The invention relates to a method for preparing polyacrylate / nano-SiO2 compound 
coating agent which is suitable for bottom layer 
coating in clothing leathers and instep leathers, by using a reactive emulsifier. The polyacrylate has excellent 
optical stability, 
chemical resistance and favorable 
adhesive property and is widely used as an 
adhesive, a 
coating film-forming agent, a functional film, and a medical 
polymer and in the fields of 
water treatment and the like, but polyacrylate 
emulsion has the defects of 
embrittlement at low temperature, stickiness and 
strength loss at high temperature, easy after tack and the like, which 
restrict the application range and the use value of the polyacrylate 
emulsion. In the invention, the polyacrylate / nano-SiO2 compound coating agent is prepared by substituting conventional emulsifier with reactive emulsifier by utilizing the nanometer effect of an inorganic nanometer material and synchronously adopting a conventional 
emulsion polymerization method and a 
sol-
gel method. The compound coating agent prepared by the invention has fine granules, excellent 
adhesive force, good filling capacity, strong 
water resistance and flexible and transparent formed film, and meanwhile, the damages to the 
human body and the environment, which are caused by the use of large amount of emulsifiers, are reduced.