填料对自固化硅橡胶绝缘保护材料性能的影响

Influence of Fillers on Properties of Self-curing Silicone Rubber Insulation Protecting Materials

以甲基乙烯基硅橡胶为基胶,选取微米级炭黑、氢氧化铝、氮化硼和白炭黑为改性填料,制备多个自固化硅橡胶绝缘保护材料试样。通过对试样的体积电阻率、拉伸强度、断裂伸长率、相对介电常数、介质损耗因数和击穿强度进行测试,研究了不同填料对试样各项性能的影响。结果表明:试样的体积电阻率随炭黑、氢氧化铝和氮化硼添加量的增加而下降,而相对介电常数和介质损耗因数则有所上升。随着炭黑添加量的增加,试样的拉伸强度呈明显的上升趋势,而断裂伸长率则先增大后减小。以各填料单独作用时的最佳添加量为基础制备了改性试样,其工频电气强度相较于纯硅橡胶试样降幅明显,添加白炭黑后则能够有效提高改性试样的工频电气强度。综合各试验结果,确定了具备较好综合性能的自固化硅橡胶绝缘保护材料的配方。

Taking methyl vinyl silicone rubber as base rubber,micron carbon black,aluminum hydroxide,boron nitride,and white carbon black as modified fillers,we prepared several groups of self-curing silicone rubber insulation protecting materials.The volume resistivity,tensile strength,elongation at break,relative dielectric constant,dielectric loss factor,and electric strength of samples were tested,and the effects of different filler addition amount on their properties were studied.The results show that with the increase of carbon black,aluminum hydroxide,and boron nitride addition amount,the volume resistivity of samples decreases,while the relative dielectric constant and dielectric loss factor increase.With the increase of carbon black addition amount,the tensile strength of samples increases obviously,while the elongation at break increases at first and then decreases.A modified sample was prepared on the basis of the best addition amount of fillers alone.Compared with pure silicone rubber,the power frequency breakdown strength of the modified sample decreases significantly,and adding white carbon black can increase the power frequency electric strength of the modified sample effectively.Based on the test results,the formula of self-curing silicone rubber insulation protecting materials with good comprehensive performance is determined.