Renewable whey-based hydrogel with polysaccharides and polyvinyl alcohol as a soil amendment for sustainable agricultural application

• Published in: International journal of biological macromolecules 2024-02, Vol.259, p.129056-129056, Article 129056
• Main Authors: Fabian, Dalila Rubicela Cruz, Durpekova, Silvie, Dusankova, Miroslava, Hanusova, Dominika, Bergerova, Eva Domincova, Sedlacik, Michal, Skoda, David, Sedlarik, Vladimir
• Format: Article
• Language: English
• Subjects: Acid whey; Polyvinyl alcohol; Renewable hydrogel; Sustainability; Water retention
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2023.129056

This work describes the preparation of a novel biopolymer hydrogel based on acid whey, cellulose derivatives and polyvinyl alcohol (PVA). The hydrogel was prepared and characterized with the aim of producing an environmentally-friendly soil amendment to increase water retention capacity of the soil. The findings showed considerable swelling properties of the hydrogels depending on the PVA content and crosslinking density. The samples with PVA in a concentration 2.5 % and 5 % were more rigid, the gel fraction increased with a subsequently decrease in their swelling capacity. The hydrogels crosslinked with 15 % of citric acid demonstrated a constant swelling ratio (SR) of around 500 % within 10 swelling/drying cycles. The hydrogels crosslinked with 10 % citric acid and supplemented with 1 % of PVA showed SR of 1000–1400 % caused by less crosslinked polymer network and increased pore volume for water uptake. It was found that hydrogel with a higher gel fraction had a stable structure. Supplementing PVA at 5 % extended the period of decomposition of the hydrogel material by almost 60 % in the soil environment and soil humidity was maintained for longer. Applying 2 % of the hydrogel 5PVA to soil increased the water retention capacity by 19 %. •An environmentally-friendly soil conditioner was prepared for sustainable agricultural applications.•The effect of polyvinyl alcohol on the swelling properties and biodegradability of the hydrogels was evaluated.•Addition of 5 % PVA extended the period of biodegradation of the hydrogel in soil by almost 60 %.•The results show the potential of acid whey to be a source of nutritive whey agents for plants.