Thermal decomposition and hydrolysis of polyacrylamide-co-tert-butyl acrylate

Hydrolysis and thermal decomposition of polyacrylamide tert-butyl acrylate (PAtBA) copolymer were investigated. Carbon-13 nuclear magnetic resonance (13C NMR) spectroscopy was used to monitor the structural changes of the PAtBA. Hydrolysis of the amide groups occurred only after the complete conversion of tBA. Activation energy for the amide groups of the PAtBA was found to be 86.4 kJ/mol. Gas chromatography was used to identify gas products of the thermal decomposition of PAtBA. Gas analysis showed conclusively the formation of isobutene and carbon dioxide from the tBA groups of the copolymer. Tertiary butanol was found to be the hydrolysis product in the aqueous phase at temperatures from 60 to 130 °C. Kinetics governing the contribution of tBA and amide groups to the total degree of hydrolysis of the PAtBA is presented. An nth order equation was used to check for the hydrolysis reaction order of both the amide and the tBA groups. Analysis of 13C NMR spectra revealed that tBA groups were randomly distributed on the PAtBA copolymer chain.