High temperature ATR-FTIR characterization of the interaction of polycarboxylic acids and organotrialkoxysilanes with cellulosic material.

To convey novel properties to textile surface cotton-based fabrics were impregnated with solutions containing various chemical agents, such as butane-1,2,3,4-tetracarboxylic acid or hydrolyzed organotrialkoxysilanes (3-amino)propyltriethoxysilane), (3-glycidylpropyl)-trimethoxysilane, (3-triethoxysilylpropyl)succinic acid anhydride, octyltriethoxysilane, and Dynasylan F8815 (fluoroalkylfunctional water-borne oligosiloxane). The as-prepared cotton specimens were dried and cured at elevated temperatures. As the curing process can be performed at different temperatures, the impregnated and dried cotton samples were studied by means of time-dependent ATR-FTIR spectroscopy in an attempt to get a closer insight into the process mechanism. The results make evident that the butane-1,2,3,4-tetracarboxylic acid and (3-triethoxysilylpropyl)succinic acid anhydride reacts with the hydroxyl groups of the cellulose via a five-membered cyclic anhydride intermediate which is confirmed by vibration bands appearing at 1782 cm (symmetric stretching vibration of the anhydride carbonyl group) and at 1861 cm (antisymmetric stretching vibration of the anhydride carbonyl group).