A Study On The Preparation Of High Viscosity Organobentonite

The study is about the preparation of high viscosity organobentonite. Bentonite sample was treated with ion-exchanged and purified firstly. Modification by quaternary ammonium salt followed. Polymer monomer was subsequently added for graft reaction. The product was through filtering and drying finally, and its viscosity'index is up to 6.5Pa.s.The sodium ion-exchange and purification are easy to access with low energy and reagent dosage.Modification tests was carried on some basic quaternary ammonium salt cationic surfactants, such as Octadecyl trimethyl ammonium chloride, octadecyl dimethyl phenmethyl ammonium chloride , hexadecyl trimethyl ammonium chloride, hexadecyl dimethyl phenmethyl ammonium chloride. At the second stage modification, HX-4010, HX-4011 and re-modification reagent A are further studied. Comparing with traditional one stage modificaton, the process is superior in both product performance and reagent usage. Conditional tests on reaction temperature, time, pH, stirring speed were finished too. Feasible flow-sheet was fixed .The two-stage modification process was tested with other samples. Results show improvement correspondingly.By X-Ray diffraction spectroscopy, it is confirmed that montmorillonite's interlayer space is expaned after modified. It shows quaternary ammonium salts and re-modification reagent entering into montrmorillonite's interlayer. By IR absorption analysis, it is concluded that quaternary ammonium salts and the second step modification reagent take place graft copolymerization. Such reaction significantly increases the interlayer space and product's viscosity.