Three-proofing fabric finishing agent and preparation method thereof

The invention relates to a preparation method of a three-proofing fabric finishing agent, which comprises the following steps: (1) evenly mixing raw material monomers for later use, weighing a composite emulsifier and an acetone-water mixed solvent, and evenly mixing the raw material monomers with the composite emulsifier and the mixed solvent to form a mixed solution; (2) stirring the mixed solution, pouring the mixed solution into a homogenizer, and homogenizing to obtain a milk white preemulsion; (3) dropwisely adding a 10 wt% initiator solution into the preemulsion at 50-90 DEG C; and (4) after finishing the dropwise addition, reacting for 5-10 hours while keeping the temperature, cooling to room temperature, and filtering to obtain the product. In comprehensive consideration of raw material sources, functionality, convenience, economy and the like, the invention has the advantages of simple synthesis, low price, low krafft point, wide temperature limit and the like. The invention also discloses a three-proofing fabric finishing agent produced according to the preparation method.