engleski

Interface Phenomena of Modified Cotton Materials

The most important phase in textile finishing processes is adsorption of chemical substances and compounds on textile materials surface and wettability as well. Interface phenomena happen between liquid and solid phase, like water solution and textile material, resulting in change of textile material surface free energy. Electrokinetic phenomena, as zeta potential and specific amount of surface charge, characterize electric charge of textile material, while contact angle characterize its wettability. This paper deals with interface phenomena of pretreated and modified cotton materials. For this purpose damask cotton fabric was desized, enzymatically and alkali scoured, bleached and mercerized in industrial conditions. Modification of cotton fabric for achieving electropositive charge was carried out by cationization during mercerization with cationic compound, quaternary ammonium salt. It is an alternative method for improving dyestuff and surfactant adsorption. Additionally, the influence of cotton pretreatments on its mechanical properties has been investigated. The effect of modification on the change of fabric zeta potential, surface free energy, contact angle, and specific amount of surface charge were discussed. The zeta potential was measured by streaming current method on Electrokinetic analyzer, EKA depending on pH and surfactant addition. Isoelectric point, IEP and Point of Zero Charge, PZC were calculated from the results of zeta potential measurement. Contact angle was measured on DataPhysics OCA 20 Instrument using three different liquids – water, formamide and diiodomethane. From the results of disperse and polar components surface free energy was calculated. According to Chibowski method, wicking distance of polar and apolar solvents – water, formamide and n-heptane, components of surface free energy were calculated. The surface free energy calculated by different methods were discussed in a quantitative way.

Cotton Fabric; Interface Phenomena; Zeta Potential; Surface Charge; Surface Free energy; Contact Angle

nije evidentirano