Fibre surface modification by sol-gel finishes with inorganic oxide films

4 Fibre surface modification by sol-gel finishes with inorganic oxide films 

For many applications, especially technical applications, textiles should be protected against physical or chemical assault, for example abrasion, damage by UV radiation and aggressive chemicals. This can be achieved by thin crosslinked layers of inorganic or mixed inorganic-organic polymers on the fibre surface These special finishes are carried out with common techniques at moderate processing temperatures that do not exceed 150 °C and result in very thin polymer films on the fibre surface. 

Another advantage of the silicon oxide network is that it can be modified in various ways as shown in Fig. 18.2. One way is co-condensation of the most nsed tetramethylol silanes with other kinds of metal oxides. Another way is cohydrolysis and co-polycondensation with snbstitnted trimethoxy silanes where this substituent is, for example, a long alkyl chain for hydrophobation, an organic portion with polar structures for antistatic effects, a fluorocarbon for the release of water, oil and soil or a bioactive group. The easiest method of modification is the physical one, the simple addition of the desired chemicals. They are then incorporated in the porous network of the metal oxides and are released in a more or less controlled way. 

2 Schematic representation of the chemical modifications of the silicon oxide network. Inorganic modification with M = Al, Ti, Zr and others, organic modification with R = alkyl, aryl, both without and with additional functional groups, for example fluoroalkyl, or R = bioactive or dyestuff group. 

Principles of storage, fixation and release Advantages and disadvantages 

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