【目的】获得兼具低黏度和良好耐碱性的羟基丙烯酸分散体。【方法】以丙烯酸丁酯（ BA）为软单体，苯乙烯（ St）、甲基丙烯酸甲酯（ MMA）为硬单体，着重调整羟基单体甲基丙烯酸羟乙酯（ HEMA）、甲基丙烯酸羟丙酯（ HPMA）、丙烯酸羟乙酯（ HEA）、丙烯酸羟丙酯（ HPA）的配比，探究羟基单体组合的种类、含量对分散体的粒径、黏度、外观的影响，以及对水性双组分聚氨酯涂层的光泽、硬度、耐乙醇擦拭、耐碱性的影响。【结果】羟基单体组合为 HEA/HPA，HPA在核组分羟基单体中的含量为 25%时，所制备的羟丙分散体黏度降低至 464. 4 mPa·s。所制备涂层在 5%NaOH溶液中浸泡 8d不起泡不变色，耐醇擦拭可达 220次以上。光泽（20°/60°）达到 82. 4/92. 5，硬度为 2H。【结论】复合型羟基单体构成的“亲水核 -疏水壳”结构能够有效降低分散体的黏度和粒径，分散体稳定性良好，呈乳白色，泛蓝光。 HEA与异氰酸根反应活性高，涂层交联致密，耐碱性和耐溶剂擦拭性能更佳；核组分中 HEA/HPA质量比为 3∶1能够最大程度保留该优势的同时大幅降低施工黏度，弥补了使用单一的羟基单体带来的缺点。

［Objective］To obtain hydroxyacrylic dispersions with both low viscosity and excellent alkali resistance.［Methods］Using butyl acrylate（BA）as the soft monomer，styrene（St）and methyl methacrylate（MMA） as hard monomers，we focused on adjusting the proportion of four hydroxyl-containing monomers［hydroxyethyl methacrylate（HEMA）， hydroxypropyl methacrylate（HPMA）， hydroxyethyl acrylate（HEA） and hydroxypropyl acrylate（HPA）］ to prepare hydroxyacrylicdispersions. The effects of type and content of four hydroxyl monomer combinations on the particle size， viscosity and appearance of dispersion were investigated. Additionally，their impacts on properties of waterborne two-component polyurethane coatings，such as gloss，hardness，ethanol wipe resistance，and alkali resistance were evaluated.［Results］When the hydroxyl monomer combination was HEA/HPA with HPA accounting for 25% of the hydroxyl monomers in core，the viscosity of the prepared hydroxyacrylic dispersion was reduced to 464. 4 mPa·s. Furthermore，the prepared coating does not bubble or change color after being soaked in 5%NaOH solution for 8 days，its ethanol wipe resistance exceeded 220 cycles. The 20°/60° gloss values reached 82. 4/92. 5，with a hardness of 2H.［Conclusion］ The "hydrophilic-core hydrophobic-shell" structure composed of composite hydroxylmonomers can effectively reduce the viscosity and particle size of dispersion，which exhibits goodstability with a milky white appearance and a blue light. HEA has high reactivity with isocyanategroups，leading to a densely crosslinked paint film with better alkali resistance and solvent wiperesistance. A mass ratio of HEA to HPA of 3∶1 in the core component maximizes the retention of theseadvantages while significantly reducing the application viscosity，thus overcoming the drawbacks caused by the use of a single hydroxyl monomer.