Novel Slow-Release Nanocomposite Nitrogen Fertilizers: The Impact of Polymers on Nanocomposite Properties and Function

Abstract

Efficient use of fertilizers, especially nitrogen, is essential and strategic to agricultural production. Among the technologies that can contribute to efficient use of fertilizers are slow- or controlled-release products. This study describes the impact on structure, urea release rate, and function in the field of urea nanocomposites associated with an exfoliated clay mineral prepared using various concentrations of hydrophilic or hydrophobic polymers. The nanocomposites have a high nutrient load (75% by weight), which itself acts as a structural matrix. Our manufacturing processthe extrusion of a plastic mixtureis simple and can be scaled up, allowing granule production without high costs. Nanocomposites were prepared by adding varying amounts (less than 4% by weight) of polyacrylamide hydrogel or polycaprolactone, which influenced mechanical properties and urea release profiles. Nitrous oxide (N2O) emissions in the field were reduced substantially for nanocomposites, whether composed of polyacrylamide hydrogel or polycaprolactone.

Lignin improves release behavior of slow‐release fertilizers with high content of urea

“…A select quantity of Mt in soil can improve the water retention of the soil, helping form a good soil granulation structure, and it can also be used to remove heavy metals and organic pesticides from soil, which can be helpful in agricultural production. However, slow‐release urea fertilizers with lignin and Mt have been reported to have two drawbacks: (1) low mechanical strength and (2) an unexpected relationship between urea content and urea release rate, which means that the fertilizers with a high urea content will not exhibit a low urea release rate. Mechanical strength is a key aspect in the practical application of a fertilizer in the field .…”

Preparation and Properties of a Double‐Coated Slow‐Release Urea Fertilizer with Poly(propylene carbonate), a Sodium Polyacrylate Hydroscopicity Resin and Sodium Alginate

“…Slow‐release fertilizer is a new type of fertilizer which has been extensively studied in recent years . Different types of slow‐release fertilizers are prepared by coating the active soluble nutrient component with a membrane as a diffusion barrier . It means that the nutrient release rate decreases, even far less than the normal release rate of fertilizer in the soil.…”

Analysis of NH3-N Slow Release systems for fiber digestibility of low-quality forage: in vitro approach

“…The second group of nanocomposites was prepared on the basis of MMT/Ur 1:4 formulation, but modified with two different components, polyacrylamide hydrogel (2 wt.%) and paraformaldehyde (1:0.5 urea: paraformaldehyde molar ratio). These nanocomposites were re-named as MMT/Ur 1:4/HG and MMT/Ur 1:4/Pf, respectively, and were prepared following the methodology previously reported by Pereira et al (2015) and Yamamoto et al (2016). The components (urea, montmorillonite, paraformaldehyde, and hydrogel) were weighed separately and then mixed until a homogeneous formulation was obtained.…”

“…A slow or controlled release of urea into the rumen is therefore an essential aspect for rational use of these inputs in feed. Earlier studies by our research group (Pereira et al, 2012;Pereira et al, 2015;Yamamoto et al, 2016) have seen the development of a new class of nanocomposites intended for slow nitrogen release from the simultaneous extrusion of montmorillonite and urea, with further addition of polymers (hydrogel and paraformaldehyde). These materials were tested under agronomical conditions, showing better performance than commercial polymer-coated urea (Pereira et al, 2017).…”