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Preparation of a citric acid-modified starch/sodium alginate double-layer-coated slow-release fertilizer and its slow-release performance

Polymer Journal (2025)Cite this article

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Abstract

Coated slow-release fertilizers have good slow-release effects, can be effectively utilized, and are important new types of fertilizers. Compared with single-layer coatings, double-layer coatings have more durable slow-release effects. A double-layer-coated slow-release fertilizer (DCSRF) was prepared with urea as the core, citric acid-modified starch and polyvinyl alcohol as the inner coating, and sodium alginate as the outer coating. Compared with the single-layer coated fertilizer (SCSRF), the DCSRF demonstrated superior slow-release effects, releasing 69.2% of the nutrients within 38 days in water. Additionally, adding 2% DCSRF to soil increased its maximum water-holding capacity by 8%. Pot trials revealed that the DCSRF considerably improved target crop growth, including tiller number, plant height, root depth, and leaf width, outperforming the other methods. The DCSRF, which is made from eco-friendly, low-cost, and widely available materials, exhibits excellent water-retention and slow-release properties, offering a promising theoretical foundation for the development of new fertilizers.

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Data availability

The data that support the findings of this study are available from the corresponding author, Hui Li, upon reasonable request.

References

  1. Duan Q, Jiang S, Chen F, Li Z, Ma L, Song Y, et al. Fabrication, evaluation methodologies and models of slow-release fertilizers: a review. Ind Crops Products. 2023;192:116075. https://doi.org/10.1016/j.indcrop.2022.116075.

    Article  CAS  Google Scholar 

  2. Ghumman ASM, Shamsuddin R, Nasef MM, Yahya WZN, Abbasi A, Almohamadi H. Sulfur enriched slow-release coated urea produced from inverse vulcanized copolymer. Sci Total Environ. 2022;846:157417. https://doi.org/10.1016/j.scitotenv.2022.157417.

    Article  CAS  PubMed  Google Scholar 

  3. Salman OA. Polymer coating on urea prills to reduce dissolution rate. J Agric Food Chem. 1988;36:616–21. https://doi.org/10.1021/jf00081a053.

    Article  CAS  Google Scholar 

  4. Salman OA, Hovakeemian G, Khraishi N. Polyethylene-coated urea. 2. Urea release as affected by coating material, soil type and temperature. Ind Eng Chem Res. 1989;28:633–8. https://doi.org/10.1021/ie00089a022.

    Article  CAS  Google Scholar 

  5. Salimi M, Motamedi E, Motesharezedeh B, Hosseini HM, Alikhani HA. Starch-g-poly (acrylic acid-co-acrylamide) composites reinforced with natural char nanoparticles toward environmentally benign slow-release urea fertilizers. J Environ Chem Eng. 2020;8:103765. https://doi.org/10.1016/j.jece.2020.103765.

    Article  CAS  Google Scholar 

  6. Han X, Chen S, Hu X. Controlled-release fertilizer encapsulated by starch/polyvinyl alcohol coating. Desalination. 2009;240:21–6. https://doi.org/10.1016/j.desal.2008.01.047.

    Article  CAS  Google Scholar 

  7. Sofyane A, Ablouh E, Lahcini M, Elmeziane A, Khouloud M, Kaddami H, et al. Slow-release fertilizers based on starch acetate/glycerol/polyvinyl alcohol biocomposites for sustained nutrient release. Mater Today Proc. 2021;36:74–81. https://doi.org/10.1016/j.matpr.2020.05.319.

    Article  CAS  Google Scholar 

  8. Dai R, Woo MW, Chen H, Dang X, Mansouri S, Shan Z. Hydrogel beads based on oxidized corn starch cross-linked with gelatin for tartrazine adsorption from aqueous environments. Polym J. 2017;49:549–55. https://doi.org/10.1038/pj.2017.14.

    Article  CAS  Google Scholar 

  9. Chiaregato CG, Faez R. Micronutrients encapsulation by starch as an enhanced efficiency fertilizer. Carbohydr Polym. 2021;271:118419. https://doi.org/10.1016/j.carbpol.2021.118419.

    Article  CAS  PubMed  Google Scholar 

  10. Naz MY, Sulaiman SA, Ariwahjoedi B, Shaari KZK. Natural carbohydrate polymer coatings for green urea. Surf Eng. 2014;31:486–91. https://doi.org/10.1179/1743294414y.0000000381.

    Article  Google Scholar 

  11. Sarkar A, Biswas DR, Datta SC, Dwivedi BSD, Bhattachayya R, Kumar R, et al. Preparation of novel biodegradable starch/poly (vinyl alcohol)/bentonite grafted polymeric films for fertilizer encapsulation. Carbohydr Polym. 2021;259:117679. https://doi.org/10.1016/j.carbpol.2021.117679.

