Marine-Degradable Paper Coating Offers Sustainable Packaging Solution

Researchers from the Korea Advanced Institute of Science & Technology, in collaboration with Yonsei University, have pioneered a coating technique utilizing biodegradable PVA material. This innovation enhances the quality of paper packaging while concurrently mitigating the adverse impacts of plastic consumption. Their findings were published in Green Chemistry and Food Chemistry.

Plastic pollution is a global issue that must be addressed. Specifically, between 30 % and 50 % of all plastic usage is attributed to packaging.

Usually utilized as coating materials to enhance the low barrier qualities of paper packaging, Polyethylene (PE) and Ethylene Vinyl Alcohol (EVOH) do not break down in the natural environment and instead exacerbate microplastic contamination. While paper packaging is more environmentally friendly, it is weak and lacks important features like strength and moisture resistance. Sustainable solutions are thus required.

In response to this issue, packaging materials composed of bio-based materials and biodegradable polymers have been created. Nonetheless, in most situations, the package's biodegradability rapidly decreases as its performance increases. 

KAIST announced that a collaborative research team, spearheaded by Professor Jaewook Myung from the Department of Civil and Environmental Engineering, Professor Hanseul Yang from the Department of Life Sciences, and Professor Jongcheol Seo from the Department of Packaging and Logistics at Yonsei University, has addressed the challenge of balancing packaging performance with sustainability.

They successfully created a high-performance, marine biodegradable, sustainable paper coating substance.

The paper was coated with boric acid-crosslinked Poly (Vinyl Alcohol) (PVA), a biodegradable material that improves the paper's strength, barrier qualities, and biodegradability. The resultant coated paper performed better than traditional polymers, showing outstanding physical strength and barrier qualities even in humid environments.

The group also thoroughly analyzed biodegradation and biocompatibility to methodically assess the sustainability of the recently created coated paper. To evaluate biodegradation, the marine environment, renowned for having difficult conditions for biodegradability, was simulated.

The team measured the degree of carbon mineralization into carbon dioxide using a bioreactor based on the respiratory system.

It was discovered that, depending on the coating component, the coated sheets achieved 59-82 % biodegradation after 111 days of biodegradation. Using a scanning electron microscope, marine microorganisms were seen breaking down the covering material.

Mouse embryonic fibroblast and human embryonic kidney cells were used to demonstrate the coated paper's strong in-vivo biocompatibility, while animal studies confirmed its in vitro biocompatibility.

To address paper packaging's shortcomings, the collaborative research team developed a coating technique that enhances package performance while maintaining sustainability. The PVA-coated paper, which has been crosslinked with boric acid, eliminates the need for sewage treatment facilities and artificial composting conditions.

Due to its biodegradability in natural environments and low toxicity, this newly coated paper does not contribute to environmental pollution when accidentally discarded. Therefore, it serves as a sustainable alternative to plastic packaging materials.

Professor Jaewook Myung at KAIST, who led the sustainability study of coated paper, said, “The development of a marine biodegradable high-performance paper coating is the result of combining the innovative technologies of three leading research teams in each field. We will continue to develop sustainable materials with excellent performance.”

Through this research, we have developed a sustainable paper packaging technology that can replace non-degradable plastic packaging, and we expect the research outcome will be applied in industry.

Jongchul Seo, Professor, Yonsei University

Seo led the research on the development of high-performance paper coating.

The research was funded by the Korea Research Foundation, the Korea Institute for Agriculture, Food, and Rural Affairs Technology Planning and Evaluation, and others.

Journal References:

Choe, S., et al. (2024) Boric acid-crosslinked poly (vinyl alcohol): Biodegradable, biocompatible, robust, and high-barrier paper coating. Green Chemistry. doi.org/10.1039/d4gc00618f

‌Park, K., et al. (2024) Effect of epichlorohydrin treatment on the coating process and performance of high-barrier paper packaging. Food Chemistry. doi.org/10.1016/j.foodchem.2024.138772