Harsh handle

Polysiloxanes as shrink-resist finishes have been developed from their traditional uses as softeners and water repellents as such their chemistry is discussed in section 10.10.3. This was a natural trend as many shrink-resist finishes tend to impart a harsh handle to wool. 

In contrast to TEXAPRET A, TEXAPRET AM contains reactive groups. It produces a full, slightly stiff, but not harsh, handle, and can be fixed with resistance to washing by using N-methylol compounds. 

Plasma treated wool may exhibit more or less firm or harsh handle because of surface roughening. This property is very important for hand-knitting yams or yams for underwear fabrics. Softeners generally deteriorate the shrink resistance imparted by plasma treatment or plasma plus polymer after-treatment quite heavily [36]. The enzyme treatment is capable of improving the handle of plasma treated wool as well as plasma treated and polymer after-treated hand-knitting yams without imparting their shrink resistance [62]. 

Wool can be bleached with sodium hydrosulphite or its derivatives, but in practice they do not find much application, partly because they tend to impart a harsh handle. They are used as stripping agents to remove dyes when this is necessary. 

Nevertheless, there are some problems correlated with the use of this support, such as its voluminous nature when swollen, its lack of physical stability im-der harsh handling conditions, and its incompatibility with a number of solvents (8). For this reason, several groups of researchers have investigated a number of alternative solid supports, for solid-phase chemistry, in order to improve resin properties, such as physical robustness, ease of handling, enhancement in loading,... 

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