聚乙烯硅橡胶绝缘材料老化性能的研究

Study on the Aging Property of Polyethylene Silicone Rubber Insulating Material

输电线路表面虽然包覆绝缘材料,但是线路长期暴露在自然环境中,发生老化反应后严重威胁使用效果,因此研究了聚乙烯硅橡胶绝缘材料老化性能。制备聚乙烯硅橡胶绝缘材料,使用热老化方法加速聚乙烯硅橡胶绝缘材料老化,研究老化后的聚乙烯硅橡胶绝缘材料的失重情况、力学性能、结晶度、击穿场强与体积电阻率。测试结果显示,140℃老化处理后的聚乙烯硅橡胶绝缘材料失重情况更严重,断裂伸长率和拉伸强度均更低,弹性模量升高,材料整体失去韧性,结晶度明显降低,击穿场强和体积电阻率均下降明显;80℃老化处理后的聚乙烯硅橡胶绝缘材料失重情况与力学性能较好,经过长时间老化处理后,击穿场强和体积电阻率始终高于140℃老化处理的聚乙烯硅橡胶绝缘材料。因此,说明控制老化温度,能够提升聚乙烯硅橡胶绝缘材料的老化性能。

Although the surface of transmission lines is coated with insulating materials,long-term exposure to the natural environment of the lines poses a serious threat to the using effect after aging reactions.Therefore,the aging performance of polyethylene silicone rubber insulating materials is studied.The polyethylene silicone rubber insulating material is prepared,and the thermal aging method is used to accelerate the aging of polyethylene silicone rubber insulating material.The weight loss,mechanical properties,crystallinity,breakdown field strength and volume resistivity of the aged polyethylene silicone rubber insulating material are studied.The test results show that the weight loss of polyethylene silicone rubber insulating material aged at 140℃is more serious,the elongation at break and tensile strength is lower,the modulus of elasticity is higher,the entirety loses toughness,and there are significant decreases in crystallinity,breakdown field strength and volume resistivity;The polyethylene silicone rubber insulating material aged at 80℃has better weight loss and mechanical properties than that aged at 140℃.After long-term aging treatment,the breakdown field strength and volume resistivity are always higher than the polyethylene silicone rubber insulating material aged at 140℃.Therefore,it is demonstrated that controlling the aging temperature can improve the aging performance of polyethylene silicone rubber insulating materials.