Fluorinated Compounds applied to Cotton Fabrics via Sol-gel

The sol–gel technique has been reported as a promising tool for preparation of water repellent coatings especially versatile for application on textile or wood. In the present work, hydro and oil repellency were conferred to cotton fabrics by an hybrid organic-inorganic finishing via sol-gel. The nanosol was prepared by co-hydrolysis and condensation of tetraethoxysilane (TEOS) and 1H,1H,2H,2H–fluorooctyltriethoxysilane (FOS) or Fluorolink S10, a lower cost commercial fluorosilane product, as precursors. The application on cotton was carried out by padding, followed by drying and thermal treatment, varying the weight on from 5 till 30% o.w.f. Treated samples were tested in terms of contact angles measured with both water and oil, drop adsorption times and washing fastness, and characterized by SEM, ATR and XPS analysis. Good results in terms of conferred properties were obtained in all the investigated cases but, considering the treatment fastness, best results were related to Fluorolink S10 nanosol. Moreover, a comparison with a conventional thermal finishing product was carried out, showing the sol-gel as a promising alternative process.