| The synthetic process of silicone-acrylic latices was optimized, and the latices containing functionalized silicone-acylic particles were synthesized in terms of structure design of macromolecules and latex particles by the method of emulsion copolymerization. The particles include: animated silicone-acrylic particles, reactive silicone-acrylic latex particles, self-assembled latex particles, nanosize latex particles, core-shell structured latex particles and hybrid of nanosize silicon dioxide and silicone-acrylic latex particles. High performance latex coatings were obtained using these functionalized silicone-acrylic lattices, and their applications were investigated.Organosilicon modified acrylic latex were synthesized by free radical copolymerization of MMA, BA, AA or MAA with vinyl organosilicone monomers, then grafted with polyhydroxysiloxane. Tg, particle size and its distribution, MFT and morphology of particles of the copolymer latex were characterized. The grafting effect was greatly improved by optimizing the synthetic process and choosing suitable organosilicone monomers.The structure and category of the selected vinyl organosilicone and the pendant polysiloxane have a significant influence on the properties of the latex films, such as hardness, adhesion, impact resistance, stain resistance and ultraviolet aging resistance. The experimental results indicated that the pre-crosslinking density of the silicone-acrylic resin and the chain length of the pendant polysiloxane have a significant influence on the properties of the latex films. The film formation process and mechanism were also investigated.Methods of preparing coatings with low VOC content and improving the performance of the film formed from the silicone-acrylic latices have been further investigated. Silicon-acrylic latices with different particle distribution, Tg and crosslinldng density were synthesized, and blended in order to improve the film forming property of the latices and mechanic properties of the films. The latex exhibits good film forming property and mechanic properties when the blend ratio of soft latex and hard latex is about 60: 40. The film formation process and mechanismof the blended latex were investigated. The silicon-acrylic latices with core-shell structures were prepared by means of a "two-stage" emulsion copolymerization. The effect of constituents and proportion of core and shell parts on the properties of latex film were investigated, and their applications in water-borne wood coatings and elastic coatings were explored. The results indicate that wood coating and elastic silicon-acrylic coatings with good performance and zero VOC content can be prepared by suitable design of structure of silicon-acrylic latex particles.Functional nanosize latex particles were synthesized through (micro) emulsion copolymerization of BA/MMA/MAA with DMAEMA or polymer surfactant of chitosan. Core-shell structured latex and film were prepared through the self-assembly of functional nanosize latex particles. The application of self-assembly latex particles in the latex coatings was investigated. The process of film formation and the structures of the latex film can be controlled and optimized through the self-assembly of the latex particles to improve the film properties. Emulsion copolymerization of MMA/BA/MAA with chitosan as polymer emulsifier was studied and the reaction mechanism was investigated. TEM and AFM were employed to study the self-assembly behavior of the chitosan based latex particles. The film formed from the chitosan based latex through self-assembly process exhibit good film forming property and mechanical properties.Hybrid of surface treated nanosize silicon dioxide with silicone-acrylic latex were prepared through in situ polymerization (ISP), grafting reaction (GR), electrostatic coupling(EC), electrostatic repulsion (ER) and soap-free emulsion polymerization (SFEP). The results showed that the ER method and SFEP method could obtain hybrid with better stability. The film properties of the silicon-a...
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