Chemical modification of cotton with the aim of making it better than in its natural state so as to counter the intensive competition of synthetic fibers has been extensively studied. This subject has been recently reviewed.' However, to our knowledge, not much work has yet been published on making use of chemical modification of cotton prior to durable-press finishing so as to deal with one of the most serious problems associated with such type of finishing, namely the greater susceptibility of easy-care cottons to soiling and their lower levels of soil r e r n ~v a l . * ~~
The present work was undertaken with a view of studying the effect of introducing carboxymethyl, cyanoethyl, and cyanoethyl together with carboxyethyl groups in cotton cellulose prior to durablepress finishing on the soil-release properties of easy-care cotton.
Partially carboxymethylated cotton (PCMC) was prepared4 by padding the cotton fabric (bleached poplin) in an aqueous solution of monochloroacetic acid (4N), followed by padding with sodium hydroxide solution (lON), and then storing in a polyethylene cover a t ambient conditions for 16 hr. At the end of this procedure, the fabric was thoroughly washed, neutralized with HCl (l%), washed again, and finally dried a t room temperature. A control sample was prepared under similar conditions, but treatment with monochloroacetic acid was omitted.
Cyanoethylated cotton (CEC) was prepared according to a method described elsewhere5 by impregnating the fabric in an aqueous solution of sodium hydroxide (570, w/v) for 15 min followed by squeezing to ca. 100% wet pickup. After being batched for 10 min the alkali-treated fabric was treated with acrylonitrile and stored in a polyethylene cover for 18 hr. The fabric was then washed and dried as above. A control sample for this modified cotton was prepared under similar conditions, except that no treatment with acrylonitrile was carried out.
Cotton bearing cyanoethyl along with carboxyethyl groups (HCEC) was obtained by partial hydrolysis of cyanoethylated cotton. The latter was padded with aqueous sodium hydroxide (10%) to a wet pickup of ca. 100%, followed by storing a t room temperature for 8 hr. The fabric was then washed and dried as usual.
Easy-care finishing was performed by padding the fabric in a solution containing 120 g/l. dimethyloldihydroxyethylene urea (DMDEU) and 18 g/l. magnesium chloride hexahydrate to a wet pickup of ca. 8O%. The fabric was then dried a t 100°C for 5 min, cured at 160°C for 3 min, thoroughly washed, and finally dried a t ambient conditions.
The carboxyl content of the said modified cottons was determined according to a reported method: nitrogen content by the Kjeldahl method, and moisture regain by a standard method. Evaluation of soil-release properties (the release of oily soil) was carried out as per Kissa's method.7 Conditioned crease recovery was monitored using Wrinkle Recovery Tester, T. J. Edwards Inc., Boston, and tensile