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UPSI Digital Repository (UDRep)
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| Abstract : Universiti Pendidikan Sultan Idris |
| The aim of this research is to synthesize and characterize the nanocomposites and also to determine the controlled release behaviour of 3-(4-hydroxyphenyl)propionic acid (HPP) anion. Zinc layered hydroxide-3-(4-hydroxyphenyl)propionate (ZLH-HPP) nanocomposite was synthesized by direct reaction method. Meanwhile, layered double hydroxide-3-(4 hydroxyphenyl)propionate (LDH-HPP) nanocomposite was synthesized by ion-exchange method. The ZLH-HPP and LDH-HPP nanocomposites physicochemical properties was characterized using powder x-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), carbon, hydrogen, nitrogen, oxygen and sulphur analysis, inductive coupled plasma-optical emission spectrometer, thermogravimetric analysis and derivative thermogravimetry, and field emission scanning electron microscope. Research findings confirmed that two nanocomposites ZLH-HPP and LDH-HPP were successfully synthesized with PXRD pattern of ZLHHPP and LDH-HPP nanocomposites show well order layered structure with basal spacing 25.1 A and 17.7 A respectively. FTIR and compositional studied revealed the presence of the HPP anions between the interlayer of nanocomposites. Result of controlled release study showed that release of HPP anions from both nanocomposites into sodium dihydrogen phosphate solution yielded the highest percentage accumulated release of HPP anions compared to sodium sulphate and sodium chloride solutions. The kinetic study of HPP anions from ZLH interlayer galleries into sodium dihydrogen phosphate, sodium sulphate and sodium chloride solutions was found to be governed by pseudo-second order, parabolic diffusion and first order model respectively. Meanwhile, the kinetic study of HPP anion from LDH interlayer in all solutions was controlled by pseudo-second order. As a conclusion, ZLH-HPP and LDH-HPP nanocomposites were successfully synthesized and intercalation of HPP anions between the interlayer was confirmed by characterization data. Controlled release study of herbicides was governed to one of the kinetic model that has been proposed. The implications of this study explained that the new nanocomposite formulations are highly effective, involve a low production cost and safer for environment. |
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