PREPARATION OF MAGNETIC/SILICA/QUARTERNARYCHITOSAN BY SOL-GEL METHOD AND ITS STABILITY IN VARIOUS pH MEDIUM

Abstract

This research aimed to study SiO2/quaternary-chitosan-coated magnetic material synthesis using the sol-gel method through two synthetic routes. The step of Route 1 was the methylation of the amine group on chitosan using methyl iodide and sodium hydroxide with dimethylformamide : water (1:1) as a solvent at room temperature for 48 hours to produce trimethyl chitosan. The next step was the sol-gel reaction. The magnetic was coated with silica and then added to the trimethyl chitosan solution that has reacted with (3-glycidyloxypropyl)trimethoxysilane as a crosslinker. Whereas Route 2 was the opposite of route 1, magnetic coating with chitosan silica was carried out first through the sol-gel reaction, followed by the methylation reaction. The synthesis results were characterized by their functional group, structure, crystal size, magnetic properties, and morphology. The Fe3O4/SiO2/quaternary-chitosan material was successfully synthesized, as indicated by the increase in the specific absorption band for C-H methyl and the decrease in the N-H amine absorption. Route 1 produced material with more quaternary ammonium groups and porous surface but inhomogeneous, while Route 2 produced thicker magnetic coatings. Both materials had stability in the range of pH 3-6 so that they could be applied as adsorbents for anionic compounds in this range.

Modification of chitosan-coated magnetic material with glycidyltrimethylammonium chloride and its application as heterogeneous base catalyst for levulinic acid esterification

“…Unique points of this compound are that chloride ions at the quaternary ammonium cation are known to act as a Lewis base site, and an epoxide group is usable to fix this compound tightly to support materials through a covalent bond. As a support material for GTMAC, magnetite/silica, 21 chitosan, 22 and polyvinyl alcohol (PVA) membranes 23 have been investigated. Among them, chitosan is one of the most attractive materials because of its high biocompatibility, biodegradability, and environmentally friendliness.…”

Preparation and Characterization of Magnetic Material/Chitosan Composite Modified with Glycidyl-Trimethylammonium Chloride

“…GTMAC can link with other materials through chemical reactions and ring opening of the epoxide group [11][12]. Previous studies have investigated the covalent bonding of GTMAC to polymeric materials.…”