Changes of Physical Properties of Cellulose Fibres by the Impact of Ultrasound

Abstract

The impact of 30 kHz frequency ultrasound waves, on cellulose fibres is investigated, after a thirty-minute treatment in an aqueous medium at room temperature. The impact of ultrasound treatment on property modification of cotton, viscose and lyocell fibres has been determined by investigating dimensional, morphological and mechanical properties of the fibres before and after the ultrasound treatment. The results obtained show that ultrasound treatment yields some changes in the properties investigated. Certain amount of fibre shrinkage and higher mass per unit length for all the samples has been confirmed without any doubt. Cotton fibres exhibit lower number of curls, while curliness increases with man-made cellulose fibres. Curl contraction determination indicates that the curls gain on intensity after ultrasound treatment with viscose fibres, while modest weaviness can be seen with lyocell fibres. Fibre strength has been determined employing the method of individual measurements and the results obtained indicate that ultrasound treatment yields higher breaking strength for all the samples tested, with the same trend being noticeable when measuring breaking elongation with almost all the samples tested. As opposed to quite clear and uniform results obtained by measuring individual fibres, when fibre bundles are tested the values are somewhat reduced for individual samples.