Abstract: Irradiation-crosslinked polyolefin composites were prepared by ethylene-vinyl acetate copolymer with intumescent flame retardant （IFR）of modified pentaerythritol as charforming agent through melt blending, and their flame retardant performance, electrical properties and thermal stability were investigated by limiting oxygen index, high resistance meter, breakdown tester and thermogravimetic analysis. The results indicated that, when 40 wt % of the complex flame retardants was introduced and the irradiation dose was less than 90 kGy, the resulting EVA/IFR-MPER systems achieved an improvement in flame retardancy by 1.5 %. Furthermore, their breakdown field strength, volume resistivity, maximum decomposition temperature and carbon yield at 600 ℃ increased by 2.2 MV/m, 0.6×1013 Ω·m, 4.43 ℃ and 8.52 %, respectively.

Key words: modified pentaerythritol, ethylene-vinyl acetate copolymer, irradiation, flame retardant