Physical aspects of polymer combustion and the inhibition mechanism

The characteristics of polymer combustion were studied. The contributions from the conductive, convective, and radiation components of the total heat flow from the flame to the polymer surface were determined. The influence of inhibitors on the rate of chemical reactions in the preignition zone and on the rate of heat and mass exchange between the flame and the burning surface was estimated. It was shown that a change in the heat balance and heat and mass exchange accompanied by changing the optical properties of the flame and burning surface has a pronounced effect on the combustion rate at the flame edge. The formation of a protective coke layer reduces heat flow to the surface of a nonreacted polymer, leading to a decrease in the rate of evolution of the volatile combustible polymer-destruction products into the gas phase. As a result, the flame temperature decreases and it is extinguished.