Silicone emulsion is a form of silicone oil. The following is introduced from two aspects: silicone oil softener and silicone oil emulsion defoamer.














1、 Softening agent for silicone oil fabric


Silicone emulsion is mainly used as softener for silicone oil fabrics. The first generation of silicone fabric finishing agent is a mechanical mixture of dimethyl silicone oil and hydrogen silicone oil (and its derivatives). The second generation of organosilicon fabric finishing agent is hydroxyl terminated poly two methyl siloxane emulsion. It is made by emulsion polymerization of eight methyl ring four siloxane monomer, water, emulsifier, catalyst and other raw materials under certain conditions. Because polymerization and emulsification are completed in one step, it has the advantages of short working hours, high working efficiency, simple equipment and convenient operation. The emulsion obtained is very stable, and the particles are very uniform. The active polymer (hydroxyl) at both ends of the polymer can be further reacted to form a film, which is conducive to improving the application effect of emulsion, which is not enough for mechanical emulsified silicone oil.










Hydroxyl silicone oil emulsion can be divided into several types of emulsion, such as cation, anion, nonionic and compound ions, according to the different surfactants used.


















1. cationic hydroxyl silicone oil emulsion






The emulsifier used in cationic hydroxyl emulsion polymerization is quaternary ammonium salt (Octadecyltrimethylammonium chloride reported in Foreign Literature), and the catalyst is ammonium hydroxide. Cationic hydroxyl milk can be used in various textiles after finishing. It has the properties of improving fabric handle, improving fabric elasticity and smoothness. It has another unique advantage: the ideal waterproof agent for fabrics, it is compatible with methyl hydrogen silicone oil emulsion, waterproofing and waterproof durability. It can be used as waterproofing agent for polyester cover canvas and waterproof agent for polyester card cloth. And so on.










2. anionic hydroxyl silicone oil emulsion






The anionic hydroxyl milk is characterized by its compatibility in fabric finishing agent, and the emulsion is very stable. In particular, most of the auxiliaries in textile printing and dyeing are anionic. If cationic hydroxyl emulsion is used, it is easy to cause demulsification and bleaching oil. Anionic hydroxyl emulsion can avoid this disadvantage, so it is more popular with users and has a wide range of uses.










3. compound ionic hydroxyl silicone oil emulsion






Although cationic hydroxyapatite is an excellent fabric softener, this emulsion is not resistant to hard water, and can not be used in the same bath with dimethoxylated two hydroxyvinyl urea resin (2D) resin, catalyst magnesium chloride and anionic whitening agent. In addition, because of the poor stability of the emulsion, silicone polymers are easily separated from the emulsion and float on the liquid surface, commonly known as "bleaching oil". If the cationic and non-ionic emulsifiers are used in the emulsion polymerization, the shortcomings of the cationic emulsifier for preparing hydroxyl silicone oil emulsion can be overcome. The prepared silicone emulsion can withstand hard water, and can be used in the same bath with 2D resin, magnesium chloride and whitening agent VBL, and has good heat resistance and freezing resistance.










4. non ionic hydroxyl silicone oil emulsion






The non-ionic hydroxy milk has better adaptability and stability than the free hydroxy milk, so many countries are vigorously studying the non-ionic hydroxy milk. For example, UltrateX FSA, a new product made by the Swiss company, is a non-ionic emulsion with a molecular weight of more than 200 thousand and a hydroxyl head of two methyl siloxane. This is a step forward than the Dc-1111 anionic FSA milk of the US company.










5. Silicone finishing agent with other active groups






In order to meet the needs of advanced finishing of all kinds of fabrics, improve the anti oil, anti-static and hydrophilic properties of silicone finished fabrics, and make chemical fiber fabrics have many advantages of natural fabrics, silicone workers studied the introduction of other active groups on silicone molecules, such as amino group, amide group, ester group, cyano group, carboxyl group, epoxy group, etc. The introduction of these groups makes silicone fabric finishing agents have special effects. For example, the introduction of amino groups into silicone molecules is suitable for anti shrinking and softening finishing of wool fabrics; the introduction of amide groups is suitable for anti fouling finishing, and the softness is also greatly improved: the introduction of cyano groups has good oil resistance, and the copolymer of polyoxyethylene ether and silicone has good anti-static effect; the organofluorine modified silicone has oil repellency, anti-corrosion and anti-corrosion properties Anti pollution, anti-static, water repellent and many other advantages.