Efficient immobilization of montmorillonite onto cotton textiles through their functionalization with organosilanes

The production of functional cotton textiles through their derivatization with montmorillonite (Mt) is reported. The K10 montmorillonite (K10) was functionalized with the organosilanes (3-bromopropyl)trimethoxysilane (BrPTMS), (pentafluorophenyl)trimethoxysilane (F5PTMS) and (3-isocyanatopropyl)triethoxysilane (NCPTES) by a post-grafting methodology.Subsequently, these materials were immobilized onto NaOH-activated cotton textile substrates through a dyeing-like process typically used in the industry. The silylated clay minerals were characterized by Fourier Transform Infrared Spectroscopy-Attenuated Total Reflectance (FTIR-ATR), thermogravimetry (TGA), powder X-ray diffraction (XRD), scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDX), which confirmed their successful functionalization. The Mt-functionalized cotton textiles were characterized by X-ray photoelectron spectroscopy (XPS), SEM-EDX and TGA before and after washing tests.The previous activation of the cotton textile with NaOH promoted a more efficient immobilization of the clay minerals, whereas the addition of a common surfactant used in the dyeing industry did not exhibit any influence on the dispersion of the Mt materials in the textile substrates. The functional textiles submitted to ten washing cycles did not present significant Mt leaching, confirming the efficient immobilization of the mineral particles onto the textile substrates. The best results in terms of immobilization efficiency were obtained for the textile substrate functionalized with the BrPTMS-modified K10.