Cotton mercerization

Cotton Mercerizing and Scouring. An estimated 1.7% of caustic soda consumption goes into cotton mercerizing and scouring. The majority is used for mercerizing and demand is expected to decline between 2.5 and 5%/yr (6). 

Technique Cotton Mercerized cotton Wood pulps Regenerated cellulose... 

Mercerized Cellulose (Mercerized Cotton). Mercerization is a process of treating cotton with 25% Na hydroxide which causes it to shrink and become heavier, stronger, denser, and acquire a milky luster it will not shrink and is more easily dyed. It is more active and easier to nitrate than the original cellulose, but the resulting prod is not very stable Refs 1) Hackh s (1944), 523 2) Doree... 

Mercerizing Liquors.—Quantities of liquor will vary considerably with the process of washing used in each plant, and a reasonable average will give 2 gal. of 6°Twaddell waste liquor for each pound of cotton mercerized. These liquors are usually concentrated to from 70 to 80 Twaddell in a triple- or quadruple-effect evaporator of the horizontal-tube or rapid-circulation type. The capacity is from 2H to 3H gal. per square foot, with a steam pressure of from 10 to 15 lb. Special construction and entrainment separators are necessary to prevent losses by foaming. The last effect will frequently show incrustations of sodium carbonate which can be dissolved in hot water or weak hquor. Evaporators are usually built of steel with steel or charcoal-iron tubes. 

Appearance of Fibers.—Examine under a microscope a fiber of each of the following Silk, wool, cotton, mercerized cotton, and linen. 

Technique Cotton Mercerized Cotton Wood Pulp Regenerated Cellulose... 

The influence of polyethylene morphology on its reactivity has been analyzed in Section 1.3.4.1 this section will be limited to the case of cellulose, which has been the subject of many studies. It has long been known that the reactivity of cellulose depends on its morphology. Thus, when cotton is etherified by diazomethane the extent of conversion of hydroxy group (molar %) is 7.0,14.9,18.6,5.9 and 20.6 for native cotton, mercerized cotton, cupro rayon, hydrocellulose and finely ground cotton respectively it is obvious that these values vary with the accessibility of the material. 

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