Cellulose water-soluble

Cellulose Deriva.tives, Cellulose can be derivatized to make both water-soluble gums and hydrophobic polymers. The preparation of the hydrophobic cellulose esters (qv), cellulose acetates and cellulose nitrates, has already been mentioned. The water-soluble cellulose derivatives are cellulose ethers (qv). 

An example of the first type is the emulsion stabiliser as exemplified by sodium oleyl sulphate, cetyl pyridinium chloride and poly(ethylene oxide) derivatives. For a number of applications it is desirable that the latex be thickened before use, in which case thickening agents such as water-soluble cellulose ethers or certain alginates or methacrylates may be employed. Antifoams such as silicone oils are occasionally required. 

A number of water-soluble cellulose ethers are marketed." Methyl cellulose is prepared by a method similar to that used for ethyl cellulose. A degree of substitution of 1.6-1.8 is usual since the resultant ether is soluble in cold water but not in hot. It is used as a thickening agent and emulsifier in cosmetics, as a paper size, in pharmaceuticals, in ceramics and in leather tanning operations. 

The heat exchanger fins from aluminum or its alloy are coated with aqueous solution containing a water-soluble cellulose resin or polyvinyl alcohol and a surfactant to form a hydrophilic film. Phosphoric acid ester was used as anionic surfactant (0.05-4.5%) in aqueous solution to form a hydrophilic film showing contact angle with water of 5-32° [288]. 

Barth, H. G. and Regnier, F. E., High-performance gel permeation chromatography of water-soluble cellulosics, /. Chromatogr., 192, 275, 1980. 

Barth, H.G. and Regnier, F.E. "High Performance Gel Permeation Chromatography of Water-Soluble Cellulosics." J. Chromatog.(19801 192, 275 293. 

Emulsion as an Explosive. D.R. Wiggam (USP 1999828 CA 29, 4180(1935) prepd an emulsion suitable as an explosive by rapidly agitating NG with a water-soluble cellulose ether, such as methyl cellulose Ref Clift Fedoroff, Vol 2(1943), p El... 

Refs l)Hercules Powder Co, "CMC. A Water-Soluble Cellulose Gum , Wilmington,... 

Different water-soluble cellulose derivatives have been used for the determination of endocellulase activities. Carboxymethylcellulose (CMC) has been proposed as substrate and recently Almin et al. (3) have improved their method for the calculation of endocellulase activities, using a medium-molecular-weight CMC (Mv = 299,000 and Mw = 142,000) with well-defined physicochemical properties. No corrections... 

Most experiments were performed with cotton or cotton linters as highly crystalline celluloses. Table I shows conditions leading to complete dissolution. A minimum amount of an acid which forms a cellulose ester (sulfuric or trifluoromethylsulfuric acid) (Entries 5 7-14) is necessary for the reaction. The dissolution is accelerated by a temperature increase (Entries 10-12 13, 14) and leads to water-soluble cellulose acetate hydrogensulfate. Whereas this primary hydrolysis can be achieved within 1-5 min, the deesterification and complete hydrolysis of the soluble cellulose derivative proved to be much more difficult. This is in contrast to the generally accepted view that the main resistance to the hydrolysis of cellulose lies in the crystalline nature or low accessibility determining the heterogeneous first step of the reaction. 

Nojiri, M., and Kondo, T. 1999. Kinetic studies of cellulase for water-soluble cellulose derivates. In Ohmiya, K., Hayashi, K., Sakka, K., Kobayashi, Y., Karita, S., and Kimura, T. (Eds.), Genetics, biochemistry and ecology of cellulose degradation (pp. 199-206). Tokyo Uni Publishers Co. 

Gomez-Bujedo, S., Fleury, E., and Vignon, M. R., Preparation of cellouronic acids and partially acetylated cel-louronic acids by TEMPO/NaCIO oxidation of water-soluble cellulose acetate. Biomacromolecules 2004,5 (2), 565-571. 

Soluble in organic solvents, insoluble in water and GI fluids used alone in modified-release formulations and in combination with water-soluble cellulose for immediate-release formulations Soluble in water and GI fluids... 

A new class of water soluble cellulosic polymers currently receiving attention Is characterized by structures with hydrophobic moieties. Such polymers exhibit definite surface activity at alr-llquld and liquid-liquid Interfaces. By virtue of their hydrophobic groups, they also exhibit Interesting association characteristics In solution. In this paper, results are presented on the solution and Interfaclal properties of a cationic cellulosic polymer with hydrophobic groups and Its Interactions with conventional surfactants are discussed. 

C-NMR spectra of water soluble cellulose model compounds indicate that formaldehyde is capable of reacting with wood cellulose functions under hot press conditions as well as at room temperature yielding hemiacetals. The formation of hemiacetals is reversible, and thus constitutes a reservoir for formaldehyde storage. Due to its affinity for water, formaldehyde released during the manufacture of UF-resin bonded products will be retained in the aqueous phase of wood. Wood contains about 9 wt% of moisture. Most of this is in the S-2 secondary cell walls that consist mainly of wood cel IuIose. 

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