Common knowledge of coatings: preparation methods and characteristics of silicone acrylate emulsion in silicone acrylic emulsion coatings

The core tip: because silicone monomers and resins are easily hydrolyzed in water, it is difficult to prepare emulsion At present, there are three kinds of preparation methods of silicone acrylate emulsion (commonly known as silicone acrylic emulsion) (1) Polymer post emulsification (physical method) Firstly, organic resin or modified silicone resin was prepared, and water was used as dispersing medium, emulsifying agent was added to emulsify under the action of high shearing force This method can prepare stable emulsion only when the molecular weight is small, because of its small molecular weight and film forming property Shenyang steel structure fireproof coating construction expert punde Building Fire Engineering Co., Ltd Recommended introduction: since its establishment, Shenyang punde Construction Fire Engineering Co., Ltd has cultivated a group of professional construction teams with excellent equipment, rich experience and serious responsibility with advanced and scientific management methods and strict engineering quality assurance and after-sales service system It has undertaken a number of fire system installation projects, which has been praised by customers Every idea and special requirement of you will be fully considered by us and fully realized in the construction technology, which will become the cornerstone of our successful long-term development We are looking forward to your invitation, to provide you with quality services and high-quality technical support! All construction coatings have passed ISO9001 Coatings home news: as silicone monomer and resin hydrolysis in water, it is difficult to prepare emulsion At present, there are three kinds of preparation methods of silicone acrylate emulsion (commonly known as silicone acrylic emulsion) (1) after polymer emulsification (physical method), organic resin or modified silicone resin is first prepared Water is used as dispersing medium and emulsifier is added to emulsify under the action of high shearing force This method can prepare stable emulsion only when the molecular weight is small Because of its small molecular weight and poor film forming performance, it can not meet the requirements of building coatings If the molecular weight is large, it is difficult to form stable emulsion In addition, in the ordinary emulsion mixing silicone emulsion, although it can solve the problem of stability, but it is only physical splicing, no chemical bonding, the performance is not very satisfactory (2) Polycondensation is mainly divided into two types One is the condensation of organosilicon monomer or resin with resin containing hydroxyl group and water-soluble monomer containing hydroxyl group in the presence of - fixed pH value and catalyst, hydrolysis or neutralization with water The resin can self emulsify in water without additional emulsifier Due to the stability of hydrolytic self emulsification and the tendency of water resistance after neutralization, it is also limited in practical application The second is to prepare hydroxyl based polymer emulsion, adding silicone emulsion in a certain range of catalyst and pH value, so that the hydroxyl group (-OH) and silicon hydroxyl (Si-OH) of the emulsion can be reacted and condensed, and the organic silicon can be introduced into the emulsion system Because of the use of catalysts, the stability and weatherability of the emulsion are all adversely affected (3) free radical emulsion polymerization is basically the same as that of conventional emulsion polymerization It is mainly composed of silicone monomers containing unsaturated bonds and various monomers containing unsaturated bonds, such as styrene, acrylates, tertiary vinyl carbonate and so on The purpose is to combine silicone resin with high temperature resistance, weather resistance, chemical resistance, hydrophobicity, low surface energy and low pollution, and the high color retention, flexibility and price of all kinds of monomer resins 。 The emulsion prepared by this method can prepare environment-friendly silicone acrylic emulsion paint with excellent water resistance, high weathering resistance, good antipollution and excellent ratio Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,