The polymerization of propylene under high pressure

Abstract

The bulk polymerization of propylene, with benzoyl peroxide as the initiator, was studied at the pressures of 2, 800, 3, 400 and 4, 000kg/cm^2, and at the temperatures of 80, 90 and 100℃, respectively. It was found that the rate of polymerization was always accelerated by increasing pressure and temperature. From the initial rates, the activation volumes, the activation energies and the activation entropies were calculated and the following values were obtained : ΔV≠=-9.0～-12.7cm^3/mole. E=11.9～12.3kcal/mole and ΔS≠=-46.4～-42.0 e.u. The polymer obtained was a paste-like material, being easily soluble in benzene and cyclohexane at room temperature. It was concluded from the infrared spectrum that the polymer was the atactic polypropylene with low degree of polymerization.