moreover, chitin is the second most abundant organic polymer on the planet. It provides structural integrity to the exoskeletons of crustaceans, cell walls of fungi, and other invertebrates. The most common source of chitin is the shells of crustaceans discarded by the seafood industry.
Javier Fernández, a prominent figure in the field of sustainable materials and bioengineering, led the research team. They focused on a process called vitrification and the use of metal-coordination chemistry to dope chitosan with small amounts of nickel ions and transform it into a high-performance biomaterial.
Main Findings
Water typically acts as a plasticizer for biopolymers like paper and starch. This means it gets between the molecular chains and pushes them apart to make the material soft and weak. This is the reason why most commercial bioplastic materials are produced with chemical modifications or protective coatings.
The incorporation of nickel ions in chitosan creates a material that thrives in humid environments. While traditional bioplastics fail when exposed to moisture, this innovation leverages hydration to reinforce its internal architecture. The following points detail the specific data and mechanical observations recorded:
• Wet Strength Paradox: The material becomes two times stronger when it is wet compared to its dry state. This contradicts the behavior of almost all other natural fibers, which typically soften and lose their shape when exposed to significant amounts of environmental water or high humidity.
• Plastic Benchmark Performance: Testing showed that the tensile strength of this material surpasses that of common polyethylene and polypropylene. These prove that bio-based alternatives can finally match or exceed the durability of plastics that currently dominate the global manufacturing and packaging industries.
• Dynamic Molecular Bonding: Water molecules act as bridges between the nickel ions and the chitosan chains to lock the structure. This creates a responsive network that can reconfigure under stress. This molecular flexibility prevents the brittle fractures often seen in other rigid bio-plastic materials.
Takeaways
The methodology demonstrates that high-performance materials do not require unsustainable and toxic industrial processes. Remember that chitosan is a massive byproduct of the seafood industry. Moreover, this natural polymer was vitrified with small traces of nickel at room temperature to turn it into a thin and solid film.
It is also worth noting that the discovery marks a fundamental shift in how engineers approach the problem of water sensitivity in bio-based products. Specifically, instead of waterproof coatings or the addition of other chemicals, the process shows that manufacturers can design materials that use moisture to remain durable.
Future applications include high-performance packaging and consumer goods that must withstand outdoor conditions or refrigeration. The chitosan-nickel material is a promising alternative to plastics. It has around 35.0 MPa tensile strength when dry and about 70.0 MPa when wet. Plastics have between 10.00 and 40.0 MPa.
Further Readings and References
- Kompa, A. and G. Fernandez, J. 2026. “Stronger When Wet: Aquatically Robust Chitinous Objects Via Zero-waste Coordination With Metal Ions.” Nature Communications. 17(1). DOI: 1038/s41467-026-69037-4