Research On Acrylic Emulsion Coating Modified With Organic Fluorine And Organic Silicon

A comprehensive description of the definition, the compositions, the functions, the classification and the developmental history of architectural coatings is provided in this thesis. The systematic polymerizing procedure, reaction conditions, initiator and emulator systems, the ratio of soft-hart monomers and the use of surfactants are discussed in depth. The experimental result shows that when the redox initiating system is adopted, the reaction temperature is much lower than that of the heat-decomposing initiating system. As a general rule, the monomer ratio of pure-acrylic emulsion is BA:MMA=4:5 while for the styrene-acrylic emulsion the ratio is BA:St=5:4. The chemical modification of acrylic emulsion with organic silicon and organic fluorine agents and the development of an environmental friendly architectural paining with high performance are emphasized in the context.Acrylic emulsion coating is popular nowadays for its good environmental friendliness, color retain ability, weather resistance, high adhesion and as well as its self-drying ability at ambient temperature. Due to the limitations of inherent thermo plasticity and the lack of jointing points in linear molecules, the polymer can't form net-like structure in three dimensions. Therefore the conventional acrylic emulsion demonstrates poor thermo adaptability. When the temperature is above certain degree, the coating film returns adherent whereas when the temperature is below certain degree, the coating film lost its elasticity and becomes crisp and easily separable from the wall. To optimize the properties of the acrylic emulsion drastically chemical modification with both organic silicon and organic fluorine reagents has been carried out spontaneously. The effect of the type of organ-silicon and organ-fluorine monomers, the amount of the monomers used and the methods administrated on the properties of the acrylic emulsion is studied in detail. The structure of the new emulsion is characterized by FTIR, TG and the surface property of latex film is tested by XPS. The results indicate that the performance of our modified acrylic emulsion is much better than that of both pure and silyl acrylic emulsion in terms of water resistance, adhesive power, and surface durability.A general overview of the manufacture of architectural coating is also included in this thesis. The important factors such as emulsion, pigment and assistant agents on the final quality of paint is discussed extensively. A new emulsion paint modified with organ-silicon and organ-fluorine is synthesized. A variety of tests and examinations conclude that all performance index of this new paint has met or surpassed the criteria of the current national standard (GB/9755-2001).