Abstract
The purpose of this study is to compare changes in structures of molecules of resin finished cellulosic fibers caused by thermal treatment with the thermal analytical observations., i. e., thermel degradation onset point, weight loss, end- and exothermal behavior and apparent activation energy.
Cotton and viscose rayon fabrics were treated with melamine (M), urea (U) and glyoxal (G) type resins respectively followed by heating with a programming rate of 10°C/min. The structual change to be brough about by thermal treatment was presumed by changes in characteristic absorption of infrared absorption spectra, that is, ratio of characteristic absorption (at 1700-1720 cm-1for carbonyl group to be produced by heating, at 1560 cm-1for M type resin, 1540cm-1for U type resin and 1700-1720 cm-1for G type resin) to the absorption at 2900 cm-1for streching vibration between C-H bond typical for the skeletal structure were regarded as measures for the structural changes. These ratios showed typical differences between kinds of resins as well as between cotton and viscose, that is, ratios of absorptions at 1560 cm-1and 1540 cm-1decreased with rise of temperature, while absorption at 1700 cm-1enhanced by increase in carbonyl group and reduction of absorption at 2900 cm. Comparison between changes in values of 1700 cm-1/2900 cm with elevating temperature and the above mentioned thermal analytical observations showed very good agreement in all cases. Thus, these thermal analytical behaviors well reflect in appearance of carbonyl group and its increase and structural change revealed by reduction of absorption at 2900 cm-1. It has been also shown by change in ratio at 1700 cm-1that in the case of cotton fabric treated with G type resin, structure of finished cellulosic fibers is largely dominated by cotton cellulose because of chemical bonding between resin monomer and cellulose molecules, while there is no interaction between resin and cellulose molecules in the case of viscose.