    Article  CAS  PubMed  Google Scholar 

  12. Zafar N, Niazi MBK, Sher F, Khalid U, Jahan Z, Shah GA, et al. Starch and polyvinyl alcohol encapsulated biodegradable nanocomposites for environment friendly slow release of urea fertilizer. Chem Eng J Adv. 2021;7:100123. https://doi.org/10.1016/j.ceja.2021.100123.

    Article  CAS  Google Scholar 

  13. Cheng J, Liao Z, Hu SC, Geng ZC, Zhu MQ, Xu WZ. Synthesis of an environmentally friendly binding material using pyrolysis by-products and modified starch binder for slow-release fertilizers. Sci Total Environ. 2022;819:153146. https://doi.org/10.1016/j.scitotenv.2022.153146.

    Article  CAS  PubMed  Google Scholar 

  14. Otey FH, Trimnell D, Westhoff RP, Shasha BS. Starch matrix for controlled release of urea fertilizer. J Agric Food Chem. 1984;32:1095–8. https://doi.org/10.1021/jf00125a041.

    Article  CAS  Google Scholar 

  15. Pimsen R, Porrawatkul P, Nuengmatcha P, Ramasoot S, Chanthai S. Efficiency enhancement of slow release of fertilizer using nanozeolite–chitosan/sago starch-based biopolymer composite. J Coat Technol Res. 2021;18:1321–32. https://doi.org/10.1007/s11998-021-00495-9.

    Article  CAS  Google Scholar 

  16. Fu J, Wang C, Chen X, Huang Z, Miu J, Shi L, et al. Preparation and characterization of attapulgite-fly ash–based binuclear slow-release fertilizer encapsulated by eudragit. Agron J. 2019;111:2411–21. https://doi.org/10.2134/agronj2018.12.0753.

    Article  CAS  Google Scholar 

  17. Li H, Wang N, Zhang L, Wei Y, Zhang L, Ma Y, et al. Engineering and slow-release properties of lignin-based double-layer coated fertilizer. Polym Adv Technol. 2023;34:2029–43. https://doi.org/10.1002/pat.6029.

    Article  CAS  Google Scholar 

  18. Liu J, Yang Y, Gao B, Wang W, Cheng D, Yao Y, et al. Hydrophobic-densified high-elastic waste-carton-derived biopolymer-coated fertilizers: enhanced performance and controlled-release mechanism. J Environ Chem Eng. 2023;11:110591. https://doi.org/10.1016/j.jece.2023.110591.

    Article  CAS  Google Scholar 

  19. Liao J, Lin Y, Xu M, Luo Z, Jiang G, Chen F, et al. Preparation of hydrophobic hard gelatin capsules for slow-release fertilizers. Polym Test. 2024;134:108427. https://doi.org/10.1016/j.polymertesting.2024.108427.

    Article  CAS  Google Scholar 

  20. Priya E, Sarkar S, Maji PK. A review on slow-release fertilizer: nutrient release mechanism and agricultural sustainability. J Environ Chem Eng, 2024: 113211. https://doi.org/10.1016/j.jece.2024.113211.

  21. Zhao X, Qi X, Chen Q, Ao X, Guo Y. Sulfur-modified coated slow-release fertilizer based on castor oil: synthesis and a controlled-release model. ACS Sustain Chem Eng. 2020;8:18044–53. https://doi.org/10.1021/acssuschemeng.0c06056.

    Article  CAS  Google Scholar 

  22. Zhou Y, Lei SC, Luo M, Luo H, Luo YX, Han NJ. Study on the preparation method of sodium alginate microspheres. Biol Chem Eng. 2021;7:131–3.

    Google Scholar 

Download references

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 22463006); the National Natural Science Foundation of China (No. 52463015); the Joint Fund between Gansu Provincial Science and Technology Plan Project (Natural Science Foundation) (23JRRA794); the Gansu Provincial Science and Technology Plan Project (Science and Technology Specialist) (24CXGA059); and the Qinzhou District Science and Technology Major Special Project in Tianshui City (2024-NCKJG-4929).

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Authors and Affiliations

  1. State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals, College of Material Science and Engineering, Lanzhou University of Technology, Lanzhou, China

    Hui Li, Haotan Yan, Zijian Xue, Shiyu Wang, Wen Li, Zhenbin Chen & Qiaoli Lin

  2. Keliwei (Hubei) Biotechnology Co., Ltd., Wuhan, China

    Xunhua Liao

  3. Hebei Yadong Chemical Group Co., Ltd, Hengshui, China

    Shuai Zhang

  4. Agricultural Technology Comprehensive Service Center of Qinzhou District, Tianshui City, Tianshui, China

    Jiaqi Luo

  5. Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, College of Chemistry, South China Normal University, Guangzhou, China

    Hong Liu

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  1. Hui Li
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Correspondence to Hui Li.

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Li, H., Yan, H., Liao, X. et al. Preparation of a citric acid-modified starch/sodium alginate double-layer-coated slow-release fertilizer and its slow-release performance. Polym J (2025). https://doi.org/10.1038/s41428-025-01082-0

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  • DOI: https://doi.org/10.1038/s41428-025-01082-0

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