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Abstract
Acrylonitrile (AN)-methyl acrylate (MA), acrylonitrile (AN)-ethyl acrylate (EA), acrylonitrile (AN)-butyl acrylate (BA) copolymers with and without doping with ferric chloride were prepared by free radical polymerization at 70°C. Mössbauer spectrum shows no reduction of ferric species to ferrous during the copolymerization. TGA studies show that the addition of ferric chloride changes the thermal decomposition pattern of the copolymer. TGA analysis shows that the inclusion of ferric chloride stabilizes the copolymers by 20–25°C. Mössbauer studies of the copolymers heated at 300°C and 500°C for 15 min showed that during the thermal degration, Fe3+ species was reduced to Fe2+ and then finally it formed 
-Fe2O3.
Abstract
Methyl methacrylate /MMA/-n-butyl methacrylate /nBuMA/ copolymer containing anhydrous ferric chloride was prepared by free radical polymerization at 70 °C. TGA studies showed that the addition of ferric chloride increases the thermal stability of copolymer by 90 °C. Mössbauer studies of the copolymer were carried out to determine the oxidation state and environments of iron in the copolymer. Mössbauer studies of the copolymer heated at 150 °C, 300 °C and 500 °C for 1 h showed that during the thermal degradation, no reduction of Fe3+ takes place.
Abstract
Acrylonitrile-styrene /AN-St/ copolymers of different compositions were prepared, with and without ferric chloride by free radical polymerization. It was found using Mössbauer spectroscopy that reduction of Fe3+ to Fe2+ takes place during the polymerization. The addition of ferric chloride and the reduction of Fe3+ was found to influence the thermal stability of the copolymers.
Abstract
A series of mixed oxides and ferrites of iron and cobalt has been prepared by taking iron and cobalt in the atomic ratio 1
0.50, 11.33 and 13.00, respectively. These samples were prepared by calcination of the stoichiometric amount of their respective nitrate salts for 6 h in air at 500±10°C. Characterization of the samples has been carried out using Mössbauer spectroscopy. Percentage formation of 
-Fe2O3 and CoFe2O4 has been determined using the same technique. These results have been supplemented by X-ray diffraction studies. The particle size has been calculated using Scanning Electron Microscopy. the decomposition of 0.5% w/v hydrogen peroxide at 40°C over the catalyst has also been studied.
Abstract
Polyethyl methacrylate /PEMA/ containing ferric chloride was prepared by free radical polymerization at 70°C. Mössbauer studies of the polymer heated at 150°C, 300°C and 500°C for 1 h showed that during the thermal degradation the Fe3+ species are reduced to Fe2+ and the final form is 
-Fe2O3. TGA studies showed that the addition of ferric chloride during the polymerization of ethyl methacrylate increased the thermal stability of PEMA by 40°C. The final decomposition temperature /FDT/ increased by 75°C.
