Preparation method of waterproof and whiting-resistant silicon-acrylic composite emulsion for interior wall latex coatings

Abstract

The invention relates to a preparation method of a waterproof and whiting-resistant silicon-acrylic composite emulsion for interior wall latex coatings. The emulsion comprises the following raw materials: monomers, emulsifiers, initiators such as ammonium persulfate and deionized water. The raw materials are orderly processed through steps of pre-emulsifying the monomer, polymerizing seed emulsion, polymerizing semi-continuous emulsion and finally filtering and discharging. According to the preparation method, vinyl organic silicon, a self-crosslinking system and assistant cross-linking agents are copolymerized with acrylic esters monomers by using pre-emulsification semi-continuous seed emulsion polymerizing method to prepare the silicon-acrylic composite emulsion. Entire preparation process is stable and convenient and is beneficial to achieving mass production. The obtained composite emulsion has the advantages of monomer conversion rate of more than 96%, average emulsion particle size of less than 100 nanometers (nm), good mechanical stability and storage stability, high hardness of film, low lowest film-forming temperature and excellent whiting resistance in water and water resistance.

Description

technical field [0001] The invention relates to a preparation method of a water-based paint, in particular to a preparation method of a water-resistant and anti-whitening silicon-acrylic composite emulsion for an interior wall latex paint. Background technique [0002] With the increasingly stringent environmental protection requirements and people's increasing attention to the quality of the living environment, the content of volatile organic compounds (VOC) has become an important inspection index in the process of interior decoration. At present, traditional solvent-based interior wall paints have been gradually replaced by latex paints in water-based paints. As a film-forming substance commonly used in latex coatings, polyacrylate emulsions have also been extensively studied and applied in recent years. Polyacrylate emulsion has a wide range of raw materials and low price. It not only has excellent weather resistance, gloss retention, adhesion and chemical resistance, ...

AI Technical Summary

Problems solved by technology

The conventional emulsion polymerization process is simple, but siloxane is prone to hydrolysis and polycondensation in the water phase during polymerization, which affects the copolymerization of vinyl organosiloxane and acrylate monomers, and it is difficult to prepare silicone acrylic emulsion with high silicon content

Although the core-shell emulsion polymerization method can endow the emulsion with different properties through different core-shell layers, the operation of this method is complicated, and the process control requirements are relatively strict. When silicone is the core, its surface is embedded by polyacrylate, and the composite resin The performance improvement is limited; when silicone is the shell, the stability of the emulsion is poor, and it is easy to produce two kinds of latex particles, polyacrylate and polysiloxane, and the obtained resin is difficult to take into account the advantages of both

The molecular chains of polyorganosilane and polyacrylate in the silicone-acrylic composite emulsion prepared by interpenetrating network polymerization interpenetrate and intertwine, which can effectively solve the problem of phase separation between silicone and acrylic resin, but the process is also complicated, and the structure and shape of composite particles , the degree of interpenetration of the two, the size of the phase region, etc. are difficult to control, and due to the entanglement of the molecular chains, it is difficult to migrate the silicone molecular chains during the film-forming process of the emulsion, and it is difficult to truly achieve the unity of cost and performance

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