Degradable electronics could be created from corn starch
As we keep buying new gadgets, the mountains of electronic waste keep growing. To help address this environmental and public health threat, Chinese researchers have modified a degradable plastic for use in electronics.
An estimated 50 million tonnes of electronics are thrown out each year. The majority of this waste derives from consumers in the US and Europe, and much of it is shipped to developing countries to be processed and recycled. China, the world’s largest importer of electronic waste, is reporting environmental damage and public health impacts in regions where electronic waste is processed, including Guiyu and Taizhou.
Electronic waste contains components made with lead, cadmium, beryllium, mercury and other potentially hazardous chemicals. Many of these components are toxic or non-degradable and can soak into soil or rivers, polluting a region.
Scientists from Nanjing University of Science & Technology’s school of chemical engineering, led by Xinlong Wang, saw a need to move towards degradable electronic components. The team set about designing a new degradable material, to be used in electronic devices, which would offer manufacturers more eco-friendly options.
They began with polylactic acid (PLA), a degradable polyester that can be derived from corn starch, tapioca and sugarcane. PLA is one of the most highly consumed bioplastics in the world, having versatile uses in the packaging, electronics and automotive industries as well as in 3D printing.
PLA itself is not a good electronic substrate or insulator, and is brittle and flammable. However, by blending PLA with nanoparticles, using established solution-blending and film-casting methods, the researchers were able to create a new material. The result was a transparent film with useful mechanical, electrical and flame-retardant properties.
This material is a promising candidate for future use in electronics. The authors report in Industrial and Engineering Chemistry Research that “the prepared nanocomposites can be used as the substrates and dielectric to make disposable electronics”.