Study On System And Properties Of Emulsified Asphalt Modified Polymer Cement Based Waterproof Coating

Building leakage has always been one of the main factors perplexing the development of the construction industry.At present,polymer cement waterproof coating(JS waterproof coating for short)is mainly used to solve the problem of building leakage.The core of traditional JS waterproof coating is polymer emulsion modified cement concrete structure.Although the waterproof effect is obvious,it does great damage to the strength of concrete.The properties of waterproof coatings are basically determined by the properties of polymers,and there are some shortcomings,such as poor water resistance,easy to pan-alkali,inferior ability to resist ultraviolet radiation,expensive and so on.In this paper,the low-cost emulsified asphalt is used to modify polymer cement waterproof coating to address the existing problems.The effects of emulsified asphalt,polymer,cement,filler,aggregate and auxiliaries on the properties of coating and film in waterproof coating system were discussed,and the best proportion was determined;Different methods were studied toantipanalkaliof the coating,and ultraviolet absorbers is used to enhance the ultraviolet resistance of the coating;The mechanism of antipanalkali and UV resistance of coatingare further analysized;The waterproof and water resistance of the coating are improved and the cost of the coating is reduced.It is to provide a new idea and experimental basis for further improving the performance of JS waterproof coating,which is expected to be applied in practice.The work is as follows:First,polymer cement-based waterproof coatingis modified emulsified asphalt are studied.By analyzing and studying the effects of different kinds of emulsified asphalt and polymers on waterproofing,water resistance and mechanical properties of coatings,Nonionic emulsified asphalt(20-30 Weight %)was selected.The best content of styrene-acrylic emulsion is 60-70 W%.When the viscosity of the coating system reaches 700-1200 m Pa.s,the compatibility between emulsified asphalt and polymer can be improved,the delamination of polymer and emulsified asphalt can be restrained,the mechanical properties of the system can be improved,and the long-term waterproof performance of coating can be ameliorated,and it is easy to be in the process of construction.In the second part,the effects of additive such as the number and type of aggregate and filler in the coating system,defoaming agent and compacting agent on the properties of the coating are studied.Appropriate amount of aggregate and filler can adjust the fluidity and bonding strength of coating.Defoaming agent and compacting agent can improve the impermeability and tensile strength of coating;The addition of 0.2%hydrophobic agent can effectively reduce the water absorption of coating;0.5% film-forming auxiliaries can improve the film-forming ability of coating at low temperature,and improve the flexibility and compactness of coating film.The waterproof coating with strong waterproof effect,compact structure and normal film formation at 5? was successfully are prepared,and the function mechanism of each component was analyzed.Finally,the mechanism and measures of anti-panalkali and anti-ultraviolet of paint film were studied.By analyzing the influence of alkali suppressant on alkali evolution in the early and late,alkali suppression agent combined with is more effective in inhibiting alkali evolution of coating.It is pointed out that the proper proportion of alkali suppressant and hydrophobic agent can make the film denser,inhibit the water migration in the film,and present a low water absorption rate,so as to inhibit the water invasion of the film and reduce the late panalkali;Use ultraviolet absorbent can improve the weatherability of the coating,Through scanning electron microscope(SEM)and mechanical test,it indicated that 0.3% UV absorber can effectively inhibit the damage of UV to the coating film.