| This paper describes the emulsion polymerization process, the basic composition and nucleation and reaction mechanism, and then describes the research progress of the modified styrene-acrylic emulsion. It has been studied from the two aspects of cross-linking monomer and functional phosphate-modified styrene-acrylic emulsion. For the applications of the modified styrene-acrylic emulsion, this article focuses on the preparation of water-based with rust anti-corrosion coatings.Using styrene, butyl acrylate, acrylic acid, HEMA, N-MA, DAAM and organo-siloxane monomer as the reaction monomers, self-crosslink-ing modified styrene-acrylate emulsion has been prepared through pre-emulsification technology and semi-continuous seed emulsion polymerization. The influences of the emulsifier type and amount of the emulsifier, emulsifier ratio, the amount of organo-siloxane monomer, the amount of crosslinking monomer, crosslinking monomer ratio on the emulsion performance are discussed. The structure of the polymer emulsion is characterized by infrared spectroscopy and laser particle size analyzer. Meanwhile, a preliminary inquiry of cross-linking reaction mechanism is also conducted. The results showed that the better integrated performance of emulsion can be prepared when the addition amount of compound emulsifier (SDS and OP-10) is4%, SDS:OP-10=1:1, the amount of organo-siloxane monomer is between1%to2%, cross-linking monomer is5%of the total monomer, DAAM:N-MA=3:2, and it is suitable for film-forming substances of wood paints. Functional phosphate ester is prepared through pentoxide and hydroxyethyl methacrylate in a certain temperature and time, and then using infrared spectroscopy to determine the structure of the functional phosphate ester. Styrene, butyl acrylate, acrylic acid and functional phosphate ester are used as the reaction monomers to prepare anti-corrosion emulsion through pre-emulsification technology and semi-continuous seed emulsion polymerization. The influences of the amount of functional phosphate ester, the ratio of soft monomer and hard monomer, the amount of initiator and temperature on the emulsion performance are discussed. The structure of the polymer emulsion is characterized used infrared spectroscopy and differential scanning calorimetry. The results showed that the better integrated performance of emulsion can be prepared when the addition amount of functional phosphate ester is3%, the proportion of hard monomers and soft monomers is1, the amount of initiator is0.4%of the total monomer and polymerization temperature is between75℃to80℃.Using anti-corrosion emulsion as the film-forming substances, tannic acid and citric acid as conversion agent which the proportion of tannic acid and citric acid is1:1, the water-soluble anti-rust paint has been prepared and it can be directly applied to the corroded metal surface without rusting. This anti-corrosion coatings does well in rust conversion, and its film has a excellent performance of resisting from salt water. |
