Polyurethane nanocomposites can increase the release control in granulated fertilizers by controlling nutrient diffusion

Author(s)

Bortoletto-Santos, Ricardo ^{[1, 2]} ; Plotegher, Fabio ^[2] ; Majaron, Vinicius F. ^[3] ; da Silva, Marisa G. ^[3] ; Polito, Wagner L. ^[4] ; Ribeiro, Caue ^[2]

Affiliation

^[1] Univ Estadual Paulista Julio de Mesquita Filho UN, Inst Quim, Ave Prof Francisco Degni 55, BR-14800900 Araraquara, SP - Brazil

^[2] Embrapa Instrumentacao, Lab Nacl Nanotecnol Agronegocio LNNA, Rua 15 Novembro 1452, BR-13561206 Sao Carlos, SP - Brazil

^[3] Univ Fed Sao Carlos, Dept Quim, Rodovia Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[4] Univ Sao Paulo, Inst Quim Sao Carlos, Campus Sao Carlos, BR-13566590 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: APPLIED CLAY SCIENCE; v. 199, DEC 1 2020.
• Web of Science Citations: 0

Abstract

We proposed a nanocomposite system based on castor oil-derived polyurethane (PU) for controlling the release of fertilizers by an ion-exchange mechanism. PU coatings modified with less than 5% montmorillonite, a cation exchange material, successfully retarded the nitrogen release from urea granules, with less than 50% of the nutrient released within 18 days of immersion, as confirmed by soil incubation experiments. The same profile was observed for the phosphate release from monoammonium phosphate (MAP) granules coated with PU modified with hydrotalcite (less than 5% by weight), an anion-exchange material. The release times were proportional to the contents of the cationor anion-exchange materials, which exhibited specific correlations with the kind of nutrient released (i.e., cationic or anionic), confirming the diffusion barrier promoted by the PU coating structures. Our results demonstrated that the use of PU nanocomposites can significantly reduce the coating thickness with improved nitrogen and phosphorus release control, opening a new field for the investigation of controlled release fertilizers. (AU)

• FAPESP's process: 18/10448-2 - Development of biodegradable polymer blends in urea / melamine / formaldehyde / polyols system for applications as coating of agrochemicals
• Grantee: Marisa Gomes da Silva
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 16/15482-9 - Development of nanocomposites based on elemental sulfur to convey the micronutrients to the soil
• Grantee: Fábio Plotegher
• Support Opportunities: Research Grants - Innovative Research in Small Business - PIPE
• FAPESP's process: 20/03259-9 - Development of a new kind of biodegradable polymer nanocomposes for application as coating in the slow and controlled release of soluble fertilizers
• Grantee: Ricardo Bortoletto Santos
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 16/10636-8 - From the cell factory to the Biodiesel-Bioethanol integrated biorefinery: a systems approach applied to complex problems in micro and macroscales
• Grantee: Roberto de Campos Giordano
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Thematic Grants
• FAPESP's process: 17/18673-2 - Development and evaluation of acidity buffering systems for the volatilization control of ammonia from urea
• Grantee: Vinicius Ferraz Majaron
• Support Opportunities: Scholarships in Brazil - Scientific Initiation