Nanoencapsulation of intercalated montmorillonite-urea within PVA nanofibers: Hydrogel fertilizer nanocomposite

This study describes the preparation and characterization of nanofibers with poly(vinyl alcohol) (PVA) as the wall matrix to encapsulate montmorillonite (MMT) clay and intercalated MMT-urea nanocomposite using an electrospinning technique. Nanofibers encapsulated with (1-5%, w/w) MMT clay were successfully produced and characterized in relation to morphological, spectroscopic, structural, surface, and thermal properties. The electrospinning conditions for voltage, flow-rate, and emitter to collector distance were 20 kV, 0.5, and 0.25 mL/h, and 10 cm, respectively. The surface roughness increased from 43.5 (empty fibers) to 56 nm in the PVA/MMT-3% and bead-less nanofibers were formed with the maximum diameter distribution and mean diameter value of 45-80 and 62 nm, respectively. The d-spacing was increased significantly from 1.004 in MMT to 1.684 nm in MMT-urea, indicating the intercalation of urea occurred successfully. Furthermore, elemental analysis results showed that the intercalated MMT-urea contained 30.4% nitrogen. (C) 2017 Wiley Periodicals, Inc.