Dissolvable Chipless RFID Targets Smarter Plastic Recycling
Kevin Sun’s ISEF 2026 research combines printable chipless RFID with conductive MXene to identify plastics before recycling. The tag survives product use, then disappears during alkaline washing to avoid contaminating recycled material.
Chipless RFID for Plastic Waste Sorting
Plastic recycling depends on separating polymer types correctly. Resin codes and optical methods such as visible, near-infrared and FTIR analysis can struggle with dark or filled plastics, multilayer materials, contamination and unfavorable orientation.
At Regeneron ISEF 2026, Kevin Sun, a student at Andover High School in Massachusetts, USA, presented MATS054 – MXene-Based RFID Tags for Plastic Waste Sorting. The project received the $10,000 Craig R. Barrett Award for Innovation.
A Wireless Barcode Printed Into Plastic
Instead of an integrated RFID chip, the concept uses conductive resonators. Each geometry creates a characteristic response across several radio frequencies, forming what Sun describes as a wireless barcode.
MXene ink can be printed onto plastic sheets before they are molded into products. At the sorting line, the material can then be distinguished by the tag’s unique frequency signature.
Unlike optical systems, the RF approach does not require the same direct line of sight and can work despite orientation or surface debris. Sun designed the resonators with simulation software and printed the MXene ink using a modified 3D-printer setup.
PVA Stabilizes the Signal
MXene is highly conductive but oxidizes in air, reducing conductivity and changing the RF response. Sun therefore coated part of the tags with an ultrathin polyvinyl alcohol, or PVA, oxygen barrier.
During six weeks of testing, coated tags maintained a stable response, with distinct resonant notches visible across multiple frequencies.
Designed to Disappear During Recycling
In simulated industrial caustic washes, traces from coated and uncoated tags were fully removed within about five minutes. Sun notes that such washes typically last around 20 minutes.
This addresses a key issue for smart packaging: the identifier itself should not become a persistent contaminant. The MXene structure and PVA coating are designed to be removed during an existing recycling step.
RFID Without a Semiconductor
The concept differs from conventional RAIN UHF RFID. RAIN RFID uses a semiconductor IC connected to an antenna and a standardized air interface. Sun’s chipless approach contains no silicon chip and stores no EPC or conventional digital memory.
Identification comes from the resonator geometry and frequency response. This could reduce electronic material where only a simple identifier is required.
The project remains research rather than a commercial RFID solution. Industrial deployment would still require validation at sorting-line speeds, scalable manufacturing, suitable reader infrastructure and testing across different plastics and geometries.
The principle is clear: embed identification when the product is made, identify it wirelessly when it becomes waste, and make the identifier disappear before the material starts its next lifecycle.
Because MXene conductivity changes through oxidation, Sun also sees potential for sensing applications such as freshness monitoring.
Read more at: ISEF 2026 Project MATS054: MXene-Based RFID Tags for Plastic Waste Sorting
Postlude: A New Design Brief for Packaging Technology
For technology companies serving packaging and recycling, Sun’s project points to a broader challenge: identification should be designed for the entire material lifecycle. Future smart packaging may need to combine reliable identification during production, logistics and use with easy separation or removal at end of life.
Chipless RFID, printable electronics, new conductive materials and sensing functions could therefore become increasingly relevant wherever packaging intelligence and recyclability need to work together.