A kinetic study of thermal degradation of polypropylene

It is shown that a first-order reaction model cannot be applied to describe thermal degradation of polypropylene. The appropriate reaction order was determined to be 0.35 by using the degree of conversion at the maximum degradation rate measured under dynamic conditions. The validity of the reaction order thus determined was verified by similarity of activation energy between the single heating rate plot and the isoconversional plot. The reaction order was also supported by the consistency of the Arrhenius parameters of isothermal degradation with dynamic degradation.