| With people’s awareness of environmental protection continuously improved more and more people pay attention to water-based ink which goes by the name of the new green printed materials for its low pollution, low volatility, incombustibility, nontoxicity or low toxicity, odorless or low-odor. Currently, the binder of water-based ink is mainly acrylic resin, which has high gloss, excellent stability, weatherability and rheological properties etc. While there is existing defects such as high film-forming temperature, poor back to the viscous resistance, bad water resistance, poor adhesion etc. Therefore to synthesis modified acrylic resin which can overcome these shortcomings has become a common goal. Nano-Si O2/silicone modified acrylate latex has good water resistance, temperature tolerance and weatherability. This is widely used in the fields of inks, coatings, adhesives and leather finishing agents etc. Nowadays the research of nano-inorganic materials and silicone modified acrylate emulsion has become increasingly active for its excellent comprehensive performance and has a great market prospects.In this paper, the two-component acrylic emulsion was synthesized by the method of semi-continuous and seed emulsion with methyl methacrylate(MMA) and butyl acrylate(BA) as main monomer, it contains emulsion A with low glass-transition temperature and emulsion B with high glass-transition temperature. The emulsion A and emulsion B were mixed prior to use. The effects of reaction temperature, the type and amount of emulsifier and initiator, and other factors on the emulsion properties were discussed. The results indicate that the reactive emulsifier SE-10 was chosen as the emulsifier of the emulsion polymerization system, in an amount of 3.0% of the total mass of the monomers, the potassium persulfate(KPS) and sodium bisulfate(SBS) redox initiator system was chosen as the initiator of the emulsion polymerization system, in an amount of 0.5% of the total mass of the monomers, the mole ratio of the KPS to SBS was 2:1. The reaction temperature of the emulsion A was 63~68℃, the mass ratio of the functional monomer acrylic acid(AA) was 2.0%, the lowest rate of gel was 0.48%, the highest rate of conversion of monomers was 98.7%, the latex particles with an average particle size of 118.4nm, the water absorption of the coating film was 15.7%, the glass-transition temperature of the emulsion was 22.8℃. The reaction temperature of the emulsion B was 60~65℃, the mass ratio of the functional monomer glycidyl methacrylate(GMA) was 2.0%, the lowest rate of gel was 0.61%, the highest rate of conversion of monomers was 98.0%, the latex particles with an average particle size of 126.5nm, the water absorption of the coating film was 13.6%, the glass-transition temperature of the emulsion was 99.6℃.The acrylic emulsion A and B were uniformly mixed with a ratio of 1/1 to form a two-component acrylic emulsion, its performance test results showed that the solid content of two-component acrylic emulsion was 48.6%, the viscosity was 630 m Pa.s, the latex particles with an average particle size of 122.8nm, the contact angle was 70°, the film-forming properties was good. It had good dilution stability, freeze-thaw stability and mechanical stability.Based on the technology of synthesis of acrylic emulsion A to modify acrylic emulsion A by the addition of different organic silicon monomer and different forms of nano-Si O2. The results show that the organic silicon monomer selected A-174, in an amount of 1.5%, nano-Si O2 was added in an amount of 2.0% by tetraethylorthosilicate precursor form, the reaction temperature was 63~68℃, the amount of emulsifier was 3.5%, the amount of initiator was 0.5%, the excellent comprehensive performance of nano-Si O2/silicone modified acrylic emulsion A was synthesized. |
PDF Full Text Request