Abstract
The ignition properties of PP (polypropylene) and HIPS (high impact polystyrene) as general use plastics, PC (polycarbonate) as an engineering plastic, and ABS (acrylonitril-styrene-butadiene copolymer) were studied. The specimens were placed at a plane view position (position in which the heat source irradiates a plane of the specimen: P-position) and at a side view position (S-position) and ignited by a burner. The critical heat flux (Hc) depended on the shape of the specimen and the excess heat (Q) depended on the kind of polymer at the P-position. On the other hand, at the S-position the Hc depended on the kind of polymer and Q depended on the shape. Thus, we see that fire risk in electrical parts is affected by not only by the kind of polymer but also by the shape of the specimen.
