Research progress in steel slag-based functional fillers with high added value in non-building materials field

People not only face the increasing depletion of primary resources, but also the difficult disposal of solid waste caused by consumption of primary resources. On the basis of fully investigating properties of steel slag, the steel slag-based functional filler has been researched and developed according to the characteristics of steel slag. It has been used in the fields of rubber, coatings and plastics, hoping to realize the cross-industry ecological chain and high value-added utilization of steel slag, which has great economic value and important practical significance. Steel slag-based functional filler has the characteristics of strong adsorption, small particle size, and good compatibility with organic systems. Therefore, it is potential to be widely used in rubber conveyor belts, steel structure anti-rust coatings, architectural exterior wall coatings, man-made composite panels and other fields. In this paper, the characteristics of steel slag and the preparation principle of steel slag-based functional fillers were firstly briefly introduced, and then, the situation of steel slag-based functional fillers used as rubber fillers, paint pigments, and plastic fillers was specifically analyzed. Secondly, the characteristics of steel slag-based functional fillers used in rubber composite materials, building exterior wall primers, building exterior wall coatings, and PVC micro-foamed sheets were pointed out respectively in detail. Then, the application limitations of current steel slag-based functional fillers were reviewed. Eventually, it was proposed to optimize the performance of steel slag-based functional fillers and develop multi-solid waste-based synergistic composite functional fillers, which will be the main development directions of steel slag-based functional fillers in the future.