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Light-activated adhesives bond in seconds and can be recycled in your microwave

A team led by Prof. Shlomo Magdassi from the Institute of Chemistry and Prof. Hanna Dodiuk from Shenkar College has recently developed a new adhesive that addresses one of the major challenges in materials science: developing adhesives that, on the one hand, have rapid curing capabilities and can function on a wide range of surfaces, and, on the other hand, are recyclable and removable without compromising their properties.

The research was performed by Ph.D. student Natanel Jarach and presents a new adhesive that can be cured across almost the entire visible light spectrum and can be decomposed using a household microwave, all without requiring solvents, UV radiation, or high temperatures. The adhesive bonds and debonds on demand and can be reused multiple times without losing its properties. The study is in the journal Advanced Materials.

The adhesive paradox: Strength vs. sustainability

More than 90% of the $92.6 billion global adhesives market relies on thermosets: polymers and plastics, like epoxy and silicones, which form irreversible bonds and accumulate in landfills. Even recyclable alternatives, like reversible adhesives based on dynamic covalent chemistry, often demand energy-intensive processes like prolonged heating above 150°C, toxic solvents, or deep UV, or they enable recycling only by compromising performance.

The answer? A dynamic polymer derived from α-lipoic acid (ALA), a naturally occurring antioxidant, that redefines material lifecycles.

Dual-activation design: Bond like Velcro, recycle like LEGO

TetraALA's secret lies in its four-armed molecular structure, synthesized via a one-pot reaction between alpha lipoic acid and pentaerythritol. The new adhesive photocures in 30 seconds under visible wavelengths (400–650 nm) and maintains strong adhesion to glass, plastic, aluminum, and circuit board materials (4–6 MPa), and it even functions underwater. The bonding is enabled by dynamic disulfide linkages that lock into place on curing and can be undone with mild microwave radiation: no solvents, no high temperatures.

"You can bond glass to metal or plastic in seconds, and when you're done, debond it with a kitchen microwave," said the authors. They demonstrated that more than 90% of the material could be recovered after just 30 seconds of microwave exposure. Better still, the adhesive retains its mechanical, thermal, and optical properties after multiple cycles of bonding and debonding.

The adhesive's optical clarity and high refractive index (1.62) are also suitable for optical applications such as beam splitters. The team even showed that using tap water can enhance bonding strength due to ion exchange effects. Furthermore, they have also demonstrated that this new adhesive has some biomedical potential, achieving 145 kPa shear strength on chicken skin using 630 nm light, matching surgical glues but with reversible bonding.

The study opens new possibilities for reusable consumer electronics, sustainable packaging, optical devices, and even bio-adhesives for wet tissues. The authors plan to explore industrial-scale recycling strategies and the underlying microwave-induced bond dissociation mechanisms in future work.