Uporaba tenziometrije za zasledovanje sorpcijskih lastnosti celuloznih vlaken

The improvement of wettability and sorptivity is a major task during textile finishing. In order to create the proper sorption character of regenerated cellulose fibres different pre-treatment processes are applied such as washing and bleaching. Classical viscose, modal and a new type of regenerated cellulose fibres called lyocell, have the same chemical structure, but a different molecular and supramolecular structure. The differences in the sorption properties of untreated and pre-treated regenerated cellulose fibres were obtained using a new alternative method-tensiometry and compared with various methods for determining water adsorption. Tensiometry is an analysing method for measuring the surface tensions, contact angles and adsorption. We measured the sorption abilities using the Powder Contact Angle Method and as a result we get a capillar velocity. From the velocity we can calculate the contact angle between the solid - fibres and the liquid - water/heptan. The pre-treatment increases the adsorption abilities and makes the material more accessible to chemicals used in finishing processes. The raw viscose fibres show the highest amount of moisture and have the lowest contact angle (φ 68,3°), raw modal fibres have the biggest contact angle (φ 77,1°). Using chemical bleaching we improve the sorption abilities. The bleached viscose fibres have the lowest contact angle (φ 57,8°).