Softening finishes mechanisms

Reactive softeners Some softeners have functional groups that can react with the corresponding groups of some fibres, for example A-methylolated amines with the hydroxyl groups of cellulose (compare the mechanism of the crease resistance finish). The result is a very durable finish, combined with the typical advantages and disadvantages of this crosslinking chemistry, as discussed in Chapter 5. 

The removal of cellulosic fibres to improve pilling performance, soften hand, and create an abraded appearance requires not only enzymatic hydrolysis but also mechanical action to carry away reaction by-products physically. The final results from the hydrolysis with respect to appearance and hand are affected just as much by the mechanical components of the process as by the chemical components. Therefore, laboratory evaluations of bio-finished goods can only produce relative rather than absolute results. 

SOFTENER 27-3 is a nonionic polyethylene emulsion designed for use in textile finishing to provide durable softness and lubricity. The polyethylene in SOFTENER 27-3 is of the medium to high density type. The product has been formulated to provide exceptional emulsion stability over a wide range of pH, temperature and mechanical shear conditions. 

Polymeric blend. Softener and napping assistant for cotton and cotton/polyester blends. Improves fabrics mechanical properties such as sewability and is non-yellowing and non-chlorine retentive. May be used in thermosetting resin finishes. 

In many instances silicone softening agents are also used in durable press finish formulations in combination with crease-resistant resins and than are distinguished by a substantial improvement in the mechanical properties of the textiles in addition to the softer handle. 

Fabric softeners remedy these degradations and improve the feel by coating the fibers with a protective film of fatty material that reconstitutes the finish, maintains the microfibrils close to the fibers [23], masks fiber alterations, and covers the mineral deposits. Hence, the main mechanism for fabric softening is fiber lubrication. 

The principal rheological aspect of thermoforming is the stretching of the softened polymer sheet. As such, the material is subjected to orientation. Such orientation can affect the mechanical behavior of the finished product. 

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