Polymerization of methyl methacrylate in water in presence of some egyptian sands and quartz pegmatite

Abstract

AbstractThe polymerization of methyl methacrylate was carried out in water in presence of some Egyptian sands and quartz pegmatite using sodium bisulphite as initiator. The polymerization was performed at 30, 40, 50 and 60°C using initiator concentrations varying from 0.05 to 0.3 mol/l.The overall rates of polymerization increased from 2.0 × 10−5 mol/l·s to 4.8 × 10−5 mol/l·s in presence of quartz pegmatite, to 5 × 10−5 mol/l·s when Natron sand was used and to 6.4 × 10−5 mol/l·s in the presence of Ahram sand, as the concentration of each was varied from 0 to 30 g/l.The effect of change of temperature, initiator and monomer concentration on the overall rate of polymerization was studied.The molecular weights were determined viscosimetrically. It was found that the average molecular weights of the obtained polymers increase with the increase of both monomer and initiator concentrations and decrease with rise of temperature. Ahram sand leads to a higher polymer yield and a lower average molecular weight than in case of Natron sand.The stereoregularity of the obtained polymers was determined with a 60 MHz NMR spectrometer.