Electronic devices are ubiquitous in modern society, yet their poor recycling rates contribute to substantial economic losses. Here is a novel soluion.
Between upgrades and breakdowns to smartphones, tablets, laptops, and appliances, too many electronics are getting thrown into the trash and creating e-waste.
According to a 2024 report issued by the United Nations, the amount of e-waste worldwide has almost doubled in the past 12 years, from 34 billion to 62 billion kilograms — the equivalent of 1.55 million shipping trucks — and it’s estimated to hit 82 billion kilograms by 2030. Just 13.8 billion kilograms — about 20 percent of the total — is expected to be recycled, a number projected to remain flat.
In a new study in the journal Advanced Materials (“Liquid Metal-Vitrimer Conductive Composite for Recyclable and Resilient Electronics“) by two Virginia Tech research teams offers a potential solution to the e-waste problem: a recyclable material that could make electronics easier to break down and reuse.
Chemistry and engineering have an answer
Michael Bartlett, associate professor of mechanical engineering, and Josh Worch, assistant professor of chemistry have created a new class of circuit materials.
Low-melting-point metal alloys, commonly referred to as liquid metals offer the prospect of creating high-performance composites for reconfigurable electronics.
These are new circuits that are recyclable, electrically conductive, reconfigurable, and self-healing after damage. Yet they retain the strength and durability of traditional circuit board plastics — features rarely found together in a single material.
The new material starts with a vitrimer, a dynamic polymer that can be reshaped and recycled. This versatile material is combined with droplets of liquid metal that do the work of carrying the electric current, the way rigid metals do in a traditional circuit.
The vitrimer synthesis proceeds without the need for a catalyst or a high curing temperature, which enables facile fabrication of the composite materials.
This is a fundamentally different approach from other recyclable or flexible electronics. By combining the high-performance, adaptable polymers with electrically conductive liquid metals, the new circuit holds up under a host of challenges.
A second life
Recycling traditional circuit boards involves several energy-intensive deconstruction steps and still yields large amounts of waste. Billions of dollars of valuable metal components are lost in the process.
To redress this, recycling the team’s circuit board is straightforward and can be accomplished in multiple ways.
The vitrimer circuit boards also can be deconstructed at their end of life using alkaline hydrolysis, enabling recovery of key components such as the liquid metal and LEDs. Fully reusing all components of the conductive composites in a closed-loop process remains a goal for future research.
While it may not be possible to curb the amount of electronics that are discarded by the world’s consumers, this work represents a key step toward keeping more electronics out of landfills.
