Abstract：By comparing the half time halved in the aerosol concentrations needed by particles in various granularity ranges at 3 different conditions including natural coagulation, water spraying and waterborne polyurethane spraying, the corresponding coagulation coefficients were calculated, coagulation and removal efficiency of simulative powdery aerosol particulates with waterborne polyurethane spraying in room were studied. The results show that comparing with the nature coagulation and water spraying, the half time is shortened by 35.3% and 40.6% after waterborne polyurethane spraying at the granularity range from 0.6 to 40.0 μm, the half time is shortened by 10.5% and 26.2% at the granularity range from 2.0 to 105.0 μm.

Keywords：waterborne polyurethane; spraying; aerosol; coagulation; half time