Implementation of Biodegradable Liquid Marbles as a Novel Controlled Release Fertilizer
Rebecca V. McQuillan, Geoffrey W. Stevens, Kathryn A. Mumford
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.