A Montmorillonite Clay as an Efficient and Green Catalyst for Polyether Synthesis (Environment-Friendly Solid Catalyst)
One of the major current challenges before chemists is to develop synthetic methods that are less polluting, i.e., to design clean or 'green' chemical transformations. Green chemistry simply, is the use of chemistry techniques and methodology that reduce or eliminate the use or generation of feedstock, products, by-products, solvents, reagents etc. that are hazardous to human health or the environment (Anastas,Williamson, 1996) . The purpose of this study was to synthesize polyether by green catalysis, based on the ring opening polymerization of cyclic ethers by an environment-friendly solid catalyst (Maghnite-H⁺). “Maghnite” a montmorillonite sheet silicate clay, exchanged with protons to produce “Maghnite-H+” is an efficient catalyst for cationic polymerization of many vinylic and heterocyclic monomers (Belbachir, M. U.S. Patent. 066969.0101 –2001). This solid catalyst can be easily separated from the polymer products and regenerated by heating to a temperature above 100 °C. The effects of the relative amounts of the Maghnite-H+ on the outcome of the polymerization are also discussed. The synthesized polyether was characterized by infrared spectroscopy (IR), 1H-NMR spectroscopy, and GPC.
Keywords - Clay, Green Catalyst, Maghnite-H+, Cyclic Ethers, Ring Opening Polymerization, Polyether.