| The blends of EVA filled with talc, calcium carbonate, and glass ball (GB) have been photoinitiated crosslinked by UV irradiation in the presence of benzophenone (BP) as photoinitiator and triallyl isocyanurate (TAIC) as crosslinker. The various factors affecting the crosslinking process and the related properties have been studied by gel determination, heat extension test, mechanical measurement, and thermal aging test. The results show that the EVA/talc, EVA/CaCO3, and EVA/GB blends filled with 25 phr inorganic filler can be photocrosslinked to gel content of about 80 wt% by 5 s UV-irradiation under optimum conditions, which is sufficient for many applications. The final gel content level and crosslinking homogeneity are in the order of EVA/GB > EVA/talc > EVA/CaCO3. The data from mechanical measurements and thermal aging test give evidence that the mechanical and thermal aging properties of photocrosslinked EVA/talc, EVA/CaCO3, and EVA/GB samples are much better than those of the unphotocrosslinked one.Secondly, metal powder as a synergistic agent used in the flame retardant system of polypropylene (PP)/ammonium polyphosphate (APP)/pentaerythritol (PER). The corresponding performance of flame retardant was investigated by limiting oxygen index (LOI). Breaking strength/elongation of break testing expressed the mechanical properties and volume resistivity testing used to detective the electric insulation character. The results show that the 2 phr copper powder can increase LOI from 30 to 33 at 35 phr total additives content. Mechanical property and volume resistivity was compared that metal powder change tensile strength and elongation at break little, but decrease the insulation character seriously. 2 phr copper powder reduce the volume resistivity from 1016Ωto 1014Ω, and same additive content aluminum powder make the biggest variation,lower it to 1011Ω.
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