New synthesis of binate herbicide-interleaved anionic clay material: synthesis, characterization and simultaneous controlled-release properties

Abstract

A new synthesis nanohybrid herbicide compound was successfully synthesized by the simultaneous insertion of 2,4,5-trichlorophenoxybutyrate (TBA) and 2-methyl-4-chlorophenoxy acetates (MCPA) as a binate guest anion into the interlamellar space of the host Zn/Al layered double hydroxide (LDH) using the ion-exchange method. Two different basal spacings of 23.1\xa0Å and 23.8\xa0Å were detected by the Powder X-ray Diffraction (PXRD) of the nanohybrid accounting for the presence of two distinct intercalated phases. Direct insertion mass spectroscopy (DIMS), Carbon, Hydrogen, Nitrogen and Sulfur analysis (CHNS), Fourier transform infrared spectroscopy (FTIR), Field Emission Scanning Electron Microscope (FESEM), thermogravimetry analysis-derivative thermogravimetry analysis (TGA-DTG) confirmed that both anions were intercalated to yield a biphasic well-ordered nanohybrid material. The study of the release properties showed that both ions were released, but at different rates, offering the possibility of using this biphasic nanohybrid for the controlled-release of more than one active anionic agent at different controlled rates. The release of MCPA and TBA from the nanohybrid fitted a pseudo-second order model and the material possessed good controlled-release properties. This property demonstrates the potential use of the layered materials as both supply system and reservoirs, particularly when multiple active agents are simultaneously used to shape an organic inorganic host–guest nanohybrid.