Green In-Mold Electronics Using Biopolymers

The concept of In-Mold Electronics (IME) is an emerging technology in which flexible electronic circuits are integrated into plastic parts during the molding process. Several industries such as automotive and healthcare are using this technology due to its lightweight, cost-effective, and aesthetically pleasing features. The increasing demand for these products contributes to the growing problem of electronic waste (E-waste) at the end of life. In this work, the injection molded polymer is replaced by a biopolymer. Biopolymers are typically derived from renewable resources such as plants or microorganisms. By incorporating biopolymers, we can potentially minimize the environmental impact associated with electronic waste:
• Electronics production will have a lower ecological footprint in terms of energy consumption and CO2 footprint. 
• The biopolymer can be separated from the flexible circuit and components by solvolysis.
• Copper and other (precious) metals can be recycled.
• Components can potentially be reused.
In this study, a polyimide-copper (PI/Cu) flexible circuit was embedded into polylactic acid (PLA) using injection molding technology. Polylactic acid (PLA) is a bio-based and biodegradable thermoplastic derived from sugarcane or corn. The technology was approved by showing the functionality of two different types of test circuits. First a demonstrator in which LEDs were powered wirelessly by an NFC antenna and chip. The NFC chip and LEDs are soldered on the flexible circuit foil. Second, a circuit with zero-ohm resistor components assembled on the flexible foil.