Poly(styrene peroxide): an auto-combustible polymer fuel

Abstract

Commonly, polymers exhibit extremely slow, candle-like burning, although oxidizers can increase the rate of combustion, as in solid propellants. Polymer degradation occurs before combustion, and being endothermic, demands a continuous supply of energy. However, if a polymer can degrade exothermically, it can sustain degradation and automatically increase the rate of combustion (autopyrolysis). Poly(styrene peroxide), PSP, which degrades exothermically1 is such an exceptional and rare example. We explored the possibility of autopyrolytic behaviour in PSP. Interestingly, it was observed that, once initiated, PSP not only sustains its own degradation, but also supports a flame in air, with a burning rate comparable to that of solid propellants. This makes PSP an ideal candidate for a special fuel, such a fast-burning autopyrolytic polymer being hitherto unknown. Here, in the first reported study on the combustion of a polymeric peroxide, we examine some salient features of the combustion of this unique auto-combustible polymer and potential fuel, and show that the combustion is controlled by polymer degradation.