Mercerization, effect

An important chemical finishing process for cotton fabrics is that of mercerization, which improves strength, luster, and dye receptivity. Mercerization iavolves brief exposure of the fabric under tension to concentrated (20—25 wt %) NaOH solution (14). In this treatment, the cotton fibers become more circular ia cross-section and smoother ia surface appearance, which iacreases their luster. At the molecular level, mercerization causes a decrease ia the degree of crystallinity and a transformation of the cellulose crystal form. These fine stmctural changes iacrease the moisture and dye absorption properties of the fiber. Biopolishing is a relatively new treatment of cotton fabrics, involving ceUulase enzymes, to produce special surface effects (15). 

Nature of the metal surface The critical concentration of an anion required to inhibit the corrosion of iron may increase with increasing surface roughness. Thus, Brasher and Mercer" showed that the minimum concentration of benzoate required to protect a grit-blasted steel surface was about 100 times greater than that required to protect an abraded surface. However, surface preparation had little effect on the critical inhibitive concentrations for chromate" or nitrite " The time of exposure of the iron surface to air after preparation and before immersion may also affect the ease of inhibition by anions. There is evidence """ that the inhibition by anions occurs more readily as the time of pre-exposure to air increases. Similarly, if an iron specimen is immersed for some time in a protective solution of an inhibitive anion, it may then be transferred without loss of inhibition to a solution of the anion containing much less than the critical inhibitive concentration . ... 

Later their use in the pretreatment of cotton was described, i.e., mercerizing [169], boiling off [8,170], and bleaching [170,171], For wool washing and wool treatment ether carboxylates have also been mentioned the detergent effect is better than that of the corresponding nonionics, a pleasant feeling is achieved and there is no corrosion on metal [172],... 

Mercer, T.T., The Effects of Particle Size on the Escape of Recoiling the RaB Atoms from Particulate Surfaces, Health Physics 31 173-175 (1976). 

Kagan VE, Tyurina YY, Tyurin VA, Konduru NV, Potapovich AI, Osipov AN, Kisin ER, Schwegler-Berry D, Mercer R, Castranova V, Shvedova AA (2006) Direct and indirect effects of single walled carbon nanotubes on RAW 264.7 macrophages Role of iron. Toxicol. Lett. 165 88-100. 

Firestone, P., Monteiro-Musten, L., Pisterman, S., Mercer, J., and Bennett, S. (1998) Short-term side effects of stimulant medication are increased in preschool children with attention-deficit/hyper-activity disorder a double-blind placebo-controlled study. / Child Adolesc Psychopharmacol 8 13—25. 

The center manifold approach of Mercer and Roberts (see the article Mercer and Roberts, 1990 and the subsequent article by Rosencrans, 1997) allowed to calculate approximations at any order for the original Taylor s model. Even if the error estimate was not obtained, it gives a very plausible argument for the validity of the effective model. This approach was applied to reactive flows in the article by Balakotaiah and Chang (1995). A number of effective models for different Damkohler numbers were obtained. Some generalizations to reactive flows through porous media are in Mauri (1991) and the preliminary results on their mathematical justification are in Allaire and Raphael (2007). 

Mercer et al. have studied the effect of moisture in fluorinated polyimides extensively. Beuhler et al. have also studied moisture absorption in fluorinated polyimides and have shown that moisture absorption decreases with fluorine incorporation, even as free volume increases (see Table 13.6). 

A much more extensive investigation of the effect of alkalies has been made in the case of polysaccharides, especially cellulose this is understandable in view of the industrial importance of mercerization, of the viscose process, and of cellulose ethers. Various complexes have been reported for cellulose and alkalies depending upon the nature of the alkali, upon its concentration, upon the washing treatment used, and upon the pretreatment of the cellulose. A discussion of this subject has been published by Nicoll and Conaway.84 There is general agreement on the formation of several compounds, which are susceptible to hydrolysis. The question as to whether these compounds are molecular complexes (XLVII), true alkoxides (XLVIII), or an equilibrium mixture of the two has not been answered. In recent studies Lauer65 has reached... 

The dyer must also consider the effect of the substrate. Substantivities for mercerized cotton and regenerated celluloses are higher than those for unmercerized cotton. 

Mercer, T.T. (1976) The effect of particle size on the escape of recoiling RaB atoms from particulate surfaces. Health Physics, 31, 173-5. 

Ellis, F.B., Mercer, E.R. Milbourn, G.M. (1968) The contamination of grassland with radioactive strontium - II Effect of lime and cultivation on the levels of strontium-90 in herbage. Radiation Botany, 8, 269-84. 

Mercer, K.L. and Tobiason, J.E. 2008. Removal of arsenic from high ionic strength solutions Effects of ionic strength, pH, and preformed versus in situ formed HFO. Environmental Science and Technology, 42 3797-802. 

---