RAPID COMMUNICATION: Estimation of the aluminum salt effect on homopolymerization
of acrylamide and its copolymerization with acrylic acid by DSC (in English)
Polimery 2006, No 6, 460
The estimation of thermal effects occurring during the homopolymerization of acrylamide (AAm) and acrylic acid (AA) and their copolymerization in aqueous solutions at 40°C in the presence of aluminum salt has been performed on the basis of DSC measurements. The presence of AA in the reaction system reduces the total heat effect of the copolymerization and indicates the reduction of the final conversion. The influence of the aluminum sulfate added in two concentrations (0.04 and 0.33 mol %) and changes in positions of polymerization peak maxima in comparison to the polymerization peaks of the neat monomers were registered. Aluminum sulfate causes retardation of AAm homopolymerization by shifting the position of exothermal peaks to longer polymerization times as compared to the neat homopolymerization reaction. On the other hand the aluminum salt seems to have a beneficial effect on the AA homopolymerization under the experimental conditions. The exothermal peaks of the monomer mixture copolymerizing in the presence of aluminum sulfate were found to be significantly shifted in comparison to those for AAm homopolymerization peaks in neat as well as in AAm/Al salt system.
Key words: acrylamide, acrylic acid, aluminum sulfate, thin-layer polymerization, differential scanning calorimetry
Estimation of the aluminum salt effect on homopolymerization of acrylamide and its copolymerization with acrylic acid by DSC (in English)