抄録
This work is devoted to examine the effect of melting behavior of polymer sample on limiting oxygen index (LOI), whose concept will be utilized to evaluate the safeness of the material bringing into the space environment, currently based on NASA-STD-6001 (TEST 1). Tested samples; PMMA are manufactured by different methods (casting and molding) to show different melting behavior. Relatively thin sample (thickness is 1 mm) is used to fulfill the present purpose. It is found that higher LOI is experienced when the melting behavior is pronounced. This fact indicates that melting sample does not give the conservative results and dripping behavior would generally pronounce the extinction. It would be interesting to model whether the same scenario would be applied to the microgravity environment where no gravity drug is experienced and molten phase grows substantially according to the time. Although the ripping-off disturbance does not exist, radiative heat loss from the surface is pronounced. With this regard, additional combustion mode (molten-layer-enhanced mode) must be taken into account for further modeling study. We will continuously discuss on this issue within JAXA FLARE project.