Synthesis And Properties Research Of Rosin-based Water–borne Acrylate Emulsion

Environmental problems are increasingly serious and brought to people's attention with Chinese economic level growing.Traditional solvent-based coatings produced a large number of VOC(volatile organic compounds),water-based paint development has made great progress,but there are still many need to improve.Waterborne acrylic emulsion are widely used in the coatings,adhesives and leather and other fields,but also the hot spots of business and institutional research,because of its excellent weather resistance,water resistance and environmental performance.However,the acrylic resin material is a thermoplastic material,thermal stability poor,sometimes hot and cold and brittle phenomenon,and water-based acrylic emulsion contains more water and emulsifier,film forming a long time,and in water resistance and Poor wetting performance.In this paper,seeding pre-emulsification semi-continuous process and emulsion blending method,natural rosin as raw materials,homemade a stable performance of the rosin emulsion;Methyl methacrylate(MMA),styrene(St),ethyl acrylate(EA),hydroxyethyl acrylate(2-HEA)and acrylic acid(AA)as monomers,PS-630 as emulsifier,Initiator and sodium bicarbonate as buffer to prepare rosin-based waterborne styrene-acrylic compound emulsion.The effects of the content of emulsifier,the amount of water,the amount of rosin emulsion,the amount of initiator and the conditions of polymerization on the particle size,emulsion solid content,emulsion viscosity,monomer conversion and stability of the composite emulsion were analyzed and discussed.Finally,the orthogonal experiment was carried out to optimize the amount of emulsifier.Factors affecting particle size Emulsifier > Amount of initiator > Amount of water > Amount of rosin emulsion amount of water > the amount of rosin emulsion.The effects of the amount of emulsifier,the amount of rosin emulsion,the amount of water,the ratio of hard and soft monomer,the temperature of film formation on the properties of the coating were investigated,and analyzed the mechanisms by which these factors have different effects.The greater amount of emulsifier,the greater the water absorption,water resistance worse.Film temperature and glass transition temperature have a significant effect on the film,the higher the temperature,the better the performance,but not too large,so that the mechanical properties of the film worse.The optimum preparation conditions and film-forming conditions of the composite emulsion were determined by the results of the influencing factors of the composite emulsion properties and the coating performance: The polymerization temperature is 80?,the temperature is 85?,the stirring speed is 400-450 rpm,the temperature is controlled at 300-350 rpm,the ratio of hard soft monomer is 1.5: 1,the amount of emulsifier is 5 wt %,The initiator is 0.8 wt %,the amount of rosin emulsion is 25 wt %,and the ratio of water to monomer is 50:40.The rosin-based waterborne styrene-acrylic compound emulsion with excellent performance is obtained.When the film temperature is 60 ?,the prepared film is continuous and transparent.Water absorption of 2.3%,good water resistance,adhesion to 1,pencil hardness of H,the contact angle is 107°.