Allyloxypolyethyleneglycol (APEG) is a non-ionic, bifunctional polyether that combines a hydrophilic polyethylene-glycol (PEG) backbone with a terminal allyl ether group. This product is soluble in water and various organic solvents. It is an important raw material for the new generation of polycarboxylic acid-based high-efficiency water-reducing agents. Polycarboxylic acid-based high-efficiency water-reducing agents synthesized using this raw material have excellent particle dispersion and retention properties, with advantages such as high water-reduction rate, low cement consumption, good strengthening effect, good durability, no rusting of steel bars, and environmental friendliness. It can be applied to high-performance, high-strength (C60 and above) commercial concrete for on-site mixing and long-distance transportation.