Implementation of Biodegradable Liquid Marbles as a Novel Controlled Release Fertilizer

Abstract

This work demonstrates how liquid marble (LM) technology can be used to effectively encapsulate water-soluble fertilizers within a hard, biodegradable polymeric shell. Due to its high nitrogen content, urea is used as a model compound for encapsulation within marbles fabricated of either polycaprolactone (PCL) or polylactic acid (PLA). The tunable release properties of the marbles are examined by fabricating polymeric shells of varying compositions (PCL and PLA) and thicknesses (28−232 μm), and their associated release profiles are assessed under a range of temperatures (10−40 °C) and pH levels (4−10). It is demonstrated that LMs are beneficial for use in controlled release applications as release profiles can be easily adjusted to meet end application needs. To better understand the underlying mechanisms of the release profiles, a kinetic model is implemented that allows for accurate simulation, and prediction, of the release characteristics under all conditions studied. The controlled and tunable release profiles attained from LMs suggest that they would be appropriate for a wide range of industries and applications.

Preparation, Features, and Efficiency of Nanocomposite Fertilisers Based on Glauconite and Ammonium Dihydrogen Phosphate

“…The key components of CRF are nutrients (often ammonium or phosphates) and inhibitory substances [ 27 , 32 , 33 ]. Various polymers [ 25 , 34 , 35 , 36 , 37 ], organic materials [ 22 , 28 , 38 , 39 , 40 ], minerals [ 41 , 42 , 43 , 44 , 45 , 46 ], and heterogeneous substances [ 44 , 47 , 48 , 49 , 50 , 51 ] can inhibit nutrients in the CRF. Clay minerals (phyllosilicates) are common inorganic materials in the creation slow-release fertilisers [ 41 , 45 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 ].…”

Solid-State Encapsulation of Urea via Mechanochemistry-Driven Engineering of Metal–Phenolic Networks

“…1,3 However, the total utilization of urea by plants is reported to be as low as 30−45% owing to the considerable loss to the environment through leaching and runoff, leading to the eutrophication of water bodies, and through gaseous ammonia and nitrous oxide emissions. 4,5 The poor efficiency of nitrogen use by plants is often due to the lack of synchronicity between nutrient supply and plant needs. Therefore, substantial efforts have been directed toward developing controlled-release urea (CRU) to improve utilization and ease the environmental impact of urea while maximizing crop yield.…”

“…It is estimated that the global population will reach >10 billion people by 2050. , As a result, the increase in food demand imposes a pressing challenge for the agriculture sector and the environment, where fertilizers, particularly urea as the dominant nitrogen fertilizer, play a pivotal role in increasing crop production. , However, the total utilization of urea by plants is reported to be as low as 30–45% owing to the considerable loss to the environment through leaching and runoff, leading to the eutrophication of water bodies, and through gaseous ammonia and nitrous oxide emissions. , The poor efficiency of nitrogen use by plants is often due to the lack of synchronicity between nutrient supply and plant needs. Therefore, substantial efforts have been directed toward developing controlled-release urea (CRU) to improve utilization and ease the environmental impact of urea while maximizing crop yield. − The main strategies that have been used to encapsulate urea for use as CRU include spray coating of urea granules with a wide range of nonbiodegradable polymers (e.g., polysulfone, polyurethane, and polyolefins) and encapsulation of urea nanoparticles within a composite through mixing with biodegradable polymers (e.g., aliphatic polyesters and polysaccharides). − However, these strategies have limitations.…”