Modifications of cellulose

Cellulosics. CeUulosic adhesives are obtained by modification of cellulose [9004-34-6] (qv) which comes from cotton linters and wood pulp. Cellulose can be nitrated to provide cellulose nitrate [9004-70-0] which is soluble in organic solvents. When cellulose nitrate is dissolved in amyl acetate [628-63-7] for example, a general purpose solvent-based adhesive which is both waterproof and flexible is formed. Cellulose esterification leads to materials such as cellulose acetate [9004-35-7], which has been used as a pressure-sensitive adhesive tape backing. Cellulose can also be ethoxylated, providing hydroxyethylceUulose which is useful as a thickening agent for poly(vinyl acetate) emulsion adhesives. Etherification leads to materials such as methylceUulose [9004-67-5] which are soluble in water and can be modified with glyceral [56-81-5] to produce adhesives used as wallpaper paste (see Cellulose esters Cellulose ethers). 

Some references distinguish between synthetic fibers made from synthetic polymers and those made by modification of cellulose (man-made fibers). 

The photo-induced process of modification of cellulose and its derivatives was reported by Geacintov and coworkers [67,68]. Thus, acrylonitrile, vinyl acetate, styrene, MMA, and the binary system of styrene and AN were grafted onto cellulose and cellulose derivatives. In... 

Polymers are very large organic molecules that are either made synthetically or are of natural origin, and find use as plastics, rubber, fibers, and coatings. Polymers were first produced commercially in 1860 by modification of cellulose from wood or cotton, followed by a fully synthetic product made from phenol and formaldehyde in 1910. 

Recent years have seen considerable research into the modification of cellulose and reactive dyes, specifically to overcome some of the drawbacks of this dye-fibre system, including the limited degree of fixation in full depths, the need for alkali and relatively high concentrations of electrolyte. This research, which is driven by environmental considerations, was discussed in sections 7.10 and 10.9.1. Thus it need not be considered further here. 

Surface Modifications of Cellulose and Polyvinyl Alcohol, and Determination of the Surface Density of the Hydroxyl Group... 

Surface Modification of Cellulose and PVA Films. Cellulose, as well as PVA,is known to be a typical non-ionic, hydrophilic polymer possessing hydroxyl groups. As this group has a high reactivity,chemical modification of these polymers is relatively easy and, in fact, has been the subject of extensive research. However, so far as we know, no work has been reported concerned with reactions occurring only at the surface of films or fibers from these polymers. 

Arthur, J. C., Jr., Chemical Modification of Cellulose and its Derivatives, Chap. 2 in Comprehensive Polymer Science, Vol. 6, G. C. Eastmond, A. Ledwith, S. Russo, and P. Sigwalt, eds., Pergamon Press, Oxford, 1989. 

A STUDY WITH PLANE-POLARIZED INFRARED RADIATION OF SOME CRYSTALLINE MODIFICATIONS OF CELLULOSE ... 

The most simple modification of cellulose leading to the formation of radical producing groups is ozonization. The action of ozonized oxygen creates hydroperoxide sites which at elevated temperature split into radicals initiating grafting and homopolymerization. 

Millett, M. A. Goedken, V. L. Modification of Cellulose Fine Structures—... 

Both chemical and macromolecular modifications of celluloses to increase their usefulness in applications in films, fibers, and plastics have been reported (1-7). In the context of this discussion, the macromolecular modification of cellulose by graft or block polymerization with vinyl monomers will be considered. 

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