The Effect of Pressure on the Ceiling Temperature in the Bulk Polymerization of Isobutyraldehyde

The bulk polymerization of isobutyraldehyde was studied at 17-32°C and 5700-7700 kg/cm2 to determine the ceiling temperature. The ceiling temperature which was determined by extrapolating the yields under various reaction conditions to the zero yield increased from 17°C at 5680 kg/cm2 to 32°C at 6560 kg/cm2. The thermodynamic quantities of the polymerization were determined from the volume change of the polymerization and the pressure coefficient of the ceiling temperature. At 25°C and 6160 kg/cm2, the heat of the polymerization was -3.3 kcal/mol and the corresponding entropy change was -11e. u.