Preparation And Characterization Of High Performance Basic Emulsion For Waterborne Damping Coating

In recent years,noise pollutions have attracted many attentions around world.The application of shock reduction and noise reduction materials can effectively reduce the noise and vibration,but its safety should not be ignored.Both asphalt damping materials and solvent based damping coatings inevitably release toxic and harmful substances in the process of use for a long time.Therefore,water-based damping coatings,which has more environmentally friendly and excellent damping properties,were emerged to respect the environment.Water-based damping coating is composed of basic emulsion,additives,fillers,flame retardants,etc.The damping properties of coatings are mainly determined by the properties of basic emulsions.Hence,basic emulsion with excellent damping performance were expected,which lays a foundation for the preparation of subsequent water-based damping coatings.The main research works and conclusions are as follows:(1)A series of acrylate emulsions with different effective damping temperature range were prepared based on butyl acrylate,isooctyl acrylate,styrene,methyl methacrylate and acrylonitrile as raw materials.The formulation with better low temperature damping performance(-61.15 to 5.80 °C)and wider effective damping temperature range(117.69 °C).(2)The effect of the synthesis methods of polyacrylic acid isooctyl ester latex particles with different particle sizes and its latex particle size on the stability of the emulsion were studied.It was found that a series of monodisperse emulsions(PDI<0.1)with particle sizes from 95 nm to 350 nm can be obtained by varying the amount of electrolyte,dispersion medium,and seed emulsion.The study showed that the latex with particles size of 300 nm have a good stability.There is no appearance of gel after adding the fillers to the emulsion.(3)A series of modified waterborne polyurethane emulsions were synthesized by Polytetrahydrofuran ether glycol,isophorone diisocyanate,dimethylolpropionic acid,1,4-butanediol,etc.Castor oil,styrene and butyl acrylate were used as modifiers.The effective damping temperature range with maximal value can reach 156.13 °C.Then the wide temperat-ure domain of modified waterborne polyurethane emulsion was physically blended with the modified acrylate emulsion,which have good low temperature damping performance prepared in the previous experiment.The results showed that effective damping temperature domain width of the emulsion film was further broadened to 166.8°C.