Synthesis, optimization, characterization and agricultural field evaluation of polymer hydrogel composites based on poly acrylic acid and micro-fiber of oil palm empty fruit bunch

Abstract

The optimum content of initiator (APS), cross linker (MBA), sodium hydroxide (NaOH) and oil palm empty fruit bunch micro-fiber (OPEFB), were optimized using central composite design method (CCD). Polymer hydrogel composite (PHGC) and plain polymer hydrogel (PHG) were characterized using thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). The influence of OPEFB on biodegradation of PHG was studied. The effect of polymer hydrogel composite (PHGC) on the holding capacity of sandy soil, urea leaching loss rate (ULLR) and okra plant growth were investigated. Statistical analysis of CCD showed a significant model and the highest absorption capacity recorded at 1.53–1.57, 14.24–14.42 and 12.88–12,97 % content for APS, NaOH and OPEFB respectively and 0.16 % for MBA. Biodegradation and thermal stability of PAA hydrogel were enhanced when OPEFB fiber was used. PHGC had a remarkable effect on the holding capacity of sandy soil, ULLR and the growth of okra plants.