Differential scanning calorimetry as a method for kinetic studies of polymerization.
Part I. Bulk polymerization of methyl methacrylate
Polimery 1997, No 4, 213
Radical bulk polymerization of MMA was studied in the DSC isothermal and in the scanning runs. Methods for evaluation of kinetic parameters from observed data have been described. At low conversions, the overall rate constant and some thermodynamic parameters were evaluated from the DSC isothermal runs (75—90°C) as, e.g., k = 1,75.10-3 (l/mol)0,5/s, enthalpy of polymerization (ΔН =-56,5 kJ/mol), energy and entropy of activation Eη= 86 kJ/mol and ΔS+ = -62,7 J/K.mol, resp., at 80°C. The DSC scan runs were also used to evaluate Eη and ΔS+ the resulting data were compared with those evaluated from the DSC isothermal runs. At high conversions, the polymerization course was found to obey the Sawada equation; the kinetic parameters in the equation were evaluated (Table4).