Application of polysaccharide hydrogels in adsorption and controlled‐extended release of fertilizers processes

Abstract

This article studied the applicability of poly(-acrylamide) and methylcellulose (PAAm-MC) hydrogels as potential delivery vehicle for the controlled-extended release of ammonium sulfate (NH 4 ) 2 SO 4 and potassium phosphate (KH 2 PO 4 ) fertilizers. PAAm-MC hydrogels with different acrylamide (AAm) and MC concentrations were prepared by a free radical polymerization method. The adsorption and desorption kinetics of fertilizers were determined using conductivity measurements based on previously built analytical curve. The addition of MC in the PAAm chains increased the quantities of (NH 4 ) 2 SO 4 and KH 2 PO 4 loaded and extended the time and quantities of fertilizers released. Coherently, both loading and releasing processes were strongly influenced by hydrophilic properties of hydrogels (AAm/MC mass proportion). The best sorption (124.0 mg KH 2 PO 4 /g hydrogel and 58.0 mg (NH 4 ) 2 SO 4 /g hydrogel) and desorption (54.9 mg KH 2 PO 4 /g hydrogel and 49.5 mg (NH 4 ) 2 SO 4 /g hydrogel) properties were observed for 6.0% AAm-1.0% MC hydrogels (AAm/MC mass proportion equal 6), indicating that these hydrogels are potentially viable to be used in controlled-extended release of fertilizers systems.

Recent Development in Applications of Cellulose Nanocrystals for Advanced Polymer-Based Nanocomposites by Novel Fabrication Strategies

“…The value of the maximum compressive stress increased to 4.4 kPa for nanocomposite hydrogels from 2.1 kPa for pure PAM-MC hydrogels. Because of their biodegradability and biocompatibility, these reinforced nanocomposite hydrogels are promising materials for different technological applications, especially in agricultural applications, such as a carrier vehicle for agrochemical controlled release, such as pesticides (Aouada et al, 2010) and nutrients (Bortolin et al, 2012). …”

Organic acid coated-slow-release phosphorus fertilizers improve P availability and maize growth in a tropical soil

“…Although there are many studies that demonstrate the CSRF water dissolution rate (Bortolin et al, 2012;Lubkowski, 2014;Lubkowski et al, 2015;Ahmad et al, 2015) and agronomic efficiency (Pauly et al, 2002;Figueiredo et al, 2012;Silva et al, 2012;Chagas et al, 2015), little is known about the characteristics of organic polymers that could reduce the negative effects of previous fertilizer P contact time with soil on P availability and the consequent growth response by the plant.…”

Polysaccharides as safer release systems for agrochemicals

“…This avoids unnecessary expenses and minimizes the environmental impacts caused by overuse of fertilizers in the plantations. The applicability of poly(acrylamide) and methylcellulose (PAAm-MC) hydrogels as potential delivery vehicle for the controlled-extended release of ammonium sulfate (NH 4 ) 2 SO 4 and potassium phosphate (KH 2 PO 4 ) fertilizers have been reported by Bortolin et al (2012). The addition of MC in the PAAm chains increased the quantities of (NH 4 ) 2 SO 4 and KH 2 PO 4 loaded and extended the time and quantities of fertilizers released.…”