The invention relates to a semi-conductive shielding material for a 10-220kV electric cable and a preparation method. The semi-conductive shielding material has the advantages of non-crosslinking property, high temperature-resistant class,
low volume resistivity, non
pollution and recycling property.
Polypropylene resin which is used as a substrate is mixed with conductive
carbon black which is used as a conductive medium to form the non-crosslinking semi-conductive shielding material, of which the volume resistivity shall be no more than 10
ohm.cm at the temperature of 20 DEG C, and shall be no more than 20
ohm.cm at the temperature of 90 DEG C. The semi-conductive shielding material has the beneficial effects that the conductive property and
heat stability of the shielding material are improved; because the
polypropylene resin has good
mechanical property and high temperature-resistant class, the
polypropylene resin can work in the environment at the temperature of -20 to 95 DEG C for a long time under the condition of no crosslinking; for the semi-conductive shielding materials for medium, high and ultrahigh-
voltage electric cables, the characteristics of high temperature-resistant property, non-crosslinking, environment-friendly and recycling properties,
low resistance and
heat stability are realized; when the semi-conductive shielding material is applied to the electric cable products, the
electric field equalizing effect is improved, the local
discharge is prevented, the reliability in running of
electric cables is improved, and the service life is prolonged.