The Self-Heating Carbon Nanofiber Polymer Composite and its Applications in Deicing and Snow Thawing of Pavement

A carbon nanofiber-based conductive polymer (CNFP) film was fabricated by multiscale carbon nanofibers (10-200. nm) in an in situ filtrating casting process; due to the well-connected hierarchical microstructures and strong-wrapped assembling among carbon nanofibers, the as-prepared CNFP presents excellent electrical conductivity, high thermoelectric performance, and good mechanical properties. And the resistivity of the CNFP exhibited piecewise linear temperature-dependent characteristics within a certain temperature range (0-280. °C). Furthermore, based on excellent electric and thermoelectric properties, CNFP was employed as an electric heating element to develop a novel self-deicing road system. This CNFP-based deicing system consists of CNFP as thermal source, an AlN-ceramic insulated-encapsulation layer, a multiwalled carbon nanotube (MWCNT)/cement-based thermal conduction layer, and a thermally insulated substrate. Additionally, the MWCNT/cement-based composite, which was filled with 3% by weight MWCNT, was proposed as the thermal conduction layer because its thermal conduction properties are superior to those of cement with other fillers and to those of common cement-based composites. To ensure the efficient operation of the CNFP, an AlN-ceramic wafer (0.5. mm) was employed as the electroinsulated layer because of its favorable insulating and thermoconductive properties. The constructed system was applied in deicing and field snow-thawing studies, in which the effects of ambient temperature, heat flux density, and ice thickness on the deicing and snow-thawing performance of the self-deicing system were investigated. The efficiency, repeatability, cost, and feasibility of the self-deicing road system in both deicing and snow-thawing applications were analyzed. Indices for evaluating the deicing or snow-thawing performance of the self-deicing road system were proposed, and the optimal values for each parameter are presented. The results demonstrate the promise of CNFPs as a heating element of self-heating pavement in wide applications in deicing or snow thawing for infrastructures, including pavement, highways, airports, and bridges.