Hydroxy ethylcellulose

Reaction with an epoxide such as ethylene oxide under alkaline conditions gives hydroxy-ethylcellulose (HEC). 

Figure 10. Degree of grafting for cellulose and cellulose derivatives initiated by UV light of > 254 nm. Key a, fibrous carboxymethylcellulose b, ethylcellulose c, methylcellulose d, cellulose e, powdered carboxymethylcellulose f, hydroxy-ethylcellulose g, acetylcellulose.

Wirick MG. Study of the enzymic degradation of CMC and other cellulose ethers. / Polym Sci 1968 6(Part A-1) 1965-1974. Anonymous. Final report on the safety assessment of hydroxy-ethylcellulose, hydroxypropylcellulose, methylcellulose, hydroxypropyl methylcellulose and cellulose gum. / Am Coll Toxicol 1986 5(3) 1-60. 

Anonymous. Final report on the safety assessment of hydroxy-ethylcellulose, hydroxypropylcellulose, methylcellulose, hydroxypropyl methylcellulose and cellulose gam. Am Coll Toxicol 1986 5(3) 1-60. 

Replaceable Gels (entangled polymer networks) linear polyacrylamide, methyl cellulose, hydroxypropylmethyl cellulose, hydroxy-ethylcellulose, polyethylene oxide, polyvinyl alcohol, agarose... 

Dahl, T., He, G-X., and G. Samuels. 1998. Effect of hydrogen peroxide on the viscosity of a hydroxy-ethylcellulose-based gel. Pharm. Res. 15 1137-1140. 

Resin Solubilizers. In general, water-soluble resins are amine salts of acidic polymers. Water-soluble coatings formulated with AMP-95 and DMAMP-80 exhibit superior performance (15,16) (see WATER-soLUBm polymers). AMP-95, used in conjunction with associative thickeners (17) or hydroxy-ethylcellulose, provides for the most efficient utilization of such thickeners. It also is the neutralizer of choice for use with hair spray resins. 

Figure 7.1 Chromatograms of non-ionic polymers A, pullulan B, methylcellulose C, hydroxy-ethylcellulose D, polyvinyl alcohol E, polyacrylamide, obtained on TSKgel GMPW (two 600 X 7.5 mm I.D. columns) with 0.1 M sodium nitrate at a flow rate of 1 mL min " and 25°C [15].

Hydroxy-ethylcellulose + poly (ethylene oxide) Poly(ethylene oxide) + sodium alginate + chitosan Poly(glycidol-co-ethyl glycidyl carbamate... 

It is known in the literature that some enzymes can catalyze the acylation reaction of polysaccharides (9,10). Not surprisingly, lipases can serve this function (9) because lipases are known to mediate ester hydrolysis or synthesis. Yet, some proteases can also catalyze this reaction (10). For example, Alcalase protease immobilized on Celite can transfer the acrylic group onto hydroxy-ethylcellulose (HEC) to form an ester(9a) (Figure 2). Thus, in this case Alcalase appears to have broad substrate specificity and can work well with esters. 

Methyl and ethyl ethers of cellulose with a degree of substitution (D.S.) of 0.1 to 0.35 are used as emulsifying agents and paper sizes. Hydroxy-ethylcellulose (D.S., 0.5) is also used as a size. Highly substituted ethyl-celluloses (D.S., 2.2 to 2.6) are of great importance in the plastics, film, and lacquer industries. Carboxymethylcellulose (D.S., 0.5 to 0.75) is used as a thickener in foods, and the sodium salt is added to washing powders in which its action in laundering is to prevent redeposition of soil in the fabric. 

A mixed ether, ethyl-hydroxy ethylcellulose is also available. This is similar to ethylcellulose but has broader solubility characteristics. 

Figure 4.11 Volume finction profiles during creaming of an emulsion with 0.04% hydroxy-ethylcellulose (HEC), showing a flocculated network...

Figure 4.13 Delay time versus polymer concentration for emulsions containing hydroxy-ethylcellulose (HEC) orxanthan...

Kelzan XC Kelzan Methyl hydroxy-ethylcellulose Stabilizer, foam cereals GRINDSTED Xanthan 200 GRIND-STED Xanthan EASY Stabilizer, foam cheeses GRINDSTED Xanthan 200 GRIND-STED Xanthan EASY Stabilizer, foam chemical speciaKies Solan 50... 

Stabilizer, foam mining Kelzan XC Kelzan Methyl hydroxy-ethylcellulose... 

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