UV Radiation Could be the Key to Recycling Disposable Diapers Efficiently

Disposable diapers contribute significantly to the world’s waste problem, primarily due to their challenging recyclability. Nevertheless, there is a fresh method that can recover the “superabsorber” polymer used in the diaper liners, even when they are soiled.

Ultraviolet light presents a promising avenue for revolutionizing the recycling of disposable diapers, addressing the pressing environmental concerns associated with diaper waste. This innovative approach can significantly reduce the environmental impact of disposable diapers and contribute to a more sustainable future.

The majority of disposable diaper liners consist of a polymer called sodium polyacrylate, which undergoes a transformation from a dry state to a hydrogel as it soaks up liquid.

Challenges of Conventional Recycling Methods

In previous attempts to recycle this material, it involved immersing it in a strong acid, heated to 80 ºC (176 ºF) for approximately 16 hours. This method aimed to disassemble the interconnected polymer chains that form the gel, making them available for recycling. However, due to the significant time and energy requirements of this process, it has seen limited use.

In the quest for a more efficient solution, researchers at Germany’s Karlsruhe Institute of Technology experimented by wetting sodium polyacrylate diaper liners with water and exposing them to ultraviolet light from a 1,000-watt lamp at room temperature. Within just five minutes, the polymer gel transformed into a liquid and was collected. Using established procedures, the scientists then converted this liquid sodium polyacrylate into an adhesive and a thickening agent for dyes.

“The light breaks the bonds connecting the polymers,” clarified Professor Pavel Levkin from Karlsruhe. “Subsequently, these bonds become so relaxed that they disperse in water and transform into liquid strands. This UV light method is approximately 200 times faster than the acid-based approach.”

Promising Prospects for Recycling Used Diaper Liners

Moreover, although the experiments used clean diaper liners, the researchers are confident that the method should function equally effectively with used liners.

Levkin expressed, “We’ve identified a hopeful approach for recycling superabsorbers. This has the potential to substantially diminish environmental pollution and promote a more sustainable application of polymers.”

A paper detailing this research was recently published in the journal Applied Materials and Surfaces.

Read the original article on: New atlas

Read more: A Green Living Environment Does Not Protect Children Against Eczema