Effect of Solvent Induced Hydroxylation of Cyanoethyl Group on Dye Uptake of Cotton Fabrics A. Selva Subha, S. Thambidurai Department of Industrial Chemistry, Alagappa University, Karaikudi 630 003, Tamil Nadu, India Received 7 February 2006; accepted 23 August 2006 DOI 10.1002/app.25784 Published online 23 January 2008 in Wiley InterScience (www.interscience.wiley.com). ABSTRACT: The present investigation deals with the dyeing behavior of solvent induced cyanoethylated cotton fabric. The modified cotton fabric was dyed by conven- tional method with commercial reactive dye (Drimarene Red). It is observed that acetone induced cyanoethylated samples exhibit higher color values than ethanol treated samples. The effect of nitrogen content on the dye uptake of modified fabric is assessed which shows a good correla- tion between them. It is obvious that crystallinity has a no- ticeable effect on the dye uptake of both solvent modified fabrics. For convenience and comparison, a set of samples are also dyed without addition of salt, alkali, and both. It is evident that even without addition of salt, alkali and both the samples exhibit a significant dye uptake. Ó 2008 Wiley Periodicals, Inc. J Appl Polym Sci 108: 1373–1377, 2008 Key words: cyanoethylation; reactive dye; dyeability; color strength INTRODUCTION With an aim of imparting new properties chemical modification of cellulose has been extensively studied. Previous studies have revealed that chemically modi- fied cotton cellulose exhibits different behavior towards dyeing compared with that of unmodified cellulose. Hilw and Hebeish 1 investigated the effect of nature of the substituents of the modified cotton fab- ric on the susceptibility towards different dye stuffs. Reactive dyes are most commonly employed be- cause of their good color value and reasonably high fastness properties. It has been reported 2–7 that the cotton fabric is treated with various chemicals prior to dyeing to improve its dyeability with reactive dyes and to facilitate dyeing at neutral pH. 8,9 In our earlier study 10 we have dealt with the effect of solvent-induced partial cyanoethylation and hydro- xylation of cyanoethyl group on the physio-chemical properties of cotton fabric and found that hydroxyla- tion of cyanoethyl group results in formation of amide group. Recently Bhattacharya and Agarwal 11 have reported the amide group formation on cellulose struc- ture after polyacrylamide-hydrazine treatment on cotton and feasibility of neutral dyeing with reactive dyes. Keeping this in mind, the present work aims to investigate the dyeability of solvent induced partially cyanoethylated cotton fabric using reactive dye and also the effect of solvent induced hydroxylation of cyanoethyl group on the dyeing behavior of cotton fabrics at neutral pH condition. EXPERIMENTAL Materials and methods Scoured plain weave cotton fabric (Area: 30 Â 24 cm 2 ; Ends/in.: 140; Picks/in.: 80, Count: 40 s, Weight/sq. cm-0.015 g) was used throughout the study. All the chemicals used were laboratory grade. Surgical spirit was used for ethanol treatment. The dye sample (Drimarene Red HE3B) was supplied by Clariant dye manufactures. Partial cyanoethylation The solvent induced cyanoethylation using acetone and ethanol was carried out as described earlier. 10 The mercerised and acetone, ethanol induced modi- fied cotton fabrics were dyed with Drimarene Red HE3B according to the conventional method using NaCl (30 gpl), sodium carbonate (15 gpl), 2% shade, and 1: 20 liquor ratio. Dyeing temperature was raised from 40–808C after which the dyeing was car- ried out for further 45 min. The dyed samples were taken out, washed with cold water, soaped at boil, rinsed thoroughly in hot water, washed again with cold water, and finally air-dried. The same method of dyeing was repeated without adding either salt or alkali and both. Mercerised sample was taken as control sample. Correspondence to: S. Thambidurai (sthambi01@yahoo. co.in). Journal of Applied Polymer Science, Vol. 108, 1373–1377 (2008) V V C 2008 Wiley Periodicals, Inc.