This type of softener is an emulsion or microemulsion of polysiloxane and its derivatives, which can make the fabric have a good soft and smooth feel. The products include emulsion polymerization, polymer silicone oil emulsification, modification, compounding and other production techniques, which have basically formed a system and supply more varieties and brands. However, the application effect and performance are still very different.
1. Dimethyl silicone emulsion:
This is the earliest product used in silicone softeners. The relative molecular mass of silicone oil used as a softener is generally 60,000-70,000. After finishing, it can give the fabric a slippery, firm and cool hand, reduce the friction coefficient of the fabric, and improve the abrasion resistance and seamability of the fabric. However, because there are no reactive groups on the molecular chain, it cannot react with the fiber or cross-link by itself, but only rely on molecules to attract and attach to the surface of the fiber, so the washing resistance is poor and the improvement in elasticity is limited.
2. Organic silicone hydroxy emulsion (hydroxy silicone oil emulsion)
This is the most widely used silicone softener in my country in the 1980s. Its relative molecular mass is generally 60,000-80,000. The larger the relative molecular mass, the better the softness and smoothness. Because of its molecular chain end and Hong group end-capped, under the action of crosslinking agent and catalyst, it can crosslink with the reactive base of the fiber or itself to form a certain elastic polymer film, so it is washable. , And can improve the elasticity of the fabric. According to the ionicity of the emulsifier used, organosilicone hydroxyemulsion is divided into cationic silicone hydroxyemulsion and anionic silicone hydroxyemulsion. Although the presence of hydroxyl groups at the end of the molecular chain of silicone hydroxyemulsion is helpful to improve its hydrophilicity and emulsion stability, it is difficult to control the fineness and uniformity of the emulsion particles of silicone hydroxyemulsion, so the stability of the emulsion is also very good. It is difficult to master, and it is easy to cause oil bleaching during application, which makes it difficult to remove oil spots and other defects on the fabric. Therefore, the emulsion stability of the silicone hydroxyemulsion softener is also an important indicator for evaluating its quality.
3. Hydrophilic soluble silicone (polyether hydrophilic silicone)
This kind of silicone softener is usually polyether and epoxy modified polysiloxane. The appearance is a colorless and transparent thick liquid, which can give the fabric good moisture absorption and air permeability and antistatic properties. Ionic, can be mixed with various additives. When it is used together with resin, it can reduce the resin's chlorine absorption and release formaldehyde; in addition to resin finishing and soft finishing, it is also widely used in paint dyeing process, which can not only improve the feel of fabrics affected by adhesives, The shortcomings of the adhesive roller can also be improved.
4. Amino modified silicone
The introduction of amino groups into the macromolecular chain of polysiloxane can greatly improve the performance of organosilicon. The introduction of amino groups can not only form firm orientation and adsorption with fibers, reduce the friction coefficient between fibers, but also chemically react with epoxy groups, carboxyl groups, and hydroxyl groups, so it can be applied to cotton, wool, silk, and viscose. Fiber, polyester, nylon, acrylic and other fibers and their blended fabrics. After finishing the fabric, it can obtain excellent softness and resilience, and its hand feel is soft and plump, smooth and delicate. Generally speaking, the higher the amino content, the better the softness. But higher amino content also means greater yellowing.