Preparation method and performance test of Evotherm pre-wet treatment aluminum hydroxide type warm-mixed flame-retardant asphalt

[Display omitted] •Wet surface modification of aluminum hydroxide flame retardant to increase dispersion compatibility in asphalt.•Modification efficiency is as high as 99% or more.•The oxygen index of this product can be as high as 27.8.•The combination of flame retardant and warm mix saves construction time. In order to better improve the flame retardant effect of flame retardant asphalt and the dispersibility of flame retardant. The inorganic flame retardant ATH was previously surface-modified by the traditional road surface active agent warm mix (Evotherm), and a new type of inorganic warm mix flame retardant was developed. The results show that through the wet modification in this experiment, the modification effect of aluminum hydroxide (ATH) after the wet modification at 50℃, 20 min and 8% Evotherm dosage is good and the modification efficiency is high. The inorganic warm-mix flame retardant particles. It can be evenly dispersed in the asphalt, significantly reducing the agglomeration phenomenon. The particles of the warm-mix flame retardant have good adhesion to the asphalt; the prepared warm-mix flame retardant and a certain amount of hydrotalcite are mixed in the ratio of No. 70 In the heavy road matrix asphalt, 12% by mass of hydrotalcite is combined with 12% by mass of Evotherm modified ATH, and the oxygen index can reach 27.8, which is already a self-extinguishing material with obvious flame retardant performance. SEM analysis shows that the dispersibility of ATH is significantly improved after modification: XRD and FT-IR analysis show that Evotherm is physically attached to the surface of ATH: TGA-DSC analysis shows that the thermal stability of Evotherm modified ATH has been improved.