无卤阻燃EVA电缆专用料的配方优化

通过基体树脂复配、自制相容剂(E-g-M)增容以及E-g-M与三元乙丙橡胶(EPDM)并用等途径对乙烯-醋酸乙烯酯共聚物(EVA)/氢氧化镁(MH)/微胶囊化红磷(RP)无卤阻燃电缆料(EMP)性能进行了优化.结果表明:EVA与高密度聚乙烯(HDPE)复配可有效提高EMP电缆料的拉伸强度,EVA与HDPE的质量比为3:1时,EMP/HDPE电缆料的拉伸强度可由7.2 Mpa提高到9.7 Mpa;当在EMP/HDPE电缆料中添加12份E-g-M时,EMP/HDPE电缆料的拉伸强度由9.7 Mpa增至12.8 Mpa,冲击强度由26.5 kJ/m~2升至29.4 kJ/m~2,断裂伸长率由63.7%增至97.8%,E-g-M对EMP/HDPE电缆料起到了同时增强、增韧的作用;当EMP/HDPE/E-g-M电缆料中加入5份EPDM时,EMP/HDPE/E-g-M电缆料的韧性得到了进一步提高,冲击强度和断裂伸长率分别增至35.8 kJ/m~2和162.2%,并且两者的加入对EMP电缆料的拉伸性能、阻燃性能及加工性能影响较小.对照低烟无卤阻燃护套料的技术性能标准(YD/T 1113-2001),EMP/HDPE/E-g-M/EPDM电缆料的力学性能和阻燃性能均高于该标准.

Optimizing Formula of Special Halogen-Free Flame Retardant EVA Cable Compound

The properties of halogen-free flame retarding ethylene-vinyl acetate(EVA)/magnesium hydroxide(MH)/microencapsule red phosphorus(RP)cable compound(EMP)were optimized through mixing of matrix resins, self made compatibilizer(E-g-M)and cooperating E-g-M with ethylene propylene diene monomer(EPDM). The result showed that mixing EVA with high density polyethylene(HDPE)could improve the tensile strength of EMP. When the mass ratio of EVA and HDPE was 3:1, the tentile strength of EMP/HDPE cable compound could increase from 7.2 Mpa to 9.7 Mpa. Adding 12 phr E-g-M to EMP/HDPE cable compound, the tensile strength of EMP/HDPE cable increased from 9.7 Mpa to 12.8 Mpa, the impact strength increased from 26.5 Kj/m~2 to 29.4 kJ/m~2, the elongation at break raised from 63.7% to 97.8%, which demonstrated E-g-M had a role of enhancing the strength and toughness of cable at the same time. When adding 5 phr EPDM to EMP/HDPE/E-g-M, the toughness of the cable compound had further improvement, its impact strength and the enlongation at break increased to 35.8 kJ/m~2 and 162.2%, respectively. Cooperating E-g-M with EPDM had slightly influence on the tensile strength, flame retardant performance and processability of EPM cable compound. Compared with the standard of low smoke halogen-free flame retardant cable compound, the mechanical properties and flame retardant performance of EMP/HDPE/E-g-M/EPDM cable compound were all higher than those of the standard of YD/T 1113-2001.