Formation of Zinc Aluminium Layered Double Hydroxides -4(2,4-dichlorophenoxy)butyrate Nanocompisites by Direct and Indirect Methods

4-(2,4-dichlorophenoxy)butyric acid (DPBA) was intercalated between the interlamellae of Zn/Al layered double hydroxides (LDHs). Two methods of intercalation were adopted, (a) direct synthesis by co-precipitation of metal nitrates and DPBA and (b) ion exchange of LDH nitrate with the organic anion. The resulting materials were characterized by x-ray diffraction and infrared spectroscopy. Both methods afford well ordered nanocomposite materials at the same pH and ratio but at different concentrations. The x-ray diffraction patterns showed that the interlayer spacing distances increased from 8.9 Å to 28.7 Å and 29.4 Å for DPBA-LDH synthesized by ion exchange method and by direct method, respectively. The optimum condition were obtained at DPBA concentration of 0.2 M by direct co-precipitation method compared to 0.025 M by ion exchange method. Abstrak Asid 4-(2,4-diklorofenosil)butirik (DPBA) telah diinterkelasikan di antara ruang antara hidroksida berlapis ganda Zn/Al ( LDHs). Penginterkelasian telah dilakukan dengan menggunakan dua kaedah iaitu (a) sintesis secara langsung dengan kopemendakan logam nitrat dan DPBA dan (b) pertukaran ion nitrat daripada LDH dengan anion organik. Produk telah dicirikan dengan menggunakan pembelauan sinar-x dan spektroskopi infra merah. Kedua kaedah tersebut telah menghasilkan sebatian nanokomposit yang tersusun pada pH dan nisbah yang sama tetapi pada kepekatan yang berbeza. Pola belauan sinar-x menunjukkan peningkatan ruang diantara dua lapisan daripada 8.9 Å kepada 28.7 Å dan 29.4 Å bagi DPBA-LDH yang masing-masing telah disintesis dengan menggunakan kaedah pertukaran ion dan secara langsung. Keadaan optimum bagi kepekatan DPBA yang disintesis menggunakan kaedah ko-pemendakan secara langsung adalah 0.2 M manakala 0.025 M bagi kaedah pertukaran ion.