Studies on the Chlorine Retention of Fabrics Treated with Dimethylol Ethylene Urea

Abstract

Chlorine retention and loss in strength due to scorching have been reported for fabrics treated with dimethylol ethylene urea DMEU) under different conditions of processing and use. Since DMEU is theoretically not expected to be chlorine retentive, various mechanisms have been proposed in the literature to explain this anomaly. The present paper reports the results of studies designed to follow the chemical changes produced in DMEU under different conditions of treatment and to relate these to chlorine retention and damage. It has been shown that DMKU-treated fabrics contain varying amounts of >NH, >NCH₂OH and > NCH ₂OCH₂N< groups under different conditions of treatment. All these groups lead to chlorine retention. The molar ratio of formalde hyde to cyclic ethylene urea (CEU) in the DMEU, the efficiency of the catalyst in promoting cross-linking with cellulose, the possibility of hydrolysis of the cross-links during storage or laundering, etc., are all factors affecting chlorine retention. Even under optimum conditions of processing and storage. changes are produced in the finish which increase considerably the damage due to chlorine retention, particularly when such a fabric is given repeated alkaline washings.