▎ 摘　　要

NOVELTY - Positive temperature coefficient polymer conductive material comprises 100 pts. wt. polytetrafluoroethylene, 2-6 pts. wt. graphene, 11-17 pts. wt. nanosilica and 0.2-1.5 pts. wt. dibutyl phthalate. USE - The conductive material is useful for self-limited temperature heat tracing cable (claimed). ADVANTAGE - The conductive material has low heat generation performance reduction rate. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing positive temperature coefficient polymer conductive material comprising (i) placing polytetrafluoroethylene masterbatch, graphene and nano-silica into heating and melting device, heating and melting until polytetrafluoroethylene masterbatch, mixing graphene and nano-silica, (ii) mixing dibutyl phthalate, zinc stearate, salicylic acid p-tert-butyl benzene and potassium persulfate, and then placing in the mixture, stirring and mixing, and (iii) feeding mixture obtained in step (ii) into screw extrusion device and extruding mixture, immersing in cooling oil for cooling to 120-150 degrees C, and then removing from cooling oil and cooling in air to room temperature.