Carboxymethylated cotton fiber

Mizutani C, Onogi Y, Inagaki H, Sato T. and Miyamoto T., Water absorbency of lightly carboxymethylated cotton fibers, Sen-I-Gakkaishi, Vol48, 1992, p. 677. 

Cellulose, obtained from wood pulp or cotton fibers, is carboxymethylated, followed by conversion to the calcium salt. It is then graded on the basis of its degree of carboxymethylation and pulverized. 

The Ci, Cx concept has recently been extensively studied by a number of workers (16,23, 24, 27, 31, 32,46), for two species of Trichoderma, namely T. viride and T. koningi. It was shown that cell-free culture solutions of these fungi were able to solubilize cotton fibers. The solubilization of cotton fibers is also a way of measuring the activity of the Ci enzyme. In the most recent of these publications (46) Selby and Maitland were able to isolate the Ci enzyme from culture filtrates of T. viride. The enzyme was shown not to act upon cellobiose or carboxymethyl cellulose and to lose its ability to solubilize cotton in the absence of the Cx component. The mechanism of action of the Ci enzyme is thus still obscure although many different hypotheses have been presented (34). 

Cellulosic fibers such as cotton and viscose rayon can be treated with chloroacetic acid to make highly absorbent carboxymethyl cellulose fibers. When partially car-boxymethylated, the carboxylic acid groups in the fibers are able to absorb a large amount of water into the fiber structure, hence the treated fibers are capable of a high degree of swelling when wet in water. 

Figure 6 Percent levels of dicarbonyls in dialdehyde cotton gauze (DAG I and II) and carboxylates (CMC III and TV) on carboxymethylated cellulose as determined by titration on modified cotton fibers. Data are mean SE of triplicate determinations.

In carboxymethylation of cotton, the fibers are impregnated with aqueous sodium hydroxide and then treated with chloroacetic add ... 

The carboxymethyl cellulose (CMC) derivatives and carboxymethyl starch (CMS) are effective antiredeposition agents that are cellulose-containing fibers such as cotton and blends of cotton and synthetic fibers. However, CMC has virtually no effect on pure synthetic fibers. Other effective antiredeposition agents and soil repellents have been developed (Fig. 5.4) [20]. 

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