Concept
The issue of effectively disposing of printed circuit board waste (WPCB), which are environmentally hazardous, challenging to recycle, and economically important items, has grown to be a significant environmental challenge due to the ever-increasing amount of electronic garbage (e-waste) globally. Conventional WPCB recycling methods are inefficient and call for demanding processing, like high pressure and heat treatment. The innovative composite material for printed circuit boards (PCB) presented in this paper can be simply disassembled into its component parts and then reused. Additionally, it is simple to detach and reuse the most priceless PCB components (electronic parts made of precious metals) from the printed circuit board. This study highlights the advantages of employing biodegradable polymers as PCB binders for efficient and eco-friendly recycling. PCB manufacture has steadily increased as a result of the explosive expansion in the usage of electronics in various devices, including both electronic devices for home use and electronic devices for monitoring various processes. This has ultimately resulted in a rise in the quantity of outdated and useless circuit boards1. WPCB makes up to 10% of the more than 50 million tonnes of e-waste that are generated globally each year, according to data.
In the electronics sector, PCB is often made of a composite, dielectric basis that serves as a rigid mechanical frame. Copper foil created on one or both sides of the dielectric base is etched to create tracks that are electrically conductive. The dielectric base is created by hot pressing numerous layers of glass cloth or paper that have been saturated with thermosetting resin as a binder. Currently, binders are made from highly hazardous raw materials. The sources used to make these resins are non-renewable. Additionally, contrary to current standards for the safety of chemical processes and materials, PCBs generated from these resins are not oxidized by microbes in the environment.
Overview
The most hazardous, precious, and challenging to recycle components of electronic trash are WPCB, which are made up of a metallic and a non-metallic fraction. Despite the wide range of uses for printed circuit boards, from automobiles and industrial process control systems to mobile phones and home appliances, WPCBs are distinguished by a relatively high content of precious metals and base metals. Additionally, even within the same category of items (such as mobile phones), the amount of metals used can differ by a factor of 10 or more. Since each tonne of WPCBs contains an average of copper, silver, gold, and palladium, and since precious metals can make up more than 80% of the economic value, processing precious metals hold great economic potential.
Currently, the goal of WPCB recycling is primarily to recover high-value metals, with the non-metallic component being landfilled or burned without further recycling. The non-metallic WPCB portion contains dangerous substances that are exceedingly dangerous to human health and can cause cancer, such as poisonous resins and brominated flame retardants. It is important to note that poisonous WPCB compounds can easily leak from landfills into groundwater, contaminating large areas for a long time. The aforementioned dangers have sparked a thorough scientific investigation of WPCB disposal and recycling options.
Scientists are currently working to create new kinds of binders made from renewable raw materials manufactured through chemical and microbiological processes. This is being prompted by the rapid progress in the synthesis and production of new biodegradable polymers. Due to its increasingly varied applications, the study of biodegradable polymers in particular is of special interest. Biodegradable polymers are used extensively in packaging and medicine, and their range of useful applications is growing rapidly. Thermoplastic polymers with mechanical and electrical properties similar to thermosetting resins include polymers based on polylactic acid (PLA) and copolymers of PLA with other hydroxycarboxylic acids. However, these materials are also readily recyclable for further use through chemical and biotechnological processes.
