Since the main chain of silicone softener is -Si-O-, which is longer than -C-O-, the molecular chain is softer and has excellent lubricating and soft properties. It has been widely used in textile finishing. Its development process has gone through the following four stages.
The first generation of silicone softeners started in the 1950s and 1960s. Representative products include dimethyl polysiloxane (PDMS) and hydroxy silicone oil emulsion. The first-generation product has the advantages of low cost, reduced color of the fabric after treatment, and very lubricating. However, because of the lack of reactive functional groups, it has poor washing resistance, softness of the hand and poor rebound effect, and the emulsion will be unstable and stratified, resulting in the generation of silicone oil spots. At present, the first-generation products are rarely used as fabric softeners, and are generally used as yarn lubricants, filler fiber treatment agents or chemical fiber spinning finishes.
Due to the single function of the first-generation silicone softener, it is very easy to demulsify and bleach the oil during use. Since the 1980s, silicone workers have developed the second-generation silicone softener, which is a modified organic Silicone softener. This type of product is through the introduction of amino groups, epoxy groups on the side chains of the siloxane or emulsion polymerization. The second-generation product greatly improves the washing durability of the fabric, and relies on different groups to give the fabric different styles.
Amino-modified silicone oil has a smooth feel and rebound effect, good washing resistance, and can improve the tearing strength of fabrics. It can be used in the same bath with resin. However, it also has the disadvantages of instability and delamination of the emulsion, leading to the generation of silicone oil spots. Generally, the water-absorbent fabric is not hydrophilic after finishing, and has the disadvantages of large yellowing and color change. Amino modified silicone oil is currently the most used modified silicone fabric softener on the market. Epoxy-modified silicone oil feels dry and has a rebound effect. After treatment, the yellowing of the fabric is very small, which can improve the tearing strength of the fabric. It can be bathed with the resin. However, after finishing the fabric lacks fullness and softness, the emulsion will be unstable and delamination, which will cause the generation of silicone oil spots. Generally, the water-absorbent fabric will not be hydrophilic after finishing. Generally used in water-repellent soft finishing. In the production process of emulsion polymerization silicone oil, polymerization and emulsification are carried out at the same time, the production cost is low, the emulsion particles are larger, and the smoothness is very good. The main disadvantage is that the softness of the hand is not good, and there will be a small amount of precipitate during the storage of the product. Mainly used in the smooth feeling treatment of various fiber fabrics.
In the 1990s, developers introduced polyether active groups on the side chains of siloxanes to improve the hydrophilic properties of the fabrics after finishing with the third-generation silicone softeners, which means that the products are modified by polyethers. Silicone oil and amino (epoxy)/polyether modified silicone oil. The pure polyether modified silicone oil can provide instant water absorption function, has water dispersible/water soluble characteristics, the fabric has no yellowing and color change after treatment, no emulsification, no delamination and oil spots, and the fabric can be re-dyed after treatment. Reprint.
However, the finished fabric has poor smoothness, no plump and soft feeling, and the hydrophilicity and softness are not durable, and the tearing strength of the fabric is not improved. This type of product is only suitable for those that need instantaneous water absorption and require general soft finishing. Compared with monopolyether modified silicone oil, amino (epoxy)/polyether modified silicone oil has better hand feeling than monopolyether modified silicone oil and slightly higher yellowing. It is mainly used as a general-purpose hydrophilic soft finishing for general fabrics agent.
Around 2000, foreign silicone workers developed the fourth generation of silicone softeners-linear block multi-copolymerization modified silicone softeners. The fourth-generation product integrates the advantages of the first three-generation products and avoids the problems of the first three-generation products. It is a new silicone softener product with excellent comprehensive performance.
This silicone softener has a wide range of applications and can be used in various fibers and fabrics; it is convenient and simple to use, and it is very easy to disperse in water. It basically does not use emulsifiers or uses a small amount of emulsifiers. High-concentration products can be used directly; the compatibility is very good , Has excellent stability to strong acids, strong bases, high electrolytes, etc.; very good high temperature and high shear stability, and extremely high adaptability and flexibility to processes and equipment.
Silicone softener uses no layering, demulsification, no oil spots, no sticking to rollers, no sticking to cylinders; very low yellowing and discoloration; good washing resistance; full and fluffy, elastic, smooth, and silky texture It has a "natural" comfort feeling, which overcomes the shortcomings of traditional amino silicone oil that is too "greasy"; it has a very good feel and can be super soft; it has medium or higher hydrophilicity, which can be the same as organic fluorine easy decontamination and finishing. Use; color repairable, peelable, re-dyeing and over-dyeing, no secondary pollution; basically does not affect the heat migration fastness of disperse dyes on polyester, and maintains the color fastness to washing and rubbing before soft finishing.