Scientists Find New Method To Recycle Fishing Nets Into 3D-Printed Products
Fishing nets are typically made of a polymer called PA-66 (Polyamide 66), an engineering plastic which is notoriously difficult to reprocess or recycle.
By Anubha Jain
Published : November 3, 2025 at 2:40 PM IST
Bengaluru: Scientists from the Indian Institute of Science (IISc), Bengaluru, have discovered a quick and practical way to recycle one of the toughest plastics—made up of a polymer called PA-66 (known as Polyamide 66 or Nylon 66)—commonly used in fishing nets and car parts.
The breakthrough, published in the Chemical Engineering Journal, explains a novel chemical process used by researchers to recycle waste from fishing nets and automotive parts. The team, led by IISc Professor Suryasarathi Bose and a PhD student S Vimal Kumar from the Department of Materials Engineering (MatE), used a chemical cross-linker called melamine to break down melted waste containing PA-66 in the presence of a catalyst.
The process rebuilds the waste plastic through a rapid reaction known as transamidation—a chemical reaction where an amide reacts with an amine to produce a new amide, essentially swapping the amine portion of the original amide. Remarkably, it takes less than two minutes and can be seamlessly integrated into existing industrial recycling systems.
“This method is designed for such industrial processes, which means that the reaction times are less than two minutes,” says S Vimal Kumar, the first author of the study. "The result is a nylon material with improved properties that remains strong and durable even after three reprocessing cycles. The recycled nylon can be used to make products that require high rigidity, like park benches, road dividers, or pavement tiles."
The startup VOiLA3D, India's first 3D printing company, co-founded by Professor Bose, has already used these recycled plastics to 3D-print a chair, furniture panels, trash bins, and even a small speedboat, along with more value-added products through extrusion-based recycling.
The 3D printing process involves melting the polymer and shaping it using a robotic extruder, which is comparatively slower than the injection moulding—a high-volume manufacturing process for making complex plastic parts by melting plastic pellets, injecting the molten material into a mould under high pressure, and then cooling and solidifying it. For instance, while injection moulding can produce around 1,000 chairs in an hour, 3D printing would take about an hour to make just one chair.
In an exclusive interview with ETV Bharat, Professor Suryasarathi Bose, the corresponding author of this innovation, discussed the technology and shared how his startup is collaborating with industry partners to develop and scale up technologies for recycling hard-to-recycle plastics, including discarded fishing nets.
Nylon-66 fishing net recycling
Explaining the inspiration behind taking up the challenge of recycling Nylon-66, Professor Bose mentioned India's long coastline, where large quantities of abandoned fishing nets are found each year. These nets are difficult to recycle and also badly affect the marine ecosystem. And hence, this motivated the team to act.
“Although Nylon-66 is an engineering plastic with many desirable properties that make it ideal for applications like fishing nets and automotive parts, it is also one of the toughest materials to recycle,” he noted. The motivation, he added, was twofold—environmental and economic.
“From an environmental perspective, we wanted to address the issue of abandoned plastic waste by converting it into a value-added product. Economically, we saw potential to create livelihood opportunities for coastal communities through this recycling process.”
Melamine-enhanced nylon recycling method
Bose explained the development of a recycling method using melamine as a cross-linker for Nylon-66, which is faster and more efficient than conventional techniques. “Melamine is inexpensive and highly multifunctional, which makes it ideal for facilitating cross-linking during recycling. Through this approach, along with a zinc-based catalyst, we were able to give Nylon-66 a new life, with the resulting material exhibiting far superior properties,” he noted.
Recycling in under two minutes: A game changer for industry
When asked about the significance of completing the recycling process in under two minutes, Professor Bose highlighted its industrial importance. “Achieving recycling in such a short time is a major advantage for large-scale operations. It makes the technology readily adaptable for industrial upscaling since most industrial processes occur in the molten state and within brief time windows. Our method, therefore, integrates seamlessly into existing manufacturing workflows,” he explained.
Overcoming scientific and technical hurdles
Discussing the scientific and technical hurdles, Bose said that the biggest issue was contamination in the recovered fishing nets, which included salt, biofoulants, and other impurities. "We partnered with Chennai-based Chimes Polymers to clean and prepare the nets for processing,” he explained.
“The second challenge was optimising the catalyst content; we ran multiple tests to identify the most effective catalyst. The third was ensuring the process could be scaled up quickly for industrial use so it could be directly adopted by manufacturing units,” he added.
Faster, cleaner, and more efficient than conventional methods
Responding to a question about what makes this method more efficient than conventional recycling techniques, Bose explained that traditional methods often require long processing hours and the use of solvents. “In contrast, our approach is energy-efficient, environmentally friendly, and much faster. Moreover, it can be extended to other polymers such as polyester and other engineering plastics, enabling the creation of materials with enhanced performance,” he said.
Ready for industrial adoption
When asked whether this recycling process could be easily adopted by industries or municipal recycling facilities, Bose emphasised that the team deliberately chose an extrusion-based upcycling method because it is one of the most practical ways to handle plastics. “Many industries already use long extruder lines to convert plastics into different shapes. Since our process is melt-based and solvent-free, it can be seamlessly integrated into existing industrial recycling systems,” he explained.
Bose emphasised the need for policy support, industry collaboration, and awareness among fishing communities to scale up the recycling method nationally or globally. He said, “To solve the problem more efficiently, we are partnering with NGOs and the fisheries department to collect abandoned fishing nets and return them to society in the form of value-added products. We can also address the problem of microplastics affecting the ecosystem by upcycling Nylon-66."
Bose explained that VOiLA3D serves as a bridge between the laboratory and the real world. “Through our partnership with VOiLA, we developed technology to recycle hard-to-recycle plastics—such as Nylon-66, polyesters, polypropylene, polyethylene, and ABS—into useful, real-world products. Collaborating with VOiLA also enabled us to carry out techno-economic and life cycle analyses for generic plastics, which was otherwise very difficult to achieve,” he said.
The startup is now extending this work to mixed nylon waste and scaling up production with partners like Chimes Polymers to recycle tons of fishing nets, thereby reducing the need for virgin plastics and preventing ocean microplastics from reaching coastal communities.
With the world producing more than 430 million tonnes of plastic every year, fishing waste is a major threat to marine life. Researchers behind the study believe that their new method offers a smart, eco-friendly way to turn discarded fishing nets into useful products—giving plastic a new life and helping clean up oceans.
