Asphalt emulsifier for cold-recycling and preparation method thereof

The invention belongs to the technical field of asphalt pavement cold-recycling, and particularly relates to an asphalt emulsifier for cold-recycling and a preparation method thereof. The preparation method includes the specific steps that tall oil fat acid is slowly and dropwise added into polyethylene glycol and a catalyst for reaction for 4-6 h at the temperature of 140-160 DEG C, and polyethylene glycol toll oil acid ester is obtained; cooling is conducted, epichlorohydrin and amine are added for reaction for 3-6 h at the temperature of 120-140 DEG C, and the asphalt emulsifier for cold-recycling is obtained. Compared with the prior art, according to the asphalt emulsifier for cold-recycling, raw materials are stable in performance and easy to obtain, the preparation technology is simple, requirements for equipment are low, and the asphalt emulsifier for cold-recycling is suitable for mass production. Prepared emulsified asphalt prepared through the asphalt emulsifier for cold-recycling is excellent in stability, the wrapping property of the prepared emulsified asphalt and old materials of different particle sizes is good, adhesiveness is good, a cold-recycling asphalt mixed material is good in durability, pavement performance is excellent, and requirements of actual engineering can be met.