Abstract:The UV-curable waterborne polyurethane was synthesized by using isophorone diisocyanate (IPDI), polytetrahydrofuran (PTMEG), dimethylol propionic acid (DMPA), and hydroxyl-terminated polystyrene (HTPS) as materials. The rigid phenyl group was introduced into the UV-curable waterborne polyurethane (UVWPU) structure to improve heat resistance and hardness of the coating film, and the product was confirmed using FT-IR. The effects of curing parameter, dosage of DMPA and HTPS on the properties of coating and emulsion stability were discussed. The results show that the storage stability of the emulsion is over 6 months when the amount of DMPA is above 6 %, and the coating film exhibits excellent appearance and good properties when the curing parameter is above 1.35. The weight-loss temperature of 5 % and 10 % is respectively 245 ℃ and 282 ℃, which is higher 32 ℃ and 27 ℃ than the UVWPU without using HTPS modified, and the adhesion and pencil hardness are also improved.