PC-B Sustainable – Hackster.io

Landfills around the world are increasingly flooded with electronic waste (e-waste). According to the Global E-waste Monitor report, approximately 62 million tons of e-waste were generated worldwide in 2022. This figure is expected to grow to 82 million tons by 2030. Despite the growth, it is officially documented that only about 22 percent of e-waste is collected and properly recycled, leaving much of it unrecorded and likely to end up in landfills . This massive accumulation of electronic waste poses significant challenges to the environment and human health.

Many electronic devices contain hazardous materials such as lead, mercury, cadmium and brominated flame retardants. When these toxins are improperly disposed of in landfills, they can leach into soil and groundwater, posing a serious threat to the environment and human health. Additionally, burning electronic waste releases toxic fumes into the air, contributing to air pollution and respiratory problems for nearby populations.

A major factor contributing to low recycling rates is the fact that the composition of current PCBs makes them difficult to recycle. They are composed of layers of fiberglass, hard plastic, and copper laminated together, along with the electronic components soldered to the board. The layers are very difficult to separate, so the effort required to recycle PCBs is often seen as outweighing the benefits.

A completely new type of PCB, developed by a group led by researchers at the University of Washington, could change that in the near future. With the help of new material, the team succeeded make a printed circuit board which can be dissolved when no longer needed, allowing the electronic components to be easily scavenged for reuse. And the dissolved material itself can be reused to make another PCB.

The PCBs are composed of a durable polymer called vitrimer. High-quality PCB layers can be made from it through a simple process by fusing them with fiberglass plates. But when exposed to a solvent, the vitrimer turns into a jelly-like substance and dissolves. The researchers found that by using this technique they could recover 100 percent of the fiberglass, 98 percent of the vitrimer and 91 percent of the solvent for reuse. Unlike traditional plastics, vitrimer does not break down through recycling, meaning it can be reused indefinitely.

The manufacturing process for these new PCBs is very similar to the process used to make traditional printed circuit boards, so the switch shouldn’t be too challenging for existing manufacturers. Furthermore, experiments showed that the electrical properties of the printed circuit boards were quite good and comparable to those of printed circuit boards made of FR-4, the most commonly used material today. Considering these factors, this type of recyclable PCB could potentially appear in our electronic devices in the future.

When it comes time to recycle a board, it’s a relatively clean and environmentally friendly process. The researchers calculated that recycling the new plates would result in an 81 percent reduction in carcinogenic emissions, compared to FR-4 PCBs. But only time will tell whether these environmentally friendly PCBs can withstand the often difficult conditions that real-world applications face.